air quality sampling manual

1 Air quality sampling manual • November 1997 • ISBN 0 7242 6998 3

Table of contentsGlossary of terms

Introduction

1 Air quality — general issues1.1 Measurement of meteorological parameters

1.1.1 Parameters to be measured1.1.2 Siting requirements for meteorological

sensors1.2 Siting of ambient air quality stations

1.2.1 Site considerations — general1.2.2 Classification of site1.2.3 Representation of population exposure1.2.4 Representation of maximum ground level

concentration (GLC)1.2.5 Influence of nearby emissions1.2.6 Influence of nearby vegetation

1.3 Sample inlet/sample line1.3.1 Free air movement1.3.2 Rain hood1.3.3 General sample system design1.3.4 Condensation1.3.5 Materials of construction1.3.6 In-line filter1.3.7 Checking for leaks in sample system

1.4 Selection of measurement technique1.4.1 Level and time average of appropriate

health standard1.4.2 Batch or continuous sampling

1.5 Quality management1.5.1 Sampling1.5.2 Calibration gases1.5.3 Instrument calibration1.5.4 Maintenance programs1.5.5 Data assessment1.5.6 Reporting1.5.7 Staff training

2 Air quality methods2.1 Carbon monoxide

2.1.1 Siting considerations2.1.2 Methods2.1.3 Factors affecting method choice2.1.4 Recommended method2.1.5 Difficulties likely to be encountered

2.2 Lead2.2.1 Siting considerations2.2.2 Methods2.2.3 Factors affecting method choice2.2.4 Recommended methods2.2.5 Difficulties likely to be encountered

2.3 Oxides of nitrogen (NO & NO2)2.3.1 Siting considerations2.3.2 Methods2.3.3 Factors affecting method choice2.3.4 Recommended methods2.3.5 Difficulties likely to be encountered

2.4 Ozone2.4.1 Siting considerations2.4.2 Methods2.4.3 Factors affecting method choice2.4.4 Recommended methods2.4.5 Difficulties likely to be encountered

2.5 Sulfates2.5.1 Siting considerations2.5.2 Methods2.5.3 Factors affecting method choice2.5.4 Recommended method2.5.5 Difficulties likely to be encountered

2.6 Sulfur dioxide2.6.1 Siting considerations2.6.2 Methods2.6.3 Factors affecting method choice2.6.4 Recommended method

2.7 Dust deposition2.7.1 Recommended method

2.8 Total suspended particulates (TSP)2.8.1 Siting considerations2.8.2 Recommended methods2.8.3 Difficulties likely to be encountered

2.9 Particulate matter with aerodynamic diameterless than 10 µm (PM10)2.9.1 Siting considerations2.9.2 Methods2.9.3 Factors affecting method choice2.9.4 Recommended methods2.9.5 Difficulties likely to be encountered

2.10 Fine particles2.10.1 Siting considerations2.10.2 Methods2.10.3 Factors affecting method choice2.10.4 Recommended methods

2.11 Visibility2.11.1 Methods2.11.2 Factors affecting method choice2.11.3 Recommended method2.11.4 Difficulties likely to be encountered

2.12 Open path spectrometry2.12.1 Methods2.12.2 Factors affecting method choice2.12.3 Recommended method2.12.4 Difficulties likely to be encountered

2.13 Recommended air quality test methods— summary

3 Emission testing — general issues3.1 General requirements for source testing

3.1.1 Staff3.1.2 Methodology3.1.3 Equipment calibration3.1.4 Facilities3.1.5 Documentation3.1.6 Quality management3.1.7 Laboratory accreditation3.1.8 Common sources of error

3.2 Sampling plane selection for particulate sampling3.3 Sampling point requirements3.4 Work platform requirements3.5 Health and safety considerations3.6 Sample handling/chain of custody3.7 Report formats

© The State of Queensland.Department of Environment . 1997

Copyright protects this publication. Except for purposes permitted by theCopyright Act, reproduction by whatever means is prohibited without the priorwritten permission of the Department of Environment .Enquiries should be addressed toPO Box 155 BRISBANE ALBERT STREET QLD 4002.

MU59-1 November 1997Produced by the Department of Environment .Recycled paper saves energy and resources

Air quality sampling manual • November 1997 • ISBN 0 7242 6998 3 2

3.8 Equipment calibration3.8.1 Anemometers3.8.2 Barometers3.8.3 Continuous emission monitoring analysers3.8.4 Gas meters3.8.5 Manometers3.8.6 Nozzles3.8.7 Pitot tubes3.8.8 Reference gas mixtures3.8.9 Rotameters3.8.10 Stop watches/timing devices3.8.11 Thermocouples3.8.12 Thermometers

4 Atmospheric contaminant emission test methods4.1 Opacity

4.1.1 Methods4.1.2 Factors affecting method choice4.1.3 Recommended methods4.1.4 Difficulties likely to be encountered

4.2 Solid particulate matter4.2.1 Recommended method4.2.2 Difficulties likely to be encountered

4.3 Sulfuric acid mist/sulfur trioxide/sulfur dioxide4.3.1 Recommended methods4.3.2 Difficulties likely to be encountered

4.4 Total acid gases4.4.1 Methods4.4.2 Factors affecting method choice4.4.3 Recommended method

4.5 Nitric acid4.5.1 Methods4.5.2 Factors affecting method choice4.5.3 Recommended method

4.6 Oxides of nitrogen (NO & NO2)4.6.1 Methods4.6.2 Factors affecting method choice4.6.3 Recommended methods4.6.4 Difficulties likely to be encountered

4.7 Fluorine and chlorine compounds4.7.1 Recommended methods

4.8 Carbon monoxide4.8.1 Recommended methods

4.9 Hydrogen sulfide4.9.1 Recommended methods4.9.2 Difficulties likely to be encountered

4.10 Heavy metals (excluding mercury)4.10.1 Methods4.10.2 Factors affecting method choice4.10.3 Recommended method

4.11 Mercury4.11.1 Methods4.11.2 Factors affecting method choice4.11.3 Recommended methods

4.12 Vinyl chloride monomer4.12.1 Recommended methods4.12.2 Difficulties likely to be encountered

4.13 Open path spectrometry4.13.1 Methods4.13.2 Factors affecting method choice4.13.3 Recommended methods4.13.4 Difficulties likely to be encountered

4.14 Recommended test methods — summary

5 Other atmospheric contaminants5.1 General issues5.2 Sampling5.3 Analysis5.4 Method choice

6 Biological monitoring6.1 Introduction6.2 Fluoride

6.2.1 Sample preparation6.2.2 Analytical methods

List of tablesTable 1. Summary of recommended air quality methodsTable 2. Recommended emission test methods

Glossary of termsAAS atomic absorption spectroscopyACCU automated cartridge collection unitASP Aerosol Sampling ProjectCBD central business districtCSIRO Commonwealth Scientific and Industrial

Research OrganisationDOAS differential optical absorption spectrometryFTIR Fourier transform infra-redGC-FID gas chromatography with methanization

and flame ionisation detectionGFC gas filter correlationGLC ground level concentrationHVS high volume samplingICP inductive coupled plasmaIR infra-redISO International Standards OrganisationNATA National Association of Testing AuthoritiesNDIR non-dispersive infra-redNHMRC National Health and Medical Research

CouncilNIOSH National Institute for Occupational Safety

& HealthPIXE particle-induced X-ray emissionsPM

10particulate matter with aerodynamic diameterless than 10 µm

PM2.5 particulate matter with aerodynamic diameterless than 2.5 µm

QMS Quality Management SystemSA EPA South Australian Office of the Environment

Protection AuthorityTEOM tapered element oscillating microbalanceTSP total suspended particulatesUSEPA United States Environmental Protection

AgencyUV ultravioletVic EPA Environment Protection Authority of Victoria


IntroductionThis manual provides guidance on measuring ambient airquality and emissions of contaminants into the atmosphere.Methods recommended here represent reliable soundpractice, sufficient to provide data that will enablecomparisons against guidelines, goals or standards.

Measuring air pollution is a complex task and requires duecare and diligence. Valid data can only be obtained when:• siting or sample points are appropriate;• the sample is representative in time and space and

in terms of the process (for emissions);• the sampling equipment, analysis and calibration

techniques are appropriate; and• appropriate quality management procedures are

incorporated.

Following sections deal with these issues in detail.

1 Air quality — general issues1.1 Measurement of meteorological

parametersMeteorology has a major influence on the initial dispersionof plumes, fugitive emissions and area sources, and on themovement of air parcels containing air contaminants.Therefore, meteorological measurements are an essentialcomplement to air quality measurements.

1.1.1 Parameters to be measuredWind speed, wind direction and temperature are themost important variables to measure in air pollutionmeteorological studies. This manual summarises methodssuitable for measuring these parameters near ground level.

It does not deal with more specialised meteorologicalmeasurements taken at higher levels, such as thosefrom very tall masts, balloons, tethersondes, radiosondesor by acoustic radar. Nor does it discuss parametersmeasured to establish meteorological data for atmosphericdispersion modelling, such as solar radiation andsigma theta.

Australian Standard AS 2923 ‘Ambient Air — Guide forMeasurement of Horizontal Wind for Air QualityApplications’ sets out a guide for measuring horizontalwind speed and direction. This standard should befollowed as closely as possible where conditions permit.The standard is applicable at various sensor heights, but10 m above ground level is preferred.

As air temperature does not change rapidly, a rapidresponse rate is not required but measurements mustbe continuous and recorded. Typical recording devicesinclude a mechanical thermograph (with an accuracyof approximately 1oC) or the more precise electricalresistance thermometers. Sensors need to be housed outof direct sunlight such as in a Stephenson screen or witha sun shield and continuous aspiration.

1.1.2 Siting requirements for meteorological sensorsAustralian Standard AS 2923 ‘Ambient Air —Guide for Measurement of Horizontal Wind for Air QualityApplications’ sets out recommended siting requirementsfor anemometers in terms of mounting, exposure andprotection in adverse conditions. Where theserecommendations cannot be adhered to, a site shouldbe chosen that meets the criteria as closely as possible.Significant deviation from the guide should be notedwhen reporting data.

Location of the instrument is critical. Incorrect siting, suchas in a sheltered location or on a small building or hill, mayresult in wind variations of - 50% to + 100% in wind speed,and 90 degrees or more in wind direction from the windrepresentative of the general area.

Measurements should be made at 10 m above groundlevel in an area free of obstructions. As a general rule, theanemometer should be sited at a location distant from anyobstruction by at least 10 times the height of theobstruction.

If the site is likely to experience icing, some form of heatingmay be necessary to allow sensors to operate during theseconditions. Anemometer masts are prone to lightningstrikes and the Australian Standard AS 1768 ‘LighteningProtection’ should be consulted for lightning risk levelsand on protective measures. The mast should be earthedand cables encased in suitably earthed metal conduits.

Temperature sensors are often sited at the same positionas the anemometer. Siting of temperature sensors is notas critical as it is for anemometers in terms of proximity totall obstructions, but sensors need to be far enough fromobjects that may radiate excessive heat. The temperaturerequired is the air temperature, so direct sunlight andnearness to large masses that may absorb, radiate orreflect heat is to be avoided. For sensitive measurements,air aspiration may be used but, in such cases, it is essentialthat any heat developed by the air mover or fan is nottransferred to the air being measured.

1.2 Siting of ambient air qualitystations

Siting of ambient monitors can have a profound influenceon air quality values recorded. No amount of quality controland precision in sampling and analysis can overcomedeficiencies of site selection. Australian Standard AS 2922‘Ambient Air — Guide for the Siting of Sampling Units’ isrecommended. The standard sets out general guidelinesfor siting ambient air quality monitors and specifies anumber of siting parameters for individual air contaminants.

The standard is a guide and adherence is not mandatory.In some cases, the object of monitoring may require avariation from the standard. In other cases, it may not bepossible to adhere to the standard. Certain studies may,for example, require measurement in street canyons ornear to roadways. Where siting does not conform with thestandard, this should be reported with the results.

The site should be representative of the location beingassessed. It should not be unduly influenced by immediatesurroundings unless those influences are specifically beingmeasured, for example, near a busy road, a factory stack ora dusty quarry.

A site may satisfy criteria when established butsurroundings may change over time, for example,through construction or vegetation growth.

1.2.1 Site considerations — generalSites chosen for unattended operation should be secureand have a low potential for vandalism. Long-term sitesshould have adequate services. Mains power needs to beavailable and must be free of interruption. If power surgesare likely, a surge prevention device must be provided.Telephone lines or a cellular network are generallynecessary to provide voice and modem communication.Air conditioning is generally required, except for the mostbasic sampling.


Sites should provide adequate access for vehicles totransport heavy instruments and gas cylinders. The siteshould not be subject to flooding, and the site classificationor situation should not change over time. This can occur asvegetation grows, during building construction and roaddetours, or if the area is used as a car park on certain days.

1.2.2 Classification of siteIn establishing a monitoring network to assess air qualityover an area, stations in a variety of classifications may berequired. Population density, emission sources, localdevelopment and contaminants to be measured will allimpact on the type of site required.

Australian Standard AS 2922 ‘Ambient Air — Guide for theSiting of Sampling Units’ classifies ambient air qualitystations into 3 categories:

Peak stations: are located in areas where the maximumground level concentration (GLC) is likely to be measured.They are useful for compliance monitoring in the vicinity ofa source.

Neighbourhood stations: are generally located in anarea representative of uniform land use such as residential,industrial or commercial. These stations are used to assesscompliance with air quality standards and to measuretrends over time.

Background stations: are sited to assess air quality inareas without substantial sources and may be useful inproviding background levels and measuring levelsresulting from transport of pollution.

In practice, a site may satisfy more than one category at thesame time. However, a site that satisfies a classification fora particular contaminant may be invalid for another. Forexample, a site in a street canyon could be a peak site forlead, but would be unsuitable for use under anyclassification for ozone.

1.2.3 Representation of population exposureNeighbourhood sites are frequently used to assesscompliance with air quality standards. Sites are selectedso that they sample the air to which the population isexposed, and so that the time likely to be spent in thevicinity of the site is comparable to the averaging periodused in the air quality standard being considered.

A site may satisfy this criteria for some contaminants butmay not for other contaminants. A site near a point sourceof sulfur dioxide and lead, where people move through butdo not reside, may be suitable for assessing complianceagainst a ten-minute goal for sulfur dioxide, but not againsta three-month goal for lead.

1.2.4 Representation of maximum ground levelconcentration (GLC)

To assess the impact of a point source on ambient airquality, the monitoring station should be sited where themaximum GLC is expected. This may be based oncomplaints, experience or output from an atmosphericdispersion model. In the case of fugitive emissions, themaximum GLC may be very near the source and mayhave undergone minimum dispersion.

1.2.5 Influence of nearby emissionsSites for monitoring should be established to give arepresentative measure of the air quality in a locality.Unless there is a specific intention to do otherwise, sitesshould be chosen to avoid immediate proximity to localsources. Australian Standard AS 2922 ‘Ambient Air —Guide for the Siting of Sampling Units’ recommends theminimum distance from known sources for mostcontaminants.

Siting situations to be avoided include:• measuring ozone near fresh emissions, especially near

motor vehicle traffic;• measuring particles near domestic or commercial

incinerators or dusty roads; and• measuring near fugitive emissions that may escape

from a premises, unless that is the intention of the study.

1.2.6 Influence of nearby vegetationAs a general rule, monitoring sites should not be locatedin close proximity to leafy vegetation. The influence ofvegetation on the readings can be positive or negative.

Natural decay of vegetation will cause particles to dropor blow into the air, and these may give artificially raiseparticle concentration. Conversely, leafy vegetation mayfilter out particles from the air and produce a lower readingthan the general locality.

Some air contaminants react chemically with vegetationand, as they pass through leaves, will attack the vegetation,reducing the contaminant concentration. Gases in thiscategory include ozone, sulfur dioxide, hydrogen fluorideand other fluorides, nitrogen dioxide and a range of acidgases and particles.

1.3 Sample inlet/sample lineThe integrity of the sample to be analysed will becompromised if the sample inlet or sample line changesthe sample before analysis. The purpose of a samplesystem is to withdraw a sample of air and present it tothe analysis system, without significant change to thecomposition or characteristics of the sample. The samplesystem will generally consist of a sample inlet, an exteriorsample line, an internal sample line, a moisture removalsystem, a filter, a manifold (where more than one analyseris operating from the sample line), an instrument sampleline and a pump or pumps.

An effective sample line will satisfy the following criteria:• impart no change in concentration of the component

of interest;• remove components or agents such as condensed

moisture and dust, which could interfere withthe analysis;

• be reliable, with low maintenance requirements; and• be able to withstand the elements, wildlife and vandals.

1.3.1 Free air movementThe sample inlet needs to sample air that is representativeof the general locality, not air that is in a confined space.This is particularly true for reactive gases and particles.

1.3.2 Rain hoodThe sample inlet must allow the entry of free air, withoutpermitting rain to enter. The rain hood must be of materialthat can withstand the elements (including sunlight, hailand the occasional stone) and will not react with the gasesbeing measured. For some particles, it needs to createa particle size partitioning function to exclude unwantedparticles but include the particles of interest.

Rain hoods designed to partition particles must bemaintained to ensure that critical specifications aresatisfied over the working life of the sampling equipment.

1.3.3 General sample system designSample systems are generally classified into two majorcategories depending on whether the system handlesone measuring device or a number of devices.


When sampling is dedicated for one sample measurementdevice, the system normally consists of a sample inlet,a sample line and in-line filter and filter holder, and theinstrument. All materials must be inert to the contaminantof interest. The instrument pump normally provides thevacuum necessary for sampling. In the case of reactivegases, the system should be designed to ensure theresidence time of the sample in the line is insufficient topermit significant reaction by the contaminants of interest.

High-volume samplers used for particulate measurementshave the sample system as an integral component of thesampler shelter.

In more comprehensive monitoring stations where anumber of parameters are being measured, it is commonto use a larger-scale system incorporating a wide borevertical sample line, a manifold to permit individualanalysers to withdraw the air simultaneously, and a largepump or fan to move air through the common sample line.

A variation on the large-scale sampling system uses thelaminar flow principle. While laminar flow conditions aremaintained, the majority of air passes down the sampleline without contact with the internal materials of the duct.Samples to the individual instruments are drawn throughprobes, inert to the contaminants of interest, inserted intothe centre of the laminar flow.

All sampling systems must be designed to enable cleaningor replacement of the entire system before the instrumentintake and to allow inspection to check for soiling andinsects in the system.

Sample systems for some instruments need specificdesign. Sample systems for integrating nephelometersrequire heating to bring the sample above dew point toremove fog.

Sampling systems should be designed to permit leaktesting and the insertion of calibration gases through thesample system.

1.3.4 CondensationIn humid areas and under some conditions of rain,condensation in the sample line can cause difficultiesin sampling.

Condensation is likely to occur in the sample line underconditions of high ambient temperature and high relativehumidity. The most common problem occurs when the hot,humid sample air is drawn into an air-conditionedmonitoring station. The air can fall below the dew pointand cause condensation. This condensation can ‘blind’filters, dissolve soluble contaminants and be drawn intothe reaction cell of the measuring device.

Methods to prevent condensation include:• temperature regimes within the monitoring stations;• electrically heated sample lines through to the

detection cells;• desiccants (which must be replaced);• permeation devices; and• dropout bottles (which must be emptied).

The recommended method is to establish a temperatureregime that prevents condensation while still allowinginstruments to operate within their design criteria.Maintaining the temperature at 25–28 °C is one methodthat has been used successfully in high ambienttemperatures and humidity. At this temperature,instruments can perform to specifications and conditionsare still suitable for operators.

1.3.5 Materials of constructionMost gases of concern in air quality studies can be reactiveon contact with most materials. This is certainly the casewith ozone, sulfur dioxide and nitrogen dioxide. Althoughsome gases, such as carbon monoxide, are less reactive,it is good practice to use materials of construction in thesample line that are inert to most gases.

Preferred materials for almost all gaseous sampling areteflon and glass. These are necessary for the sample inlet,the sample line and the filter and filter holder.

To provide protection from the elements and vandalism,materials are sometimes enclosed in more rigid outerprotection. On a single sample system, this can includeusing a plastic or metal outer pipe and possibly a funnel.In the case of the large-scale multi-gas system, the inletcover is often machined from solid teflon and the inletline encased in metal pipe.

Instruments sited in the open generally have samplesystems incorporated in the unit. This is the case for thehigh-volume sampler used for particulates measurement,where the rain hood/particle size separator is an integralpart of the sampler. Some specific instruments, such asthe tapered element oscillating microbalance (TEOM) andsometimes the integrating nephelometer and dichotomoussampler come with dedicated sample systems.

1.3.6 In-line filterIn sampling for gases, an in-line filter is essential tomaintain clean sample cells or reaction chambers.As most gases are reactive, teflon filters and filter holdersare recommended. A 5 mm pore size teflon filter iscommonly used, with a diameter of approximately 47 mm.

The filter needs to be replaced before the build-up ofparticles reacts with the contaminants of interest to asignificant degree or the pressure drop compromises thesample flow rate. The frequency of filter replacement willdepend on the contaminants being measured and thedust loading at the site. Regular checking of the degree ofbuild-up on the filter and calibration through the filter willhelp establish the timing for replacement.

If electrically heated sample lines are used to overcomecondensation, it is necessary to also heat the filter and filterholder assembly.

1.3.7 Checking for leaks in sample systemSample systems can be complex, incorporating a range oflines, filters and connections. The integrity of the samplecan only be preserved if the sample system is routinelychecked for leaks.

In the case of single instrument sample lines, the inlet canbe blocked off and the flow checked. If no leaks exist, thesample flow will come to a halt in a short time. If the flowdoes not stop, the source of the leak should be located andrectified. The most effective way to detect the source is tostart near the pump and work back from each potential leakpoint to the sample inlet.

In multi-gas systems, the sample line from the manifoldshould be checked to ensure an airtight connection.The individual sample line from the manifold should thenbe blocked and checked downstream. In these systems,the flow into the common sample inlet and the operationof the blower must be routinely checked to maintain theintegrity of the air flow in the system.


1.4 Selection of measurementtechnique

When selecting measurement techniques, it is importantto consider the final use for which the results are required.In most cases, data collected will be compared withrelevant health standards and goals, or with estimatedmaximum GLCs. Method selection needs to considerthe following issues.

1.4.1 Level and time average of appropriate heathstandard

In most cases, ambient monitoring is conducted to assessair quality against the appropriate health standards. Lessfrequently, monitoring is conducted to measure maximumGLCs at peak sites to determine maximum impacts on theenvironment.

The method chosen must be able to provide themeasurement sensitively, accurately and specifically,determining concentrations in the time average requiredby the health standard.

1.4.2 Batch or continuous samplingBatch sampling provides pollution concentration valuesaveraged over certain time periods. It cannot provide datafor periods when sampling was not conducted, and canonly provide data for averaging periods equal to or greaterthan the sampling period. For example, daily averages forparticulates can be used to compile three-month averagesbut cannot be used to provide one-hour averages.

Many air quality standards specify an average level not tobe exceeded more than once per year. This is the case forozone, where the National Health and Medical ResearchCouncil (NHMRC) goal is a one-hour level not to beexceeded more than once per year. To assess compliancewith this goal, it is necessary to measure in time periods ofnot less than one hour (usually continuously). Furthermore,unless every hour is monitored, it is not possible todetermine if an exceedance occurred at some other timeduring the year when monitoring was not conducted.

1.5 Quality managementAll monitoring programs and activities should beincorporated into a quality management system (QMS).Effective application of the QMS will provide operationaland management tools to ensure program requirementsare achieved consistently, accurately and reliably.

The QMS should be based on the requirements of thequality standard AS/NZS ISO 9002 ‘Quality Systems —Model for quality assurance in production, installationand servicing’, or similar. Operating and maintenanceprocedures for the monitoring program should coverall appropriate and relevant elements of the abovequality standard.

1.5.1 SamplingThe sampling procedure is a critical element in providingvalid data. No amount of accuracy, precision andcalibration of analytical procedures can overcomeerrors due to inappropriate sampling.

It is essential that the sample site is representative ofthe air quality of interest and the sample taken isrepresentative in time and homogeneity of the air. Factorsinfluencing the integrity of the sample include the source ofthe contaminant, its half-life, wind and thermal turbulence,humidity, density of the contaminant, sunlight, time of day,and the presence of nearby objects. A number ofresearchers have confirmed that the concentration of acontaminant can vary by several orders of magnitudewithin a relatively short radius from a source.

When reporting data, it is important to classify the siteaccording to Australian Standard AS 2922 ‘Ambient Air —Guide for the Siting of Sampling Units’; specify heightabove ground, proximity to sources and reactive surfacesor vegetation (sinks); and specify the location of sampling,including the Australian Map Grid reference.

1.5.2 Calibration gasesMost gaseous air contaminants are calibrated by means ofcompressed standard calibration gases. In the case ofcarbon monoxide, the gas is presented to the instrumentundiluted while, in the case of sulfur dioxide and nitricoxide (for nitrogen dioxide), it is diluted in a precision gasdilution apparatus before presentation. Calibration gasesshould be traceable to international standards or certifiedby the National Association of Testing Authorities (NATA),where appropriate.

Nitrogen dioxide calibration gas is provided by gas phasetitration using standard nitric oxide gas and ozone froma gas generator or by the use of nitrogen dioxidepermeation tubes.

As a consequence of its instability, ozone is unique in thata compressed gas cannot be used for calibration and theozone standard must be generated in situ by precisionozone generation. Commonly, a secondary or transferstandard ozone monitor is calibrated by the primarystandard and this is used to calibrate field monitors.

Australian Standards for the contaminants of interestspecify calibration methods. AS 3580.2.1 ‘Preparation ofReference Test Atmospheres — Permeation Tube Method’and AS 3580.2.2 ‘Preparation of Reference TestAtmospheres — Compressed Gas Method’ should beconsulted for more details on calibration procedures.

1.5.3 Instrument calibrationAll parameters covered in the air quality section specifythe calibration procedure, which is detailed in the method(usually the Australian Standard).

The contaminants of concern are usually in lowconcentrations in the atmosphere and many measurementtechniques are, therefore, approaching their limit ofdetection. As such, regular and careful zero and spancalibrations should be carried out within a sound qualitymanagement system.

Calibrations should be logged in a manual or electronicdata logging system. Calibration standards, the instrumentrecorded values, any adjustments, factors and otherpertinent information should be detailed in record keeping.

1.5.4 Maintenance programsThe quality management system should provide acomplete schedule of maintenance for each instrument.Instruments should be coded, and records of maintenance,routine consumable parts, replacement parts fitted, majorrepairs and lifetime history held in a central file.

The schedule should be monitored by use of a whiteboard,weekly planner or computer program, which will promptaction as well as provide historical records.

1.5.5 Data assessmentThe data provided by each instrument should be regularlychecked for validity and possible errors. Data should bechecked as soon as practical after recording, but the periodbetween checks should not exceed three days. The needfor promptness is twofold:• to detect a problem before a significant amount of data

is lost; and• to examine data while any factors influencing the

readings may still be recalled or checked.


A systematic program of checks should be used to ensurecontinuity and uniformity, but these should be sufficientlyflexible to accommodate new findings. Many of thesechecks can be built into a computer program, if the dataare electronically logged. ‘Windows’ for normal data canbe established, so that data outside these windows areflagged for closer scrutiny. Flags can be constructed fromexperience but would include such things as:• levels above a standard value;• negative values;• rapid increases or decreases of values over certain

time periods;• sudden changes in values above a certain magnitude;

and• constant level or zero values.

While electronic logging is a great benefit in storing datafor later analysis, this form of record keeping often hidesshort-term indications that may highlight a problem, or aproblem in the making. ‘Noisy’ or short-term fluctuations inlevels (indicating possible instrument instability), flat zeroreadings (possibly indicating instrument breakdown orrecorder disconnection), regular diurnal trends (possiblyindicating thermal influences) and other information canoften be noted by an experienced operator scanninginstrument output, but remain unnoticed on a data loggeroutput. Instrument operating procedures should includeregular checks for noise at the instrument (that is, beforethe data is averaged by the data logger).

1.5.6 Reporting‘A job is not finished until the paperwork is done’ is a trueadage when it comes to air quality monitoring. A monitoringstudy is not productive until the data are reported.Reporting data is an output that should not be delayedtoo long. Benefits of early reporting include:• highlighting high values;• reducing instrument down-time;• giving notice of potential instrument problems;• indicating possible impact on the environment;• indicating possible industrial plant upset;• providing data to interested parties; and• permitting feedback on occurrences.

Data reporting must be carefully managed. Just asdata are only as good as the sample allows, the valuesrecorded are only valuable when the data has been fullyand accurately reported to interested and involved parties.Data reports should be proof read in hard copy by anexperienced and qualified practitioner familiar with thesite and the normal air quality expected at the site.

While quality management computer programs availablefor air quality are very valuable, human involvementis essential in the quality management system.

1.5.7 Staff trainingStaff training is essential if quality data are to be generatedand maintained. Air quality measurement is a veryspecialised and unique technology and few techniciansor professionals gain training during formal courses. Whilesome undergraduate and postgraduate courses cover thesubject of air quality, they seldom explore the intricacies ofair quality monitoring. In addition, many of the complexitiesof measurement only come to notice after difficulties areencountered.

Short-term training in air quality monitoring is available inAustralia but is most effective if provided by professionalswell experienced in ‘hands-on’ monitoring and not justtheory. The Clean Air Society of Australia and NewZealand provides courses on air quality monitoring andpublishes manuals on its practical aspects.

The best staff training can often be gained by workingwith experienced technicians. Every opportunity shouldbe taken to enable staff to gain working experience withothers well qualified in the science.

Wherever possible, staff should be NATA-accreditedfor the measurement programs they conduct.

2 Air quality methods2.1 Carbon monoxide2.1.1 Siting considerationsSiting and proximity to emissions and population exposureare important considerations. In most major cities, around90% or more of carbon monoxide emissions come frommotor vehicles. Carbon monoxide emissions generallydisperse quickly in the atmosphere unless they arecontained in areas with poor ventilation. Elevatedconcentrations can be found in city street canyonsin central business districts (CBDs).

In considering instrument siting, due note should begiven to the requirements in AS 2922 ‘Ambient Air— Guide for the Siting of Sampling Units’, which makerecommendations for sampling in proximity to roads forneighbourhood and background sites. CBD sites generallydo not conform to these recommendations and would beclassified as peak sites.

2.1.2 MethodsMethods available include:• non-dispersive infra-red (NDIR) spectrophotometry;• gas filter correlation (GFC);• gas chromatography with methanization and flame

ionisation detection (GC-FID); and• electrochemical.

2.1.3 Factors affecting method choiceThe relevant Australian Standard AS 3580.7.1‘Determination of carbon monoxide — Direct-readinginstrumental method’ is a performance-based standardthat allows for all of the above techniques.

GC-FID has the potential for the lowest detection limit butNDIR and GFC detection limits are more than satisfactory.GC-FID systems are not widely used, probably becauseof their complex design and cyclic batch sampling andanalysis system. GFC has now almost entirely replacedNDIR in the market place. GFC is robust and reliable,and is normally the method of choice for continuousambient monitoring.

Electrochemical instruments cannot always meetrequirements in terms of stability and detection limit toprovide sufficient accuracy to assess compliance witheight-hour goals.

2.1.4 Recommended methodThe technique recommended for routine continuousair quality monitoring is GFC operated in accordancewith AS 3580.7.1 ‘Determination of carbon monoxide —Direct-reading instrumental method’.

NDIR instruments or electrochemical techniques operatedin accordance with this standard can be used in short-termstudies.

2.1.5 Difficulties likely to be encounteredHumidity is always found in the atmosphere and canpresent a problem, especially for NDIR instruments,if the analyser is not appropriately protected.


Span drift can be of concern, especially for long-termcontinuous measurements. This is likely to be of concern,particularly in the case of electrochemical instruments.

Data-recording devices should allow for rapid fluctuationsin concentration that can take place when measuringcarbon monoxide near to roads.

2.2 Lead2.2.1 Siting considerationsIn most major cities, up to around 90% of lead emissionscome from motor vehicles. Lead emissions generallydisperse gradually in the atmosphere in line with thedistance from busy roads.

In considering instrument siting, attention should be paidto siting guidelines in AS 2922 ‘Guide for Siting ofSampling Units’, which make recommendations forsampling in proximity to roads for neighbourhood andbackground sites.

2.2.2 MethodsMethods available include:• high-volume sampling (HVS), acid extraction and

analysis by atomic absorption spectroscopy (AAS);• HVS, acid extraction and inductive coupled plasma

(ICP) analysis;• Aerosol Sampling Project (ASP) low-volume cyclonic

sampler and ion-beam analysis; and• impinger sampling and AAS or ICP analysis.

2.2.3 Factors affecting method choiceA potential benefit of HVS and ICP analysis is the abilityto simultaneously analyse for a wide range of metals inaddition to lead.

A potential benefit of low-volume sampling and ion-beamanalysis is the ability to simultaneously analyse a widerange of elements.

Sampling using the low-volume technique in normalconfiguration collects particles less than 2.5 µm. This is aconsiderably smaller size fraction than collected in the HVSmethods and may not collect all lead particles in the air.Most lead emitted from motor vehicles is less than 2.5 µmwhen emitted, but, on settling and possible re-entrainment,some particles accumulate to particles greater than 2.5mm. Wind-blown dust from stockpiles of ore material willcontain dust greater than 10 mm, and lead that could beinhaled or ingested by humans may escape collection.

Impinger sampling does not lend itself to long-termmonitoring. Sampling for periods over one hour resultsin loss of collection solution, which must then besupplemented. Cooling the impingers in an ice bath or byother techniques will prolong the available sampling time,but 24-hour samples, which are necessary to compile dataon a three-month average, are not easy to collect. Themethod collects volatile lead compounds in addition toparticulate lead, which means that results will not bedirectly compatible with air quality standards developedusing data collected using HVS.

Instrument techniques established in most monitoringnetworks in Australia are Australian Standard AS 2800,using AS 2724.3 or AS 3580.9.6, and the low-volumetechnique using ion-beam analysis.

2.2.4 Recommended methodsTechniques recommended for routine air quality monitoringare HVS in accordance with:• AS 2724.3 ‘Ambient air-Particulate matter

— Determination of total suspended particulates (TSP)— High-volume sampler gravimetric method’; or

• AS 3580.9.6 ‘Ambient air-Particulate matter— Determination of suspended particulate matter— PM

10 high-volume sampler with size-selective inlet

— Gravimetric method’;

followed by acid extraction, and then:• analysis by AAS in accordance with AS 2800 ‘Ambient

air — Determination of particulate lead — High-volumesampler gravimetric collection — Flame atomicabsorption spectrometric method’; or

• ICP analysis, with the ICP analysis calibrated againstthe AAS method using the same sample.

2.2.5 Difficulties likely to be encounteredFilters used for sampling must be sufficient to collect finelead particles and not contain significant background lead.

2.3 Oxides of nitrogen (NO & NO 2)2.3.1 Siting considerationsIn most major cities, around 80% of oxides of nitrogenemissions come from motor vehicles. Oxides of nitrogenemissions disperse in the atmosphere, with nitric oxideslowly converting to nitrogen dioxide and nitrates.

In considering siting instruments, attention should begiven to the siting guides in AS 2922 ‘Guide for Siting ofSampling Units’, which makes recommendations forsampling in proximity to roads for neighbourhood andbackground sites.

2.3.2 MethodsMethods available include:• chemiluminescence;• electrochemical;• passive badges; and• open path spectrometry.

2.3.3 Factors affecting method choiceThe relevant Australian Standard AS 3580.5.1‘Determination of oxides of nitrogen —Chemiluminescence method’ specifies thechemiluminescence method, including the performancecriteria on interference equivalence and other parameters.

Electrochemical sensors generally have a detection limitabove 0.01 ppm and, when operating near this level,often suffer significant drift problems.

Passive badges can provide averages of NO2

concentration over sampling periods of several hoursand upwards. Sampling for a one-hour period givesinsufficient detection limit for routine ambient monitoringof concentrations normally experienced at neighbourhoodsites. The short-time average of the NHMRC goalexpressed as ‘not to be exceeded more than once permonth’ rules out batch, non-continuous, sampling.This means badge sampling is not appropriate.

Chemiluminescent instruments complying with therequirements in United States Environmental ProtectionAgency (USEPA) rules may achieve designation underthe USEPA rules. As such, they would be capable of thedetection limit required to meet the level of theNHMRC goals.

The detection limit of electrochemical sensors is generallyinsufficient to provide reliable assessment against the levelof the NHMRC goal. The goal requires a detection limitnot more than 0.01 ppm and this, coupled with thecontinuous monitoring requirement, would rule out theelectrochemical cell sensor on grounds of limit of detectionand long-term drift.

Chemiluminescence is the instrument techniqueestablished in most continuous monitoring networks.


2.3.4 Recommended methodsTechniques recommended for routine air qualitymonitoring are:• chemiluminescence with instruments designated by

the USEPA and operated in accordance with theAustralian Standard AS 3580.5.1 ‘Determination ofoxides of nitrogen — Chemiluminescence method’; or

• ultraviolet (UV) differential optical absorptionspectrometry (DOAS) operated in accordance withUSEPA Equivalent Method EQNA-0495-102 ‘OpsisModel AR 500 System, open path (long path) ambientair monitoring system configured for measuring NO

2’.

2.3.5 Difficulties likely to be encounteredChemiluminescent instruments detect nitrogen dioxide onthe basis of chemiluminescence of nitric oxide and thusrely on the efficiency of the converter to reduce nitrogendioxide to nitric oxide. The method therefore relies on theefficiency of the converter. The Australian Standardrequires this converter efficiency remains in excess of 98%.

The converter efficiency should be checked using gasphase titration with ozone, at least once per month, or morefrequently in cases where high levels of nitrogen dioxideare regularly encountered.

2.4 Ozone2.4.1 Siting considerationsOzone sampling should not be undertaken in the CBDor near busy streets. Instead, it should be conducted tomeasure general population exposure. It is very importantnot to measure ozone near fresh emissions of combustionproducts (that is, nitric oxide) because of the ‘quenching’action shown in the equation,

O3 + NO < == > O

2 + NO

2

which drives the reaction to the right, removes ozoneand produces nitrogen dioxide. This quenching effect isgenerally only temporary. Under photochemical smogconditions, more ozone is generated at a later time.

Monitoring for ozone should meet the siting requirementsin AS 2922 ‘Guide for Siting of Sampling Units’, whichmakes recommendations for sampling in proximity toroads for neighbourhood and background sites.

In addition, sites should not be in close proximity to leafyvegetation, because the ozone content in air passingthrough trees will be reduced by reaction with the leaves.

2.4.2 MethodsMethods available include:• ultraviolet absorption;• chemiluminescence; and• open path spectrometry.

2.4.3 Factors affecting method choiceThe relevant Australian Standard, AS 3580.6.1‘Determination of Ozone — Direct-reading instrumentalmethod’ is a performance-based standard that allows forboth UV absorption and chemiluminescence.

The NHMRC air quality goals for ozone are one-hour andfour-hour averages, the one-hour average not to beexceeded more than once a year. This essentially requirescontinuous measurement, which both chemiluminescentand UV absorption methods provide.

Chemiluminescent and UV absorption instruments areestablished in most continuous monitoring networks.In recent times, however, UV absorption has almostachieved market saturation.

2.4.4 Recommended methodsTechniques recommended for routine air qualitymonitoring are:• UV absorption with instruments designated by the

USEPA and operated in accordance with the AustralianStandard AS 3580.6.1 ‘Determination of Ozone —Direct-reading instrumental method’; or

• UV DOAS operated in accordance with USEPAEquivalent Method EQOA-0495-103 ‘Opsis ModelAR 500 System, open path (long path) ambient airmonitoring system configured for measuring O3’.

2.4.5 Difficulties likely to be encounteredOzone is very unstable and this instability may cause errorin sampling and calibration. Sampling lines must be keptclean and the materials of construction must be glass orteflon. All filters and filter holders should also be teflon.Particles within the sampling lines or excessive build-upof particles on filters will promote ozone degradation.Good practice requires filter changing and line cleaning,or replacement on a planned basis. The frequency willdepend on the particle loading. Visual inspection andcalibration through the sample system will determine thefrequency for a site. The standard specifies a sample linelength as short as practicable and no longer than 10 mand a filter change frequency of not less than weekly.

Calibration of ozone cannot be carried out using certifiedgas mixtures as ozone is far too unstable. Calibration offield instruments is normally carried out using secondary(transfer) standards, which are themselves calibrated usinga primary standard ozone photometer. The calibrationprocedure and the use of transfer standards is specifiedin AS 3580.6.1 ‘Determination of Ozone — Direct-readinginstrumental method’.

2.5 Sulfates2.5.1 Siting considerationsIn considering siting instruments for routine monitoring,note should be taken of the siting requirements in AS 2922‘Guide for Siting of Sampling Units’, which makesrecommendations for sampling in proximity to roads forneighbourhood and background sites.

2.5.2 MethodsMethods available include:• HVS, extraction and ion chromatography;• HVS, extraction and spectrometric analysis; and• ASP low-volume cyclonic sampler and ion-beam

analysis.

2.5.3 Factors affecting method choiceThe NHMRC goal for sulfate is set over an annualmean period. This goal can be assessed by compiling anannual average based on the 24-hour sample collectedthroughout one day in each six-day cycle, or two daysa week. Sampling with an HVS, or low-volume samplingwith analysis as specified above, would provide data ina form with a potential for assessment against this goal.

ASP low-volume cyclonic sampler and ion-beam analysishas the benefit of permitting simultaneous non-destructiveanalysis on a wide range of elements by particle-inducedX-ray emissions (PIXE). PIXE actually detects all sulfurcompounds but, under the conditions of sampling, thisis generally consistent with sulfates.

2.5.4 Recommended methodTechniques recommended for routine air qualitymonitoring are: • HVS in accordance with AS 2724.3 ‘Ambient air-

Particulate matter — Determination of total suspendedparticulates (TSP) — High-volume sampler gravimetricmethod’ or AS 3580.9.6 ‘Ambient air-Particulate matter


— Determination of suspended particulate matter— PM10 high-volume sampler with size-selective inlet— Gravimetric method’, followed by water extraction,and then ion chromatography in accordance withMethod 720A Suppressed Anion Chromatography inMethods of Air Sampling and Analysis, 3rd Edition ofIntersociety Committee AWMA, ACS, AIChE, APWA,ASME, AOAC, HPS, ISA 1988. Ed. James P Lodge Jr;or

• ASP low-volume technique followed by ion-beamanalysis (where acid droplets are not of concern),in accordance with the method described by Cohenet al. (Cohen D.D., Noorman J.T., Garton D.B., StelcerE., Bailey G.M., Johnson E.P., Ferrari L., Rothwell R.,Banks J., Crisp P.T. and Hyde R. ‘Chemical Analysisof Fine Aerosol Particles within 200 km of Sydney:Introduction to the ASP Aerosol Study’. Clean Air Vol 27No. 1 1993).

2.5.5 Difficulties likely to be encounteredSampling using the low-volume technique collects particlesless than 2.5 µm. This is a considerably smaller sizefraction than collected in the HVS methods and may notcollect all sulfate particles (especially acid droplets) in theair. Most sulfate formed from sulfur dioxide will be less than2.5 µm, but some droplets may be greater than 2.5 µm.

Filters used for sampling must be sufficient to collect finesulfate particles and not contain significant backgroundsulfate. The filters should be teflon or teflon coated toprevent reaction of acid sulfates or conversion of sulfurdioxide to acid sulfates. The blank HVS filters must containless than 50 mg per filter of sulfate. The low-volumesampling method specifies teflon filters which have verylow sulfate background levels and high collection efficiencyfor fine particles.

2.6 Sulfur dioxide2.6.1 Siting considerationsIn considering siting instruments for routine monitoring,note should be taken of the siting requirements in AS 2922‘Guide for Siting of Sampling Units’.

Around point sources, instruments should be sited todetermine maximum impact and this must be determinedfrom stack dispersion modelling, residential complaintsand near the boundaries of plant where fugitive emissionsare likely.

In addition, sites should not be in close proximity to leafyvegetation as sulfur dioxide in the air passing through treeswill be reduced by reaction with the leaves.

2.6.2 MethodsMethods available include:• fluorescence;• flame photometry;• ectrochemical (coulimetric or conductimetric); and• open path spectrometry.

2.6.3 Factors affecting method choiceThe relevant Australian Standard, AS 3580.4.1‘Determination of Sulfur Dioxide — Direct-readinginstrumental method’ is a performance-based standardthat allows for instruments incorporating fluorescence,flame photometry or electrochemistry.

The NHMRC air quality goals for sulfur dioxide areaveraged over ten minutes, one hour and one year.

Most significant levels will occur close to point sources,and large fluctuations in concentrations will be observed.Instruments used must have rapid response capabilities.

Instruments using fluorescence detection can meet thedetection level and the time discrimination required.

Instruments using flame photometric detection can easilymeet the detection level but, when operating with GCseparation mode, fail to provide sufficient timediscrimination for the ten-minute goal.

Instruments operating on the electrochemical principalare generally unsatisfactory on grounds of interferenceby other gases and, generally, on time discrimination.

Most continuous monitoring networks use fluorescencealmost exclusively.

2.6.4 Recommended methodTechniques recommended for routine air qualitymonitoring are:• fluorescence operated in accordance with AS 3580.4.1

‘Determination of Sulfur Dioxide — Direct-readinginstrumental method’; or

• UV DOAS operated in accordance with USEPAEquivalent Method EQSA-0495-101 ‘Opsis ModelAR 500 System, open path (long path) ambient airmonitoring system configured for measuring SO

2’.

2.7 Dust Deposition (fallout)2.7.1 Recommended methodThe recommended technique for routine monitoring isfallout bottles in accordance with AS 3580.10.1‘Determination of particulates — Deposited matter —Gravimetric method’.

2.8 Total suspended particulates (TSP)2.8.1 Siting considerationsThe sampler should be sited in accordance with theguideline in Australian Standard AS 2922 ‘Guide for Sitingof Sampling Units’.

In addition, it is especially important to avoid siting nearunsealed roads, unless the monitoring is to assess dustfrom roads.

The surface under the instrument should not be dusty,especially if the fan outlet is downwards. Whereverpossible, instruments should have the fan outlet deliveredthrough a pipe away from the ground and with suchvelocity and direction as to restrict the possibility of theexhaust being re-sampled under normal prevailing winds.

2.8.2 Recommended methodsThe technique recommended for routine air qualitymonitoring is high-volume sampling (HVS) with instrumentsdesignated by the USEPA and operated in accordancewith AS 2724.3 ‘Determination of total suspendedparticulates (TSP) — high-volume sampler gravimetricmethod’.

Where continuous or daily sampling and analysis arerequired, the recommended technique is the taperedelement oscillating microbalance (TEOM), operated inaccordance with USEPA Equivalent Method EQPM-1090-079, ‘Rupprecht and Patashnick TEOM Series 1400 and1400A PM

10 Monitor’, modified to allow for use of a

size-selective TSP inlet.

2.8.3 Difficulties likely to be encounteredWhen using HVS equipment, the following points shouldbe noted.• Ensure the timer is set to begin at the appointed time

(midnight) and operate for 24 hours and that it is set torun on the appointed day. This seems a simple task butis often overlooked or done incorrectly.


• The apparatus is sited and operated outside in theelements and may have to be serviced in the wet.On delivery it should be checked for electrical safetyand to ensure that the earthing is effective. Ensure theelectrical outlet is properly earthed. The safety of theinstrument is not only important for the operator butalso for anyone else when it is unattended. The HVSshould only be operated when connected through aearth leakage protection unit at the power outlet(not the sampler).

• Checks must be periodically made to ensure there areno leaks in the flow system. Blanking off the filter holderwith a non-porous sheet should reduce flow to zero.This check should be short to protect the motor fromoverheating. Ensure the filter is carefully fitted into thefilter holder to prevent air from by-passing the filter.Check the filter after use to ensure there is anuninterrupted white band of filter around the usedportion of the filter and that the filter has not torn.

• Regularly check the gable housing to ensure it is notdistorted, especially where it forms the lateral clearancearea. This should also be checked whenever thesampler is re-sited.

• Under excessive dust loading, ensure the fan motorhas the ability to provide continuous sampling withinthe requirements of the standard. If flow drops belowthe limit, the filter may have to be replaced and a newfilter used to cover a 24-hour period. Filter blockagemay occur, not only because of excessive dust loadingsbut also because of very fine particles, or particleshaving certain properties that result in blinding the filter,or as a result of a damp filter under conditions of 100%humidity. Heavy duty pumps driven by induction motorstend to have a greater capacity to reduce the problemsassociated with filter blinding.

• A major service requirement that occurs with normalbrush-type motors is the regular replacement ofbrushes and service on the commutator. The excessivewear is due to the high rotating speed of the motors.Wearing of the carbon in the brushes and the copperin the commutator can also cause re-entrainment ofthese elements if the exhausted air is re-sampled.The use of induction motors overcomes difficultiesassociated with the brushes and commutator in termsof regular replacement and also of the carbon andcopper particles and is highly recommended forsamplers that are used regularly.

• Flow calibration should be carried out regularly asdetailed in the standard and flow calibration and flowreadings should not be attempted until the sampler haswarmed up after at least five minutes’ operation andshould be carried out under very low wind conditions.Flow control devices are many and varied but care mustbe taken to ensure they maintain their efficiency andaccuracy over the working life of the instrument.

• In monitoring for TSP alone, glass fibre filters areadequate for normal use. Frequently, however, theparticulate matter collected is subject to further analysis.This is normally the case in urban areas where leadand sometimes other heavy metals are determined.In a number of other cases, additional analysis suchas sulfate or polycyclic aromatic hydrocarbon (PAH)is carried out. Chemical analysis may require specialchoices for filter material. Where lead analysis is to beconducted, the filters must have a consistently low leadcontent. PAH analysis requires low organic content inthe filters. Sulfate analysis generally requires teflon orteflon coated filters.

2.9 Particulate Matter withAerodynamic Diameter Less Than10 µ µ µ µ µm (PM10)

2.9.1 Siting considerationsThe sampler should be sited in accordance with theguideline in Australian Standard AS 2922 ‘Guide for Sitingof Sampling Units’.


The surface under the instrument should not be dusty,especially if the fan outlet is downwards. Whereverpossible, instruments should have the fan outlet deliveredthrough a pipe away from the ground and with suchvelocity and direction so as to restrict the possibility of theexhaust being re-sampled under normal prevailing winds.

2.9.2 MethodsMethods available include:• HVS using a size-selective inlet and gravimetric

analysis;• tapered element oscillating microbalance (TEOM); and• dichotomous sampler — gravimetric method.

2.9.3 Factors affecting method choiceWhen inhaled, particulate matter with an equivalentaerodynamic diameter of less than 10 µm (PM10) canresult in health implications from short-term and long-termexposures. The USEPA has a 24-hour standard and anannual standard, but there are no NHMRC goals for PM

10.

As the standard used mostly for assessment is the one dayor an annual average, continuous sampling is not required.However, for trend analysis and relation of peak readingsto meteorological influences or industrial plant emissionsupsets, the continuous output offered by the TEOM ispreferred over other methods.

The size-selective HVS is widely used for batchmeasurements of PM

10 , and is the least expensive

instrument. It has the benefit that the mass of collectedparticles is large and further analyses are easily performedby traditional techniques. The disadvantage of this methodis that it is a batch method, requires manual attentionfor every sample and does not provide information onshort-term trends.

The dichotomous sampler is a batch process and requiresmanual intervention between samples. It is expensive,and the filters require very careful handling and specialisedanalysis techniques, including the use of a microbalanceand anti static procedures.

In routine sampling, most PM10 measurements areconducted by HVS techniques according to AS 3580.9.6‘Ambient air-Particulate matter — Determination ofsuspended particulate matter — PM10 high-volume samplerwith size-selective inlet — Gravimetric method’, especiallywhere the sample will be used for further analysis.

The TEOM is much newer technology, rapidly findingits way into the market and can provide real time,almost continuous, records of mass concentration.The disadvantages are that it is the most expensivemethod and requires an expensive optional attachment,the automated cartridge collection unit (ACCU), to providesample collection if further chemical analysis of theparticles is required.


Where continuous measurements for PM10 are required,TEOMs are becoming the method of choice. In many casesTEOMs are replacing traditional HVSs. A TEOM optionalattachment, the ACCU, provides for collection of particlesfor subsequent analysis.

2.9.4 Recommended methodsThe technique recommended for routine air qualitymonitoring, where continuous or daily analysis is notrequired, is HVS using size-selective inlets and operatedin accordance with AS 3580.9.6 ‘Determination ofsuspended particulate matter — PM10 high-volumesampler with size-selective inlet — Gravimetric method’.

Where continuous or daily sampling and analysis are

required, the recommended technique is TEOM operatedin accordance with USEPA Equivalent Method EQPM-1090-079, ‘Rupprecht and Patashnick TEOM Series1400 and 1400A PM

10 Monitor’.

2.9.5 Difficulties likely to be encounteredThe HVS is required to draw 1.13 m3/minute through afilter with minimum variation under all load conditions for24-hour periods. Under these conditions, some samplershave been found lacking. Before selecting such a sampler,it is wise to ensure the instrument has the capacity to meetthis requirement under all conditions.

Stability of flow is well engineered in dichotomoussamplers and in the TEOM, but care should be exercisedfor HVS that the instrument selected can maintain stableflow under all conditions.

As mentioned above, HVS techniques permit subsequentanalysis of collected matter, but dichotomous samplersrequire selected techniques and TEOMs are not designedfor simple analysis of collected particles unless the ACCUoption is used.

Very high ambient temperature can diminish theperformance of HVS. Because the instrument operatesin ambient conditions, excessive temperatures candiminish performance of electronic parts such as flowcontrol. Under conditions of 35oC and very high dustloading, the plumbing ducts have been known to collapse.

The sample air in the TEOM is maintained at 50oCand this results in a discrepancy when compared withtraditional techniques. This discrepancy is due to the factthat salts and some other compounds contained on thefilter absorb moisture from the air. At different temperaturesand humidities, masses of certain compounds will change.As the temperature and humidity of the gravimetric analysisof particles collected by TEOM and HVS techniques aredifferent, there will be an inherent difference in thegravimetric analysis. This difference is generally small.

2.10 Fine Particles2.10.1 Siting considerationsThe sampler should be sited in accordance with theguideline in Australian Standard AS 2922 ‘Guide for Sitingof Sampling Units’.


The surface under the instrument should not be dusty,especially if the fan outlet is downwards. Whereverpossible, instruments should have the fan outlet deliveredthrough a pipe away from the ground and with suchvelocity and direction so as to restrict the possibility of theexhaust being re-sampled under normal prevailing winds.

2.10.2 MethodsMethods available include:• dichotomous sampler — gravimetric method;• TEOM; and• ASP low-volume cyclonic sampler.

2.10.3 Factors affecting method choiceFine particles, the particle size fraction less than 2.5 µmin equivalent aerodynamic diameter, are respirable andare inhaled into the pulmonary region. They are commonlyreferred to as PM2. 5 and consist of secondary particlesformed from chemical reaction (gas to particle conversion),combustion particles and recondensed organic and metalvapours. The mass collected is relatively small andtechniques must be precise.

None of the methods collects sufficient matter for traditionalanalysis. The collected matter from the dichotomoussampler, the ASP low-volume cyclonic sampler and theTEOM with an ACCU option can, however, be used fornon-destructive ion-beam analysis. The use of PIXE,particle-induced gamma ray emission (PIGME) and particleelastic scattering analysis (PESA) enables analysis for23 elements with very low detection limits.

Particle concentrations on a 24-hour average basis can bedetected down to 1 mg/m3 using the dichotomous sampler,and 150 ng/m3 for the ASP method. TEOM can detect levelsbelow 1 mg/m3.

Dichotomous sampling is seldom used in Australia. Inroutine sampling most PM2.5 measurements, especiallywhere the sample will be used for further analysis, areconducted using ASP low-volume cyclonic samplers.

2.10.4 Recommended methodsTechniques recommended for routine air qualitymonitoring are:• TEOMs operated in accordance with USEPA Equivalent

Method EQPM-1090-079, ‘Rupprecht and PatashnickTEOM Series 1400 and 1400A PM10 Monitor’, modifiedto allow for use of a size-selective PM

2.5 inlet; or

• ASP low-volume cyclonic sampler, using the methoddescribed by Cohen et al. (Cohen D.D., Noorman J.T.,Garton D.B., Stelcer E., Bailey G.M., Johnson E.P.,Ferrari L., Rothwell R., Banks J., Crisp P.T. and Hyde R.‘Chemical Analysis of Fine Aerosol Particles within 200km of Sydney: Introduction to the ASP Aerosol Study’.Clean Air Vol 27 No. 1 1993).

Where continuous or daily sampling is required, TEOMsare the preferred choice. If the collected sample is neededfor further analysis, the ACCU option must be fitted.

2.11 Visibility2.11.1 MethodsMethods available include:• visual observations; and• nephelometry.

2.11.2 Factors affecting method choiceFrequently, the agreement between nephelometry andvisual observations is poor, and this is not surprising.Visual observations are developed to detect the visualimpairment caused by fog and mist and, to a lesser extent,visual impairment due to fine particles in the air.Conversely, integrating nephelometry, for air qualitypurposes, takes precautions to remove light scattering dueto fog and mist and is designed primarily to detect lightscattering due to fine particles.


Community perception of air pollution usually relatesto visibility, and fogs and mist can influence estimates.Continuous measurements relying on instrumentalmethods provide reliable output, but this does not alwayscoincide with community perception.

On days when fog, rain or mist is evident, communityperception based on observation will indicate much lowervisibilities than indicated by nephelometry.

Visual observation cannot be used in the dark, and thislimits its use. The integrating nephelometer operatescontinuously.

Visual observations do not estimate fine particle mass.Particles of size fraction approaching the wavelength ofvisible light scatter light most effectively. Many studieshave shown a good correlation between integratingnephelometry and fine particle mass such as PM

2.5.

Visibility observations are not used in Australia in ascientific manner for air quality assessment.

Nephelometers have been in use in Australia for air qualitystudies for some time.

2.11.3 Recommended methodThe technique recommended for routine air qualitymonitoring is the integrating nephelometer, operated inaccordance with AS 2724.4 ‘Ambient Air — Particulatematter Part 4 — Determination of light scattering —Integrating nephelometer method’.

2.11.4 Difficulties likely to be encounteredVarious models of integrating nephelometer are availablein Australia. The instruments have a different spectralconfiguration and have different wavelength responses.AS 2724.4 ‘Ambient Air-Particulate matter Part 4 —Determination of light scattering — Integratingnephelometer method’ gives calibration factors to beapplied to these instruments to improve equivalence ofreadings. However, studies comparing outputs from twodifferent instruments, even when using the appropriatecalibration values, have shown the outputs vary by factorsranging from 1.06 to 1.24.

2.12 Open path spectrometryIn addition to the air quality methods described above,open path spectrometers have come into use in recenttimes for monitoring a number of parameters.

Traditional air quality monitoring samples the air at a singlepoint and relies on air movement to achieve a sampleaverage in an air parcel. Open path sampling determinesan average concentration over the path of interest, usuallybetween the light source (of a spectrometer) and areceiver. The open path length is normally over hundredsof metres.

2.12.1 MethodsMethods available include:• Fourier transform infra-red (FTIR); and• UV differential optical absorption spectrometer (DOAS).

2.12.2 Factors affecting method choiceFourier transform infra-red (FTIR) instruments can measurea greater range of gases but have a higher detection limit,tend to be harder to use, and require more operatorattention, and they have not become widely used forroutine ambient air quality monitoring. UV DOASinstruments on the other hand, can measure a somewhatreduced range of gases but offer substantially lowerdetection limits, are easier to use, and require lessmaintenance.

UV DOAS has the ability to measure many species, bothorganic and inorganic, continuously and simultaneously,and report up to six or more contaminant concentrationsat the same time. Some models can also measure overmore than one path at the same time. They can providediscrete continuous data for each path and survey an areaor measure along several perimeters of a site.

UV DOAS instruments, when compared with fixed pointmonitors, have advantages, including:• capacity to measure a whole range of organic and

inorganic contaminants, many simultaneously;• capacity to operate with a minimum of service and

calibration intervention;• potential for low operating costs;• measurement of contaminants in situ, which eliminates

the potential loss of reactive contaminant gases onsurfaces within the sampling system;

• spatial average measurements, which are not subjectto local fluctuations; and

• ability to operate in locations not always possible withfixed point samplers (such as over inaccessible terrain,water or property, or across a highly trafficked region).

The instrument type most widely used for routine open pathair quality monitoring is the UV DOAS.

2.12.3 Recommended methodUV DOAS operated in accordance with a USEPAequivalent methodology is a recommended technique forroutine air quality monitoring.

2.12.4 Difficulties likely to be encounteredSiting of UV DOAS instruments is important andshould comply with the requirements found in AS 2922‘Guide for siting of sampling units’ when used for traditionalmonitoring. Open path instruments have some benefitshere as they provide average values over a path lengthand tend not to suffer from some of the interferences dueto sources or sinks in the close proximity of fixed pointmonitors. Conversely, the instrument components, bothtransmitter and receiver, must be securely fixed to theirsupporting surface and aligned, so the beam of lightremains on target during long periods of monitoringunder all kinds of weather conditions.

UV DOAS instruments have a comparatively high initialpurchase price, and initial setting up and instrumentalignment and non-routine service or maintenance aredifficult and rely on factory technicians.

2.13 Recommended air quality testmethods — summary

The recommended air quality test methods for the specificatmospheric contaminants described in Section 2 aresummarised in Table 1.


PARAMETER RECOMMENDED TEST METHOD SOURCE DOCUMENT

AS 3580.7.1

AS 2800 using the HVS techniquesAS 2724.3 or AS 3580.9.6

1. AS 3580.5.1 or

2. USEPA Equivalent MethodEQNA-0495-102

1. AS3580.61 or

2. USEPA Equivalent MethodEQOA-0495-103

1. AS 2427 or AS 3580.9.6 with Method720A Suppressed AnionChromatography in Methods of AirSampling and Analysis, 3rd edit. ofIntersociety Committee AWMA, ACS,AIChE, APWA, ASME, AOAC, HPS, ISA1988. Ed. James P Lodge Jr. or

2. Cohen D.D., Noorman J.T., Garton D.B.,Stelcer E., Bailey G.M., Johnson E.P.,Ferrari L., Rothwell R., Banks J., CrispP.T. and Hyde R. ‘Chemical Analysis ofFine Aerosol Particles within 200 km ofSydney: Introduction to the ASP AerosolStudy’. Clean Air Vol 27 No. 1, 1993

1. AS 3580.4.1 or

2. USEPA Equivalent MethodEQSA-0495-101

AS 3580.10.1

1. AS 2724.3

2. Modified USEPA Equivalent MethodEQPM-1090-079

1. AS 3580.9.6

2. USEPA Equivalent MethodEQPM-1090-079

1. Modified USEPA Equivalent MethodEQPM-1090-079

2. Cohen D.D., Noorman J.T., Garton D.B.,Stelcer E., Bailey G.M., Johnson E.P.,Ferrari L., Rothwell R., Banks J., CrispP.T. and Hyde R. ‘Chemical Analysis ofFine Aerosol Particles within 200 km ofSydney: Introduction to the ASP AerosolStudy’. Clean Air Vol 27 No. 1, 1993

AS 2724.4

GFC

HVS collection with AAS or ICP analysis

1. Chemiluminescence or

2. UV DOAS

1. UV absorption or

2. UV DOAS

1. HVS collection with ion chromatography or

2. Low-volume sampling followed by ion beamanalysis (if no droplets present)

1. Fluorescence or

2. UV DOAS

Fallout bottles

1. HVS or

2. TEOM for continuous sampling

1. HVS with size-selective inlet for batchsampling or

2. TEOM for continuous sampling

1. TEOM or

2. Low-volume sampling

Nephelometry

Carbon monoxide

Lead

Oxides of Nitrogen(NO & NO

2)

Ozone

Sulfates

Sulfur dioxide

Dust deposition(fallout)

TSP

PM10

Fine particles(PM

2.5)

Visibility

Table 1. Summary of recommended air quality methods


3 Emission testing— general issues

3.1 General requirements forsource testing

The following sections describe the requirements fora successful source emission testing program.

3.1.1 StaffTechnical staff must be trained in the emission testprocedures to be followed, and be aware of conditionsthat will invalidate results.

As in all fields of analytical chemistry, source testingtechnical staff must be constantly supervised until theyhave attained a high level of expertise.

Routine assessment/auditing should then be conductedto ensure that this expertise is maintained.

3.1.2 MethodologyValidated source emission test methods are publishedby Standards Australia, British Standards, AmericanSociety for Testing & Materials (ASTM), InternationalOrganization for Standardization (ISO), USEPA and anumber of Australian State regulatory authorities.

These methods should be followed wherever possible.Procedures must also be in place for obtaining test methodrevisions and updates for all methods used.

In many circumstances, more than one method will beavailable. The appropriate method should be selectedbased on an assessment of the test conditions for aparticular source:• sampling platform access;• sampling plane diameter;• exhaust gas temperature, moisture content and velocity;• anticipated atmospheric contaminant concentration;• limit of detection required; and• specific regulatory authority requirements.

3.1.3 Equipment calibrationSource testing equipment must be calibrated on a regularbasis to ensure that reliable emission test data is obtained.The calibrations must be traceable to an externalrecognised standard.

Equipment requiring calibration includes pitot tubes,manometers, gas meters (volume and flow), anemometers,thermometers and continuous emission monitoringanalysers. It is essential that current calibration data fortesting equipment is subsequently incorporated intoemission test calculations. Too often, this step is neglected.

Laboratory apparatus used in the processing and analysisof source test samples must also be suitably calibrated.This includes ovens, balances, spectrophotometers,and chromatographs.

Other important areas of quality management include theuse of field and laboratory blanks.

For continuous emission monitors, total system calibrationshould be carried out on initial set-up, whenever majormaintenance or modification is carried out, and at leastannually. It is not just the analyser that needs calibration,but the full sample train. Validation checks must also bemade against a reference method, particularly wherecalibration of the complete system is impractical, suchas for open path spectrometry methods. Results from thecontinuous monitoring system should not differ fromreference method results by more than 10%.

3.1.4 FacilitiesAppropriate site and laboratory facilities must be availablefor a successful emission monitoring program.

This includes adequate staff facilities and housing forsampling and laboratory equipment.

A safe and secure storage area must be available forsource emission test samples. Possible contaminationsources must be evaluated and controlled.

3.1.5 DocumentationInterpretation of emission test data should be handledcarefully, giving due regard to the errors involved in bothvolumetric flow determination and atmosphericcontaminant concentrations.

All calculations and data transfers should be checkedby an appropriate checking officer.

The final report should include sufficient information toenable an independent authority to check that the testconditions were appropriate and that the calculationsare consistent.

This information should include:• time and date of test;• a description of the equipment under test and its

operating parameters;• test methods used and expected accuracies;• measured parameters such as exhaust gas velocity,

flow rate, temperature and moisture content,contaminant concentration and mass rate of emission;

• calculation basis (dry gas or wet gas basis; standardtemperature and pressure); and

• a description of the sampling plane location andsampling plane diameter (in the case of particulatemeasurement).

The test samples must have a unique description/numberto enable traceability through the final test report,laboratory workbooks, computer information managementsystems and field data sheets, if required.

All documentation must be retained and appropriately filed.

3.1.6 Quality managementAll emission testing programs and activities are to beincorporated into the quality management system. Effectiveapplication of the quality management system will provideoperational and management tools to ensure that theprogram requirements are achieved with consistency,accuracy and reliability.

The developed QMS is to be based on the requirementsof the quality standard AS/NZS ISO 9002 ‘Quality Systems— Model for quality assurance in production, installationand servicing’, or similar. The implemented operating andmaintenance procedures for the emission testing programshould cover the appropriate and relevant elements of theabove quality standard.

3.1.7 Laboratory accreditationThe Federal Government’s response to the Report ofCommittee of Enquiry into Australia’s Standards andConformance Infrastructure clearly defines NATA asthe nationally recognised laboratory accreditation body.

Laboratory accreditation describes a process of givingformal recognition of the testing laboratory’s competencein carrying out specific tests or types of tests. This process,includes, but is not limited to, a review of the qualitymanagement system.


Air testing laboratories come under the field of chemicaltesting. NATA principally assesses laboratories seekingchemical testing accreditation/registration against NATAGeneral Requirements for Registration (based onInternational Organization for Standardisation (ISO) ISO/IEC Guide 25 ‘General Requirements for the Competenceof Calibration and Testing Laboratories’), NATA ChemicalTesting Requirements for Registration, the LaboratoryQuality Manual and the specific test methods proposed.

The system elements assessed include:• documentation of sampling and analytical methods;• documentation of quality management system;• provision of adequate accommodation and storage;• calibration, maintenance and commissioning of

equipment; and• record keeping and report production.

The technical competency elements assessed include:• qualifications and experience of staff;• competence of management;• appropriateness of test methods and laboratory

adherence to them;• the suitability, and correct use of, equipment;• appropriateness of, and use of, reference materials;• evaluation of quality control data;• complete and correct recording and reporting; and• the suitability and monitoring of the laboratory

environment.

It is important to recognise that a laboratory’s accreditationdoes not cover all source emission test methods andatmospheric contaminants. The atmospheric contaminantsand the test methods for which accreditation has beengiven are listed in the laboratory’s registration.

3.1.8 Common sources of errorThe major areas where the quality of test data can becompromised are as follows:• sample collection (sample train leaks, dewpoint

problems, contamination, spillage, incorrect labelling);• data transfers (from field sheets to workbooks/

spreadsheets; to reports);• calculation errors; and• upset process operating conditions (shutdown,

unstable conditions).

Sample collection issues are best dealt with through stafftraining and adherence to test methods and standardoperating procedures.

Data transfer errors are difficult to detect, but are aspecific area that the laboratory manager or authorisedrepresentative should carefully check before releasingthe report.

Calculation errors can be essentially eliminated throughthe use of standard calculation sheets or spreadsheets.Spreadsheets should be checked for formula errors byinput of a standard set of data with known results.

An industrial process should be assessed throughout anemission monitoring program to ensure that operatingconditions have not changed or the process shut down.

3.2 Sampling plane selection forparticulate sampling

Australian Standard AS 4323.1 ‘Stationary SourceEmissions; Method 1: Selection of Sampling Positions’contains a detailed description of the factors which mustbe considered when selecting an appropriate samplingplane. As a general guide, the plane should be greaterthan 2–3 diameters (or hydraulic diameters in the case

of rectangular flues) upstream from a flow disturbance,and 6–8 diameters downstream. A flow disturbancecould be a bend, junction, damper, fan or change influe cross section.

Emission monitoring program data would suggest that adistance of 8 diameters downstream from an axial fan orcyclone is unlikely to be sufficient to enable compliancewith the cyclonic flow criteria. Experience would suggestthat a distance of 15 diameters may still be inadequate inthese circumstances. The installation of flow straightenersshould be considered where tests involving axial fans andcyclones are required.

Other factors that must be considered when selectinga sampling plane are listed below.

SedimentationIf particulate matter emission tests are proposed inhorizontal ducts, the sampling plane should not be morethan 10 diameters from a flow disturbance (such as abend or a change in duct diameter or shape) to reducethe potential impact of sedimentation. Emission testsshould not be conducted in ducts that contain dustdeposits, due to the difficulty in determining the actualsampling plane cross sectional area, and the highprobability that settled dust will be disturbed by thesampling equipment, resulting in sample contamination.

Available safe accessSuitable access may already be to a location on theprocess building roof or an internal process walkway.

Axis of stackThe sampling plane must be at right angles to the axis ofthe stack or duct being measured.

Services availableA suitable power supply (240 V, 10/15 A or three-phasepower 415 V) will be required. A residual current devicemust be located at the power outlet. It is preferable to havethe power outlet located at the sampling platform,preventing the use of long extension leads. Compressedair and town water supply may also be required for someemission test methods. Lighting may also be necessary iftesting occurs outside daylight hours.

Work platformA sampling platform may already be available. This willstrongly influence the decision regarding the location ofthe sampling plane, despite compliance or non-compliancewith the other stated criteria.

Unobstructed distanceEnsure that there is a distance equal to the diameter of thestack plus 1 m along the line of the sampling traverse, toenable the sampling probe to be inserted and withdrawn.

The reality of industrial process duct and flue arrangementsis that it is extremely difficult to satisfy all of the abovecriteria. A compromise location is therefore invariablyrequired. The criteria relating to flow direction andminimum velocity are considered to be the most critical,followed closely by that for cyclonic flow.

3.3 Sampling point requirementsFor particulate sampling, the number and location ofsampling points on eachsampling traverse depends on:• duct shape (circular/rectangular);• sampling plane area; and• sampling plane suitability.


Tables 3 and 4 of Australian Standard AS 4323.1‘Stationary Source Emissions; Method 1: Selection ofSampling Positions’ define the number of sampling pointsrequired for ducts of circular and rectangular cross sectionrespectively. The values in these tables are for idealsampling planes that comply with the assessment criteriacontained in the standard. Where this is not the case, thenumber of sampling ports should be increased to allow fornon-ideal conditions. Table 2 of AS 4323.1 contains factorsthat can be applied to increase the number of points basedon the distances downstream and upstream from flowdisturbances. It should be recognised, however, that in anumber of circumstances applying these factors will notsignificantly alter the accuracy of the test procedure. Forexample, the error introduced by sampling close to axialfan and cyclone exhausts will not be compensated for bysampling at a greater number of points.

Sample ports must be fitted with sockets with internalthreads that allow gas-tight coupling to sampling probes.Size and design requirements of the socket depends onthe probe needed for the parameter to be measured. G4/100 sockets (4” British Standard Pipe (BSP)) are generallysatisfactory for particulate matter sampling probes. 1” BSPsockets are generally satisfactory for gaseous emissionsampling probes.

3.4 Work platform requirementsCherry pickers are not normally acceptable as workplatforms. There is inadequate space for samplingequipment, and the movement of the bucket due to wind,or sampling personnel movement, makes it almostimpossible to correctly level inclined manometers,and obtain velocity pressure measurements.

The work platform should have:• a minimum work area of 6 sq.m;• safety railings at heights of 0.5 m and 1 m above

the floor level;• a kick plate;• access to all access holes;• typical minimum width of 1–1.25 m for the majority

of stacks;• a platform floor approximately 1.35 m below the

sampling ports, to prevent the sampling probe foulingon the safety railings;

• no large openings in the platform floor;• an equipment rail for the mounting of the sampling train,

if required; and• safe access for equipment and staff via a walkway,

stairway or a fixed ladder.

3.5 Health and safety considerationsMany hazards are associated with conducting sourceemission monitoring programs. Associated risks must beminimised or eliminated through careful planning, stafftraining and the use of appropriate equipment.

All staff should undergo safety training prior to commencingsite work. Training courses may be internal or external,but most focus on the particular hazards associated withsource emission testing.

Some factors that should be considered in a trainingprogram are listed below.

Site-specific safety trainingMany companies require contractors to undergo safetyinduction prior to allowing site access. Client safetyrequirements must be adhered to under all conditions.If not included in the induction process, the followinginformation should be requested:• hazards associated with the particular process to

be monitored;

• general site hazards;• work platform ladder access requirements;• safety shower and eye wash station locations;• first aid or medical centre location;• fire extinguisher locations and conditions under which

they should be used;• emergency exit locations;• emergency assembly locations;• designated site contact for emergency purposes;• contact phone numbers for emergency personnel;• meanings of emergency signals; and• a site map showing buildings, roadways and walkways.

Following a site safety induction, the designated siterepresentative should take the testing staff to the workplatform, indicating the preferred access route and thelocation for vehicle parking.

If testing staff consider any aspect of the requiredmonitoring program to be unsafe, they should not continuewith the program until the apparatus, ladder, walkwayor platform has been made safe. WHEN IN DOUBT,ASK FIRST.

Sunburn and skin cancer risksMost source emission tests are conducted on roofs or stackplatforms with little shade. Reflective roof surfaces increasethe potential for overexposure to the sun.

Testing staff must use a sunscreen with a minimumprotection factor of 15+, and a wide-brimmed hat tominimise the chances of suffering from sunburn, or,in the long term, skin cancer.

Source emission tests take a considerable time, typicallythree to eight hours. Sunscreen must be routinely reappliedin accordance with the manufacturer’s instructions.

Dehydration/hypothermiaSource tests occur over a considerable period of time,under a range of weather conditions. When working onelevated platforms, testers should take care to ensuresufficient drinks are available for the period of the test.Clothing should provide both a level of protection from anytesting hazards (such as high temperature equipment orexhaust gases), and be appropriate for the prevailingweather conditions.

Working at elevated heightsSource emission tests are conducted on roofs or elevatedsampling platforms. A fall can cause serious injury ordeath. Testing staff must not stand near the edge of anun-scaffolded roof, run on work platforms or climb the samesection of ladder more than one at a time.

High wind conditionsHigh wind conditions are dangerous. It should berecognised that any winds at ground level will be far moresevere on an elevated sampling platform. Where verticalaccess ladders are provided to a sampling platform, ropesshould be used to raise and lower emission monitoringequipment. The equipment may be dislodged or damagedfollowing contact with the stack or building structure underhigh wind conditions.

High temperature gases and equipment,and chemical hazardsEach staff member must be issued with personal protectiveequipment suited to hazards that may be present. Theseinclude safety glasses, hard hat or bump cap, ear plugs/earmuffs (as appropriate), respirators (selected on the basisof atmospheric contaminants likely to be present), overalls/coveralls, gloves (leather, rubber, PVC, ceramic fibre),wet weather equipment and steel capped boots.


When removing a plug or cover plate from a stack samplingport, testing staff should wear appropriate equipment, butshould also stand to one side, never in front. Particulatematter collected in the port or in the exhaust gases, and/orhigh temperature or toxic gases may be emitted at highvelocity as a result of high static pressure within the stackor duct.

Working with ducts under negative pressure presentsdifferent hazards, including the effort required to removecover plates, jamming of fingers under cover plates,and sucking in of equipment or body parts.

Chemical hazards are associated with both the sourcebeing tested and chemicals used in the sampling train.Always wear protective equipment appropriate to theknown chemical hazards, or those likely to be present.

Metal sampling probes inserted into high temperaturegas streams quickly reach the gas temperature. Alwaysuse gloves providing appropriate thermal protection whenremoving and inserting probes into gas streams aboveambient temperature. For high temperature sources,gauntlet style gloves are preferred. It should beremembered that irrespective of the material ofmanufacture, gloves provide a limited period of protectionunder high temperature conditions. Always plan theequipment and staff arrangements such that movementof high temperature equipment is conducted efficiently.

Electrical hazardsSingle phase 240 V, 10 A weatherproof power outletslocated at the sampling platform are preferred. Longextension leads can create a hazard as a result of contactwith hot stack surfaces or by traversing walkways.A portable residual current device must be located at thepower outlet. Under no circumstances should the residualcurrent device be located at the end of an extension lead.

All power cords used in emission testing must be visuallyinspected for damage, electrically checked and tagged bya registered electrician in accordance with state regulatoryrequirements. These include cords associated withextension leads, heaters, continuous emission monitoringanalysers, lighting and sampling pumps.

High voltage static charges can be built up by the actionof a fast-moving gas stream on a metallic probe. Earthingmay be required to avoid shocks from static dischargefrom the probe.

Falling objectsSampling equipment or tools may be knocked or blownoff a stack work platform under high wind conditions. Smallobjects such as screwdrivers can easily fall through meshwalkways. This is a significant hazard for testing staffworking at ground level, or for other people working inthe immediate vicinity.

The ground level area surrounding the stack or roof areamust therefore be cordoned off with appropriate signageindicating the danger due to work overhead. All testingstaff working at ground level within the isolated area mustwear hard hats.

3.6 Sample handling/chain of custodyThe most common time for emission test samples to belost, either partially or wholly, or contaminated, is duringthe initial transfer from the sampling train to the samplecontainer. The importance of this step must be emphasisedto testing staff during all phases of training. If necessary,the sampling train should be removed from the samplingplatform to an area that is dry, clean and with no air

currents. The exterior surface of the sampling train shouldbe thoroughly cleaned prior to disassembly for samplerecovery.

As an emission test sample is unlikely to remain in thepossession of the testing staff throughout the testing andanalytical stages, a chain of custody procedure is required,enabling the location and status of the sample to bedetermined at any time.

Source emission test samples are typically given a uniquesite sample number for the particular day of sampling.To avoid confusion sample containers should be labelledwith the:• date and sample period;• initials of sampling staff;• atmospheric contaminants applicable to the particular

sample;• discharge point identification number, or description

if a number is unavailable; and• site sample number.

Identification labels, if required, must be secure andlegible. Under no circumstances should any of the aboveinformation be included on the cap or lid of the samplecontainer, unless it is replicated on the body of thecontainer.

Sample containers must be leak-proof. Contamination ofthe sample from external sources should not be possibleduring transport, due to both the design of the containerand the method of sample storage or packaging.

If the sample is a liquid, the level should be marked onthe outside of the container, enabling confirmation bylaboratory receiving staff that sample loss has not occurred.If laboratory staff have concerns regarding sample integrityor contamination, this must be reported to testing staff andlaboratory management.

Where samples must be maintained at specificenvironmental conditions prior to analysis (such assemi-volatile organics) a chain of custody form must recordthe conditions at the time of sample collection and samplereceipt at the laboratory. The acceptability of theseconditions must be confirmed by the signatures of seniortesting and laboratory staff.

Samples received at the laboratory must remain in asample reception area until registered into the laboratoryrecords, preferably by testing staff. This process shouldoccur as soon as possible upon receipt. The sampleregister should include:• a unique laboratory identification number;• the site sample number;• a description of the emission source and atmospheric

contaminants monitored;• a description of the sample matrix;• the sample date;• testing staff;• the analytical procedure;• the analytical laboratory;• project number;• client name;• responsible laboratory staff member;• sign off following completion of analyses by laboratory

staff; and• sign-off by person responsible for checking calculations

and data transfers.

Where possible, data transfers should occur by computer-based systems to prevent transcription errors.


The person responsible for confirming data quality shouldcheck raw data, calculations and data transcriptions ateach stage from the field data sheets to the final report.

On the completion of analyses, the sample should beretained in a sample storage area for a minimum periodspecified by the test method, general laboratoryrequirements, or in some instances by particular clientneeds, prior to disposal. The laboratory quality systemmay therefore have to differentiate between a numberof different sample storage periods.

3.7 Report formatsA number of items must be included in emission testreports, for:• accreditation purposes;• ensuring that the client receives maximum benefit from

the data, both now and in the future; and• enabling regulatory authorities to confirm the internal

consistency of the emission test data.

The following items should be included:• reason for conducting the tests and any specific

monitoring program objectives;• date of test, time of test, client name, location of

emission source and identification number;• date of report issue and a unique report identification

number;• reference to the actual test methods and accuracies;• description of sampling trains used in the monitoring

program;• description of the sampling location, including the

approximate number of diameters to upstream anddownstream flow disturbances (the description canbe enhanced through the use of a sketch plan);

• name and contact details of the sampling laboratory,and analytical laboratory, if separate organisations;

• internal diameter of stack at the sampling plane;• average stack gas velocity;• average stack gas temperature;• stack gas molecular weight;• stack gas moisture content in %v/v;• stack gas carbon dioxide and/or oxygen contents in

%v/v if required for standardising atmosphericcontaminant concentrations;

• stack gas flow rate under actual conditions oftemperature and pressure, and on a dry gas basisat standard temperature and pressure (STP);

• atmospheric contaminant concentration (dry basis)for each determination;

• atmospheric contaminant mass rate of emissionfor each determination;

• calibration and validation data;• plant description and process operating conditions

prevailing during the emission test period;• discussion of results including a clear statement of

compliance or non-compliance with the test methodused;

• identification of any process operating conditions orsampling conditions that may have influenced theemission test data accuracy, or representativeness ofnormal process operating conditions;

• statement of conditions governing reproduction of thedocument; and

• signature of the senior test personnel and laboratorymanager (or approved NATA signatory if laboratoryaccreditation is held).

3.8 Equipment calibrationMonitoring equipment used for air emission testing mustbe calibrated on a routine basis to ensure data accuracy.Calibration factors must also be used, where required,during sampling programs. For example, manometer andgas meter calibration factors should be used in calculatingisokinetic sampling rates.

National Association of Testing Authorities (NATA)equipment requirements and calibration intervals arecontained in the publication ‘Chemical Terms ofRegistration — 1993’ for stack emission sampling andanalytical equipment. These criteria are considered tobe the maxima, and rely on the completion of laboratoryinternal checks during the intervening period, andimmediate calibration of equipment if overloading ormishandling occurs.

Particular aspects of calibration requirements for individualequipment items are discussed in the followingsubsections.

3.8.1 AnemometersHot wire and vane anemometers require full calibrationby a NATA-registered laboratory, over the measurementrange, every two years. The requirement for NATAendorsement currently limits the calibration laboratoryto Commonwealth Scientific and Industrial ResearchOrganisation (CSIRO) Division of Atmospheric Research,Aspendale, Victoria.

3.8.2 BarometersAneroid barometers initially require full calibrationby a NATA-registered laboratory.

Single point calibrations, every subsequent periodof six months, are required against a known standard.The Bureau of Meteorology will provide this service.

3.8.3 Continuous emission monitoring analysersBefore use, a span and zero check must be conducted oncontinuous emission monitoring analysers. The followingcalibration results should be recorded;• analyser readings before and after calibration;• instrument set points (for example, potentiometer

readings, voltages); and• calibration gas concentration and reference number.

If the instruments are to remain in the field during amonitoring program conducted on a single source,the span and zero check should be repeated everyseven days.

The span gas concentration should be in the range75–90% of analyser full scale or, for multi-rangeinstruments, 75–90% of the range being used.

A complete analyser calibration is required every sixmonths. This is aimed at confirming the linearity of theinstrument response by recording the readings for anumber of calibration gas standards.

The calibration requirements will depend on theinstrument type.• For non-dispersive infra-red (NDIR) analysers a

six-point and zero check is required. Recommendedvalues are 15%, 30%, 45%, 60%, 75% and 90%of full-scale deflection. For ultraviolet,chemiluminescence, fluorescence, electrochemical,thermal conductivity, paramagnetic and zirconium oxideanalysers, a three-point and zero check is required.Recommended values are 30%, 60% and 90% offull-scale deflection.


For multi-point calibrations, analyser settings should notbe adjusted following the initial 90% span and zero check.The analyser readings for the intermediate points aresimply recorded. To prevent the need for a large numberof certified gas standards, it is appropriate that the highstandard is diluted to achieve the required concentrationusing a dynamic dilution system, mass flow controllers orfixed orifice systems. It should also be recognised that,whichever system is used, the dilution ratio achievedmust also be confirmed through flow rate calibration.

No acceptance and rejection criteria are specified forinstrument linearity. A suggested acceptance criteria isthat the correlation coefficient from the linear regressionanalysis should exceed 0.99.

3.8.4 Gas metersDue to the expense of wet gas meters, the majority ofemission testing is conducted using dry gas meters.

Calibration is required, as a minimum, every two years.For meters with high use, a shorter period should beconsidered, due to the corrosive nature of many emissionsources, and the effect this can have on the rubberdiaphragms and meter linkages. Any incident that couldeffect the calibration (for example, damage, shock orblockage) should be noted and the calibration checkedbefore the gas meter is returned to service.

Due to the high cost of calibrations, it is worth consideringmaintaining one gas meter as a reference standard, stillwith a two-yearly calibration period, against which workinggas meters are calibrated. The working and referencegas meters are connected in series with both readingsrecorded over the working flow-rate range. It is essentialthat the calibration factor for the reference meter, and thepressure at which the first meter in the train operates areused in subsequent calculations.

Under no circumstances should a reference gas meterbe used in the field.

3.8.5 ManometersBoth electronic and inclined liquid in glass manometersare used for velocity and static pressure determinationsduring point source emission sampling programs.

Calibration periods are ten years for a referencemanometer and three years for a working manometer.Under no circumstances should a reference manometerbe used in the field.

The specific gravity of the manometer fluid must also bedetermined prior to calibration of the manometer, andwhenever a new batch of manometer fluid is purchased.

The manometer calibration should be conducted at aminimum of three pressures covering each manometerrange or inclined tube position.

Again, to reduce calibration costs, it is acceptable tocalibrate the working manometers against the referencemanometer if a stable pressure can be equally applied tothe manometer fluid reservoirs of each manometer,and the respective readings recorded.

3.8.6 NozzlesThe internal diameter of nozzles used in the conduct ofisokinetic emission tests must be measured by micrometer,and recorded. The nozzles must be protected in storageand use to prevent damage to the end of the nozzle.The diameter must be reconfirmed if any repair is required.

3.8.7 Pitot tubesThe NATA Chemical Terms of Registration do notspecifically distinguish between L and S type pitot tubes.

The initial calibration check referred to involves adimensional compliance evaluation against therequirements of British Standard BS 1042, Section 2.1,Annex A. This only contains dimensional criteria forhemispherical and ellipsoidal head L-type pitot tubes.

No further calibration is required for L-type pitot tubes;however, periodic checks against a reference L-type pitottube are strongly recommended.

S-type pitot tubes should be constructed in accordancewith USEPA Method 2 ‘Determination of Stack Gas Velocityand Volumetric Flow Rate (Type S Pitot Tube). AlthoughUSEPA Method 2 suggests that a S-type pitot tubeconstructed in accordance with the method criteria hasa coefficient of 0.84, this is not considered sufficient.Calibration of S-type pitot tubes against a referenceL-type pitot tube is required to establish the actual pitottube coefficient.

Before use, all pitot tubes should be inspected to ensurethat there is no damage to the tip or blockage to the totalor static pressure holes.

3.8.8 Reference gas mixturesReference gas mixtures should by certified by a NATA-registered laboratory. The certification should include adate within which the certification is valid, usually two tofour years. Reference gas mixtures with certifications thatare out-of-date or do not include a ‘use-by’ date shouldnot be used for calibration purposes.

3.8.9 RotametersThe specified calibration periods are three years for areference rotameter and, theoretically, on-use for a workingrotameter. Under no circumstances should a referencerotameter be used in the field.

The current NATA requirements are considered somewhatimpractical in application.

A full calibration over the entire working range isrecommended against a calibrated reference (that is,reference gas meter or soap bubble meter). For rotametersused in atmospheric contaminant sampling trains, a gasmeter is also normally present. Comparison of therotameter reading against the calculated flow rate basedon gas meter readings is considered adequate verificationof the rotameter calibration in use.

For rotameters used in dynamic dilution apparatus,an annual calibration over the working range againsta calibrated reference is considered adequate.

If the rotameters are disassembled and reassembled forcleaning purposes, or parts are replaced or interchanged,a full calibration should be conducted prior to use.

3.8.10 Stop watches/timing devicesStop watches or alternative timing devices must becompared against the Telstra time signals over a minimumperiod of ten minutes every three months and the resultsrecorded.

3.8.11 ThermocouplesType K thermocouples and electronic thermometersare often used in emission sampling programs.


Reference thermocouples require full calibration by aNATA-registered laboratory over the working range everythree years. Working thermocouples require calibration ata single point in the working range against a referencethermocouple or thermometer every six months. This isnormally conducted in boiling water.

Under no circumstances should a reference thermocouplebe used in the field.

3.8.12 ThermometersReference liquid in glass thermometers require fullcalibration by a NATA-registered laboratory over theworking range every ten years.

Reference liquid in glass thermometers require an icepoint check every six months.

Under no circumstances should a reference thermometerbe used in the field.

Working liquid in glass thermometers require an initialcalibration against a reference thermometer at sufficientpoints to cover the working range.

Working liquid in glass thermometers require 6 monthlycalibration against a reference thermometer at the icepoint and at one point within the working range, typicallyboiling water.

4 Atmospheric contaminantemission test methods

4.1 Opacity4.1.1 MethodsMethods available include:• British Standard BS 2742 ‘Use of the Ringelmann and

Miniature Smoke Charts’;• USEPA Method 9 ‘Visual Determination of the Opacity

of Emissions From Stationary Sources’;• USEPA Method 9A ‘Determination of the Opacity of

Emissions From Stationary Sources Remotely by Lidar’;and

• USEPA Method 203 ‘Determination of the Opacity ofEmissions From Stationary Sources by ContinuousOpacity Monitoring Systems’.

4.1.2 Factors affecting method choiceUSEPA Method 9 involves the visual determination ofopacity using a qualified observer. To obtain certificationas an observer the candidate assigns opacity readings toa smoke generator plume. The observer must achieve seterror criteria, and be recertified every six months. It is,however, unlikely that sufficient visual observations willbe required to justify using this method.

USEPA Method 9A involves the remote measurementof plume opacity using a mobile lidar system and is notconsidered generally applicable in Australia due to thespecialised equipment requirements.

4.1.3 Recommended methodsThe technique recommended for visual observation ofopacity is British Standard BS 2742 ‘Use of theRingelmann and Miniature Smoke Charts’.

The technique recommended for continuous assessmentof opacity is USEPA Method 203 ‘Determination of theOpacity of Emissions From Stationary Sources byContinuous Opacity Monitoring Systems’.

4.1.4 Difficulties likely to be encounteredBS 2742 is relatively brief, and contains little guidancefor the observer. The major difficulty with using BS 2742is in obtaining an observer position that complies with thecriteria in the standard. Where this is impossible, the BritishStandard Miniature Smoke Chart can be used to obtainapproximate values (distance from observer to chart is onlyapproximately 1.5m). Factors that should be consideredwhen using Ringelmann charts are discussed below.• Store the chart carefully to prevent damage and soiling.

Store the chart away from sunlight. If the chart becomessoiled, or the paper discoloured, the results will be lessthan the actual value.

• Use an aluminium holder for the chart.• Typically the chart should be a distance of 15 m from

the observer, preferably with uniform illumination fromthe sky, with the sun at right angles to the line of vision.If the sun is behind or in front of the observer, incorrectresults will be obtained.

• The point of comparison with the chart is where theexhaust gases exit the stack. The angle of view fromthe horizontal should be as low as possible.

• The line of sight should not include more than oneplume, and for stacks of rectangular cross section,should be perpendicular to the longest side.

• The method is only applicable to sources containingblack, typically carbonaceous, particulate matter.Under no circumstances should the method be usedfor white or coloured particulate matter.

• The method will typically be used in situations wherethe obscuration of the plume is not constant, such assoot blowing or cyclical firing (regenerative furnaces).Under these circumstances, results must be recordedat regular intervals to establish the extent of the darksmoke emission (typically every 15 seconds).

• The record of observation should include the time,distances (observer/chart; chart/stack), wind direction,wind speed, sky condition, angle of the sun to the lineof sight and plume background). Photographs of thetest situation should be taken where possible.

4.2 Solid particulate matter4.2.1 Recommended methodThe technique recommended for analysis of emissionsis Australian Standard AS 4323.2 ‘Stationary SourceEmissions; Method 2: Determination of Total ParticulateMatter — Isokinetic Manual Sampling— Gravimetric Method’.

4.2.2 Difficulties likely to be encounteredAS 4323.2 allows for six different particulate mattersampling train configurations. In most circumstances,in-stack filtration is preferred for reasons of samplecollection efficiency and equipment requirements.Out-of-stack filtration requires a heated probe and heatedfilter box to prevent condensation occurring. The risk ofinefficient sample recovery from the nozzle, probe andfilter assembly is also increased. In-stack filtrationminimises the complexity of sample recovery. AS 4323.2Types A and C sampling trains are therefore preferred.If out of stack filtration is proposed, Types D and Fare preferred.

Although nozzles may be of plain bend or gooseneckdesign, for large diameter nozzles the plain bend designcan create difficulties in inserting the sampling apparatusthrough G4/100 sockets, as the extremity of the nozzleprotrudes beyond the filter or thimble holder assembly.

Glass fibre filters typically have a maximum operatingtemperature of 500oC; however, this should be confirmedwith the supplier. A number of glass fibre filter types aretreated with organic binders to improve the glass fibre matformation. Under no circumstances should these filters be


used. The maximum operating temperature of thefilter should not be considered in isolation. A practicalconsideration that is often neglected is the temperaturelimitations for the filter holder assembly components.Typically they contain Viton o-rings and PTFE thrustrings with maximum operating temperatures of 180oCand 200oC respectively.

For higher temperature applications, quartz fibre filtersand aluminosilicate (alundum) thimbles may be used.Alundum thimbles are often packed with refractory blanketto improve the collection efficiency of fine particulates.Thimbles, also available in glass fibre, are also usedwhere high particulate matter concentrations will besampled. If disc filters are used in these circumstances,the pressure drop quickly increases, preventing isokineticsampling rates from being maintained.

Filters or thimbles must be conditioned, preferably at50oC above the stack gas temperature, prior to the initialweighing to allow for potential weight loss under hightemperature exposure conditions.

Cellulose filters or thimbles should not be used forparticulate matter sampling. They are hygroscopic,making weight determinations extremely difficult. Hencethe method limit of detection is increased to allow for thevariability in weight change. They also have a high flowresistance and low maximum operating temperature(approximately 100oC).

As the preferred sampling train arrangement includes agas meter downstream of the vacuum pump, the pumpshould be leak free, preferably of the diaphragm type.Vane and piston pumps are not recommended due tothe high potential for leakage. Although not indicated inAS 4323.2, a pulsation dampener may be required inthe sample train between the pump and the flowmeasuring device.

The standard does not contain any acceptance/rejectioncriteria for isokineticity of the sample. The USEPA criteriaof 90 — 110% calculated sample isokineticity should beused as a guide to the validity of the sample.

The importance of leak checking the sampling train beforeand after a sample run cannot be overemphasised.Recording of leak check results should be routine.

4.3 Sulfuric acid mist/sulfur trioxide/sulfur dioxide

4.3.1 Recommended methodsThe technique recommended for batch analysis ofemissions is USEPA Method 8 ‘Determination of SulfuricAcid Mist and Sulfur Dioxide emissions From StationarySources’.

Techniques recommended for continuous analysis ofemissions are:• sampling in accordance with ISO Method ISO 10396

‘Stationary Source Emissions — Sampling for theAutomated Determination of Gas Concentrations’,followed by analysis in accordance with therecommended air quality method; or

• UV DOAS operated in accordance with TUV Rheinland,Germany, 17.BIm Sch V.

4.3.2 Difficulties likely to be encounteredUSEPA Method 8 raises the following issues to beconsidered when using the method.• The yellow to pink titrimetric endpoint using the thorin

indicator is extremely difficult to determine, even forexperienced analysts. An alternative analytical

procedure based on barium sulfate precipitateformation and gravimetric analysis should, therefore,be allowed.

• Under no circumstances should the nozzle and probebe constructed from any materials other thanborosilicate glass or quartz. The presence of metal ionsin solution appears to increase the difficulty in detectingthe end point.

• The presence of solid particulate salts containingsulfate in the exhaust gases is a positive interferencein the determination of sulfuric acid mist. Under thesecircumstances, the method should not be used,or alternatively the optional filter is used with thedetermination of sulfur trioxide and sulfur dioxideonly. It must be recognised that there are industrialprocesses where the determination of sulfuric acidmist is not possible.

• The isopropanol must be confirmed as peroxide free.• Although the method allows for an optional pre-test

sampling train leak check, this is not consideredadequate. Both the pre-test and post-test leakchecks should be carried out.

• Although the method allows for the determination ofexhaust gas moisture content by pre-test and post-testimpinger and silica gel gravimetric analysis, this is notconsidered adequate. Previous experience suggeststhat the loss of isopropanol during sampling introducessignificant errors into the moisture contentdetermination. A separate sampling train for exhaustgas moisture content determination is thereforenecessary.

• The contents of each impinger containing hydrogenperoxide solution should be analysed individually toallow the impinger train collection efficiency to bedetermined.

• The method calculations include a sample volumecorrection to a standard temperature of 293 K. Thisshould be amended to 273 K.

4.4 Total acid gases4.4.1 MethodsMethods available include:• New South Wales (NSW) Clean Air Regulations

Method No. 17(2)(o) ‘Determination of Acids and AcidGases’; and

• South Australian Office of the Environment ProtectionAuthority (SA EPA) Test Method 3.11 ‘Determinationof Total Acidity’.

4.4.2 Factors affecting method choiceOnly limited test method procedures are provided in NSWClean Air Regulations Method 17(2)(o). In addition, onlywater soluble acid gases are determined. It is therefore notconsidered to be a suitable method for determination oftotal acid gases.

4.4.3 Recommended methodThe technique recommended for analysis of emissions isSouth Australian Office of the Environment ProtectionAuthority Test Method 3.11 ‘Determination of Total Acidity’.

4.5 Nitric Acid4.5.1 MethodsMethods available include:• modified version of National Institute for Occupational

Safety & Health (NIOSH) Method 7903 ‘Inorganic Acids’Manual of Analytical Methods, 4th Edition;

• modified version of NSW Clean Air Regulations MethodNo. 17(2)(o) ‘Determination of Acids and Acid Gases’;and

• modified version of Environment Protection Authorityof Victoria (Vic EPA) Method B21.3 ‘Total Water SolubleFluoride’.


4.5.2 Factors affecting method choiceAs nitric acid mist would make NIOSH Method 7903unsuitable, and as its presence cannot easily be judged bysite-testing staff, this method is not considered appropriate.

Only limited test method procedures are provided in NSWClean Air Regulations Method 17(2)(o). A modified versionof this method is therefore not considered a suitableprocedure for the determination of nitric acid.

4.5.3 Recommended methodThe technique recommended for analysis of emissions isthe Vic EPA Method B21.3 ‘Total Water Soluble Fluoride’,modified as follows.• The impingement solution should be deionised water,

with subsequent analysis for nitrate by ionchromatography;

• A plug of glass wool should be included after the lastimpinger in the train to trap any entrained mist. The plugshould be combined with the last impinger contentsfor analysis.

• Note that particulate salts containing nitrate willinterfere.

4.6 Oxides of nitrogen (NO & NO 2)4.6.1 MethodsMethods available include:• USEPA Methods 7 — 7E ‘Determination of Nitrogen

Oxide Emissions From Stationary Sources’;• sampling in accordance with International Organization

for Standardisation (ISO) method ISO 10396 ‘StationarySource Emissions — Sampling for the AutomatedDetermination of Gas Concentrations’, followed byanalysis in accordance with the recommended airquality method; and

• open path spectrometry.

4.6.2 Factors affecting method choiceUSEPA Method 7 involves a short-term sample collectionprocedure (approximately 15 seconds) and has a restrictedmeasurement range (2–400 mg/Nm3 without sampledilution). The method is therefore considered unsuitablewhere nitrogen oxides concentrations vary with time,or high concentrations are present.

USEPA Method 7A has a higher upper limit (1250 mg/Nm3); however, the lower limit is also increased (125 mg/Nm3). The method limitation also remains regarding theshort sample period and is unsuitable if the nitrogen oxidesconcentration varies with time.

USEPA Method 7B has a working range of 57–1500 mg/Nm3, which would be acceptable in most instances, but theshort sample period is again of concern.

USEPA Method 7C has a working range of 13–1800 mg/Nm3, and sample collection period of approximately onehour. Therefore, it is suitable for determining averageemission rates.

USEPA Method 7D is very similar to Method 7C, and thechoice between them is considered to be a laboratorypreference. Both methods are acceptable manual samplingtechniques, with suitable averaging periods and detectionlimits.

4.6.3 Recommended methodsTechniques recommended for batch analysis of emissionsare:• USEPA Method 7C ‘Determination of Nitrogen

Oxide Emissions From Stationary Sources— Alkaline-permanganate/colorimetric method’; or

• USEPA Method 7D ‘Determination of Nitrogen OxideEmissions From Stationary Sources — Alkaline-permanganate/ion chromatographic method’.

Techniques recommended for continuous analysisof emissions are:• USEPA Method 7E ‘Determination of Nitrogen Oxide

Emissions From Stationary Sources (InstrumentalAnalyzer Procedure)’;

• sampling in accordance with ISO Method ISO 10396‘Stationary Source Emissions — Sampling for theAutomated Determination of Gas Concentrations’,followed by analysis in accordance with therecommended air quality method; or


4.6.4 Difficulties likely to be encounteredA number of items should be particularly noted with USEPAMethods 7C and 7D.• The impingers are not modified Greenburg-Smith

impingers, requiring fabrication in accordance with themethod dimensional criteria. This is a critical aspect ofthe method, ensuring increased contact time betweenthe sample gas and the absorbing solution.

• The sample flow rate must be in the range 400–500 mL/min. Flow rates in excess of 500 mL/min will result ininefficient collection of the nitrogen oxides.

• The contents of each impinger should be analysedindividually to allow the impinger train collectionefficiency to be determined.

• Ammonia is a positive interference. This is, however,not an issue with combustion gases, unless ammoniainjection is used for control of oxides of nitrogen.

4.7 Fluorine and chlorine compounds4.7.1 Recommended methodsThe technique recommended for batch analysis ofemissions is the Vic EPA Method B21.3 ‘Total WaterSoluble Fluoride’, modified as follows.• Allow for the analysis of chloride, in addition to fluoride,

by ion-selective electrode or ion chromatography.• Allow for in-stack or out-of-stack filtration to allow for

approximate segregation of particulate and gaseousfluorides, if required. If a mist is present in the exhaustgases (for example, wet scrubbing system exhaust) itshould be recognised that gaseous fluoride will beretained on the filter due to wetting of the filter. Underno circumstances should alundum thimbles be usedas the filtration media (the aluminosilicate ceramic willreact with the fluoride). The filter material and filterholder should preferably be constructed from PTFE.

• If out-of-stack filtration is selected, the filter and probemust be heated to prevent condensate forming onthe filter.

• The complete sampling train must be conditioned bypassing exhaust gases through the system for aminimum period of 30 minutes. The system is cleanedand the impinger catch discarded prior to commencingthe first sample.

• The contents of each impinger should be analysedindividually, to allow the impinger train collectionefficiency to be determined for both fluoride andchloride.

The technique recommended for continuous analysis isUV DOAS operated in accordance with TUV Rheinland,Germany, 17.BIm Sch V.

4.8 Carbon monoxide4.8.1 Recommended methodsThe techniques recommended are:• USEPA Method 10 ‘Determination of Carbon Monoxide

Emissions From Stationary Sources’;• USEPA Method 10A ‘Determination of Carbon

Monoxide Emissions in Certifying Continuous EmissionMonitoring Systems at Petroleum Refineries’;


• USEPA Method 10B ‘Determination of CarbonMonoxide Emissions From Stationary Sources’; or

• sampling in accordance with ISO Method ISO 10396‘Stationary Source Emissions — Sampling for theAutomated Determination of Gas Concentrations’,followed by analysis in accordance with therecommended air quality method; or


4.9 Hydrogen sulfide4.9.1 Recommended methodsTechniques recommended are:• USEPA Method 11 ‘Determination of Hydrogen Sulfide

Content of Fuel Gas Streams in Petroleum Refineries’;• Vic EPA Method B18 ‘Hydrogen Sulfide’, Standard

Analytical Procedures; or• USEPA Method 15 ‘Determination of Hydrogen Sulfide,

Carbonyl Sulfide and Carbon Disulfide Emissions FromStationary Sources’.

4.9.2 Difficulties likely to be encounteredVic EPA Method B18 specifies the use of arabinogalactanto inhibit the photo-decomposition of cadmium sulfide,which has problems of availability and cost.Arabinogalactan can probably be left out of the absorbingsolution provided appropriate precautions are taken toprevent photo-decomposition, such as:• wrapping the impinger train in aluminium foil or

containing the train in a light-proof container; and• keeping sample bottles wrapped in aluminium foil,

or other suitable light-proof material, prior tosample analysis.

USEPA Method 15 has a relatively short sample period.However, if a GC/FPD system is available on site,a number of grab samples can be analysed in a relativelyshort period. If this is not the case, the concern would bethe suitability of the method in determining the averageconcentration for a source that varies with time.

4.10 Heavy metals (excluding mercury)4.10.1 MethodsThe test method required must be appropriate for thedetermination of antimony, arsenic, cadmium, lead,vanadium, nickel and beryllium.

Methods available include:• NSW Clean Air Regulations Method 17(2)(k);• modified version of USEPA Method 108 ‘Determination

of Particulate and Gaseous Arsenic Emissions’; and• modified version of USEPA Method 12 ‘Determination

of Inorganic Lead Emissions From Stationary Sources’.

4.10.2 Factors affecting method choiceOnly limited test method procedures are provided in NSWClean Air Regulation Method 17(2)(k). It is therefore notconsidered satisfactory.

USEPA Method 12 collects the sample in a nitric acidsolution, whereas Method 108 uses deionised distilledwater. Due to the higher solubility of most metals in acidicsolutions, USEPA Method 12 is preferred to Method 108.

4.10.3 Recommended methodThe technique recommended for analysis of emissions isthe USEPA Method 12 ‘Determination of Inorganic LeadEmissions From Stationary Sources’ modified as follows.• In-stack or out-of-stack filtration should be allowed.• The contents of each impinger should be analysed

individually to allow the impinger train collectionefficiency to be determined for each metal.

• The probe nozzles should be constructed from glassor quartz only.

• Inductively coupled spectrophotometry (ICP) should beallowed as an alternative analytical procedure.

4.11 Mercury4.11.1 MethodsMethods available include:• USEPA Method 101 ‘Determination of Particulate and

Gaseous Mercury Emissions From Chlor-Alkali Plants— Air Streams’;

• USEPA Method 101A ‘Determination of Particulateand Gaseous Mercury Emissions From SewageSludge Incinerators’;

• NSW Clean Air Regulations Method; and• open path spectrometry.

4.11.2 Factors affecting method choiceThe NSW Clean Air Regulations Method provides onlylimited test method procedures. It is therefore notconsidered satisfactory.

4.11.3 Recommended methodsTechniques recommended for batch analysis ofemissions are:• USEPA Method 101 ‘Determination of Particulate and

Gaseous Mercury Emissions From Chlor-Alkali Plants— Air Streams’; or

• USEPA Method 101A ‘Determination of Particulateand Gaseous Mercury Emissions From Sewage SludgeIncinerators’.

The technique recommended for continuous analysis ofemissions is UV DOAS, operated in accordance withTUV Rheinland, Germany, 17.BIm Sch V.

4.12 Vinyl chloride monomer4.12.1 Recommended methodsTechniques recommended for analysis of emissions are:• USEPA Method 106 ‘Determination of Vinyl Chloride

From Stationary Sources’; or• National Institute for Occupational Safety & Health

(NIOSH) Method 1007 ‘Vinyl Chloride’, Manual ofAnalytical Methods, 4th Edition modified as follows:- Use a NATA-certified standard gas mixture forchromatography standards and for desorption studies.Desorption studies need only be conducted on oneoccasion for every different batch of activated charcoal.

It should be noted, however, that neither method isappropriate for the determination of vinyl chloride monomercontained in particulate matter.

4.12.2 Difficulties likely to be encounteredVinyl chloride is a known human carcinogen and shouldbe handled with appropriate caution.

NIOSH Method 1007 calibration procedure involves thedissolving of standard volumes of vinyl chloride gas incarbon disulfide. Carbon disulfide is volatile, toxic and anacute fire and explosion hazard, requiring all preparatorywork to be conducted in a fume cupboard.

NIOSH Method 1007, when used for source emissiontesting, can be affected by the adsorptive capacity ofactivated charcoal being reduced at high temperaturesand humidities. In the absence of adsorption dataconfirming otherwise, it is recommended that, at exhaustgas temperatures above 40oC, or relative humidities above60%, a glass or stainless steel condensate trap containedin an ice bath is used in the sample train upstream of theactivated charcoal tube. The sample probe should bemanufactured from stainless steel, Pyrex glass or PTFE


with a glass wool plug in the probe end for removal ofparticulate matter. All sample train connecting tubingshould be PTFE.

USEPA Method 106 involves less work than NIOSHMethod 1007; however, there are a number of significantdisadvantages. Samples must be analysed within 24 hours(aluminised Mylar) or 72 hours (Tedlar) in comparison withthe sample storage period of 10 days for activated charcoalsamples. Water vapour may also interfere with the vinylchloride peak, depending on chromatographic conditionsand column lengths, requiring a sample conditioning trapcontained in dry ice prior to the gas sampling loop.

4.13 Open path spectrometry4.13.1 MethodsMethods available include:• Fourier transform infra-red (FTIR) absorption

spectrometry; and• visible, ultraviolet (UV) and infra-red (IR) differential

optical absorption spectrometry (DOAS).

4.13.2 Factors affecting method choiceBoth UV DOAS and FTIR are relatively insensitive toparticulate matter.The major disadvantages of FTIR are:• water vapour and carbon dioxide interferences; and• the cryogenic system required for detector cooling.

The major advantages of UV DOAS are:• water vapour and carbon dioxide do not interfere;• lower detection limits; and• no cryogenic systems required.

4.13.3 Recommended methodsFTIR and DOAS are both acceptable provided they areoperated in accordance with performance-basedstandards. TUV, Rheinland, Germany, 17.BIm Sch Vcontains performance-based standards for using UV DOASsystems for a range of parameters.

4.13.4 Difficulties likely to be encounteredIn situ measurement can result in a number of unwantedeffects, which the operator must be aware of. The stackdiameter, which determines the optical path length,may be of such a size that the gas absorption deviatesfrom Beer-Lambert’s Law and becomes non-linear.Differential cross-sections also change with temperature.Therefore, calibrations must either be conducted at thesame temperature as the stack gases, or performed atambient temperatures with an appropriate temperaturecompensation function.

4.14 Recommended test methods— summary

Recommended source emission test methods for thespecific atmospheric contaminants described in Section 4are summarised in Table 2. Specific method modificationsdescribed in each section, however, must be implemented.

5 Other atmospheric contaminants5.1 General issuesMeasurement for the large majority of ambient air qualityand emission contaminants are covered in Sections 2 and4 above. For most purposes, these methods will coverroutine monitoring. From time to time, however, monitoringfor parameters not specified in this manual will be required.

This section sets out some general principles that willprovide guidance in sampling and analysis and assistin effective measurement of air quality.

The requirement for measurement must be assessed andthe purpose of monitoring must be determined. If ambientair quality monitoring is to assess population exposure toan air contaminant, then measurement needs to providesufficient data in terms of such factors as sensitivity andspecificity of analytical technique and comprehensivenessof sampling program. If monitoring is to assess emissionsfrom a plant, then it must be able to provide acomprehensive assessment of emissions underall conditions of plant operation.

Authoritative publications that should be examined forappropriate methods include:• Australian Standards;• International Organisation for Standardisation (ISO)

Standards;• USEPA Air Quality and Stationary Source Test Methods;• APCA/ACS/AIChE/APWA/ASCE/ASME/AOAC/HPS/ISA

Intersociety Committee on methods of air samplingand analysis;

• British Standards;• modified National Institute for Occupational Safety

and Health (NIOSH) Methods;• test methods published by other Australian States; and• American Society for Testing and Materials (ASTM)

Methods.

5.2 SamplingThe analysis of air quality can only be as good as thesample. It cannot be overemphasised that sampling iscritical in air quality monitoring. Sections 1 and 3 shouldbe consulted for general guidance.

The site chosen for ambient air quality measurement mustbe designed to meet the needs of the program in terms ofclassification of site, representativeness of populationexposure and maximum GLC (if required). In emissionstesting, it is the representativeness of the sample in termsof the process phase of interest and the homogeneity ofthe sample within that phase that is important.

The system used for sampling should be designed tominimise any change to the chemical or physical natureof the sample before analysis. The collection container,reaction cell or impinger where the sample is collected andpossibly reacted (for continuous samplers) and the samplecontainer (for batch samplers) must be constructed in sucha manner and with such materials that the sample collectedis not changed before analysis.

5.3 AnalysisThe method(s) for analysis should be selected fromauthoritative publications where the analysis has aproven track record when used for the applicationsunder consideration. The selection should be basedon application of the analysis for the task in the contextof air quality analysis. The procedure should be designedto take account of sampling procedures, conditions ofsampling, concentrations likely to be encountered,detection limits, interferences of unwanted compoundsand sampling matrix effects etc.

In the case of batch sampling, replicate aliquots shouldbe used for analysis. Where there are choices ofmeasurement techniques for the parameter in question,it would be appropriate to compare several methods interms of precision and accuracy. Where a large numberof analyses are required, it may be possible to use onemethod as the reference method and another, if it is muchsimpler, as the routine method.


Opacity 1. BS 2742; or

2. USEPA Method 203

Solid Particulate Matter AS 4323.2

Sulfuric Acid Mist/Sulfur 1. USEPA Method 8; orTrioxide/Sulfur Dioxide

2. sampling in accordance with ISO Method ISO 10396, followed by analysisin accordance with the recommended air quality method; or

3. UV DOAS operated in accordance with TUV Rheinland,Germany, 17.BIm Sch V

Total Acid Gases SA EPA Test Method 3.11

Nitric Acid Modified version of Vic EPA Method B21.3

Oxides of Nitrogen (NO & NO2) 1. USEPA Method 7C; or

2. USEPA Method 7D; or

3. USEPA Method 7E; or

4. sampling in accordance with ISO Method ISO 10396 followed by analysisin accordance with the recommended air quality method; or


Fluorine and Chlorine Compounds 1. Modified version of Vic EPA Method B21.3; or


Carbon Monoxide 1. USEPA Method 10; or

2. USEPA Method 10A; or

3. USEPA Method 10B; or

4. Sampling in accordance with ISO Method ISO 10396 followed by analysisin accordance with the recommended air quality method; or


Hydrogen Sulfide 1. USEPA Method 11; or

2. Vic EPA Method B18; or

3. USEPA Method 15

Heavy Metals (Excluding Mercury) Modified version of USEPA Method 12

Mercury 1. USEPA Method 101; or

2. USEPA Method 101A; or


Vinyl Chloride Monomer 1. USEPA Method 106; or

2. Modified version of NIOSH Method 1007

Table 2. Recommended emission test methods

ATMOSPHERIC CONTAMINANT RECOMMENDED TEST METHODS


The integrity of the analytical method must be tested bymeans of reagent blanks, field blanks, spiked samplesand reference materials. The recovery rate for the methodand use of internal standards is essential to determineits efficiency. Tests for likely interference by othercontaminants in the method selected must be determined.

Where new methodology is proposed, a number of stepsmust be followed prior to general introduction of the testmethod to the laboratory.

Methods must be documented in a standard format toensure that all details are included, and for ease of useby testing and laboratory staff.

Standard test method formats can be found in AustralianStandard AS 2929 ‘Test Methods — Guide to the Format,Style and Content’ or International Organization forStandardisation Method ISO 78-2 ‘Chemistry — Layout forStandards Part 2: Methods of Chemical Analysis’.Alternatively the standard format contained in USEPAStationary Source Test Methods can be followed.

The documentation must include the proposed methodscope, the method range and a summary of validation datafor the new method. The term ‘new method’ applies to anynew method introduced to the laboratory. This includes thedevelopment of a completely new test method, modificationof an existing standard test method or simply the adoptionof a standard test method.

NATA describes an appropriate list of procedures andparameters required for validating test methods inTechnical Note 17 ‘Requirements for the format andcontent of test methods and recommended proceduresfor the validation of chemical test methods’ (1997).

5.4 Method choiceThe method chosen for analysis should be based on theabove criteria. Additional factors that should be consideredin such a choice are the priority of the program, the extentof monitoring, the time period of the program, the likelihoodof a repeat program or a continuation of the program.

6 Biological monitoring6.1 IntroductionSampling and analysis of biological materials raisesissues not normally encountered when sampling inorganicmaterials. Biological samples exhibit substantial variabilitywithin the sample, between duplicate samples andbetween samples taken at different times and places.These variations are both environmental and geneticand must be allowed for in sampling methods.

In biological monitoring, sampling is a large potentialsource of variability and error. Some general rulessuggest minimum distances from the road such as100 m for vegetation, and much greater for animals(depending on their feeding patterns).

The random sampling of a large number of individualsamples, collected in line with certain guidelines, andpooling of collected matter before analysis is normallyrecommended. In the case of leaves or small organisms,several hundred samples may be collected, driedand homogenised to form a composite sample.When considering larger animals, smaller numbersare of course necessary and greater variability is tobe expected.

Techniques include the following:• A large number of samples in a single area and pool.• Selective sampling. For vegetation — new leaves or

leaves at a certain height above ground or with aparticular orientation to the potential polluting source.For animals — select certain characteristic such as sex,age, species. This sampling may reduce variability butthe sample may be biased.

• Random sampling, which will result in wide variabilityin results.

6.2 Fluoride6.2.1 Sample preparationFluoride is widespread in the environment and isfound at various concentrations in almost all natural andmanufactured materials. Sample preparation and analysisprocedures must be mindful of this fact.

The sample is reduced in bulk to permit efficient mixing byhand sheers or, if dry, by a cutting mill. After mixing, a smallportion, say 10–20 g, is taken for moisture determinationby heating at 80oC for 24 hours.

Around 50–100 g of material is taken for the analysis andis wet with alkaline fluoride-free calcium oxide slurry, thendried, ashed and fused. The fused material is thenavailable for further analysis.

6.2.2 Analytical methodsMethods 203–205 in Methods of Air Sampling andAnalysis, 3rd Edition of Intersociety Committee AWMA, ACS,AIChE, APWA, ASME, AOAC, HPS, ISA 1988. Ed. James PLodge Jr., describes several types of methods the could beused.

The recommended types of methods for routine fluoridein vegetation monitoring are:• potentiometric; or• semi-automated with potentiometric or

spectrophotometric analysis.

air quality sampling manual

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