Environmental Laboratory Accreditation Course for Radiochemistry
Presented byMinnesota Department of HealthPennsylvania Department of Environmental ProtectionU.S. Environmental Protection AgencyWisconsin State Laboratory of Hygiene
About this course
This radiochemistry course was coordinated by Susan Wyatt of the MN Dept of Health Environmental Laboratory Certification program in 2006 -2007 to fill an existing gap in the USEPA certification officer’s training course.
The course was presented in three locations nationwide beginning in Minnesota in September 2006; then Pennsylvania in December 2006; and finally, Arizona in February 2007.
The instructors
Jeff Brenner, MN Dept of Health
Michella Karapondo, USEPA
John Lorenz, MN Dept of Health
Richard Sheibley, PA Dept of Env Protection
Lynn West, WI State Lab of Hygiene
Susan Wyatt, MN Dept of Health
Course Organization
Pre Test: basic knowledge 3 ½ days instruction
USEPA requirements Radiation theory & safety Radiochemistry instrumentation, &
methods PT samples
Data review
Course Objectives
Gain knowledge sufficient to assess laboratories NELAC compliance USEPA SDWA compliance
Nurture awareness of newer radiochemistry technologies and methods
Recent Legislation
Michella Karapondo
U.S. Environmental Protection Agency
Drinking Water Program Update
December 2006OGWDW, TSC
Office of Ground Water and Drinking Water
Develop drinking water regulations Set drinking water standards Proficiency testing criteria Approve drinking water methods
Evaluate and develop analytical methods Alternate testing procedures (ATPs)
Implement laboratory certification program Radiochemistry audits NELAC
What do we do?
National Environmental Laboratory Accreditation Conference (NELAC)
OGWDW endorsement of NELAC 2002 letter from OGWDW supports use of
NELAC standard Drinking water accreditation must
be as stringent as USEPA’s certification Certification by method AND analyte vs.
technology/analyte or analyte group Drinking water requires use of defined
methods Performance based methods are NOT ALLOWED! New methods allow for some laboratory flexibility
Proficiency Testing (PT) Program for Drinking Water
EPA -setstandardsUSEPA Criteria Document
NIST/NVLAP
A2LA Accredits providers
PT Providers
Conducts PT StudiesLaboratoriesAnalyze PT Samples
CO/AA - Reviews PT Results
Note that EPA terminology is different – Performance Evaluation – PE Study
Where can I find PT criteria?
Regulatory acceptance limits are in the CFR Called “Performance Evaluation” in the CFR
Inorganic criteria: 40 CFR 141.23(k)(3)(ii) VOC criteria: 40 CFR 141.24(f)(17)(i) and (ii) for
vinyl chloride SOC criteria: 40 CFR 141.24(f)(19)(i)(B) Lead/copper criteria: 40 CFR 141.89(a)(1)(ii)(A)
and (B) DBP criteria: 40 CFR 141.131(b)(2) – NOTE that
the 2005 CFR does not have the updated DBP criteria!
NELAC FoPT Tables http://www.epa.gov/nelac/pttables.html
Radiochemistry Audits for EPA Region, State and Tribal Laboratories
TSC currently supports through extramural monies
State laboratories needing certification are currently audited using a contractor May not be an option in the near future
We are working with the regions to find alternate funding
Drinking Water Methods
Developed by TSC and ORD Other government agencies
USGS Review methods from voluntary consensus
method standard bodies ASTM, Standard Methods, AOAC
Approved through the regulatory process
Evaluating Methods: The Alternate Testing Program
40 CFR 141.27 allows “alternate analytical techniques”
MUST have written permission from EPA A letter from EPA OR Publication in the Federal Register
ATPs are national – there are no lab specific ATPs for drinking water
For drinking water protocol, call Sample Control Center at 703-461-2100
Questions? Contact [email protected]
Alternate Testing Program (ATP)
M e tho d sub m itte d to EPA
Is the m e tho de q u iva le n t toa n a p p ro ve dDW m e tho d ?
Le tte r issue d sta ting m e tho dm a y b e use d
M e tho d is p ro p o se d in Fe d e ra lRe g iste r
Eva lua te d b y Te c hn ic a l Sta ff
Ye s No
Is the m e tho dsu ita b le fo r
DrinkingWa te r?
No
Ye s
Le tte r se n t to sub m itte rre je c ting m e tho d
ATP letters will be posted on OGWDW’s web site
Where can I find approved methods?
Approved methods are listed in CFR Inorganic methods: 40 CFR 141.23 Organic methods: 40 CFR 141.24 Methods for radioactivity: 40 CFR 141.25 Lead and copper: 40 CFR 141.89 Disinfection by-products: 40 CFR 141.131
BUT, the CFR is published only once a year! Keep an eye on the Federal Register!
Approved methods are listed on OGWDW’s web site http://www.epa.gov/safewater/methods/methods.html Some EPA methods are available in PDF format
National Environmental Monitoring Index (NEMI)
National Environmental Monitoring Index (NEMI)
Database of methods applicable for monitoring water for chemical and microbiological pollutants http://www.nemi.gov/
Useful for comparing/contrasting methods Caution! NEMI may not always contain
correct/approved version of method Can search by analyte, matrix, CAS number,
and/or regulatory requirement Public release October 2002 – announced by
joint USGS/USEPA letter
NEMI Search – General
NEMI Search – By Regulation
Safe Drinking Water Act (SDWA)
Authorizes EPA to set enforceable health standards for contaminants in drinking water affects all public water systems serving at
least 25 people or having at least 15 service connections
required that the National Primary Drinking Water Regulations be drafted
amended in 1977, 1979, 1980, 1986, and 1996 (reauthorized and amended).
How does OGWDW decide what to regulate?
1996 SDWA amendments changed the process
Contaminant Candidate List (CCL)
Unregulated Contaminant Monitoring (UCMR)
Regulatory Determination
Regulatory Promulgation
Regulatory Implementation
Six Year Review
Regulations
Proposal
Public Comment
Final Rule
Federal Register Published daily by the Office of Federal
Register (National Archives and Records Administration – NARA)
Notices, Proposed & Final Rules Preamble
An explanation of rule Contact person Docket information How to submit comments (for proposed rules)
Rule The legal requirements Only lists changes
Available on line at http://www.gpoaccess.gov/fr/index.html
FR Citation (69 FR 18166 April 6, 2004)Preamble to Proposed Methods Update Rule
Language in Proposed Methods Update RuleFR Citation (69 FR 18166 April 6, 2004)
* * * Indicates no change in current rule language
Dockets
Proposed rule dockets contain supporting documents & public comments
Final rule docket also has Agency response to public comments
Docket number is listed in preamble Electronic access to dockets at:
http://www.regulations.gov
Want to know when something is published?
Subscribe to EPA’s ListServer to receive an email when a FR is published relating to “water”
https://lists.epa.gov/read/all_forums/
Code of Federal Regulations (CFR)
Codification of Federal Rules Rule language (no preamble)
50 titles - Drinking Water is Title 40 Published volumes are updated annually
Title 40 is updated on July 1 Incorporates all changes from previous year Available on line at
http://www.gpoaccess.gov/cfr/index.html e-CFR updated frequently (not official
version)
Radionuclides in Drinking Water
1976 - First radionuclide regulations promulgated
1986 - Amendments to SDWA 1991 – Proposed regulations and revisions 1996 – Amendments to SDWA 2000 – Final radionuclide rule
Analytical Methods for Radionuclides62 FR 10168 – March 5, 1997
Approved the use of 66 radionuclide methods 54 methods proposed in the 1991 radionuclide
proposed rule 12 methods from public comments to that
proposal Full list of approved radionuclide methods
in 40 CFR 141.25
Radon64 FR 59246 - November 2, 1999 – Proposed Rule
Will apply to community water systems using ground water or mixed ground and surface water
Multi-Media Mitigation program plans to address indoor air along with water
Rn-222 MCL = 300pCi/L or AMCL = 4,000pCi/L
first application of AMCL and MMM
Final rule 2007 or 2008 (or longer!)
Radionuclide Rule65 FR 76708 - December 7, 2000 - Final Rule
Retains previously regulated radionuclide contaminants and adds requirements for Uranium
Applies to community water systems Initial monitoring complete by December 31,
2007 Sets a new MCL for Uranium – 30 ug/L Retains the existing MCLs for:
Radium-226/228 – 5 pCi/L Gross alpha particle radioactivity – 15 pCi/L
Includes Ra-226, but excludes radon and uranium Beta particle and photon activity – 4 mrem/yr
Set all Maximum Contaminant Level Goals (MCLGs) for radionuclides at 0 pCi/L
Analytical Method for Uranium69 FR 52176 - August 25, 2004
Approves three ICP-MS methods for Uranium EPA 200.8, revision 5.4 SM 3125 (20th edition) ASTM D 5673-03
Method Update Rule69 FR 18166 – April 6, 2004 – Proposed Rule
OGWDW and OST Updated versions of ASTM & SM methods
Too many to list here ATP methods Micro ATP Protocol EPA 327 – Chlorine dioxide Proposed withdrawal of Atrazine immunoassay Georgia Tech method for the
determination of Ra-226 and Ra-228 by Gamma-ray Spectrometry
Final rule – 2006
Footnote 14: "The Determination of Radium-226 and Radium-228 in Drinking Water by Gamma-ray Spectrometry Using HPGE or Ge(Li) Detectors," Revision 1.2, December 2004. Available from the Environmental Resources Center, Georgia Institute of Technology, 620 Cherry Street, Atlanta, GA 30332-0335, USA, Telephone: 404-894-3776. This method may be used to analyze for radium-226 and radium-228 in samples collected after January 1, 2005 to satisfy the radium-226 and radium-228 monitoring requirements specified at 40 CFR 141.26.
Resources OGWDW Website
http://www.epa.gov/safewater
Drinking Water Regulations http://www.epa.gov/safewater/regs.html
Laboratory Certification http://www.epa.gov/safewater/labcert Lab Cert Manual as PDF
http://www.epa.gov/safewater/labcert/labindex.html
Federal Register http://www.gpoaccess.gov/fr/index.html
Resources
PT Tables http://www.epa.gov/nelac/pttables.html
Drinking Water Methods http://www.epa.gov/safewater/methods/methods.html
NEMI http://www.nemi.gov/
Radionuclide page http://www.epa.gov/safewater/radionuc.html
39
Implementation: USEPA Drinking Water Certification Program
Michella Karapondo
U.S. Environmental Protection Agency
Topics
Authority for certification program Program structure and responsibilities Certification process and criteria
Safe Drinking Water Act (SDWA)
Authorizes EPA to set enforceable health standards for contaminants in drinking water affects all public water systems serving at least 25
people or having at least 15 service connections required that the National Primary Drinking Water
Regulations be drafted amended in 1977, 1979, 1980, 1986, and 1996
(reauthorized and amended).
Required By 40 CFR 141.28
“… Samples may be considered only if they have been analyzed by a laboratory certified by the state except that measurements for alkalinity, calcium, conductivity, disinfectant residual, orthophosphate, pH, silica, temperature, and turbidity, may be performed by any person acceptable to the state.”
Primary Enforcement Responsibility 40 CFR 142.10
A State has primacy when…
it has adopted drinking water regulations no less stringent than the Federal regulations
it has adopted and implemented adequate procedures for enforcement of State regulations
inventory of systems sanitary surveys establishes and maintains a certification
program and designates a CPM certified by the Administrator responsible for the State certification program
USEPA Drinking Water Laboratory Certification Program
Program began in 1978 Hierarchical structure Fundamentals are in the “Lab Cert
Manual” Accept NELAP accreditation
Certification Program Structure
USEPAOffice of Ground Water and Drinking Water
Regional Laboratory/Certification Program
State Laboratory & Certification Program
Private Laboratories
Certification Officers
Should have a college degree in the discipline for which they certify and have recent laboratory experience
Should have experience in lab evaluation and quality assurance
Successfully complete EPA's Certification Officers training course
Scope of Certification
Certification is granted in three areas:
Chemistry Microbiology Radiochemistry
Certification Process
Lab requests(re)certification
Lab passesPT sample
Set date for on-site
audit
On-site auditperformed
Lab certified for3 years
On-site Evaluation Items
Are promulgated/approved methods being used and requirements of those methods met
Are appropriate quality systems in place Are personnel qualified and sufficient Are laboratory facilities, equipment and
supplies adequate Data audit
Types of Certification
Certified Provisionally certified Not certified
Interim certification
Certified
Laboratory meets the regulatory performance criteria by: using promulgated/approved methods demonstrating successful performance on
proficiency testing (PT) samples by analyte and method on an annual basis
passing an on-site audit at least every 3 years Must notify Certification Authority of any
major changes (personnel, equipment, facility)
Provisional Certification
Laboratory has minor deficiencies but is still able to consistently produce valid data using promulgated/approved methods
insufficient/incomplete documentation failed PT samples
Provisional Status
Must notify clients of status For a limited time -- follow up is
needed to ensure corrective actions have been completed or lab should be decertified
May continue to analyze compliance samples; however:
Not Certified
Laboratory possesses deficiencies and cannot consistently produce valid data has a lack of equipment/personnel makes changes in method(s) that are not
allowed is unresponsive to deficiencies found resulting in
provisional certification
Interim Certification
Impossible or unnecessary to perform an on-site audit for new contaminants when no PT sample is available when constraints prevent a timely on-site
audit Lasts until next scheduled on-site or a PT
sample is available
More Drinking Water Lab Cert Information
OGWDW Web site http://www.epa.gov/OGWDW/
TSC Lab Cert Team E-mail addresses: [email protected] [email protected] (micro) [email protected] [email protected]
Web Sites
Laboratory Certification Manual, 5th Edition:http://www.epa.gov/safewater/labcert/index.html
Methods (listed by contaminant/method number):http://www.epa.gov/safewater/methods/methods.html
CFR: http://www.gpoaccess.gov/cfr/index.html
DW REGS: http://www.epa.gov/safewater/regs.html
List of state certified labs: http://www.epa.gov/safewater/labs/index/html
Proficiency Testing Samples:http://www.epa.gov/nelac/pttables.html
Proficiency Testing
Richard Sheibley
Pennsylvania Dept of Env Protection
Proficiency Testing Requirements
Gross alpha Gross beta Tritium Radium 226 Radium 228 U (natural)
Strontium 89 Strontium 90 Gamma
Barium 133 Cesium 134 Cesium 137 Cobalt 60 Zinc 65
Iodine 131
At least one successful PT study per year (two PTs per year for NELAC compliance) for the following:
ERA WS RadCheMTM PT Study Activity Ranges *
Activity Range Units Activity Range Units
Strontium-89/90 Iodine-131
Strontium-89 10 - 70 pCi/L Iodine-131 1 - 30 pCi/L
Strontium-90 2 - 45 pCi/L
Gamma Emitters NaturalS
Barium-133 9 - 110 pCi/L Radium-226 1 - 20 pCi/L
Cesium-134 10 - 96 pCi/L Radium-228 1 - 20 pCi/L
Cesium-137 20 - 240 pCi/L U-Nat 2 - 70 pCi/L
Cobalt-60 10 - 120 pCi/L U-Nat (mass) 3 - 104 ug/L
Zinc-65 30 - 360 pCi/L
GroSS Alpha/Beta TritiuM
Gross Alpha (Th-230) 3 - 75 pCi/L Tritium 1000 - 32000 pCi/L
Gross Beta (Cs-137) 4 - 65 pCi/L
* As defined by NELAC criteria adopted from National Standards for Water Proficiency Testing Studies Criteria Document , EPA NERL-Ci-004, 12/30/98
PT Study Activity Ranges
ERA WS RadCheMTM PT Study Acceptance Criteria *
Acceptance Limits (pCi/L) Acceptance Limits (pCi/L)
Strontium-89/90 Iodine-131
Strontium-89 10 - 70 8.66 Iodine-131 1 - 30 3.46
Strontium-90 2 - 45 8.66 > 15 - 30 5.20
Gamma Emitters NaturalS
Barium-133 9 - 50 8.66 Radium-226 1 - 20 0.260(AV)
> 50 - 110 0.173(AV) Radium-228 1 - 20 0.433(AV)
Cesium-134 10 - 96 8.66 U-Nat 2 - 35 5.20
Cesium-137 20 - 100 8.66 > 35 - 70 0.173(AV)
> 100 - 240 0.0866(AV) U-Nat (mass) (ug) 3 - 52.2 7.76
Cobalt-60 10 - 100 8.66 > 52.2 - 104 0.173(AV)
> 100 - 120 0.0866(AV)
Zinc-65 30 - 50 8.66
> 50 - 360 0.173(AV)
GroSS Alpha/Beta TritiuM
Gross Alpha (Th-230) 3 - 20 8.66 Tritium 1000 - 4000 294(AV 0.0933 )
> 20 - 75 0.433(AV) > 4000 - 32000 0.173(AV)
Gross Beta (Cs-137) 4 - 50 8.66
> 50 - 65 17.3
AV = Assigned Value
* As defined by NELAC criteria adopted from National Standards for Water Proficiency Testing Studies Criteria Document , EPA NERL-Ci-004, 12/30/98
PT Study Acceptance Criteria
ERA WS RadCheMTM PT Study General Information
Every PT standard offered quarterly
WS Radiochemistry studies are open for 45 days
All analytes must be reported in triplicate for each method to be evaluated
PT results may be submitted online, by fax or mailed
Particpants can select a copy of their evaluation report sent to any accrediting authority
ERA will evaluate a laboratory's results after study completion. However, each data point will be flagged as received after study results were posted.
Please feel free to contact ERA with questions or concerns:
Sherrod KyleManager, RadiochemistryEnvironmental Resource AssociatesP: 800-372-0122F: [email protected]
PT Vendor information
ERA WS RadCheMTM PT Study Common Issues
Method 903.0 and similar coprecipitation methods- Method measures all alpha emitting Radium isotopes and is not specific to Ra-226
- For samples and PT standards that contain Ra-228, its decay product Ra-224 is separated also
- Ra-224 and its alpha emitting progeny (Rn-220, Po-216 and Po-212) will bias Ra-226 results high
- This issue is magnified when Ra-228 is set high and Ra-226 is set low in their activity range
- Solution: Allow Ra-224 (3.66 d halflife) and progeny isotopes to decay prior to counting for Ra-226
Gross Beta vs. Cs-137- When Cs-137 is used as a calibration isotope for gross beta analysis, conversion and auger electrons
from Ba-137 should be accounted for when assigning gross beta activity values
- This results in an additional 9.34% gross beta activity vs. Cs-137 activity
- Failure to account for the added gross beta activity can result in a high bias in reported results
Reporting Problems- Reporting laboratory results is considered part of the PT evaluation. Below are common problems:
- incorrect units
- results not in triplicate
- incorrect decay correction
- unaccounted dilution factors
Most common lab deficiencies for Rad PTs
Other ERA RadCheMTM PT Studies
The MRaDTM Multi-Media Radiochemistry PT program offers the following additional matrices
and an expanded isotope list for laboratories to demonstrate capabilities semiannually:
Soil Radionuclides Air Filter Radionuclides Air Filter Gross Alpha/Beta
Actinium-228 Plutonium-238 Americium-241 Uranium-234 Gross Alpha (Th-230)
Americium-241 Plutonium-239 Cesium-134 Uranium-238 Gross Beta (Cs-137)
Bismuth-212 Strontium-90 Cesium-137 Uranium-Total
Bismuth-214 Thorium-234 Colbalt-60 Uranium-Total (mass)
Cesium-137 Uranium-234 Manganese-54
Lead-212 Uranium-238 Plutonium-238
Lead-214 Uranium-Total Plutonium-239
Potassium-40 Uranium-Total (mass) Strontium-90
Vegetation Radionuclides Water Radionuclides Water Gross Alpha/Beta
Americium-241 Strontium-90 Americium-241 Uranium-234 Gross Alpha (Th-230)
Cesium-137 Uranium-234 Cesium-134 Uranium-238 Gross Beta (Cs-137)
Colbalt-60 Uranium-238 Cesium-137 Uranium-Total
Curium-244 Uranium-Total Colbalt-60 Uranium-Total (mass) Water Tritium
Potassium-40 Uranium-Total (mass) Plutonium-238 Tritium
Plutonium-238 Plutonium-239
Plutonium-239 Strontium-90
We also provide radiochemistry LCS/MS standards for use as laboratory batch QC for any
of our PT isotopes
PTs in other matrices/quality control stds
Radiochemistry Theory
John Lorenz
Minnesota Department of HealthPublic Health Laboratory
What we’ll cover
What radiation is Types of radiation What radioactive material is Characteristics of radioactive
material and radiation How these characteristics affect
analytical methods MCLs and analysis (counting)
BasicsBasicsOfOf
RadiationRadiation
RADIATION IS ENERGY TRAVELING THROUGH SPACE IN THE FORM OF WAVES OR PARTICLES
RADIATION IS ENERGY TRAVELING THROUGH SPACE IN THE FORM OF WAVES OR PARTICLES
LIGHTLIGHT
MICROWAVESMICROWAVES
HEATHEAT
NUCLEAR RADIATIONNUCLEAR RADIATION
IONIZING vs. NON-IONIZINGIONIZING vs. NON-IONIZING
LIGHTLIGHT
MICRO- WAVESMICRO- WAVES
HEATHEAT
NUCLEAR RADIATIONNUCLEAR RADIATION
}
}
NON-NON-IONIZINGIONIZING
IONIZING IONIZING +
-
HEATING
IONIZATION
Ionization causes health risksIonization causes health risks
Ionization allows detectionIonization allows detection
Ionization
RadioactiveRadioactive
MaterialMaterial
Radioactive Material - Atoms
Nucleus with protons and neutrons Orbiting Electrons
Radioactive Material – Unstable Nuclei
Improper balance of protons and neutrons in nucleus
Excess energy
Radioactive Material – Unstable Nuclei
Reaches balance by giving off particles or energy waves or both
Radioactive Material Radiation The change of nuclear structure is called
nuclear disintegration
Radioactive material
Atoms emitting radiation are radioactive material
A specific type of radioactive material is called a radionuclide
Radioactive material
Atoms emitting radiation are radioactive material
A specific type of radioactive material is called a radionuclide
Radium-226 Radium-228 Uranium-238 Strontium-90 Hydrogen-3
Isotopesof Radium
Radioactive material
Radionuclides can be represented in alternative ways
226Ra = 226Ra = Ra-226
228Ra = 228Ra = Ra-228
239U = 239U = U-238
90Sr = 90Sr = Sr-90
3H = 3H = H-3(Tritium)Tritium)
88
88
92
38
1
Uranium Decay Series
U-2384.5E9 y
Ra-2261600 y
Rn-2223.8 d
Po-2183.1 min
Pb-21426.8 min
Bi-21419.9 min
Po-214160 usec
Pb-21022.3 y
Bi-2105 d
Po-210138 d
Pb-206Stable
Th-23424 d
Pa-234m1.2 m
U-234240,000 y
Th-23077,000 y
Thorium Decay Series
Ra-2285.8 yr
Ac-2286.1 hr Th-228
1.9 yr
Ra-2243.7 day
Rn-22056 sec
Po-2160.15 secPb-212
11 hr
Bi-21261 min
Po-212310 nsec
Pb-208Stable
Th-2321.4E10 yr
Tl-2083.1 min
Types of Radiation
Alpha ()
Beta ()
Gamma ()
ALPHA DECAYALPHA DECAY
NUCLEUSNUCLEUS++
PARTICLE FORM OF RADIATION PARTICLE FORM OF RADIATION
LOW PENETRATING ABILITY LOW PENETRATING ABILITY
SIGNIFICANT INTERNAL EXPOSURE HAZARD SIGNIFICANT INTERNAL EXPOSURE HAZARD
BETA DECAYBETA DECAY
PARTICLE FORM OF RADIATION PARTICLE FORM OF RADIATION
MODERATE PENETRATING ABILITY MODERATE PENETRATING ABILITY
PREDOMINANTLY INTERNAL EXPOSURE HAZARD PREDOMINANTLY INTERNAL EXPOSURE HAZARD
NUCLEUSNUCLEUS- -
GAMMA DECAYGAMMA DECAY
WAVE FORM OF RADIATION WAVE FORM OF RADIATION
SIGNIFICANT PENETRATING ABILITY SIGNIFICANT PENETRATING ABILITY
EXTERNAL & INTERNAL EXPOSURE HAZARD EXTERNAL & INTERNAL EXPOSURE HAZARD
NUCLEUSNUCLEUS
Characteristics of Radioactive Material
Activity Half-life (T1/2) Random decay Geometry Ingrowth
Activity - quantitative
Number of nuclear disintegrations per unit time Disintegrations per second (dps) Disintegrations per minute (dpm)
May be more or less than one radiation emission per disintegration
Not dependent on temperature or pressure
Activity Units Curie (Ci)
37 billion (3.7x1010) disintegrations per second
Millicurie (mCi = 10-3 Ci)Microcurie (Ci = 10-6 Ci)Nanocurie (nCi = 10-9 Ci)Picocurie (pCi = 10-12 Ci)
1 pCi = 2.22 dpmFemtocurie (fCi = 10-15 Ci)
Activity Units
Becquerels (Bq)1 disintegration per second (dps)Megabecquerels
1 Bq = 27 pCi
Activity - quantitative
Proportional to number of atoms of radionuclide
Atoms
Atoms
Atoms
Activity
Activity
Activity
Activity - quantitative
Proportional to number of atoms of radionuclide
For Ra-226
1 g
2 g
4 g
1Ci
2 Ci
4 Ci
Activity - quantitative
Inversely proportional to half-lifeInversely proportional to half-life
T1/2
T1/2
T1/2Activity
Activity
Activity
Half-life (T1/2)
The time it takes for half of the radioactive material to decay, or
The time it takes for decay to reduce the amount of radioactive material by 50%.
Half-life
Iodine – 131: Half-life = 8 days
TodayActivity = 200 pCi
After 8 DaysActivity = 100 pCi
After 16 DaysActivity = 50 pCi
Activity - quantitative
Inversely proportional to half-lifeInversely proportional to half-life
T1/2
T1/2
T1/2Activity
Activity
Activity
Activity - quantitative
Inversely proportional to half-lifeInversely proportional to half-life
For 2.7x10For 2.7x102121 atoms atoms
30 y
1600 y
4.5 billion y .00000035 Ci
1 Ci
53 CiCs-137
Ra-226
U-238
Half-life (T1/2)
T1/2 for commonly used radionuclides U-238U-238 4.5 billion years Cs-137 30.1 years Co-60 5.3 years P-32 14.3 days I-131 8.0 days Rn-222 3.8 days Ac-228 6.3 hours F-18 1.8 hours
Half-life - Implications
Decay correction: Accounts for difference from collection until analysis
Prompt analysis needed for short half-life nuclides like Actinium-228
(T1/2 = 6.1 hr, surrogate for Ra-228)
Decay constant () relates activity to half-life = ln2/T1/2
A = N
Radioactive Decay is Random
Variable decay rate Source of uncertainty in analysis
Reduced by longer timeReduced by higher activity
Decay Rate(dpm)
20 -
15 -
10 -
5 -
0 -
1:00 2:00 3:00
GeometryGeometryRefers to the shape and position of the sourceRefers to the shape and position of the source
Must be consistent for calibration and Must be consistent for calibration and analysisanalysis
Ingrowth One radionuclide decays to another
radionuclide If decay product has much shorter
half-life, its activity will equal parent’s activity
0
100000
200000
300000
400000
500000
600000
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Uranium Decay Series
U-2384.5E9 y
Ra-2261600 y
Rn-2223.8 d
Po-2183.1 min
Pb-21426.8 min
Bi-21419.9 min
Po-214160 usec
Pb-21022.3 y
Bi-2105 d
Po-210138 d
Pb-206Stable
Th-23424 d
Pa-234m1.2 m
U-234240,000 y
Th-23077,000 y
Thorium Decay Series
Ra-2285.8 yr
Ac-2286.1 hr Th-228
1.9 yr
Ra-2243.7 day
Rn-22056 sec
Po-2160.15 secPb-212
11 hr
Bi-21261 min
Po-212310 nsec
Pb-208Stable
Th-2321.4E10 yr
Tl-2083.1 min
Short half-life decay product as surrogate for longer lived parent (Ra-228 Ac-228)
After chemical processing, allowing ingrowth of shorter lived nuclides
Ingrowth - Implications
CharacteristicsCharacteristics
OfOf
RadiationRadiation
Characteristics of Radiation
Physical form (Particle or wave) Energy (keV or MeV) Charge Mass Penetration
Range Attenuation
Interactions with matter Velocity
ALPHA DECAYALPHA DECAY
NUCLEUSNUCLEUS++
PARTICLE FORM OF RADIATION PARTICLE FORM OF RADIATION
LOW PENETRATING ABILITY LOW PENETRATING ABILITY
SIGNIFICANT INTERNAL EXPOSURE HAZARD SIGNIFICANT INTERNAL EXPOSURE HAZARD
BETA DECAYBETA DECAY
PARTICLE FORM OF RADIATION PARTICLE FORM OF RADIATION
MODERATE PENETRATING ABILITY MODERATE PENETRATING ABILITY
PREDOMINANTLY INTERNAL EXPOSURE HAZARD PREDOMINANTLY INTERNAL EXPOSURE HAZARD
NUCLEUSNUCLEUS- -
GAMMA DECAYGAMMA DECAY
WAVE FORM OF RADIATION WAVE FORM OF RADIATION
SIGNIFICANT PENETRATING ABILITY SIGNIFICANT PENETRATING ABILITY
EXTERNAL & INTERNAL EXPOSURE HAZARD EXTERNAL & INTERNAL EXPOSURE HAZARD
NUCLEUSNUCLEUS
Other Origins for RadiationOther Origins for Radiation
Electron CaptureElectron Capture
Internal ConversionInternal Conversion
BremsstrahlungBremsstrahlung
Radiation Penetration
alphaalpha
betabeta
gammagamma
PaperPaper PlasticPlastic LeadLead
Penetration - Implications
and intimate contact with detection medium
emitters can pass through containers and detector housings
Self-absorption can occur in material containing radionuclides
Self AbsorptionSelf Absorption
1 mg. solids1 mg. solids9 dpm9 dpm5 cpm5 cpm
2 mg. solids2 mg. solids18 dpm18 dpm8 cpm8 cpm
3 mg. solids3 mg. solids27 dpm27 dpm8 cpm8 cpm
How absorption related to thicknessaffects counting efficiency
Detector DetectorDetector
Energy
Each radionuclide emits specific energies.
Energies are expressed in keV or MeV.
and emitting radionuclides have discrete energies
emitting radionuclides have a continuous spectrum of energies
energies are for the most part distinctly higher than energies
Energy - Implications
Energy spectrometry allows identification of or emitters
Energy “windows” can be set to look at only the energies of interest
1
10
100
1000
10000
100000
1000000
0 500 1000 1500 2000 2500 3000
Energy (keV)
Co
un
ts (
#)
Gamma Spectrum – fish from North Sea and Irish Sea
Beta+ Spectrum From Cu-64
RadiationRadiationInteractionsInteractions
IonizationIonization
IonizationIonization
Radiation interactions
Transfer of energy to electrons and particles
Continuous interaction through matter Gradual loss of energy Definite range
rays Interactions are probabilistic May transfer all or part of energy
Radiation interactions
and particles Continuous interaction through matter Gradual loss of energy Definite range
e-
e-
e-
Radiation interactions
rays Photoelectric, Compton, Pair Production Interactions are probabilistic May transfer all or part of energy
e-e-
e-
Radiation interactions - implications
Ionization may result in electrical pulse, light pulse, or electron hole pairs Pulse size proportional to energy released
and particles All energy released in detector Pulse is proportional to energy of radiation
rays If all energy transferred, pulse is proportional
to energy of radiation
Drinking WaterDrinking Water
MCLsMCLs
MEASURING RADIATIONMEASURING RADIATION
RADIATIONRADIATION SOURCESOURCERADIATIONRADIATION SOURCESOURCE
ROENTGEN (R) the energy of radiation
REM biological dose equivalent
RAD radiation energy absorbed by any material
1 R 1 R 1 R 1 R 1 RAD1 RAD1 RAD1 RAD 1 REM1 REM1 REM1 REM
AVERAGE ANNUAL EXPOSUREAVERAGE ANNUAL EXPOSURE
70 mREM70 mREM70 mREM70 mREM 300 mREM300 mREM300 mREM300 mREM
NATURALLYOCCURRINGNATURALLYOCCURRING
HUMAN-MADEHUMAN-MADE
Basis for Radionuclide MCL’s
Risk is based on amount of radiation, not mass of radioactive material
Most concentration limits stated as activity rather than mass.
Activity not measured directly Can use radiation emitted to
determine the activity.
MCL Ra-226 + Ra-228
Ra-226 + Ra-228 MCL = 5 pCi/L
Equivalent to:5x10-12 g/L Ra-2261.8x10-14 g/L Ra-228
MCL – Gross Alpha
Gross Alpha Excludes Uranium and Radon Includes Radium MCL = 15 pCi/L
MCL – Uranium
Uranium
MCL expressed in mass concentration
MCL = 30 ug/L
MCL – Man-Made Beta and Gamma Emitters
Man-Made Beta and Gamma Emitters
MCL expressed in exposure to people drinking the water
MCL = concentration that would result in 4 mrem/yr
Assumes 2 L/day consumption Assumes 70 kg person
MCL – Man-Made Beta and Gamma Emitters
H-3 and Sr-90 MCLs specified in 40 CFR 141.66 H-3 = 20,000 pCi/L Sr-90 = 8 pCi/L
Others are calculated Examples Cesium-137 = 200 pCi/L Iodine-131 = 3 pCi/L Carbon-14 = 2,000 pCi/L
AnalysisAnalysis
Factors in determining concentration
Count rate Counter Efficiency Geometry Self-absorption Intensity (# of rays per
disintegration) Half-life Sample mass
Analysis Against MCLs Use radiation emitted to determine the
quantity of material. Measure counts per minute or per second Convert to disintegrations per minute
(dpm) or disintegrations per second (dps) Counter efficiency Geometry Emissions per disintegration (intensity) Self-absorption
Convert to pCi Half-life correction Determine concentration
Analysis Against MCLs
Count rate found by detector (cpm)
DetectorSensitivity
Radiation emissionRate (pm)
AnalysisActivity
(dpm) pCi
CollectionActivity
(pCi)
Geometry Intensity
Self-Absorption Sample
Size
Decay
SampleConcentration
Summary
Ionization allows detection Counting technology is determined
by properties of radiation MCLs are based on activity
concentration Radiochemistry vocabulary and
technology are different from chemical methods
Radiation Safety
John Lorenz
Minnesota Department of HealthPublic Health Laboratory
What we’ll cover
Radiation Basics - Review Radiation Health Effects Radiation Sources in the Lab Protecting Yourself from Radiation Protecting Yourself from
Contamination Regulatory requirements
What has formed our opinions about radiation?
BasicsBasicsOfOf
RadiationRadiation
IONIZING vs. NON-IONIZINGIONIZING vs. NON-IONIZING
LIGHTLIGHT
MICRO- WAVESMICRO- WAVES
HEATHEAT
NUCLEAR RADIATIONNUCLEAR RADIATION
}
}
NON-NON-IONIZINGIONIZING
IONIZING IONIZING +
-
HEATING
IONIZATION
Activity Units
Curie (Ci) 3.7x1010 disintegrations per
second Microcuries (Ci) Nanocuries (nCi) Picocuries (pCi)
Becquerels (Bq) 1 disintegration per second Megabecquerels
MEASURING RADIATIONMEASURING RADIATION
RADIATION SOURCERADIATION SOURCE
ROENTGEN (R) the energy of radiation
ROENTGEN (R) the energy of radiation
REM biological dose equivalent
REM biological dose equivalent
RAD radiation energy absorbed by any material
RAD radiation energy absorbed by any material
1 R 1 R 1 RAD1 RAD 1 REM1 REM
AVERAGE ANNUAL EXPOSUREAVERAGE ANNUAL EXPOSURE
70 mREM70 mREM 300 mREM300 mREM300 mREM300 mREM
NATURALLYOCCURRINGNATURALLYOCCURRING
HUMAN-MADEHUMAN-MADE
NATURAL SOURCESNATURAL SOURCES
TERRESTRIAL
COSMIC
MEDICALMEDICAL
INDUSTRIALINDUSTRIALCONSUMER CONSUMER PRODUCTSPRODUCTS
POWER POWER GENERATIONGENERATION
Sources of Radiation – U.S.
Exposure limits
Radiation Workers Radiation Workers 5,000 mrem/yr5,000 mrem/yr
General publicGeneral public100 mrem/yr100 mrem/yr
Declared Pregnant WorkersDeclared Pregnant Workers500 mrem/pregnancy500 mrem/pregnancy
Radiation Radiation Health Health EffectsEffects
RADIATION EXPOSURERADIATION EXPOSURE
ACUTE DOSEACUTE DOSE: : largelarge dose withindose within short periodshort periodACUTE DOSEACUTE DOSE: : largelarge dose withindose within short periodshort period
CHRONIC DOSECHRONIC DOSE: : small or continuoussmall or continuous dose over long perioddose over long periodCHRONIC DOSECHRONIC DOSE: : small or continuoussmall or continuous dose over long perioddose over long period
12 1
2
3
4567
8
9
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RADIATION EFFECTSRADIATION EFFECTS
SOMATIC EFFECTSSOMATIC EFFECTS: : those effects on the exposedthose effects on the exposed individualindividual
GENETIC EFFECTSGENETIC EFFECTS: : those effects on the futurethose effects on the future generations of the exposedgenerations of the exposed individualindividual
RADIATION EFFECTS
Cell DeathCell Death Cell RepairCell Repair Incomplete RepairIncomplete Repair
RADIATION EFFECTSRADIATION EFFECTS
< 10,000 MREM NO DETECTABLE EFFECTS < 10,000 MREM NO DETECTABLE EFFECTS
50,000 MREM DETECTABLE BLOOD CHANGES 50,000 MREM DETECTABLE BLOOD CHANGES
100,000 MREM ONSET OF RADIATION SICKNESS 100,000 MREM ONSET OF RADIATION SICKNESS
600,000 MREM FATAL WITH NO MEDICAL ATTENTION600,000 MREM FATAL WITH NO MEDICAL ATTENTION
OBSERVABLE EFFECTS NOT IDENTIFIED
EFFECTS MASKED WITHIN OTHER HEALTH EFFECTS
KEEP EXPOSURE AS LOW AS REASONABLE
LOW LEVEL RADIATION
RadiationRadiationSourcesSourcesIn TheIn TheLabLab
Radiation sources in the lab
AssumeAll the MN Public Health Lab’s
radioactive materialIn your office (1 meter from you)For one working year
Your exposure will be less than 50 mrem
ProtectingProtectingYourself Yourself FromFromRadiationRadiation
EXPOSURE vs. EXPOSURE RATEEXPOSURE vs. EXPOSURE RATE
1 HOUR
2 HOURS
4 HOURS
8 HOURS
100 mR
200 mR
400 mR
800 mR
100 mR
HR
•EXPOSURE IS THE TOTAL AMOUNT •EXPOSURE IS THE TOTAL AMOUNT
•EXPOSURE RATE IS THE AMOUNT PER UNIT TIME•EXPOSURE RATE IS THE AMOUNT PER UNIT TIME
EXPOSURE R A T E
EXPOSURE R A T E
E
XPOSU
RE
E
XPOSU
RE
S
TAYTI
ME
S
TAYTI
ME
TIME vs. EXPOSURETIME vs. EXPOSURE
1 HOUR
2 HOURS
4 HOURS
8 HOURS
100 mR
200 mR
400 mR
800 mR
RADIATIONRADIATION SOURCESOURCE
1 FOOT
100 mR/hr
E
XPOSU
RE
E
XPOSU
RE
S
TAYTI
ME
S
TAYTI
ME
DISTANCE vs. EXPOSURE
EE XX PP OO SS UU RR EE
RADIATIONRADIATION SOURCESOURCE
5 FEET5 FEET
2 FEET2 FEET
1 FOOT1 FOOT
EECCNNAATTSSIIDD
4 mR4 mR
25 mR25 mR
100 mR100 mR
SHIELDING vs. EXPOSURE
EEXXPPOOSSUU
RR
EE
SS
HHIIEELLDDIINNGG
Radiation Transmittance
alphaalpha
betabeta
gammagamma
PaperPaper PlasticPlastic LeadLead
ProtectingProtectingYourself FromYourself FromContaminationContamination
RADIOLOGICAL CONTAMINATIONRADIOLOGICAL CONTAMINATION
RADIOLOGICAL CONTAMINATION IS
RADIOACTIVE MATERIAL
PRESENT IN AN UNDESIRABLE LOCATION
RADIOLOGICAL CONTAMINATION IS
RADIOACTIVE MATERIAL
PRESENT IN AN UNDESIRABLE LOCATION
CONTAMINATIONCONTAMINATION
NOT SO GOODNOT SO GOOD
RADIOACTIVE LIQUID
RADIOACTIVE LIQUID
GOODGOOD
WHY IS CONTAMINATION A CONCERN?WHY IS CONTAMINATION A CONCERN?
Exposure continues until contamination is removed
Contamination can spread to other people and objects
Contamination can enter the body through ingestion, inhalation, skin absorption, or open wound absorption
Exposure continues until contamination is removed
Contamination can spread to other people and objects
Contamination can enter the body through ingestion, inhalation, skin absorption, or open wound absorption
CONTAMINATION CONTROLCONTAMINATION CONTROL
BOUNDARIES
PROTECTIVE CLOTHING
REMOVAL & SEGREGATION
COVERINGS
BOUNDARIES
PROTECTIVE CLOTHING
REMOVAL & SEGREGATION
COVERINGS
RegulatoryRegulatoryRequirementsRequirements
Regulatory Authority
Nuclear Regulatory CommissionNuclear Regulatory Commission- 10 CFR 19- 10 CFR 19- 10 CFR 20- 10 CFR 20- Specific License- Specific License- General Licenses- General Licenses
Agreement StatesAgreement States- Comparable State Regulations- Comparable State Regulations- State Licenses- State Licenses
Required Postings
10 CFR 19.11 or equivalent requires posting of NRC Form 3 or equivalent 10 CFR 19 and 10 CFR 20 License and License conditions Operating procedures related to
licensed activities Violation notices
Required Postings
Required for rooms housing more than: 10,000 Ci H-3; 100 Ci Cs-137; 1 Ci Ra-226 0.001 Ci Am-241
CautionRadioactive Materials
Required Postings – Greater Hazards
CautionRadiation Area
CautionHigh Radiation Area
Grave DangerVery High Radiation Area
CautionRadioactive
Materials
Cs-137
247 pCi
9/18/06
Labeling
Required for containers holding more than: 1,000 Ci H-3; 10 Ci Cs-137; 0.1 Ci Ra-226 0.001 Ci Am-241
CautionRadioactive
Materials
Cs-137
247 pCi 0.01 R/hr
9/18/06
Radiation Dosimetry
Required if more than 10% of exposure limit is likely
May be specified in license
Worn on trunk of body
Radiation Surveys
Frequency specified by license
Trained personnel
Appropriate instrumentation
Other Requirements
Training – according to license
Emergency procedures
Audits
Inventory, receipt and disposal
Recordkeeping
Summary
Everyone is exposed to radiation
Environmental radiochemistry uses low activities
Exposures should be kept ALARA
Postings and labels indicate where radiological hazards may be present
State and federal regulations and licenses define radiation protection requirements