proficiency test spil-1 (2014) - eurofins scientific
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Quality Documentation
May 2014
Proficiency test SPIL-1 (2014) Organic matter, phosphorus, chloride, sulphate and suspended matter in wastewater (effluent)
Proficiency test SPIL-1 (2014) Quality Documentation May 2014
Eurofins Miljø A/S Smedeskovvej 38 DK-8464 Galten Denmark Tlf: +45 7022 4266
Fax: +45 7022 4255
e-mail: [email protected]
Web: www.eurofins.dk
Client
Environmental laboratories
Client’s representative
Project
Proficiency test SPIL-1 (2014)
Project No
20404-41
Authors
Maj-Britt Fruekilde
Date 2014-05-28
Approved by Stine Kjær Ottsen
Quality Documentation Report MBF SJN 20140528
Revision Description By Approved Date
Key words Analytical quality, assigned value, precision, trueness, homogenity, stability, COD, BOD5 (w. ATU), NVOC/TOC, total phosphorus, chloride, sulphate, suspended matter, wastewater
Classification
Open
Internal
Proprietary
Distribution
DANAK Eurofins:
Maj-Britt Fruekilde, Stine Kjær Ottsen
CONTENTS
1 INTRODUCTION ........................................................................................................... 1
2 FEATURES OF THE PROFICIENCY TEST .................................................................. 2
2.1 Sample preparation ....................................................................................................... 2
2.2 Statistical analysis of participants’ data ......................................................................... 2
2.3 Assigned and spike value .............................................................................................. 2
2.3.1 Assigned and spike values ............................................................................................ 3
2.3.2 Test of spike values ...................................................................................................... 3
2.3.3 Test of assigned values ................................................................................................. 4
3 HOMOGENEITY AND STABILITY OF SAMPLES ......................................................... 5
4 CONCLUSION .............................................................................................................. 6
5 REFERENCES ............................................................................................................. 7
ANNEX A LIST OF PARTICIPANTS ................................................................................... 11
ANNEX B SAMPLE PREPARATION .................................................................................. 13
ANNEX C CONTROL OF SPIKE VALUES ......................................................................... 15
ANNEX D CONTROL OF RECOVERY ............................................................................... 23
ANNEX E CONCENTRATION LEVEL ................................................................................ 31
ANNEX F HOMOGENEITY AND STABILITY ..................................................................... 32
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1 INTRODUCTION
A proficiency test on the analysis of organic matter, phosphorus, chloride, sulphate and suspended matter in wastewater was conducted on 13 March 2014. The proficiency test was organised by Eurofins Miljø A/S.
The present report contains Eurofins’ documentation for the quality of the proficiency test. Results of the proficiency test including data from participating laboratories and statistical analysis of these data were issued in a report to all participants /1/ on 10 April 2014.
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2 FEATURES OF THE PROFICIENCY TEST
Participants in the proficiency test were a total of 72 laboratories from Denmark, Nor-way and Sweden. Some laboratories participated with more than one participant. One of the registered laboratories did not submit results. A list of participants is shown in Appendix A.
The closing date for submission of results was 27 March 2014. All participants had submitted their results before the dead-line.
2.1 Sample preparation
The parameters covered in the proficiency test are listed in Table 2 as are the abbrevi-ations used in this report.
Eight samples were dispatched for the proficiency test. The samples were sample pairs covering the parameters as described in Table 1. The matrix of the samples represent-ed wastewater, in this case effluent. Sample preparation is described in Appendix B.
Table 1 Samples in the proficiency test
Sample name Parameters A1/B1 CODCr/NVOC CODCr, NVOC A1/B1 BOD BOD5, BOD7 A2/B2 TP, Cl, SO4 A3/B3 TSS
2.2 Statistical analysis of participants’ data
A split-level design was used. The data analysis was performed in accordance with ISO 5725: “Accuracy (trueness and precision) of measurement methods and results” (1994) /2/ and as described in detail in Spliid (1992) /3/. A short introduction to the sta-tistics and a list of symbols and abbreviations used is given in Eurofins document “Schedule for a proficiency test”, which is available at Eurofins’ home page /4/.
The statistical model used is based on the assumption that the variances for the two samples in a sample pair are identical. The assumption was tested (F-test, 95% confi-dence level) and the result was that the two variances may be assumed to be identical for all parameters.
2.3 Assigned and spike value
An overview of the concentrations in the samples (the assigned values) and the differ-ence in concentration between the two samples of a sample pair (spike value) are shown in Table 2 compared to the range of concentrations normally encountered in effluent. The table also gives the expanded uncertainty of the assigned values.
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Table 2 Assigned and spike value
Parameter Abbreviation Unit Typical Range
Assigned value
Uncertainty of assigned value
Spike value
Chemical oxygen de-mand
CODCr mg/L O2 5 - 75 35 2.2 4
Five days biochemical oxygen demand
BOD5 (w. ATU) mg/L O2 2 - 6 4.1 0.32 0.8
Seven days biochem-ical oxygen demand
BOD7 (w. ATU) mg/L O2 2 - 6 4.8 0.35 0.8
Non-volatile/total or-ganic carbon
NVOC/TOC mg/L C 2 - 30 14.0 1.2 1.5
Total phosphorus TP mg/L P 0.2 - 2 1.17 0.017 0.14 Chloride Cl mg/L 50 - 700 451 6.7 33 Sulphate SO4 mg/L 20 - 200 94 1.8 12 Suspended matter TSS mg/L 20 - 100 64.4 0.82 7.4
2.3.1 Assigned and spike values The content of each parameter in each sample is given an assigned value for the sam-ple with the lower content and a spike value, the spike value being the difference in concentration between the two samples of the sample pair.
In order to ensure optimal use of the data, the assigned value is calculated as the av-erage of the median for both samples in the sample pair after subtraction of the spike value. The spike values are calculated from sample preparation.
The assigned values for all parameters except Cl and SO4 are operationally defined and are consensus values based upon the median for method no. 6, 76, 76A 77, 77A 91, 92 (CODCr), method no. 1 (NVOC), method no. 1 and 2 (TP), or method no. 2 (TSS), which are the methods required by the Danish EPA /5/. Assigned values for BOD are based upon standardised methods (method no. 1 - 4). A list of method identi-fication numbers is found in the report to participants /1/. Assigned values for Cl and SO4 are consensus values for all laboratories based on the median.
The number of significant figures of the spike and assigned values are determined by the uncertainty of the assigned value: The first decimal place of the uncertainty being the last decimal place of the spike and assigned values.
The uncertainty of the assigned value for NVOC is 1.2, indicating that the spike value and the assigned value should be specified as an integer. However, the spike value for NVOC is designed to 1.5, and rounding the spike value to either 1 or 2 will introduce significance on both the spike value and the assigned value. Hence the assigned value and the spike value for NVOC are given with one decimal.
2.3.2 Test of spike values A comparison was made (t-test, 95% confidence level) between the spike value and the difference in concentration between the two samples in the sample pair found from the laboratories’ results, see Appendix C. The test showed no significant difference be-tween the two for most parameters. The test revealed a significant difference between the two for TP. However, the difference is numerically small and has insignificant influ-ence on the general quality of analyses estimated from the data as well as on the eval-uation of accuracy of participating laboratories.
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2.3.3 Test of assigned values The assigned value and the average of the results obtained from all laboratories were also compared (t-test, 95% confidence level), see Appendix D. The test showed no significant difference between the two and the control of assigned value at Eurofins confirmed the value (Appendix E).
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3 HOMOGENEITY AND STABILITY OF SAMPLES
The homogeneity and stability of samples were tested using the following parameters as indicators:
NVOC Homogeneity test
TP Combined homogeneity and stability test
TSS Combined homogeneity and stability test
The results of control measurements are shown in Appendix F. The appendix also gives the results of the statistical evaluation of the control data. The data are analysed by analysis of variance (ANOVA) giving:
1. the standard deviation/variance for replicates (the contribution from analytical variability),
2. the between bottle standard deviation/variance (the contribution from heterogeneity) and
3. the between days concentration difference (the contribution from in-stability).
Homogeneity is evaluated by comparing the between bottle variance to 0.3 * the standard deviation for evaluation of participants’ performance ( ) specified by the Danish EPA /5/, whereas the stability is evaluated by comparing the concentration change of the samples to . This test ensures that heterogeneity and instability will not have negative influence on the evaluation of participant performance /6/.
The appendix also shows the standard deviation within and between laboratories from the proficiency test to allow comparison between tests performed and average quality from participating laboratories.
The tests for stability and homogeneity show that the samples are stable and homoge-neous.
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4 CONCLUSION
The quality control performed, including test of sample stability and homogeneity as well as test of recovery of spike and assigned values, shows that the samples and their assigned values are suitable for testing the proficiency of the participating laboratories for all parameters. The results are also suitable for estimation of the general quality of analyses among all participating laboratories.
For TP the participants could not recover the spike value. The difference between the calculated spike value and that found by the participants is small and the influence on evaluation of participant performance or estimation of general quality of analyses is in-significant.
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5 REFERENCES
/1/ Eurofins A/S, Proficiency test SPIL-1 (2014), Report to participants, April 2014.
/2/ ISO 5725-2, Accuracy (trueness and precision) of measurement methods and re-sults – Part 2: Basic method for the determination of repeatability and reproduci-bility of a standard measurement method, 1994.
/3/ Spliid, H., Procedure and analysis of data for proficiency tests and environmental analyses, Report to Danish Environmental Protection Agency, 1994 (in Danish).
/4/ Eurofins A/S, Schedule for a proficiency test, document may be downloaded from www.eurofins.dk/proficiencytest.
/5/ Ministry of Environment regulation no. 231 on quality criteria for environmental measurements, 5 March 2014 (in Danish).
/6/ ISO 13528, Statistical methods for use in proficiency testing by interlaboratory comparison, 2005.
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A N N E X E S
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ANNEX A LIST OF PARTICIPANTS
Laboratory Town Country AquaDjurs - Fornæs Renseanlæg Grenaa Denmark Bjergmarken R/A, Roskilde Forsyning Roskilde Denmark CP Kelco ApS, Spildevandslaboratoriet Ll. Skensved Denmark Esbjerg Forsyning Spildevandslaboratorium Esbjerg Denmark Esbjerg Forsyning Spildevandslaboratorium Esbjerg Denmark Eurofins Miljø A/S Vejen Denmark Faxe Forsyning Faxe Denmark Faxe Forsyning Faxe Denmark FORCE LabVest Holstebro Denmark Greve Solrød Forsyning Greve Denmark Halsnæs Kommunale Forsyning A/S Liseleje Denmark Hedensted Spildevand A/S Daugård Denmark Hedensted Spildevand A/S Daugård Denmark Hillerød Forsyning Spildevand A/S Hillerød Denmark Holstebro Centralrenseanlæg, Vestforsyning A/S Holstebro Denmark Kerteminde Forsyning - Spildevand A/S Kerteminde Denmark Kolding Spildevand A/S Bjert Denmark Køge-Egnens Renseanlæg Køge Denmark Mølleåværkets Driftslaboratorium Lyngby Denmark Nyborg Renseanlæg Nyborg Denmark Næstved Centralrenseanlæg Næstved Denmark Provas Haderslev Forsyningsservice A/S Haderslev Denmark Randers Spildevand A/S Randers NØ Denmark Ringkøbing-Skjern Forsyning A/S, Spildevand Skjern Denmark Ringsted Renseanlæg Ringsted Denmark Rønne Renseanlæg Rønne Denmark SK Forsyning, Slagelse Renseanlæg Slagelse Denmark SK Forsyning, Slagelse Renseanlæg Slagelse Denmark SK Forsyning, Slagelse Renseanlæg Slagelse Denmark SK Forsyning, Slagelse Renseanlæg Slagelse Denmark SK Forsyning, Slagelse Renseanlæg Slagelse Denmark Svendborg Centralrenseanlæg Skårup Fyn Denmark Sønderborg Forsyning Sønderborg Denmark Vandrens - Stigsnæs Industripark A/S Skælskør Denmark Vejle Spildevand A/S Vejle Denmark Vores Rens Lynettefællesskabet A/S København K Denmark Eurofins Environment Testing Norway AS Moss Norway AB Borlänge Energi, Reningsverket Borlänge Sweden AB Lennart Månsson International Helsingborg Sweden Akzo Nobel Functional Chemicals AB Cellulosic Specialties QHSE Örnsköldsvik Sweden
Ernemar Laboratoriet Oskarshamn Sweden Eurofins Environment Testing Sweden AB Lidköping Sweden Fiskeby Board AB Norrköping Sweden GRYAAB AB Göteborg Sweden Holmen Paper Norrköping Sweden Holmen Paper AB Hallstavik Sweden Iggesund Paperboard, Cell & Miljölab Iggesund Sweden Ineos Sweden AB Stenungsund Sweden
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Laboratory Town Country Kalmar Vatten AB, VA-lab, Avloppsreningsverket Kalmar Sweden Kristianstad Kommun Kristianstad Sweden Käppalaverket Lidingö Sweden MittSweden Vatten AB, Fillanverket lab. Sundsvall Sweden Mjölby Kommun Mjölby Sweden Motala Kommun Motala Sweden Nordic Sugar Eslöv Sweden NSVA/Öresundsverket Helsingborg Sweden Perstorp Oxo AB Stenungsund Sweden Preem AB Göteborg Göteborg Sweden Preemraff Lysekil Lysekil Sweden Reningsverket Aggerud Karlskoga Sweden Rottneros Bruk AB Rottneros Sweden SAKAB AB Kumla Sweden Smurfit Kappa Kraftliner Piteå Sweden St1 Refinery AB Göteborg Sweden Stora Enso Printing and Reading Hyltebruk Sweden Södra Cell AB Mönsterås Mönsterås Sweden Södra Cell AB, Värö Väröbacka Sweden Tekniska förvaltningen, Verksamhetsstöd VA, Laboratoriet Örebro Sweden Uddebo Laboratorium Luleå Sweden Vallviks Bruk AB Vallvik Sweden VIVAB Varberg Sweden Västerviks Miljö & Energi AB, Vattenlaboratoriet Västervik Sweden
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ANNEX B SAMPLE PREPARATION
Stock solution Prepared from Concentration Concentrate A1 17.70 g D-glucose
17.70 g L-glutamic acid milli-Q water up to 24.00 kg
CODCr: 1.508 g/kg NVOC: 0.596 g/kg BOD: 1.033 g/kg
Concentrate B1 12.00 g D-glucose 12.00 g L-glutamic acid milli-Q water up to 13.00 kg
CODCr: 1.888 g/kg NVOC: 0.746 g/kg BOD: 1.292g/kg
Stock TP 1.5002 g Na-B.glycerophosphate milli-Q water up to 1000.0 g
TP: 151.8 mg/kg
Stock Cl 10.0020g Sodium chloride (NaCl) milli-Q water up to 1000.0 g
Cl: 6.068 g/kg
Stock SO4 5.0044 g Sodium sulphate (Na2SO4) milli-Q water up to 1000.0 g
SO4: 3.384 g/kg
Stock TSS 30.00 g Microcrystalline cellulose milli-Q water up to 2000.0 g
TSS: 15.000 g/kg
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Sample Sample prepared from CODCr mg/L O2
NVOC mg/L C
BOD (w. ATU) mg/L O2
TP mg/L P
Cl mg/L
SO4 mg/L
TSS mg/L
A1-COD/NVOC
At the laboratory 1.00 mL of concen-trate A1 is diluted up to 100.0 mL with filtered water from Esbjerg Vest sew-age treatment plant
a + 15.1 b + 6.0
B1-COD/NVOC
At the laboratory 1.00 mL of concen-trate B1 is diluted up to 100.0 mL with filtered water from Esbjerg Vest sew-age treatment plant
a + 18.9 b + 7.5
A1-BOD At the laboratory 6.00 mL of concen-trate A1 is diluted up to 2000.0 mL with filtered water from Esbjerg Vest sewage treatment plant
c + 3.1
B1-BOD At the laboratory 6.00 mL of concen-trate B1 is diluted up to 2000.0 mL with filtered water from Esbjerg Vest sewage treatment plant
c + 3.9
A2 40.0g stock PO4 250.4 g stock Cl 150.0 g stock SO4 Sample B2 up to 40.0 kg
0.989·
( d+1.08) + 0.152
0.989· ( e+22.2) +
38.0
0.989· (f+9.70) +
12.7
B2 500.0 g stock PO4 256.6 g stock Cl 200.7 g stock SO4 filtered water from Esbjerg Vest sewage treatment plant up to 70.0 kg
d + 1.08 e + 22.2 f + 9.70
A3 At the laboratory 1000.0 mL of filtered water from Esbjerg Vest sewage treatment plant is added to 4.5 mL stock TSS
g + 67.2
B3 At the laboratory 1000.0 mL of filtered water from Esbjerg Vest sewage treatment plant is added to 5.0 mL stock TSS
g + 74.6
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ANNEX C CONTROL OF SPIKE VALUES
CODCr, mg/L O2 Control of differences within sample pairs
Laboratory Difference AB
1 - 2 - 3 2.00 4 3.00 5 - 6 6.50 7 0.00 8 -7.00 9 2.30
10 3.95 11 0.80 12 - 13 4.40 14 4.00 15 - 16 2.40 17 0.20 18 -0.80 19 - 20 -3.30 21 -
22A 0.70 22B 2.00
23 - 24 2.00
25A - 25B -
26 -0.10 27 0.70 28 -0.70 29 -1.00 30 - 31 3.60 UG 32 -
33A 0.00 33B -1.20
34 -4.20 35 1.30 36 - 37 -0.90 38 -1.10 39 1.60 40 1.20 41 -1.00 42 0.70 43 -0.20 44 - 45 6.00 46 - 47 -0.60 48 -
49 -8.20 50 3.47 51 -1.30 52 1.20 53 0.50 54 0.40 55 1.30 56 1.80 57 -2.10 58 1.80 59 2.00 60 - 61 -0.50 62 1.10 63 - 64 - 65 - 66 - 67 43.40 UC 68 - 69 1.80 70 2.00 71 1.50 72 1.40
No of labs., p 51 No of repl., n 2
d 0.62 s² 6.92 s 2.63
t = √p · (d/s) 1.6936 Sign. level, p(t) 0.0966 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
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BOD5 w. ATU, mg/L O2 Control of differences within sample pairs
Laboratory Difference AB
1 - 2 - 3 0.970 4 - 5 - 6 - 7 - 8 - 9 -
10 - 11 - 12 0.220 13 - 14 - 15 - 16 - 17 -0.300 18 - 19 - 20 0.250 21 -
22A - 22B -
23 - 24 0.730
25A - 25B -
26 - 27 - 28 - 29 - 30 - 31 -1.170 32 -
33A 0.800 33B 0.650
34 - 35 - 36 - 37 - 38 - 39 -0.160 40 - 41 - 42 - 43 - 44 - 45 0.200 46 - 47 0.180 48 - 49 0.780 50 - 51 - 52 - 53 -
54 - 55 - 56 - 57 0.600 58 -0.700 59 0.660 60 - 61 - 62 - 63 - 64 - 65 - 66 - 67 - 68 - 69 0.140 70 -0.150 71 - 72 -
No of labs., p 17 No of repl., n 2
d 0.218 s² 0.333 s 0.577
t = √p · (d/s) 1.5541 Sign. level, p(t) 0.1397 No test statistics were found to be significant
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BOD7 w. ATU, mg/L O2 Control of differences within sample pairs
Laboratory Difference AB
1 - 2 0.110 3 - 4 0.130 5 - 6 - 7 - 8 0.240 9 -
10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 0.100
22A - 22B -
23 - 24 -
25A - 25B -
26 - 27 - 28 - 29 - 30 - 31 - 32 -
33A - 33B -
34 - 35 - 36 0.000 37 - 38 - 39 - 40 -0.010 41 - 42 - 43 - 44 - 45 0.190 46 -0.150 47 - 48 - 49 - 50 - 51 -0.010 52 - 53 -
54 - 55 - 56 - 57 - 58 - 59 - 60 0.620 61 - 62 - 63 - 64 -0.200 65 - 66 0.100 67 - 68 - 69 - 70 - 71 0.170 72 -
No of labs., p 13 No of repl., n 2
d 0.099 s² 0.041 s 0.202
t = √p · (d/s) 1.7693 Sign. level, p(t) 0.1022 No test statistics were found to be significant
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NVOC/TOC, mg/L C Control of differences within sample pairs
Laboratory Difference AB
1 -0.87 2 0.02 3 - 4 0.30 5 - 6 -0.50 7 0.40 8 0.10 9 -
10 -0.25 11 - 12 -7.59 UC 13 - 14 -0.20 15 - 16 -0.40 17 - 18 - 19 -0.23 20 -0.30 21 0.10
22A -0.20 22B -
23 0.40 24 -
25A -0.42 25B -
26 - 27 0.00 28 -1.60 UC 29 0.70 30 - 31 - 32 0.00
33A 0.60 33B -
34 - 35 - 36 -0.30 37 - 38 0.78 UG 39 - 40 - 41 - 42 - 43 - 44 0.60 45 -0.40 46 -0.20 47 0.00 48 0.18 49 - 50 - 51 -0.10 52 0.03
53 - 54 - 55 0.20 56 - 57 - 58 0.30 59 - 60 0.10 UG 61 -0.74 62 0.00 63 -0.40 64 -0.30 65 - 66 0.10 67 - 68 0.10 69 - 70 - 71 0.40 72 -
No of labs., p 36 No of repl., n 2
d -0.04 s² 0.13 s 0.37
t = √p · (d/s) -0.5844 Sign. level, p(t) 0.5627 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
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Total phosphorus, mg/L P Control of differences within sample pairs
Laboratory Difference AB
1 - 2 -0.090 3 -0.030 4 -0.029 5 - 6 -0.020 7 0.000 8 -0.020 9 -0.010
10 0.010 11 -0.010 12 0.000 13 -0.020 14 0.000 15 -0.080 16 -0.020 17 0.000 18 -0.265 UC 19 -0.280 UC 20 -0.010 21 0.000
22A 0.000 22B -0.030
23 0.000 24 0.030
25A 0.000 25B 0.020
26 -0.050 27 -0.010 28 - 29 0.010 30 - 31 0.012 32 -
33A -0.020 33B -
34 0.000 35 0.000 36 0.010 37 -0.030 38 -0.270 UC 39 0.050 40 0.010 41 -0.027 42 0.010 43 -0.020 44 -0.030 45 -0.010 46 0.020 47 -0.014 48 -0.010 49 -0.030 50 -0.110 UC 51 0.000 52 -0.005 53 0.010
54 -0.020 55 -0.620 UC 56 0.000 57 -0.030 58 0.000 59 -0.020 60 0.050 61 -0.000 62 -0.008 63 -0.010 64 0.020 65 -0.018 66 0.030 67 -0.010 68 -0.020 69 0.000 70 0.070 71 -0.030 72 0.000
No of labs., p 64 No of repl., n 2
d -0.007 s² 0.001 s 0.025
t = √p · (d/s) -2.1112 Sign. level, p(t) 0.0387 * * denotes that there is a significant difference (t-test, 5%-level) ** denotes that there is a significant difference (t-test, 1%-level) *** denotes that there is a significant difference (t-test, 0.1%-level) UC denotes a Cochran outlier Difference for sample pair AB is significantly different from 0, and data should be corrected with the differ-ence (in spike value), during execution of Cochran's test.
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Chloride, mg/L Control of differences within sample pairs
Laboratory Difference AB
1 -1.0 2 - 3 7.0 4 - 5 - 6 - 7 -7.0 8 - 9 2.0
10 3.7 11 12.3 12 -2.0 13 14.0 14 - 15 - 16 7.0 17 -3.0 18 - 19 - 20 -6.0 UG 21 -
22A 3.0 22B -11.0
23 - 24 -6.0
25A - 25B -
26 -1.0 27 3.0 28 - 29 -1.0 30 - 31 11.0 32 -0.9
33A - 33B 7.0
34 -4.0 35 -24.0 36 - 37 2.0 38 - 39 -13.0 40 - 41 -2.0 42 - 43 - 44 - 45 -7.0 46 - 47 -1.0 48 - 49 - 50 - 51 - 52 -5.0 53 5.0
54 - 55 -7.5 56 -8.0 UG 57 - 58 0.0 59 16.0 60 - 61 32.1 UC 62 - 63 -0.7 64 - 65 - 66 1.5 67 - 68 -6.0 69 2.0 70 12.0 71 - 72 -
No of labs., p 36 No of repl., n 2
d 0.2 s² 64.0 s 8.0
t = √p · (d/s) 0.1131 Sign. level, p(t) 0.9106 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
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Sulphate, mg/L Control of differences within sample pairs
Laboratory Difference AB
1 -352.00 UC 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 -3.00
10 0.48 11 - 12 - 13 0.40 14 - 15 - 16 -0.90 17 -2.40 18 - 19 - 20 -3.30 21 -
22A -0.90 22B -
23 - 24 -1.90
25A - 25B -
26 - 27 0.10 28 - 29 - 30 - 31 - 32 -
33A - 33B -
34 - 35 3.00 UG 36 - 37 - 38 -7.40 39 0.70 40 - 41 - 42 - 43 - 44 - 45 -2.00 46 - 47 0.90 48 - 49 - 50 - 51 - 52 -1.00 53 -
54 - 55 - 56 - 57 - 58 - 59 - 60 - 61 8.08 62 - 63 1.30 64 - 65 - 66 - 67 - 68 1.40 69 -3.60 70 -3.40 71 - 72 -
No of labs., p 19 No of repl., n 2
d -0.87 s² 9.53 s 3.09
t = √p · (d/s) -1.2216 Sign. level, p(t) 0.2376 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
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Total suspended solids, mg/L Control of differences within sample pairs
Laboratory Difference AB
1 - 2 -2.70 3 -0.40 4 0.30 5 7.18 UG 6 0.30 7 1.20 8 -0.10 9 -
10 -0.60 11 -1.30 12 - 13 - 14 6.90 15 2.90 16 - 17 2.50 18 13.00 UC 19 -2.10 20 -3.60 21 -0.20
22A - 22B -
23 1.20 24 -0.20
25A - 25B -
26 -0.30 27 - 28 2.40 29 1.00 30 - 31 3.70 32 -
33A 1.40 33B -
34 - 35 - 36 0.20 37 -0.90 38 -3.10 39 -1.00
40 0.20 41 5.90 42 - 43 - 44 0.80 45 0.00 46 -0.30 47 0.50 48 -2.10 49 -1.80 50 - 51 4.90 52 -0.60 53 -1.50 54 0.70 55 1.90 56 - 57 0.70 58 -0.50 59 -2.60 60 - 61 - 62 0.40 63 -0.20 64 -0.20 65 -0.01 66 -0.50 67 1.57 68 -0.70 69 0.90 70 -0.20 71 -7.60 UG 72 -
No of labs., p 50 No of repl., n 2
d 0.30 s² 4.24 s 2.06
t = √p · (d/s) 1.0134 Sign. level, p(t) 0.3158 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
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ANNEX D CONTROL OF RECOVERY
CODCr, mg/L O2 Control of recovery, average of results
Laboratory Sample pair AB
1 - 2 - 3 34.20 4 41.30 5 - 6 40.35 7 33.50 8 41.50 9 37.35
10 31.73 11 41.40 12 - 13 21.60 14 37.20 15 - 16 33.30 17 33.50 18 25.30 19 - 20 31.65 21 -
22A 35.85 22B 24.80
23 - 24 28.40
25A - 25B -
26 37.15 27 31.45 28 38.75 29 34.00 30 - 31 63.20 UG 32 -
33A 33.40 33B 33.20
34 30.20 35 29.75 36 - 37 31.95 38 41.15 39 32.90 40 44.10 41 32.30 42 32.95 43 37.10 44 - 45 41.00 46 - 47 34.50 48 -
49 33.70 50 23.75 51 33.95 52 38.00 53 29.65 54 31.60 55 32.70 56 33.50 57 35.55 58 32.30 59 33.00 60 - 61 39.25 62 44.25 63 - 64 - 65 - 66 - 67 108.80 UC 68 - 69 39.00 70 30.30 71 36.75 72 29.90
No of labs., p 51 No of repl., n 2
m 34.23 s² 24.55 s 4.95
Assigned value, µ 35 Recovery, % 97.8 t = √p · (m-µ)/s -1.1042 Sign. level, p(t) 0.2748 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
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BOD5 w. ATU, mg/L O2 Control of recovery, average of results
Laboratory Sample pair AB
1 - 2 - 3 4.585 4 - 5 - 6 - 7 - 8 - 9 -
10 - 11 - 12 4.190 13 - 14 - 15 - 16 - 17 3.420 18 - 19 - 20 3.135 21 -
22A - 22B -
23 - 24 3.935
25A - 25B -
26 - 27 - 28 - 29 - 30 - 31 5.615 32 -
33A 4.900 33B 3.605
34 - 35 - 36 - 37 - 38 - 39 3.570 40 - 41 - 42 - 43 - 44 - 45 4.520 46 - 47 3.960 48 - 49 4.080 50 - 51 - 52 - 53 -
54 - 55 - 56 - 57 3.900 58 4.850 59 5.230 60 - 61 - 62 - 63 - 64 - 65 - 66 - 67 - 68 - 69 4.080 70 4.645 71 - 72 -
No of labs., p 17 No of repl., n 2
m 4.248 s² 0.445 s 0.667
Assigned value, µ 4.1 Recovery, % 103.6 t = √p · (m-µ)/s 0.9159 Sign. level, p(t) 0.3733 No test statistics were found to be significant
25
BOD7 w. ATU, mg/L O2 Control of recovery, average of results
Laboratory Sample pair AB
1 - 2 4.895 3 - 4 4.815 5 - 6 - 7 - 8 4.740 9 -
10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 5.210
22A - 22B -
23 - 24 -
25A - 25B -
26 - 27 - 28 - 29 - 30 - 31 - 32 -
33A - 33B -
34 - 35 - 36 5.170 37 - 38 - 39 - 40 4.375 41 - 42 - 43 - 44 - 45 6.125 46 4.375 47 - 48 - 49 - 50 - 51 5.125 52 - 53 -
54 - 55 - 56 - 57 - 58 - 59 - 60 3.140 61 - 62 - 63 - 64 5.300 65 - 66 3.850 67 - 68 - 69 - 70 - 71 4.815 72 -
No of labs., p 13 No of repl., n 2
m 4.764 s² 0.536 s 0.732
Assigned value, µ 4.8 Recovery, % 99.3 t = √p · (m-µ)/s -0.1762 Sign. level, p(t) 0.8631 No test statistics were found to be significant
26
NVOC/TOC, mg/L C Control of recovery, average of results
Laboratory Sample pair AB
1 16.33 2 13.41 3 - 4 13.74 5 - 6 13.75 7 15.10 8 14.95 9 -
10 14.43 11 - 12 15.93 UC 13 - 14 13.70 15 - 16 13.90 17 - 18 - 19 13.89 20 13.85 21 14.35
22A 15.60 22B -
23 16.60 24 -
25A 14.39 25B -
26 - 27 14.10 28 13.10 UC 29 15.35 30 - 31 - 32 14.40
33A 13.70 33B -
34 - 35 - 36 13.85 37 - 38 22.63 UG 39 - 40 - 41 - 42 - 43 - 44 13.30 45 12.90 46 14.20 47 14.30 48 15.46 49 - 50 - 51 13.25 52 14.21 53 -
54 - 55 14.35 56 - 57 - 58 13.65 59 - 60 5.10 UG 61 14.03 62 14.30 63 13.70 64 12.85 65 - 66 16.55 67 - 68 12.95 69 - 70 - 71 14.10 72 -
No of labs., p 36 No of repl., n 2
m 14.26 s² 0.90 s 0.95
Assigned value, µ 14.0 Recovery, % 101.9 t = √p · (m-µ)/s 1.6686 Sign. level, p(t) 0.1041 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
27
Total phosphorus, mg/L P Control of recovery, average of results
Laboratory Sample pair AB
1 - 2 1.215 3 1.225 4 1.124 5 - 6 1.160 7 1.180 8 1.200 9 1.135
10 1.035 11 1.145 12 1.210 13 1.130 14 1.150 15 1.270 16 1.130 17 1.230 18 1.212 UC 19 1.180 UC 20 1.175 21 1.170
22A 1.170 22B 1.145
23 1.190 24 1.235
25A 1.130 25B 1.200
26 1.085 27 1.145 28 - 29 1.175 30 - 31 1.202 32 -
33A 1.220 33B -
34 1.230 35 1.220 36 1.155 37 1.205 38 1.152 UC 39 1.225 40 1.305 41 1.174 42 1.185 43 1.080 44 1.145 45 1.255 46 1.150 47 1.159 48 1.145 49 1.165 50 1.185 UC 51 1.190 52 1.152 53 1.155
54 1.200 55 1.470 UC 56 1.170 57 1.135 58 1.190 59 1.190 60 1.215 61 1.240 62 1.162 63 1.185 64 1.150 65 1.169 66 1.145 67 1.145 68 1.170 69 1.230 70 1.295 71 1.145 72 1.230
No of labs., p 64 No of repl., n 2
m 1.179 s² 0.002 s 0.048
Assigned value, µ 1.17 Recovery, % 100.8 t = √p · (m-µ)/s 1.4725 Sign. level, p(t) 0.1459 No test statistics were found to be significant UC denotes a Cochran outlier
28
Chloride, mg/L Control of recovery, average of results
Laboratory Sample pair AB
1 441.6 2 - 3 455.5 4 - 5 - 6 - 7 454.5 8 - 9 497.0
10 433.1 11 481.6 12 441.0 13 492.0 14 - 15 - 16 413.5 17 457.5 18 - 19 - 20 334.0 UG 21 -
22A 469.5 22B 430.5
23 - 24 447.0
25A - 25B -
26 464.5 27 425.5 28 - 29 455.5 30 - 31 492.5 32 460.1
33A - 33B 439.5
34 448.0 35 477.0 36 - 37 459.0 38 - 39 459.5 40 - 41 490.5 42 - 43 - 44 - 45 445.5 46 - 47 448.5 48 - 49 - 50 - 51 - 52 484.5 53 449.5
54 - 55 438.8 56 337.0 UG 57 - 58 426.0 59 467.0 60 - 61 435.6 UC 62 - 63 444.0 64 - 65 - 66 446.9 67 - 68 435.0 69 467.0 70 467.0 71 - 72 -
No of labs., p 36 No of repl., n 2
m 455.7 s² 425.6 s 20.6
Assigned value, µ 451 Recovery, % 101.0 t = √p · (m-µ)/s 1.3692 Sign. level, p(t) 0.1797 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
29
Sulphate, mg/L Control of recovery, average of results
Laboratory Sample pair AB
1 444.00 UC 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 96.50
10 97.10 11 - 12 - 13 92.80 14 - 15 - 16 91.45 17 92.20 18 - 19 - 20 93.65 21 -
22A 86.45 22B -
23 - 24 86.55
25A - 25B -
26 - 27 90.95 28 - 29 - 30 - 31 - 32 -
33A - 33B -
34 - 35 125.50 UG 36 - 37 - 38 107.00 39 98.65 40 - 41 - 42 - 43 - 44 - 45 93.00 46 - 47 94.55 48 - 49 - 50 - 51 - 52 95.50 53 -
54 - 55 - 56 - 57 - 58 - 59 - 60 - 61 100.20 62 - 63 91.85 64 - 65 - 66 - 67 - 68 93.30 69 93.80 70 89.70 71 - 72 -
No of labs., p 19 No of repl., n 2
m 93.96 s² 22.51 s 4.74
Assigned value, µ 94 Recovery, % 100.0 t = √p · (m-µ)/s -0.0387 Sign. level, p(t) 0.9696 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
30
Total suspended solids, mg/L Control of recovery, average of results
Laboratory Sample pair AB
1 - 2 66.05 3 66.10 4 64.25 5 72.91 UG 6 66.55 7 64.70 8 63.85 9 -
10 66.41 11 65.05 12 - 13 - 14 59.55 15 65.95 16 - 17 62.25 18 58.60 UC 19 65.05 20 64.80 21 63.20
22A - 22B -
23 65.90 24 64.20
25A 62.20 25B -
26 68.25 27 - 28 64.60 29 64.00 30 - 31 60.45 32 -
33A 64.18 33B -
34 - 35 - 36 64.50 37 66.25 38 60.75 39 61.00 40 65.70 41 61.55 42 - 43 - 44 67.00 45 64.40 46 66.15 47 62.85 48 61.25 49 66.70 50 - 51 61.35 52 63.30 53 64.95
54 65.55 55 63.05 56 - 57 64.65 58 64.55 59 67.30 60 - 61 - 62 65.70 63 65.50 64 64.70 65 65.58 66 63.75 67 64.33 68 61.15 69 63.65 70 63.00 71 53.20 UG 72 -
No of labs., p 50 No of repl., n 2
m 64.31 s² 3.80 s 1.95
Assigned value, µ 64.4 Recovery, % 99.9 t = √p · (m-µ)/s -0.3265 Sign. level, p(t) 0.7454 No test statistics were found to be significant UC denotes a Cochran outlier UG denotes a Grubbs outlier
31
ANNEX E CONCENTRATION LEVEL
Parameter Unit Sample Bottle no. I II Bottle Sample Assigned Spike Average Average value Measured Assigned
COD mg/L O2 A1 23/73 33,10 33,10 33,20 35 -3,37 -4 41/20 33,40 33,40 47/7 33,10 33,10 B1 51/1 36,60 36,60 36,57 39 11/28' 36,90 36,90 56/65 36,20 36,20 Total phosphorus mg/L P A2 38 1,34 1,34 1,33 1,31 0,14 0,14 1 1,33 1,33 95 1,33 1,33 B2 73 1,20 1,20 1,19 1,17 8 1,20 1,20 12 1,18 1,18 Chloride mg/L A2 38 464,00 464,00 453,67 484 36,00 33,00 1 453,00 453,00 95 444,00 444,00 B2 73 418,00 418,00 417,67 451 8 416,00 416,00 12 419,00 419,00 Sulphate mg/L A2 38 103,00 103,00 100,37 106 11,23 12,00 1 104,00 104,00 95 94,10 94,10 B2 73 90,90 90,90 89,13 94 8 85,60 85,60 12 90,90 90,90 Total suspended mg/L A3 66/14 67,00 67,00 66,33 64,4 -7,00 -7,40 solids 38/39 66,00 66,00 58/44 66,00 66,00 B3 32/7 72,00 72,00 73,33 71,8 8/65' 73,00 73,00 58/1 75,00 75,00
32
ANNEX F HOMOGENEITY AND STABILITY
PT:SPIL-1
Parameter:NVOC
Unit:mg/L C
Sigma:0,9247 6,5% level Responsible for tests: IRL/mbf
6,5% level or 1,3*ST max
Homogeneity test Date:2014-02-26 Stability test Date:
Sample x(a) x(b) average sd sd^2 Sample x(a) x(b)
A1-3-87 14,5 14,3 14,4 0,148 0,022
A1-5-76 14,1 13,9 14,0 0,156 0,02
A1-9-61 14,1 14,1 14,1 0,028 0,001
A1-19-47 14,1 14,1 14,1 0,000 0,000
A1-20-64 14,2 14,1 14,2 0,092 0,008
A1-31-100 14,2 14,8 14,5 0,396 0,157 For stability
A1-32-26 14,1 14,2 14,1 0,057 0,003 General average (y):
A1-40-96 14,0 14,1 14,1 0,092 0,008 /x-y/ =
A1-48-11 14,9 13,9 14,4 0,700 0,490
A1-50-1 13,8 13,9 13,9 0,085 0,007
A1-64-27 14,9 14,1 14,5 0,552 0,304
A1-71-38 14,4 14,6 14,5 0,141 0,020 Conclusions
ss = 0,047 0.3*sigma=0,28
For homogeneity /x-y/ =
General average (x) 14,23 Analytical Is sw < 0,15*sigma
Sample average sd (sx) 0,214 quality NO
Within-sample sd (sw): 0,295
Between-samples sd (ss): 0,0470 Homogeneity: Is ss < 0.3*sigma?
SL in the Proficiency Test: YES
SR in the Proficiency Test:
Stability: /x-y/ < 0.3*sigma?
No data
33
PT: SPIL-1
Parameter: TP
Unit: mg/L P
Sigma: 0,0874 6,5% level Responsible for tests: IRL/mbf
6,5% level or 1,3*ST max
Homogeneity test Date: 2014-02-26 Stability test Date: 2014-03-13 IRL
Sample x(a) x(b) average sd sd^2
Sample x(a) x(b) A2-44 1,3 1,4 1,4 0,049 0,002 A2-38 1,34
A2-9 1,3 1,4 1,4 0,057 0,00 A2-1 1,33
A2-69 1,4 1,3 1,4 0,035 0,001 A2-95 1,33
A2-84 1,3 1,3 1,3 0,000 0,000
A2-24 1,3 1,4 1,3 0,021 0,000
A2-892 1,4 1,4 1,4 0,007 0,000 For stability
A2-99 1,3 1,3 1,3 0,035 0,001 General average (y): 1,3333333
A2-40 1,3 1,4 1,3 0,014 0,000 /x-y/ = 0,01125
A2-53 1,4 1,4 1,4 0,007 0,000
A2-69 1,3 1,3 1,3 0,000 0,000
A2-82 1,3 1,3 1,3 0,021 0,000
A2-19 1,4 1,3 1,3 0,014 0,000 Conclusions
ss = 0,000 0.3*sigma= 0,03
For homogeneity /x-y/ = 0,01125
General average (x) 1,34 Analytical Is sw < 0,15*sigma
Sample average sd (sx) 0,018 quality NO
Within-sample sd (sw): 0,028
Between-samples sd (ss): 0 Homogeneity: Is ss < 0.3*sigma?
SL in the Proficiency Test: YES
SR in the Proficiency Test:
Stability: /x-y/ < 0.3*sigma?
YES
34
PT: SPIL-1
Parameter: TSS
Unit: mg/L
Sigma: 4,8 6,5% level Responsible for tests: IRL/mbf
6,5% level or 1,3*ST max
Homogeneity test Date: 2014-02-26 Stability test Date: 2014-03-13 IRL
Sample x(a) x(b) average sd sd^2
Sample x(a) x(b) B3-5-14 73,3 73,3 B3-32-7 72
B3-11-4 73,5 73,5 B3-8-65 73 B3-19-45 68,35 B3-58-1 75 B3-25-64 73,4 73,4 B3-34-21 74,3 74,3 B3-39-52 73,6 73,6 For stability B3-45-71 73,6 73,6 General average (y): 73,333333 B3-52-41 73,9 73,9 /x-y/ = 0,0157576 B3-59-50 71,7 71,7 B3-65-33 73,6 73,6 B3-77-90 71,9 71,9 B3-72-78 73,7 73,7 Conclusions
ss = 0,79 0.3*sigma= 1,43
For homogeneity /x-y/ = 0,0157576
General average (x) 73,3 Analytical Is sw < 0,15*sigma
Sample average sd (sx) 0,792 quality No data
Within-sample sd (sw):
Between-samples sd (ss): 0,792 Homogeneity: Is ss < 0.3*sigma?
SL in the Proficiency Test: YES
SR in the Proficiency Test:
Stability: /x-y/ < 0.3*sigma?
YES
A hole was made in the filter c during preparation B3-19-45