Report No Waters Proficiency Testing Round No. 172 Total...

SD 9.17.08

- Total Solids, Total Suspended Solids,

PTA wishes to gratefully acknowledge the technical assistance provided for this program by Dr M Buckleygo to Global Proficiency Ltd (New Zealand) and to the supply and distribution of the samples.

SD 9.17.08

Waters Proficiency Testing

Total Solids, Total Suspended Solids,

PTA wishes to gratefully acknowledge the technical assistance provided for this program by Dr M Buckley-Smithgo to Global Proficiency Ltd (New Zealand) and to the supply and distribution of the samples.

PO Box 7507

Report No


Round

Total Solids, Total Suspended Solids, Total Dissolved Solids

PTA wishes to gratefully acknowledge the technical assistance provided for this program by Smith and Mrs R Ryan

go to Global Proficiency Ltd (New Zealand) and to the supply and distribution of the samples.

© Copyright

PO Box 7507

Report No


Round


Januar

Acknowledgments

PTA wishes to gratefully acknowledge the technical assistance provided for this program by and Mrs R Ryan, Globa


© Copyright Proficiency Testing Australia

PO Box 7507 SILVERWATER

Report No


Round No.


Januar y 2015

Acknowledgments

PTA wishes to gratefully acknowledge the technical assistance provided for this program by , Global Proficiency Ltd (New Zealand)


Proficiency Testing Australia

SILVERWATER NSW

Report No . 892


o. 172


y 2015

Acknowledgments

PTA wishes to gratefully acknowledge the technical assistance provided for this program by l Proficiency Ltd (New Zealand)

go to Global Proficiency Ltd (New Zealand) and to Global Proficiency Pty Ltd (Australia) for


NSW 2128

892


172

Total Solids, Total Suspended Solids, Total Dissolved Solids -

PTA wishes to gratefully acknowledge the technical assistance provided for this program by l Proficiency Ltd (New Zealand)

Global Proficiency Pty Ltd (Australia) for

Proficiency Testing Australia , 2015

2128, Australia


Total Solids, Total Suspended Solids, -

PTA wishes to gratefully acknowledge the technical assistance provided for this program by l Proficiency Ltd (New Zealand). Also our thanks


2015

, Australia

Total Solids, Total Suspended Solids,

PTA wishes to gratefully acknowledge the technical assistance provided for this program by . Also our thanks


SD 9.17.08

CONTENTS

1. Foreword ............................................................................................................................ 1

2. Program Features and Design ........................................................................................... 1

3. Statistical Format ............................................................................................................... 2

4. PTA and Technical Advisers' Comments ........................................................................... 4

5. Outlier Results ................................................................................................................. 25

6. Reference ........................................................................................................................ 25

APPENDIX A – Results and Data Analysis

Total Solids ............................................................................................................................ A1

Total Suspended Solids ........................................................................................................ A7

Total Dissolved Solids ......................................................................................................... A13

APPENDIX B – Sample Homogeneity and Stability

Homogeneity and Stability Testing ........................................................................................ B1

APPENDIX C – Documentation

Instructions to Participants .................................................................................................... C1

Method Codes ....................................................................................................................... C3

Results Sheet ........................................................................................................................ C4

1

SD 9.17.08

1. Foreword

This report summarises the results of a proficiency testing program on the determination of Total Solids, Total Suspended Solids and Total Dissolved Solids in waters. This is round 172 in a planned series of programs involving the analysis of chemical and physical parameters of waters. The exercise was conducted in October 2014 by Proficiency Testing Australia (PTA). The main aim of the program was to assess laboratories’ abilities to competently perform the prescribed analyses. The Program Coordinator was Mrs D Mihaila and the Technical Advisers were Dr M Buckley-Smith and Mrs R Ryan, Global Proficiency Ltd (New Zealand). This report was authorised by Mrs F Watton, PTA Quality – Business Development Manager.

2. Program Features and Design 2.1 Each laboratory was randomly allocated a unique code number for the program to

ensure confidentiality of results. Reference to each laboratory in this report is by code number only. Please note that a number of laboratories reported more than one set of results and, therefore, their code numbers (with letter) could appear several times in the same data set.

2.2 Laboratories were provided with the "Instructions to Participants" and "Results Sheet"

(see Appendix C). Laboratories were requested to perform the tests according to their routine methods.

2.3 Participants were provided with two plastic vials (labelled PTA 1 and PTA 2)

containing water samples for the analysis of Total Solids, Total Suspended Solids and Total Dissolved Solids.

2.4 A total of 58 laboratories received samples, comprising:

- 42 Australian participants; and

- 16 overseas participants, including:

- Brunei Darussalam (1), Democratic Republic of Congo (1), Indonesia (3), Malaysia (1), New Zealand (1), Nigeria (2), Papua New Guinea (2), Qatar (1), Russia (1), Singapore (1), Thailand (1), Vietnam (1).

Of these 58 laboratories, 3 were unable to submit results by the due date. 2.5 Results (as reported by participants) with corresponding summary statistics (i.e.

number of results, median, normalised interquartile range, uncertainty of the median, robust coefficient of variation, minimum, maximum and range) are presented in Appendix A (for each sample and for each of the analyses performed).

2.6 A robust statistical approach, using z-scores, was utilised to assess laboratories’

testing performance (see Section 3). Robust z-scores and ordered z-score relevant to each test are presented in Appendix A.

2

SD 9.17.08

The document entitled Guide to Proficiency Testing Australia, 2014 (reference [1]) defines the statistical terms and details the statistical procedures referred to in this report.

2.7 A tabulated listing of laboratories (by code number) identified as having outlier results can be found on page 25.

2.8 Prior to sample distribution, a number of randomly selected samples were analysed

for homogeneity and stability. Based on the results of this testing (see Appendix B) it was considered that the samples utilised for this program were homogeneous and stable. As such, any results later identified as outliers could not be attributed to any notable sample variability.

3. Statistical Format

For each test the following information is given:

- a table of results and calculated z-scores;

- a list of summary statistics; and

- ordered z-score charts.

3.1 Outlier Results and Z-scores In order to assess laboratories’ testing performance, a robust statistical approach,

using z-scores, was utilised. Z-scores give a measure of how far a result is from the consensus value (i.e. the median), and gives a "score" to each result relative to the other results in the group.

A z-score with an absolute value less than or equal to 2.0 is considered to be

satisfactory, whereas, a z-score with an absolute value greater than or equal to 3.0 is considered to be an outlier and is marked by the symbol “§”. Laboratories are also encouraged to review results which have an absolute z-score value between 2.0 and 3.0 (i.e. 2.0 < |z-score| < 3.0). These results are considered to be questionable results.

Each determination was examined for outliers with all methods pooled. The table on

page 25 summarises the outlier results detected. 3.2 Results Tables and Summary Statistics The tables in Appendix A contain the results returned by each laboratory, including

the code number for the method used and the robust z-score calculated for each result.

Results have been entered exactly as reported by participants. That is, laboratories

which did not report results to the precision (i.e. number of decimal places) requested on the Results Sheet have not been rounded to the requested precision before being included in the statistical analysis.

3

SD 9.17.08

A list of summary statistics appears at the bottom of each of the results tables and consists of:

- No. of Results: the total number of results for that test/sample;

- Median: the middle value of the results;

- Normalised IQR: the normalised interquartile range of the results;

- Uncertainty of the Median: a robust estimate of the standard deviation of the Median;

- Robust CV: the robust coefficient of variation expressed as a percentage, i.e. 100 x Normalised IQR / Median;

- Minimum: the lowest laboratory result;

- Maximum: the highest laboratory result; and

- Range: the difference between the Maximum and Minimum.

The median is a measure of the centre of the data. The normalised IQR is a measure of the spread of the results. It is calculated by multiplying the interquartile range (IQR) by a correction factor, which converts the IQR to an estimate of the standard deviation. The IQR is the difference between the upper and lower quartiles (i.e. the values above and below which a quarter of the results lie, respectively). For normally distributed data, the uncertainty of the median is approximated by:

��2 ��

√�

� = number of results. Please see reference [1] for further details on these robust summary statistics.

3.3 Ordered Z-score Charts The charts in Appendix A indicate each laboratory's robust z-score, in order of

magnitude, marked with its laboratory code number. From these charts, each laboratory can readily compare its performance relative to the other laboratories.

These charts contain solid lines at +3.0 and -3.0, so that outliers are clearly

identifiable as those laboratories whose "bar" extends beyond these "cut-off" lines. The y-axis of these charts has been limited, so very large z-scores appear to extend beyond the chart boundary.

4

SD 9.17.08

4. PTA and Technical Advisers’ Comments 4.1 Metrological Traceability and Measurement Uncertainty of Assigned Values

Consensus values (median) derived from participants’ results are used in this program. These values are not metrologically traceable to an external reference. Sample preparation was undertaken according to Global Proficiency Ltd’s Standard Operating Procedures to ensure samples were fit-for-purpose, homogeneous and stable. Solutions were stable and homogeneous, and medians obtained from this proficiency round were in consistent agreement with the expected levels (dope concentration), as shown in Table 1. The slight under recovery of Total Suspended Solids results and slight over recovery of Total Dissolved Solids is as expected, due to the particle size distribution in the artificial solids solution. As the assigned value for each analyte in this program is the median of the results submitted by the participants, the uncertainty of the median for each analyte has been calculated and is presented in Table 1 below. Table 1. Comparison of expected levels (dope concentration) and proficiency medians. The values of the calculated uncertainty of the median are also presented.

Analyte Sample Dope

Concentration (mg/L)

Median (mg/L)

Uncertainty of the Median

(mg/L)

Total Solids (TS)

PTA 1 271 275.0 3.3

PTA 2 432 435.0 3.4

Total Suspended Solids (TSS)

PTA 1 70 66.00 0.69

PTA 2 85 82.00 0.88

Total Dissolved Solids (TDS)

PTA 1 201 208.0 2.4

PTA 2 347 356.0 4.1

Overall, the performance of participants in this round was good, with robust CVs below 7% for all analytes.

5

SD 9.17.08

4.2 Analysis of Round 172 Results 4.2.1 Total Solids Table 2 compares the Total Solids median and robust CV from this round to those obtained in previous PTA rounds. Table 2. Comparison of current round variability and proficiency median of Total Solids testing with the results of the previous two rounds.

Round Sample Median (mg/L) Robust CV (%) Participants

This study PTA 1 275.0 6.2 41

PTA 2 435.0 4.0 42

Report 830 PTA 1 371.0 6.2 49

PTA 2 266.0 8.1 49

Report 767 PTA 1 262.5 6.5 56

PTA 2 312.0 4.8 56 Bias / Accuracy The Total Solids testing was successfully performed, with satisfactory results (|z-score| ≤ 2.0) ranging between 241 – 309 mg/L for sample PTA 1 and 401 – 469 mg/L for sample PTA 2. Out of 41 results submitted for sample PTA 1 and 42 results for sample PTA 2, two questionable results (2.0 < |z-score| < 3.0) were reported for sample PTA 1 (laboratories 575 and 607) and four questionable results were reported for sample PTA 2 (laboratories 210, 551, 563 and 575). Three outlier results (|z-score| ≥ 3.0) were obtained for sample PTA 1, requiring follow-up action by laboratories 362b, 498 and 563. Four outlier results were obtained for sample PTA 2, requiring follow-up action by laboratories 310, 362b, 464 and 607. The Total Solids data set formed an approximately normal distribution with no substantial bias attributable to any one method (Figures 1 and 2). The method APHA 2540 B (Total Solids Dried at 103-105ºC - method code 1) was the most popular method choice for Total Solids analysis, being used by approximately 80% of participants for sample PTA 1 and 79% of participants for sample PTA 2. The close agreement between the dope concentration and the median obtained in the round (DopePTA1: 271mg/L, MedianPTA1: 275.0 mg/L and DopePTA2: 432mg/L, MedianPTA2: 435.0 mg/L), gives good confidence in laboratories’ ability to get the right answer. The method APHA 2540 B indicates that the most likely sources of error in this test include insufficient drying and the necessity for rapid weighing to obtain a consistent weight. APHA recommends to limit the sample to no more than 200 mg of residue in the dish, to avoid a water-trapping crust from forming, and carrying out a Method Blank at least once per day or every 20 samples, as a minimum. APHA also recommends that laboratories should randomly select samples to be analysed in duplicate, preparing each of the two samples independently (APHA 2020 B).

6

SD 9.17.08

Figure 1. Spread of results for Total Solids testing of sample PTA 1, with a median of 275.0 mg/L.

Figure 2. Spread of results for Total Solids testing of sample PTA 2, with a median of 435.0 mg/L.

0

2

4

6

8

10

12

14

16

18

20

205 220 235 250 265 280 295 310 325 340 355 370 385 400

Fre

quen

cy

Results (mg/L)

Total Solids - Sample PTA 1

APHA 2540 B

Calculation

Other

0

2

4

6

8

10

12

14

16

18

20

340 360 380 400 420 440 460 480 500 520 540 560 580 600

Fre

quen

cy

Results (mg/L)


APHA 2540 B

Calculation

Other

7

SD 9.17.08

Measurement Uncertainty (MU) The MU reported by participants can be seen in Figures 3 and 4. Out of 41 participants for sample PTA 1 and 42 participants for sample PTA 2, 30 (73% and 71%, respectively) submitted MU information. Several of the stated MUs did not accurately reflect the difference between the median and the participant’s result for these proficiency samples. A t-test of all the results (outliers removed), indicated that the overall reproducibility for Total Solids testing was 275.0 ± 32.7 mg/L for sample PTA 1 and 435.0 ± 38.4 mg/L for sample PTA 2 (95% CI). Thus, a cluster of reported MUs would have been expected in the region of 30-40 mg/L, however the majority of laboratories indicated that their MU was below 30 mg/L. Laboratories 382, 471, 498, 545, 551, 563 and 607 may wish to re-examine their MU calculations, as their result was further from the median than their stated MU for at least one of the samples tested, as shown in Figures 5 and 6.

Figure 3. MU for Total Solids testing of sample PTA 1, as reported by participants, compared with 95% confidence interval for overall reproducibility, ± 32.7 mg/L in this round, shown as a dashed line.

0

1

2

3

4

5

6

7

8

9

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Fre

quen

cy

Measurement Uncertainty (mg/L)

Total Solids ± MU - Sample PTA 1

APHA 2540 B

Calculation

Other

8

SD 9.17.08

Figure 4. MU for Total Solids testing of sample PTA 2, as reported by participants, compared with 95% confidence interval for overall reproducibility, ± 38.4 mg/L in this round, shown as a dashed line.

0

1

2

3

4

5

6

7

8

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Fre

quen

cy


Total Solids ± MU - Sample PTA 2

APHA 2540 B

Calculation

Other

9

SD

9.17.08

Results of sam

ple PT

A 1, including M

U, com

pared to the m

edian

Total S

olids - Sam

ple PT

A 1

Figure 5. Total Solids - Results of sample PTA 1, including MU, compared to the median.

150

200

250

300

350

400

450

50012

6

128

138

183

196

210

237

271

274

286

310

329

350

382

390

398

410

466

471

498

519

545

551

563

568

588

607

633

634

660

Re

sults

(mg/

L)

Laboratory Code


Result ± MU Median Uncertainty of the Median

10

SD

9.17.08

Results of sam

ple PT

A 2, including M

U, com

pared to the m

edian

Total S

olids - Sam

ple PT

A 2

Figure 6. Total Solids - Results of sample PTA 2, including MU, compared to the median.

300

350

400

450

500

550

60012

6

128

138

183

196

210

237

271

274

286

310

329

350

382

390

398

410

466

471

498

519

545

551

563

568

588

607

633

634

660

Re

sults

(mg/

L)

Laboratory Code



11

SD 9.17.08

4.2.2 Total Suspended Solids Table 3 compares the Total Suspended Solids median and robust CV from this round to those obtained in previous PTA rounds. Results for this round were very good. Table 3. Comparison of current round variability and proficiency median of Total Suspended Solids testing with the results of the previous two rounds.



PTA 2 82.00 6.3 55

Report 830 PTA 1 70.00 9.3 68

PTA 2 48.00 9.3 68

Report 767 PTA 1 63.70 6.9 70

PTA 2 78.30 7.3 70 Bias / Accuracy The Total Suspended Solids testing was successfully performed, with satisfactory results (|z-score| ≤ 2.0) ranging between 58.0 – 74.0 mg/L for sample PTA 1 and 71.7 – 92.3 mg/L for sample PTA 2. Out of 54 results submitted for sample PTA 1 and 55 results for sample PTA 2, five questionable results (2.0 < |z-score| < 3.0) were reported for sample PTA 1 (laboratories 117, 237, 329, 342 and 410) and five questionable results were reported for sample PTA 2 (laboratories 271, 410, 466, 553 and 596). Three outlier results (|z-score| ≥ 3.0) were obtained for sample PTA 1, requiring follow-up action by laboratories 323a, 590 and 607. Four outlier results were obtained for sample PTA 2, requiring follow-up action by laboratories 323a, 517, 551 and 590. The Total Suspended Solids data set formed an approximately normal distribution with no substantial bias attributable to any one method (Figures 7 and 8). The method APHA 2540 D (Total Suspended Solids Dried at 103-105ºC - method code 5) was the most popular method choice for Total Suspended Solids analysis, being used by approximately 96% of participants. The most commonly used brands of Glass Filters in the analysis of Solids were Whatman (20), Advantech (6), Millipore (5) and PALL (4). Other brands included Sartorius, Environmental Express ProWeigh, MicroScience, Filtech and Munktell. None of the brands were over-represented between laboratories which obtained outlier results. The nominal filter sizes used included 0.45 micron (8), 1.0 micron (4), 1.2 micron (7), 1.5 micron (4), 1.6 micron (1) and 2.0 micron (2). There were no obvious trends observed, due to insufficient laboratories with outlier results reporting the filter pore sizes used (just the filter diameter). However, the larger nominal filter pore sizes may have contributed to low biasing Total Suspended Solids results. Laboratories with low bias may also wish to look at their sample preparation procedures to obtain a well mixed and homogeneous sample to filter and dry (see homogeneity section for manufacturing precision). The most likely sources of error for laboratories with high bias would be insufficient drying.

12

SD 9.17.08

Figure 7. Spread of results for Total Suspended Solids testing of sample PTA 1, with a median of 66.00 mg/L.

Figure 8. Spread of results for Total Suspended Solids testing of sample PTA 2, with a median of 82.00 mg/L.

0

4

8

12

16

20

24

25 30 35 40 45 50 55 60 65 70 75 80 85 90

Fre

quen

cy

Results (mg/L)

Total Suspended Solids - Sample PTA 1

APHA 2540 D

Other

0

4

8

12

16

20

24

28

20 26 32 38 44 50 56 62 68 74 80 86 92 98

Fre

quen

cy

Results (mg/L)


APHA 2540 D

Other

13

SD 9.17.08

Measurement Uncertainty (MU) The MU reported by participants can be seen in Figures 9 and 10. 76% of participants submitted MU information for sample PTA 1 and 75% of participants for sample PTA 2. Quite a number of the stated MUs did not accurately reflect the difference between the median and the participant’s result for these proficiency samples. Laboratories 237, 271, 310, 329, 334, 382, 410, 466, 499, 519, 551, 607 and 674 may wish to re-examine their MU calculations, as their result was further from the median than their stated MU at least for one of the samples tested, as shown in Figures 11 and 12 below. A t-test of all the results (outliers removed), indicated that the overall reproducibility for Total Suspended Solids testing was 66.00 ± 8.71 mg/L (13%) for sample PTA 1 and 82.00 ± 11.05 mg/L (13%) for sample PTA 2 (95% CI). Thus, we would have expected a larger number of MUs clustered around 7.5-9.0 mg/L for sample PTA 1 in Figure 9, and around 9.0-12.0 mg/L for sample PTA 2 in Figure 10. Laboratories are to be commended, as this reproducibility was less than the 2SD of 20% stated in Method APHA 2540 D, using samples of similar concentration.

Figure 9. MU for Total Suspended Solids testing of sample PTA 1, as reported by participants, compared with 95% confidence interval for overall reproducibility, ± 8.71 mg/L in this round, shown as a dashed line.

0

1

2

3

4

5

6

7

8

9

0 1.5 3 4.5 6 7.5 9 10.5 12 13.5 15 16.5 18 19.5

Fre

quen

cy


Total Suspended Solids ± MU - Sample PTA 1

APHA 2540 D

Other

14

SD 9.17.08

Figure 10. MU for Total Suspended Solids testing of sample PTA 2, as reported by participants, compared with 95% confidence interval for overall reproducibility, ± 11.05 mg/L in this round, shown as a dashed line.

0

2

4

6

8

10

12

0 3 6 9 12 15 18 21 24 27 30 33 36 39

Fre

quen

cy


Total Suspended Solids ± MU - Sample PTA 2

APHA 2540 D

Other

15

SD

9.17.08

Results of sam

ple PT

A 1, including M

U, com

pared to the m

edian

Total S

uspended Solids - S

ample P

TA

1

Figure 11. Total Suspended Solids - Results of sample PTA 1, including MU, compared to the median. Theoutlier result of laboratory 607 is not shown.

40

50

60

70

80

9012

0

126

128

138

183

196

210

235

237

271

274

286

300

310

329

334

350

375

382

390

398

410

412

466

471

498

499

514

519

526

545

551

563

568

588

629

633

634

660

674

Re

sults

(mg/

L)

Laboratory Code



16

SD

9.17.08

Results of sam

ple PT

A 2, including M

U, com

pared to the m

edian

Total S

uspended Solids - S

ample P

TA

2

Figure 12. Total Suspended Solids - Results of sample PTA 2, including MU, compared to the median. Theoutlier result of laboratory 551 is not shown.

50

60

70

80

90

100

110

12012

0

126

128

138

183

196

210

235

237

271

274

286

300

310

329

334

350

375

382

390

398

410

412

466

471

498

499

514

519

526

545

563

568

588

607

629

633

634

660

674

Re

sults

(mg/

L)

Laboratory Code



17

SD 9.17.08

4.2.3 Total Dissolved Solids Table 4 compares the Total Dissolved Solids median and robust CV from this round to those obtained in previous PTA rounds. Table 4. Comparison of current round variability and proficiency median of Total Dissolved Solids testing with the results of the previous two rounds.



PTA 2 356.0 6.3 48

Report 830 PTA 1 304.0 7.2 55

PTA 2 220.0 8.4 55

Report 767 PTA 1 199.0 6.2 58

PTA 2 231.0 5.9 58 Bias / Accuracy The Total Dissolved Solids testing was successfully performed, with satisfactory results (|z-score| ≤ 2.0) ranging between 182 – 234 mg/L for sample PTA 1 and 312 – 400 mg/L for sample PTA 2. Out of 48 participants, three questionable results (2.0 < |z-score| < 3.0) were reported for sample PTA 1 (laboratories 323a, 514 and 575) and three questionable results were reported for sample PTA 2 (laboratories 412, 464 and 553). Four outlier results (|z-score| ≥ 3.0) were obtained for sample PTA 1, requiring follow-up action by laboratories 117, 362b, 412 and 499. Two outlier results were obtained for sample PTA 2, requiring follow-up action by laboratories 362b and 499. The Total Dissolved Solids data set formed an approximately normal distribution with no substantial bias attributable to any one method (Figures 13 and 14). The method APHA 2540 C (Total Dissolved Solids Dried at 180ºC - method code 8) was the most popular method choice for Total Dissolved Solids analysis, being used by approximately 88% of participants for sample PTA 1 and 85% of participants for sample PTA 2. As expected, laboratories which tended to low bias on their Total Suspended Solids results, high biased on their Total Dissolved Solids results, as their filters retained a smaller proportion of suspended solids, consequently overestimating the amount of dissolved solids in the sample.

18

SD 9.17.08

Figure 13. Spread of results for Total Dissolved Solids testing of sample PTA 1, with a median of 208.0 mg/L.

Figure 14. Spread of results for Total Dissolved Solids testing of sample PTA 2, with a median of 356.0 mg/L.

0

4

8

12

16

20

160 170 180 190 200 210 220 230 240 250 260 270 280 290

Fre

quen

cy

Results (mg/L)

Total Dissolved Solids - Sample PTA 1

APHA 2540 C

Calculation

Other

0

2

4

6

8

10

12

14

16

270 290 310 330 350 370 390 410 430 450 470 490 510 530

Fre

quen

cy

Results (mg/L)


APHA 2540 C

US EPA 0160.1

Calculation

Other

19

SD 9.17.08

Measurement Uncertainty (MU) The MU reported by participants can be seen in Figures 15 and 16. Out of 48 participants, 36 (75%) submitted MU information. Many of the stated MUs did not accurately reflect the difference between the median and the participant’s result for these proficiency samples. Laboratories 138, 382, 412, 471, 499, 545, 551 and 607 may wish to re-examine their MU calculations, as their result was further from the median than their stated MU at least for one of the samples tested, as shown in Figures 17 and 18 below. A t-test of all the results (outliers removed), indicated that the overall reproducibility for Total Dissolved Solids testing was 208.0 ± 28.0 mg/L (13%) for sample PTA 1 and 356.0 ± 46.4 (13%) mg/L for sample PTA 2 (95% CI). This was very close to the expected precision stated in APHA 2540 C.

Figure 15. MU for Total Dissolved Solids testing of sample PTA 1, as reported by participants, compared with 95% confidence interval for overall reproducibility, ± 28.0 mg/L in this round, shown as a dashed line.

0

2

4

6

8

10

12

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Fre

quen

cy


Total Dissolved Solids ± MU - Sample PTA 1

APHA 2540 C

Calculation

Other

20

SD 9.17.08

Figure 16. MU for Total Dissolved Solids testing of sample PTA 2, as reported by participants, compared with 95% confidence interval for overall reproducibility, ± 46.4 mg/L in this round, shown as a dashed line.

0

1

2

3

4

5

6

7

8

9

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Fre

quen

cy


Total Dissolved Solids ± MU - Sample PTA 2

APHA 2540 C

Calculation

Other

21

SD

9.17.08

Results of sam

ple PT

A 1, including M

U, com

pared to the m

edian

Total D

issolved Solids - S

ample P

TA

1

Figure 17. Total Dissolved Solids - Results of sample PTA 1, including MU, compared to the median.

100

150

200

250

30012

6

128

138

183

196

210

237

271

274

286

310

329

334

350

375

382

390

398

410

412

466

471

499

514

519

526

545

551

563

568

588

607

616

633

634

660

Re

sults

(mg/

L)

Laboratory Code



22

SD

9.17.08

Results of sam

ple PT

A 2, including M

U, com

pared to the m

edian

Total D

issolved Solids - S

ample P

TA

2

Figure 18. Total Dissolved Solids - Results of sample PTA 2, including MU, compared to the median.

200

250

300

350

400

45012

6

128

138

183

196

210

237

271

274

286

310

329

334

350

375

382

390

398

410

412

466

471

499

514

519

526

545

551

563

568

588

607

616

633

634

660

Re

sults

(mg/

L)

Laboratory Code



23

SD 9.17.08

4.3 Analysis of Results by Method Groups

Further analysis of results by method groups was undertaken to provide specific information on individual method performance. In order for methods to be grouped for analysis, PTA requires at least 11 sets of results from the same method group. For methods other than those presented below, there were less than 11 results submitted for each method, therefore reliable conclusions cannot be drawn from analysing them separately on this occasion.

4.3.1. Total Solids

The method APHA 2540 B (Total Solids Dried at 103-105ºC - method code 1) was most frequently employed for Total Solids analysis. Out of 41 participants for sample PTA 1 and 42 participants for sample PTA 2, 33 laboratories (80% and 79%, respectively) indicated the use of this method. Table 5 below presents the median, uncertainty of the median and robust CV for Total Solids results obtained by this method in round 172. Table 5. Variability and proficiency medians of Total Solids results obtained by method APHA 2540 B.

Analyte Sample Participants Median ±

Uncertainty of the Median (mg/L)

Robust CV (%)

Total Solids PTA 1 33 275.0 ± 3.6 5.9

PTA 2 33 437.0 ± 2.4 2.5

4.3.2. Total Suspended Solids

The method APHA 2540 D (Total Suspended Solids Dried at 103-105ºC - method code 5) was most frequently employed for Total Suspended Solids analysis. Out of 54 participants for sample PTA 1 and 55 participants for sample PTA 2, 52 (96%) and 53 (96%) laboratories indicated the use of this method, respectively. Table 6 below presents the median, uncertainty of the median and robust CV for Total Suspended Solids results obtained by this method in round 172. Table 6. Variability and proficiency medians of Total Suspended Solids results obtained by method APHA 2540 D.



Robust CV (%)

Total Suspended Solids

PTA 1 52 66.00 ± 0.67 5.8

PTA 2 53 82.00 ± 0.89 6.3

24

SD 9.17.08

4.3.3. Total Dissolved Solids

The method APHA 2540 C (Total Dissolved Solids Dried at 180ºC - method code 8) was most frequently employed for Total Dissolved Solids analysis. Out of 48 participants, 42 (88%) and 41 (85%) indicated the use of this method for samples PTA 1 and PTA 2, respectively. Table 7 below presents the median, uncertainty of the median and robust CV for Total Suspended Solids results obtained by this method in round 172. Table 7. Variability and proficiency medians of Total Dissolved Solids results obtained by method APHA 2540 C.



Robust CV (%)


PTA 1 42 207.5 ± 2.5 6.3

PTA 2 41 355.0 ± 4.9 7.1

25

SD 9.17.08

5. Outlier Results

Laboratories reporting results that have been identified as outliers are listed in Table 8 below. Table 8. Laboratory results identified as outliers for each analysis performed.

Lab Code

Analysis

Total Solids Total Suspended Solids

Total Dissolved Solids

PTA 1 PTA 2 PTA 1 PTA 2 PTA 1 PTA 2

117 §

310 §

323a § §

362b § § § §

412 §

464 §

498 §

499 § §

517 §

551 §

563 §

590 § §

607 § §

Note: 1. A “§” indicates the occurrence of a z-score outlier result (i.e. those results for which

|z-score| ≥ 3.0).

6. Reference

[1] Guide to Proficiency Testing Australia, 2014 (This document can be found on the PTA website, www.pta.asn.au)

SD 9.17.08

APPENDIX A

Results and Data Analysis Total Solids ............................................................................................................................ A1

Total Suspended Solids ........................................................................................................ A7

Total Dissolved Solids ......................................................................................................... A13

SD 9.17.08

Total Solids Results

Samples PTA 1 and PTA 2

A1

SD 9.17.08

Total Solids

Results by Laboratory Code

Lab Code

Sample PTA 1

Result ± MU1 (mg/L)

Robust z-score2

Method Code3

117 300 # 1.47 1 120 278 # 0.18 1 126 275 ± 18 0.00 1 128 298 ± 30 1.35 1 138 298 ± 25 1.35 3 183 278 ± 20 0.18 1 196 272 ± 2 -0.18 1 210 252 ± 30 -1.35 1 237 285 ± 19.38 0.59 1 271 275 ± 25 0.00 3 274 264 ± 8.12 -0.65 3 286 270 ± 40.5 -0.29 1 310 300 ± 42 1.47 1

323a 291 # 0.94 1 329 280 ± 34 0.29 1 342 265 # -0.59 1 350 294 ± 16 1.11 1

362b 351 # 4.46 § 3 382 286 ± 1 0.65 1 390 273 ± 28.39 -0.12 1 398 263 ± 53 -0.70 1 410 275 ± 30 0.00 1 464 254 # -1.23 1 466 277 ± 18 0.12 4 471 291 ± 13 0.94 1 498 370 ± 81 5.57 § 1 506 269 # -0.35 1 519 283 ± 9.759 0.47 1 545 258 ± 8 -1.00 1 551 267.4 ± 5 -0.45 3 553 280 # 0.29 1 563 344 ± 20 4.05 § 1

1 Where reported, results are shown with their corresponding

measurement uncertainty (MU). 2 "§" denotes an outlier (i.e. those results for which |z-score| ≥ 3.0).

Robust z-scores are calculated as: z = (A - median) ÷ normalised IQR, where A is the participant laboratory's result.

3 Please refer to Appendix C (page C3) for method code descriptions.

A2

SD 9.17.08

Total Solids - cont.


Lab Code

Sample PTA 1


Robust z-score2

Method Code3

568 270 ± 41 -0.29 3 575 240 # -2.05 1 588 268 ± 27 -0.41 1 590 272 # -0.18 1 596 270 # -0.29 1 607 224 ± 1 -2.99 3 633 292 ± 58 1.00 1 634 265 ± 10 -0.59 1 660 269 ± 70 -0.35 1

No of Results: 41

Median: 275.0 Normalised

IQR: 17.0

Uncertainty of the Median:

3.3

Robust CV: 6.2%

Minimum: 224

Maximum: 370

Range: 146 1 Where reported, results are shown with their corresponding

measurement uncertainty (MU).

2 "§" denotes an outlier (i.e. those results for which |z-score| ≥ 3.0). Robust z-scores are calculated as: z = (A - median) ÷ normalised IQR, where A is the participant laboratory's result.


SD 9.17.08

Total Solids - Sample PTA 1 - Robust Z-Scores

Ordered R

obust Z-S

core Charts

Total S

olids - Sam

ple PT

A 1

A3

Robust Z-Scores

607

575 21

0

464

545 39

8

274

342

634

551

588

506

660

286

568

596

196

590

390

126

-5

-4

-3

-2

-1

0

1

2

3

4

5z-

scor

e

lab code

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

A4

SD 9.17.08

Total Solids


Lab Code

Sample PTA 2


Robust z-score2

Method Code3

117 420 # -0.86 1 120 435 # 0.00 1 126 440 ± 20 0.29 1 128 468 ± 47 1.89 1 138 461 ± 38 1.49 3 183 438 ± 20 0.17 1 196 438 ± 2 0.17 1 210 389 ± 45 -2.64 1 237 439 ± 45.6 0.23 1 271 447 ± 25 0.69 3 274 426 ± 13.1 -0.52 3 286 430 ± 64.5 -0.29 1 310 490 ± 69 3.16 § 1

323a 445 # 0.57 1 329 453 ± 54 1.03 1 342 435 # 0.00 1 350 451 ± 24 0.92 1

362a 430 # -0.29 3 362b 563 # 7.35 § 3 382 454 ± 1 1.09 1 390 429 ± 44.62 -0.34 1 398 416 ± 83 -1.09 1 410 430 ± 40 -0.29 1 464 369 # -3.79 § 1 466 413 ± 28 -1.26 4 471 455 ± 13 1.15 1 498 452 ± 28 0.98 1 506 431 # -0.23 1 519 441 ± 7.864 0.34 1 545 435 ± 8 0.00 1 551 387 ± 5 -2.76 3 553 422 # -0.75 1





A5

SD 9.17.08

Total Solids - cont.


Lab Code

Sample PTA 2


Robust z-score2

Method Code3

563 474 ± 20 2.24 1 568 419 ± 52 -0.92 3 575 400 # -2.01 1 588 440 ± 44 0.29 1 590 437 # 0.11 1 596 410 # -1.44 1 607 366 ± 0.1 -3.96 § 3 633 438 ± 88 0.17 1 634 430 ± 10 -0.29 1 660 435 ± 70 0.00 1

No of Results: 42


IQR: 17.4


3.4

Robust CV: 4.0%

Minimum: 366

Maximum: 563





SD 9.17.08

Total Solids - Sample PTA 2 - Robust Z-Scores

Ordered R

obust Z-S

core Charts

Total S

olids - Sam

ple PT

A 2

A6

Robust Z-Scores

607

464

551

210 57

5 596

466

398

568

117

553

274

390

286

362a 41

0

634

506

120

342

545

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

SD 9.17.08

Total Suspended Solids Results


A7

SD 9.17.08



Lab Code

Sample PTA 1


Robust z-score2

Method Code3

117 75 # 2.23 5 120 72.2 ± 7 1.53 5 123 66.0 # 0.00 5 126 64.0 ± 5 -0.50 5 128 70.6 ± 7.1 1.14 5 138 67.5 ± 5.6 0.37 5 183 63.8 ± 5 -0.54 5 196 67.0 ± 1 0.25 5 210 65 ± 15 -0.25 5 235 67.0 ± 5 0.25 5 237 54.9 ± 2.52 -2.75 5 271 70.3 ± 4.4 1.06 7 274 65.0 ± 2.98 -0.25 5 286 70 ± 10.5 0.99 5 300 67 ± 13.86 0.25 5 310 70.0 ± 5.2 0.99 5

323a 52.4 # -3.37 § 5 329 57.0 ± 6.3 -2.23 5 334 71.4 ± 2.1 1.34 5 342 56.8 # -2.28 5 350 71.2 ± 6.2 1.29 5

362b 64 # -0.50 5 375 65.5 ± 3.3 -0.12 5 382 69 ± 1 0.74 5 390 68.6 ± 8.644 0.64 5 398 64.0 ± 12.8 -0.50 5 410 75 ± 10 2.23 5 412 64 ± 5.0 -0.50 5 464 63 # -0.74 5 466 74 ± 5 1.98 5 471 65.1 ± 1.7 -0.22 5 474 66.5 # 0.12 5





A8

SD 9.17.08

Total Suspended Solids - cont.


Lab Code

Sample PTA 1


Robust z-score2

Method Code3

498 64 ± 2 -0.50 5 499 63.3 ± 1.9 -0.67 5 506 64.0 # -0.50 7 514 64.0 ± 7.6 -0.50 5 517 69.6 # 0.89 5 519 68.1 ± 0.66 0.52 5 526 67.3 ± 10 0.32 5 545 65.9 ± 3.0 -0.02 5 551 61.4 ± 0.50 -1.14 5 553 63.0 # -0.74 5 563 70.0 ± 5 0.99 5 568 66.5 ± 13 0.12 5 575 60 # -1.49 5 588 70 ± 4 0.99 5 590 50.5 # -3.84 § 5 596 68.0 # 0.50 5 607 33.33 ± 14.53 -8.09 § 5 629 66 ± 9.9 0.00 5 633 69.0 ± 13 0.74 5 634 60.6 ± 12 -1.34 5 660 66.0 ± 10 0.00 5 674 72.0 ± 2.0 1.49 5

No of Results: 54


IQR: 4.04


0.69

Robust CV: 6.1%

Minimum: 33.33

Maximum: 75

Range: 41.67 1 Where reported, results are shown with their corresponding




SD 9.17.08

Total Suspended Solids - Sample PTA 1 - Robust Z-Sc ores

Ordered R

obust Z-S

core Charts

Total S

uspended Solids - S

ample P

TA

1

A9

Robust Z-Scores

607

590

323a

237 34

2

329 57

5

634

551 46

4

553

499

183

126

362b 39

8

412

498

506

514

210

274

471

375

545

123

629

-5

-4

-3

-2

-1

0

1

2

3

4

5z-

scor

e

lab code

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

A10

SD 9.17.08



Lab Code

Sample PTA 2


Robust z-score2

Method Code3

117 85 # 0.58 5 120 90.7 ± 9 1.68 5 123 73 # -1.73 5 126 80.0 ± 6 -0.39 5 128 87.4 ± 8.7 1.04 5 138 82.5 ± 6.8 0.10 5 183 77.5 ± 5 -0.87 5 196 81.0 ± 1 -0.19 5 210 86 ± 20 0.77 5 235 82.4 ± 6 0.08 5 237 78.5 ± 6.35 -0.67 5 271 96.9 ± 4.4 2.87 7 274 80.5 ± 3.69 -0.29 5 286 86 ± 12.9 0.77 5 300 86 ± 17.67 0.77 5 310 90.0 ± 6.7 1.54 5

323a 63.1 # -3.64 § 5 329 78.0 ± 8.6 -0.77 5 334 87.6 ± 2.5 1.08 5 342 80.2 # -0.35 5 350 85.4 ± 7.5 0.66 5

362a 78.0 # -0.77 5 362b 79 # -0.58 5 375 83.0 ± 4.2 0.19 5 382 84 ± 1 0.39 5 390 87.8 ± 11.06 1.12 5 398 78.5 ± 15.7 -0.67 5 410 95 ± 10 2.51 5 412 82 ± 5.8 0.00 5 464 79 # -0.58 5 466 93 ± 5 2.12 5 471 81.9 ± 1.7 -0.02 5





A11

SD 9.17.08

Total Suspended Solids - cont.


Lab Code

Sample PTA 2


Robust z-score2

Method Code3

474 85.5 # 0.67 5 498 82 ± 4 0.00 5 499 80.3 ± 2.4 -0.33 5 506 74.3 # -1.48 7 514 81.4 ± 7.6 -0.12 5 517 97.8 # 3.04 § 5 519 79.3 ± 1.53 -0.52 5 526 84.0 ± 10 0.39 5 545 79.6 ± 3.0 -0.46 5 551 21.4 ± 0.50 -11.68 § 5 553 71.0 # -2.12 5 563 87.0 ± 5 0.96 5 568 82.0 ± 16 0.00 5 575 90 # 1.54 5 588 88 ± 6 1.16 5 590 61.0 # -4.05 § 5 596 71.0 # -2.12 5 607 82.3 ± 26.01 0.06 5 629 82 ± 12.3 0.00 5 633 84.0 ± 17 0.39 5 634 76.2 ± 12 -1.12 5 660 82.0 ± 10 0.00 5 674 89.0 ± 2.5 1.35 5

No of Results: 55


IQR: 5.19


0.88

Robust CV: 6.3%

Minimum: 21.4

Maximum: 97.8

Range: 76.4 1 Where reported, results are shown with their corresponding




SD 9.17.08

Total Suspended Solids - Sample PTA 2 - Robust Z-Sc ores

Ordered R

obust Z-S

core Charts

Total S

uspended Solids - S

ample P

TA

2

A12

Robust Z-Scores

551

590

323a

553

596 12

3

506 63

4

183

329

362a 23

7

398

362b 46

4

519

545

126

342

499

274

196

514

471

412

498

568

629

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

SD 9.17.08

Total Dissolved Solids Results


A13

SD 9.17.08



Lab Code

Sample PTA 1


Robust z-score2

Method Code3

117 250 # 3.19 § 8 120 201 # -0.53 8 123 220 # 0.91 8 126 221 ± 16 0.99 8 128 226 ± 23 1.37 8 138 230 ± 19 1.67 8 183 216 ± 20 0.61 8 196 206 ± 1 -0.15 8 210 184 ± 25 -1.82 8 237 233 ± 23.7 1.90 8 271 205 ± 25 -0.23 11 274 199 ± 7.55 -0.68 8 286 203.0 ± 30.4 -0.38 8 310 230 ± 32 1.67 8

323a 238 # 2.28 8 329 220 ± 22 0.91 8 334 207 ± 9.7 -0.08 8 342 208 # 0.00 8 350 208 ± 17 0.00 8

362b 287 # 6.00 § 11 375 221 ± 11 0.99 11 382 212 ± 1 0.30 8 390 204 ± 14.280 -0.30 8 398 210 ± 42 0.15 8 410 200 ± 20 -0.61 8 412 262 ± 8.8% 4.10 § 8 464 191 # -1.29 8 466 205 ± 14 -0.23 8 471 227 ± 10 1.44 8 499 257 ± 3 3.72 § 11 506 197 # -0.84 8 514 181 ± 41.4 -2.05 8





A14

SD 9.17.08

Total Dissolved Solids - cont.


Lab Code

Sample PTA 1


Robust z-score2

Method Code3

519 211 ± 9.610 0.23 8 526 204 ± 50 -0.30 8 545 231 ± 8 1.75 8 551 206 ± 5.0 -0.15 8 553 184 # -1.82 8 563 209 ± 23 0.08 8 568 203 ± 31 -0.38 8 575 180 # -2.13 8 588 204 ± 22 -0.30 8 590 221 # 0.99 8 596 200 # -0.61 8 607 223 ± 0.7 1.14 11 616 204 ± 11 -0.30 8 633 208 ± 42 0.00 8 634 204 ± 10 -0.30 10 660 205 ± 90 -0.23 8

No of Results: 48


IQR: 13.2


2.4

Robust CV: 6.3%

Minimum: 180

Maximum: 287





SD 9.17.08

Total Dissolved Solids - Sample PTA 1 - Robust Z-Sc ores

Ordered R

obust Z-S

core Charts

Total D

issolved Solids - S

ample P

TA

1

A15

Robust Z-Scores

575

514

210

553 46

4 506

274

410

596

120

286

568

390

526

588

616

634

271

466

660

196

551

334

342

-5

-4

-3

-2

-1

0

1

2

3

4

5z-

scor

e

lab code

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

A16

SD 9.17.08



Lab Code

Sample PTA 2


Robust z-score2

Method Code3

117 350 # -0.27 8 120 351 # -0.22 8 126 363 ± 20 0.31 8 128 376 ± 38 0.89 8 138 378 ± 31 0.98 8 183 357 ± 20 0.04 8 196 359 ± 1 0.13 8 210 330 ± 40 -1.16 8 237 371 ± 20.8 0.67 8 271 350 ± 25 -0.27 11 274 345 ± 12.6 -0.49 8 286 345.5 ± 51.8 -0.47 8 310 370 ± 52 0.62 8

323a 381 # 1.11 8 329 375 ± 38 0.85 8 334 364 ± 16.7 0.36 8 342 355 # -0.04 8 350 362 ± 29 0.27 8

362a 352 # -0.18 9 362b 484 # 5.71 § 11 375 372 ± 19 0.71 11 382 336 ± 1 -0.89 8 390 364 ± 25.48 0.36 8 398 347 ± 69 -0.40 8 410 335 ± 30 -0.94 8 412 404 ± 8.8% 2.14 8 464 290 # -2.94 8 466 330 ± 22 -1.16 8 471 371 ± 10 0.67 8 499 434 ± 4 3.48 § 11 506 350 # -0.27 8 514 326 ± 41.4 -1.34 8





A17

SD 9.17.08

Total Dissolved Solids - cont.


Lab Code

Sample PTA 2


Robust z-score2

Method Code3

519 358 ± 10.990 0.09 8 526 320 ± 50 -1.61 8 545 395 ± 8 1.74 8 551 366 ± 5.0 0.45 8 553 420 # 2.85 8 563 342 ± 23 -0.62 8 568 337 ± 44 -0.85 8 575 330 # -1.16 8 588 346 ± 38 -0.45 8 590 376 # 0.89 8 596 330 # -1.16 8 607 366 ± 0.5 0.45 11 616 363 ± 20 0.31 8 633 328 ± 66 -1.25 8 634 354 ± 10 -0.09 10 660 336 ± 90 -0.89 8

No of Results: 48


IQR: 22.4


4.1

Robust CV: 6.3%

Minimum: 290

Maximum: 484





SD 9.17.08

Total Dissolved Solids - Sample PTA 2 - Robust Z-Sc ores

Ordered R

obust Z-S

core Charts

Total D

issolved Solids - S

ample P

TA

2

A18

Robust Z-Scores

464

526

514

633

210

466

575

596

410

382

660

568

563

274

286

588

398

117

271

506

120

362a 63

4

342

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

-5

-4

-3

-2

-1

0

1

2

3

4

5

z-sc

ore

lab code

SD 9.17.08

APPENDIX B

Sample Homogeneity and Stability

Homogeneity and Stability Testing ........................................................................................ B1

B1

SD 9.17.08

Homogeneity and Stability Testing Samples for this program were obtained from Global Proficiency Ltd, New Zealand. As such, all samples are subjected to rigorous stability and homogeneity testing. A random selection of ten samples was chosen from samples PTA 2 for homogeneity and stability testing. Seven of these were stored chilled and the remaining three were subjected to 35ºC for three days for an accelerated ageing stability trial. The samples were then analysed by Hill Laboratories, New Zealand. All stability samples showed no increased variability when compared to the chilled samples. Samples PTA 1 were also tested to confirm the levels were within the expected range. Three samples were randomly selected, stored chilled in the same conditions as the homogeneity samples and subjected to a verification testing (one replicate per sample) by Hill Laboratories, New Zealand. Homogeneity and stability characteristics were assumed to be similar to samples PTA 2, based on identical manufacturing procedure and sample handling. From statistical analyses based on the results of this testing and rigorous quality control, it was considered that all samples were sufficiently homogeneous and stable, so that any results later identified as outliers should not be attributed to any notable sample variability. The results of homogeneity and stability testing are presented in Tables B1 and B2 below. Please note that the mean results for these tests are not intended to be used as reference values. Table B1. Homogeneity and stability testing of PTA 2 samples.

Round PTA 172

Samples PTA 2 (g/m 3)

Sample ID Total Suspended Solids Total Dissolved Solids Total Solids

Homogeneity H1 76.0 ± 11 344 ± 42 435 ± 70 H2 81.0 ± 12 386 ± 47 413 ± 67 H3 79.0 ± 12 354 ± 43 432 ± 70 H4 81.0 ± 12 359 ± 44 426 ± 69 H5 79.0 ± 12 355 ± 44 431 ± 70 H6 77.0 ± 11 369 ± 45 429 ± 69 H7 77.0 ± 11 364 ± 45 424 ± 70

Stability S1 81.0 ± 12 360 ± 44 414 ± 67 S2 81.0 ± 12 359 ± 44 428 ± 69 S3 81.0 ± 12 357 ± 44 411 ± 66

RSD 2.53% 3.06% 2.03% Table B2. Confirmatory testing of PTA 1 samples.

Round PTA 172

Samples PTA 1 (g/m 3)

Sample ID Total Suspended Solids Total Dissolved Solids Total Solids

Homogeneity H1 57.7 ± 8.4 219 ± 28 266 ± 44 H2 63.7 ± 9.2 208 ± 26 262 ± 43 H3 61.0 ± 8.8 214 ± 27 258 ± 42

SD 9.17.08

APPENDIX C

Documentation

Instructions to Participants .................................................................................................... C1

Method Codes ....................................................................................................................... C3

Results Sheet ........................................................................................................................ C4

SD 9.17.08

CHEMICAL ANALYSIS ROUND 172 Total Solids (TS), Total Suspended Solids (TSS), Total Dissolved Solids (TDS)

**Please record (on the Results Sheet) the approximate

Please note the following before commencing the analysis of the samples. 1. Samples

i)

ii)

iii)

Please Note:laboratory sample.

2. Sample Preparation

Note:

Caution:

i)

ii)

iii)

iv)

v)

vi)

vii)

viii)

Please report results for the

SD 9.17.08

CHEMICAL ANALYSIS ROUND 172

Total Solids (TS), Total Suspended Solids (TSS), Total Dissolved Solids (TDS)


Please note the following before commencing the analysis of the samples.

Samples

Two plastic vials labelled PTA 1 and PTA 2, supplied by Global Proficiency Ltd. The vials contain 20 mL of artificial waste watesuspended solids and total dissolved solids

Each vial will require dilution in reagent grade water. Please follow the Sample Preparation section below.

The vials must be thoroughly mixed prior to analysis

Please Note: laboratory sample.

Sample Preparation

Note: The Residue sample colour is white.

Caution: Analysis must begin immediately after vial is opened.

A separate sample mus

Adjust vial temperature to 20ºC.

Add approximately 800 mL of reagent grade water to a one

Record vial ID number and mix thoroughly.

Quantitatively transfer the entire contents from the vial into the flavial with reagent grade water and include this in the flask.

Bring to volume with reagent grade water.

Close the flask with a stopper and mix by inversion.

viii) Repeat steps ii)

Please report results for the

PROFICIENCY TESTING AUSTRALIA

WATERS PROFICIENCY TESTING PROGRAM



INSTRUCTIONS TO PARTICIPANTS




Each vial will require dilution in reagent grade water. Please follow the Sample Preparation section below.


Where possible, proficiency testing samples should be treated as a routine laboratory sample.

Sample Preparation

The Residue sample colour is white.

Analysis must begin immediately after vial is opened.

A separate sample mus







Repeat steps ii) – vii) for second sample.

Please report results for the diluted sample.


ERS PROFICIENCY TESTING PROGRAM







Each vial will require dilution in reagent grade water. Please follow the Sample Preparation


Where possible, proficiency testing samples should be treated as a routine



A separate sample must be prepared from each vial.







vii) for second sample.

diluted sample.

C1





**Please record (on the Results Sheet) the approximatereceipt**


Two plastic vials labelled PTA 1 and PTA 2, supplied by Global Proficiency Ltd. The vials contain 20 mL of artificial waste water concentrates for analysis of total solids, total suspended solids and total dissolved solids






t be prepared from each vial.






vii) for second sample.

diluted sample.





**Please record (on the Results Sheet) the approximate temperature of the samples upon


Two plastic vials labelled PTA 1 and PTA 2, supplied by Global Proficiency Ltd. The vials r concentrates for analysis of total solids, total





t be prepared from each vial.

Add approximately 800 mL of reagent grade water to a one-







temperature of the samples upon





-litre volumetric flask.

Quantitatively transfer the entire contents from the vial into the flask, rinse the sides of the

OCTOBER, 2014






litre volumetric flask.

sk, rinse the sides of the

OCTOBER, 2014





sk, rinse the sides of the

C2

SD 9.17.08

3. Tests Requested

For the samples prepared from the two vials PTA 1 and PTA 2: i) Total Solids (TS).

ii) Total Suspended Solids (TSS).

iii) Total Dissolved Solids (TDS).

(It is recommended that a reagent water blank is analysed by the same method used to analyse the samples.) If unable to perform the above please note this on your Results Sheet.

4. Safety

i) Samples are for laboratory use only.

ii) Participants should have sufficient experience and training to take the necessary precautions when handling the samples and reagent chemicals and during disposal.

iii) Use of safety glasses, gloves, and fume hoods, where appropriate during the determinations, is recommended.

5. Reporting

i) Report results using:

Total Solids zero decimal places Total Suspended Solids one decimal place

Total Dissolved Solids zero decimal places

ii) Report results in milligrams per litre (mg/L).

iii) Do not correct results for recovery.

iv) In addition to reporting the results, record the method of analysis using the attached codes.

v) Laboratories are also requested to calculate and report an estimate of measurement uncertainty (MU) for each reported measurement result. All estimates of MU must be given as a 95% confidence interval (coverage factor k ≈ 2) and reported in mg/L.

6. Testing should commence as soon as possible after receiving the samples and results reported

NO LATER THAN 14 NOVEMBER 2014 to:

Delfina Mihaila Proficiency Testing Australia PO Box 7507 SILVERWATER NSW 2128 AUSTRALIA Phone: +612 9736 8397 Fax: +612 9743 6664 Email: [email protected]

7. For this program your laboratory has been allocated the code number shown on the attached

Results Sheet. All reference to your laboratory in reports associated with the program will be through this code number, thus ensuring the confidentiality of your results.

8. As a guide, ranges for the samples can be expected to be (in mg/L):

Analyte Range Total Solids 140 – 675 mg/L Total Suspended Solids 23 – 100 mg/L Total Dissolved Solids 140 – 650 mg/L

C3

SD 9.17.08

Method Codes to be used for the Results Sheet

ANALYSIS METHOD REFERENCE METHOD DESCRIPTION CODE

Total Solids

Dried at 103–105°C

APHA SM

2540 B. Total Solids Dried at 103–105°C 1

US EPA 0160.3 Residue, Total 2

Other

Calculation: Suspended + Dissolved 3

Other (please specify) 4


Dried at 103–105°C

APHA SM

2540 D. Total Suspended Solids Dried at 103–105°C 5

US EPA 0160.2 Residue, Non-Filterable & Total Suspended Solids 6

Other



Dried at 180°C

APHA SM

2540 C. Total Dissolved Solids Dried at 180°C 8

US EPA 0160.1 Residue, Filterable 9

Other

Calculation: Total – Suspended 10


Method Reference Key i) APHA SM APHA “Standard Methods for the Examination of Water and Wastewater” (18,

19, 20, 21 and 22 Edition).

ii) USEPA U.S Environmental Protection Agency, http://www.epa.gov/osa/fem/methcollectns.htm.

SD 9.17.08

*Approximate temperature o

Total Solids

Dried at 103Total Suspended Solids

Dried at 103Total Dissolved Solids

Dried at 180°C

Please state: Please note:

i) For ii) Report results iii) Report results in iv) Do not correct results for recovery.v) MU* Laboratories Measurem

mg/L DATE:

INSTRUCT WAT SD 9.17.08


*Approximate temperature o

ANALYSIS

Total Solids

Dried at 103 –105°CTotal Suspended Solids

Dried at 103 –105°CTotal Dissolved Solids

Dried at 180°C

Please state: Brand of filter used

Nominal Filter size

Please note: Where possible, proficiency testing samples should be treated as a routine laboratory sample.

For each sample only a single result is requested.Report results Total Solids Total Suspended Solids Total Dissolved SolidsReport results in Do not correct results for recovery.MU* Laboratories Measuremmg/L.

DATE: ______________________

Return results Delfina MihailaProficiency Testing AustraliaPO Box 7507 SILVERWATER NSW 2128 AUSTRALIA

INSTRUCT WATERS PROF TEST PROG 172

PROFI



*Approximate temperature of samples upon receipt:

ANALYSIS

105°C


105°C


Brand of filter used

Nominal Filter size

Where possible, proficiency testing samples should be treated as a routine laboratory sample.

sample only a single result is requested.Report results using:

Total Solids Total Suspended SolidsTotal Dissolved Solids

Report results in milligrams per litre (mg/L).Do not correct results for recovery.MU* Laboratories Measurem

______________________

Return results NO LATER THAN 14 NOVEMBER 2014 Delfina Mihaila Proficiency Testing AustraliaPO Box 7507 SILVERWATER NSW 2128 AUSTRALIA

ERS PROF TEST PROG 172




Total Solids (TS), Total Suspended Solids (TSS), Total Dissolved Solids (TDS)OCTOBER, 2014

RESULTS SHEET

f samples upon receipt:

SAMPLE PTA 1

Result (mg/L)

Brand of filter used

Nominal Filter size

Where possible, proficiency testing samples should be treated as a routine laboratory

sample only a single result is requested.

Total Suspended Solids Total Dissolved Solids

milligrams per litre (mg/L).Do not correct results for recovery. MU* Laboratories Measurement Uncertainty (MU) if known for the result. Please report in

______________________

NO LATER THAN 14 NOVEMBER 2014


SILVERWATER NSW 2128

ERS PROF TEST PROG 172

C4

CIENCY TESTING AUSTRALIA




RESULTS SHEET(mg/L)

f samples upon receipt:

SAMPLE PTA 1

±MU (mg/L)



zero decimal placesone decimal placezero decimal places.

milligrams per litre (mg/L).

ent Uncertainty (MU) if known for the result. Please report in

SIGNATURE:

NO LATER THAN 14 NOVEMBER 2014

Phone:SILVERWATER NSW 2128 Fax:

Email:





RESULTS SHEET

SAMPLE PTA 2

Result (mg/L)



zero decimal places one decimal place zero decimal places.


SIGNATURE: _______________________________

NO LATER THAN 14 NOVEMBER 2014 to:

Phone: +61 2 9736 8397 +61 2 9743 6664

Email: [email protected]





Laboratory Code

SAMPLE PTA 2

Result

±MU(mg/L)


zero decimal places.


_______________________________

to:

+61 2 9736 8397 +61 2 9743 6664 [email protected]


Laboratory Code

METHOD

CODE±MU (mg/L)



_______________________________

[email protected]

METHOD CODE



_______________________________

SD 9.17.08

- End of Report -

Report No Waters Proficiency Testing Round No. 172 Total...

Documents

Transcript of Report No Waters Proficiency Testing Round No. 172 Total...