Recreational and Surface Water Scheme - Gov.uk
Summary of Results External Quality Assessment of Water Microbiology
Recreational and Surface Water Scheme Distribution Number: S81
Sample Numbers: S81A, S81B
Distribution Date: Results Due: Report Date:
November 2017 08 December 2017 21 December 2017
Samples prepared and quality control tested by:
Angela Appea Richard Borrill Thomas Harper Zak Prior Judith Spellar Aneta Stranc Lili Tsegaye
Data analysed by:
Joanna Donn Nita Patel
Report compiled by:
Joanna Donn Nita Patel
Authorised by:
Nita Patel
This report must not be reproduced without permission of the organisers. Public Health England Food and Environmental Proficiency Testing Unit (FEPTU) 61 Colindale Avenue London NW9 5EQ Tel: +44 (0)20 8327 7119 Fax: +44 (0)20 8200 8264 Email: [email protected] The data in FEPTU reports is confidential
Page 1 of 18
Printed at 10:57 on Thursday, 21 December, 2017
For further information on the scheme please refer to: Scheme Guide: https://www.gov.uk/government/publications/food-and-water-proficiency-testing-schemes-scheme-guide Guide to Scoring and Statistics: https://www.gov.uk/government/publications/food-and-water-proficiency-testing-schemes-scoring-systems-and-statistics
General guidance for z-scores: Participants' enumeration results are converted into z-scores using the following formula:
Z = (xi-Xpt) σpt
xi Xpt
= participants' result expressed (expressed as a log 10 value) = assigned value (participants' consensus median (expressed as a log 10 value)
σpt
= the fixed standard deviation for the examination (calculated by FEPTU)
The σpt-value expresses the acceptable difference between the individual participant 's result and the participants' consensus median. The σpt-value used for calculating z-scores for all parameters in the Recreational and Surface Water Scheme is 0.35. A guide to interpreting z-scores follows, although laboratories must interpret their scores in the context of their own laboratory situation. z = -1.99 to +1.99 z = -2 to -2.99 or +2 to +2.99 z= < -3.00 or > + 3.00
satisfactory questionable unsatisfactory
It is usually recommended that z-scores exceeding +/-2 are investigated to establish the possible cause. general rule, PHE recommends that all questionable and unsatisfactory results are investigated.
As a
FEPTU Quality Control: To demonstrate homogeneity of the sample, a minimum of 10 LENTICULE® discs , selected randomly from a batch, are tested in duplicate for parameters requiring enumeration.
To demonstrate stability of the sample, a minimum of nine LENTICULE discs, selected randomly from a batch , are examined throughout the distribution period for enumeration parameters. PHE uses methods stipulated in the Microbiology of Recreational and Environmental Waters (2000) and the DWI’s series of documents: The Microbiology of Drinking Water (2002) - Methods for the Examination of Waters and Associated Materials. The FEPTU results are used for guidance in the preliminary intended results notification, letters are posted on the website immediately after every distribution; electronic notification of their availability is sent to all participants. Refer to section 17.0 of the Scheme Guide if you have experienced difficulties with any of the examinations . https://www.gov.uk/government/publications/food-and-water-proficiency-testing-schemes-scheme-guide
Participants are reminded that reporting an incorrect or false negative results for water samples could have serious public health implications. Participants who report unexpectedly high or low results for enumerations on single occasions only should not be unduly alarmed, although they should still assess the reason(s) for the outlying result.
Please contact FEPTU staff for advice and information: Repeat samples
Carmen Gomes or Kermin Daruwalla
Data Analysis
Manchari Rajkumar or Nita Patel
Microbiological advice
Nita Patel or Zak Prior
General comments and complaints
Nita Patel or Zak Prior
Scheme consultants
Julie E. Russell
Scheme Co-ordinator
Nita Patel
Tel: +44 (0)20 8327 7119 Fax: +44 (0)20 8200 8264 Email: [email protected] FEPTU's website
Accreditation: PHE Water EQA Scheme for Recreational and Surface Water is accredited by the United Kingdom Accreditation Service (UKAS) to ISO/IEC 17043:2010.
0006 The data in FEPTU reports is confidential
Page 2 of 18
Printed at 10:57 on Thursday, 21 December, 2017
Sample: S81A Water sample from river, lake and stream
Contents:
Enterobacter cloacae (wild strain), Enterococcus faecium (wild strain), Clostridium perfringens (wild strain), Salmonella Derby 1,4,[5],12:f,g:[1,2] (wild strain), Providencia rettgeri (NCTC 7475)
Expected Results: All counts are expressed as colony forming units (cfu) per 100mL. The fixed standard deviation value (σpt value) used for calculation of the z-scores is 0.35 for all parameters.
Parameter
FEPTU median
Coliform bacteria
Escherichia coli
Enterococci
Faecal coliforms
63
0
59
0
Clostridium perfringens
Salmonella spp.
75
Detected in
(1.88 log₁₀)
1L
No. results returned
68
77
71
34
58
45
Assigned value
72
0
63
0
87
N/A
(Participants
(1.94 log₁₀)
median all results) Uncertainty of
0.02
N/A
0.01
N/A
0.03
N/A
71
0
63
0
83
N/A
assigned value* Participants mean (all results)
(1.92 log₁₀)
Expected Range
23 - 228
N/A
20 - 199
N/A
28 - 2.75x10²
N/A
0.14
N/A
0.09
N/A
0.15
N/A
1
N/A
2
N/A
3
N/A
False positives
N/A
2
N/A
6
N/A
N/A
False negatives
1
N/A
1
N/A
1
0
Standard deviation** No of outlying counts
Your result
Score for performance assessment Z-score
*
U(Xpt) is based on results transformed to a log₁₀ scale
**
Robust S* based on median absolute deviation about the participants' median (MADe)
Total sent samples
85
Not examined
4
Non returns
2
Late returns
0
The data in FEPTU reports is confidential
Page 3 of 18
Printed at 10:57 on Thursday, 21 December, 2017
Sample: S81B Water sample from river, lake and stream
Contents:
Escherichia coli (wild strain), Klebsiella pneumoniae (wild strain), Enterococcus faecalis (wild strain), Clostridium perfringens (wild strain), Salmonella Stanley 1,4,[5],12,[27]:d:1,2 (wild strain)
Expected Results: All counts are expressed as colony forming units (cfu) per 100mL. The fixed standard deviation value (σpt value) used for calculation of the z-scores is 0.35 for all parameters.
Parameter
FEPTU median
Coliform bacteria
Escherichia coli
Enterococci
Faecal coliforms
Clostridium perfringens
Salmonella spp.
1.07x10²
93
81
1.01x10²
2.90x10²
Detected in
(2.03 log₁₀)
(1.97 log₁₀)
(1.91 log₁₀)
(2 log₁₀)
(2.46 log₁₀)
1L
68
77
71
35
58
45
1.65x10²
40
91
81
2.85x10²
N/A
(2.22 log₁₀)
(1.6 log₁₀)
(1.96 log₁₀)
(1.91 log₁₀)
(2.45 log₁₀)
0.03
0.1
0.01
0.1
0.04
N/A
1.58x10²
94
90
69
2.68x10²
N/A
(2.2 log₁₀)
(1.97 log₁₀)
(1.95 log₁₀)
(1.84 log₁₀)
(2.43 log₁₀)
52 - 5.22x10²
10 - 1.50x10²
29 - 2.88x10²
12 - 2.56x10²
90 - 9.00x10²
N/A
0.2
0.28
0.08
0.43
0.21
N/A
5
38
0
5
4
N/A
False positives
N/A
N/A
N/A
N/A
N/A
N/A
False negatives
0
35
0
0
1
2
No. results returned
Assigned value (Participants median all results) Uncertainty of assigned value* Participants mean (all results) Expected Range
Standard deviation** No of outlying counts
Your result
Score for performance assessment Z-score
*
U(Xpt) is based on results transformed to a log₁₀ scale
**
Robust S* based on median absolute deviation about the participants' median (MADe)
Total sent samples
85
Not examined
3
Non returns
2
Late returns
0
The data in FEPTU reports is confidential
Page 4 of 18
Printed at 10:57 on Thursday, 21 December, 2017
S81A: Coliform bacteria
25
Outlying results
72 Participant Median 63 FEPTU Median
Outlying results
30
No. of Results
20
15
10
>228
207-228
196-206
185-195
174-184
163-173
152-162
141-151
130-140
119-129
97-107
86-96
75-85
64-74
54-63
44-53
34-43
23-33
228
207-228
196-206
185-195
174-184
163-173
152-162
141-151
130-140
119-129
108-118
97-107
86-96
75-85
64-74
54-63
44-53
34-43
23-33
0
199
180-199
170-179
160-169
150-159
140-149
130-139
120-129
110-119
92-100
83-91
74-82
65-73
56-64
47-55
38-46
29-37
20-28
199
180-199
170-179
160-169
150-159
140-149
130-139
120-129
110-119
101-109
92-100
83-91
74-82
65-73
56-64
47-55
38-46
29-37
20-28
0
2.44
2.37-2.44
2.32-2.36
2.28-2.31
2.24-2.27
2.20-2.23
2.16-2.19
2.12-2.15
2.08-2.11
2.03-2.07
1.99-2.02
1.95-1.98
1.91-1.94
1.87-1.90
1.83-1.86
1.78-1.82
1.74-1.77
1.70-1.73
1.66-1.69
1.62-1.65
1.58-1.61
2.44
2.37-2.44
2.32-2.36
2.28-2.31
2.24-2.27
2.20-2.23
2.16-2.19
2.12-2.15
2.08-2.11
2.03-2.07
1.99-2.02
1.95-1.98
1.91-1.94
1.87-1.90
1.83-1.86
1.78-1.82
1.74-1.77
1.70-1.73
1.66-1.69
1.62-1.65
1.58-1.61
1.53-1.57
1.49-1.52
1.45-1.48
0
2.72
2.64-2.72
2.60-2.63
2.55-2.59
2.51-2.54
2.47-2.50
2.42-2.46
2.38-2.41
2.34-2.37
2.29-2.33
2.25-2.28
2.21-2.24
2.16-2.20
2.12-2.15
2.08-2.11
2.03-2.07
1.99-2.02
1.95-1.98
1.90-1.94
1.86-1.89
1.82-1.85
1.77-1.81
2.72
2.64-2.72
2.60-2.63
2.55-2.59
2.51-2.54
2.47-2.50
2.42-2.46
2.38-2.41
2.34-2.37
2.29-2.33
2.25-2.28
2.21-2.24
2.16-2.20
2.12-2.15
2.08-2.11
2.03-2.07
1.99-2.02
1.95-1.98
1.90-1.94
1.86-1.89
1.82-1.85
1.77-1.81
1.73-1.76
1.60-1.72
0
2.30
2.18-2.30
2.08-2.18
2.03-2.07
1.98-2.02
1.93-1.97
1.88-1.92
1.83-1.87
1.78-1.82
1.73-1.77
1.68-1.72
1.62-1.67
1.57-1.61
1.52-1.56
1.47-1.51
1.42-1.46
1.37-1.41
1.32-1.36
1.27-1.31
1.22-1.26
1.17-1.21
1.11-1.16
2.30
40
1.60 Participant Median 1.97 FEPTU Median
Outlying results
45
Outlying results
50
2.18-2.30
S81B: Escherichia coli
30 25 20 15 10 5
2.08-2.18
2.03-2.07
1.98-2.02
1.93-1.97
1.88-1.92
1.83-1.87
1.78-1.82
1.73-1.77
1.68-1.72
1.62-1.67
1.57-1.61
1.52-1.56
1.47-1.51
1.42-1.46
1.37-1.41
1.32-1.36
1.27-1.31
1.22-1.26
1.17-1.21
1.11-1.16
1.06-1.10
1.01-1.05
0
2.46
2.39-2.46
2.34-2.38
2.30-2.33
2.26-2.29
2.22-2.25
2.18-2.21
2.14-2.17
2.09-2.13
2.05-2.08
2.01-2.04
1.97-2.00
1.93-1.96
1.89-1.92
1.85-1.88
1.80-1.84
1.76-1.79
1.72-1.75
1.68-1.71
1.64-1.67
1.60-1.63
1.55-1.59
2.46
2.39-2.46
2.34-2.38
2.30-2.33
2.26-2.29
2.22-2.25
2.18-2.21
2.14-2.17
2.09-2.13
2.05-2.08
2.01-2.04
1.97-2.00
1.93-1.96
1.89-1.92
1.85-1.88
1.80-1.84
1.76-1.79
1.72-1.75
1.68-1.71
1.64-1.67
1.60-1.63
1.55-1.59
1.51-1.54
1.47-1.50
0
2.41
2.30-2.41
2.25-2.29
2.19-2.24
2.13-2.18
2.07-2.12
2.01-2.06
1.96-2.00
1.90-1.95
1.84-1.89
1.78-1.83
1.73-1.77
1.67-1.72
1.61-1.66
1.55-1.60
1.50-1.54
1.44-1.49
1.38-1.43
1.32-1.37
1.26-1.31
1.21-1.25
1.15-1.20
2.41
2.30-2.41
2.25-2.29
2.19-2.24
2.13-2.18
2.07-2.12
2.01-2.06
1.96-2.00
1.90-1.95
1.84-1.89
1.78-1.83
1.73-1.77
1.67-1.72
1.61-1.66
1.55-1.60
1.50-1.54
1.44-1.49
1.38-1.43
1.32-1.37
1.26-1.31
1.21-1.25
1.15-1.20
1.09-1.14
0.89-1.08
0
2.95
2.88-2.95
2.83-2.87
2.79-2.82
2.75-2.78
2.70-2.74
2.66-2.69
2.62-2.65
2.57-2.61
2.53-2.56
2.49-2.52
2.44-2.48
2.40-2.43
2.36-2.39
2.31-2.35
2.27-2.30
2.23-2.26
2.18-2.22
2.14-2.17
2.10-2.13
2.05-2.09
2.95
2.88-2.95
2.83-2.87
2.79-2.82
2.75-2.78
2.70-2.74
2.66-2.69
2.62-2.65
2.57-2.61
2.53-2.56
2.49-2.52
2.44-2.48
2.40-2.43
2.36-2.39
2.31-2.35
2.27-2.30
2.23-2.26
2.18-2.22
2.14-2.17
2.10-2.13
2.05-2.09
2.01-2.04
1.96-2.00
1.86-1.95
0
Recreational and Surface Water Scheme Distribution Number: S81
Sample Numbers: S81A, S81B
Distribution Date: Results Due: Report Date:
November 2017 08 December 2017 21 December 2017
Samples prepared and quality control tested by:
Angela Appea Richard Borrill Thomas Harper Zak Prior Judith Spellar Aneta Stranc Lili Tsegaye
Data analysed by:
Joanna Donn Nita Patel
Report compiled by:
Joanna Donn Nita Patel
Authorised by:
Nita Patel
This report must not be reproduced without permission of the organisers. Public Health England Food and Environmental Proficiency Testing Unit (FEPTU) 61 Colindale Avenue London NW9 5EQ Tel: +44 (0)20 8327 7119 Fax: +44 (0)20 8200 8264 Email: [email protected] The data in FEPTU reports is confidential
Page 1 of 18
Printed at 10:57 on Thursday, 21 December, 2017
For further information on the scheme please refer to: Scheme Guide: https://www.gov.uk/government/publications/food-and-water-proficiency-testing-schemes-scheme-guide Guide to Scoring and Statistics: https://www.gov.uk/government/publications/food-and-water-proficiency-testing-schemes-scoring-systems-and-statistics
General guidance for z-scores: Participants' enumeration results are converted into z-scores using the following formula:
Z = (xi-Xpt) σpt
xi Xpt
= participants' result expressed (expressed as a log 10 value) = assigned value (participants' consensus median (expressed as a log 10 value)
σpt
= the fixed standard deviation for the examination (calculated by FEPTU)
The σpt-value expresses the acceptable difference between the individual participant 's result and the participants' consensus median. The σpt-value used for calculating z-scores for all parameters in the Recreational and Surface Water Scheme is 0.35. A guide to interpreting z-scores follows, although laboratories must interpret their scores in the context of their own laboratory situation. z = -1.99 to +1.99 z = -2 to -2.99 or +2 to +2.99 z= < -3.00 or > + 3.00
satisfactory questionable unsatisfactory
It is usually recommended that z-scores exceeding +/-2 are investigated to establish the possible cause. general rule, PHE recommends that all questionable and unsatisfactory results are investigated.
As a
FEPTU Quality Control: To demonstrate homogeneity of the sample, a minimum of 10 LENTICULE® discs , selected randomly from a batch, are tested in duplicate for parameters requiring enumeration.
To demonstrate stability of the sample, a minimum of nine LENTICULE discs, selected randomly from a batch , are examined throughout the distribution period for enumeration parameters. PHE uses methods stipulated in the Microbiology of Recreational and Environmental Waters (2000) and the DWI’s series of documents: The Microbiology of Drinking Water (2002) - Methods for the Examination of Waters and Associated Materials. The FEPTU results are used for guidance in the preliminary intended results notification, letters are posted on the website immediately after every distribution; electronic notification of their availability is sent to all participants. Refer to section 17.0 of the Scheme Guide if you have experienced difficulties with any of the examinations . https://www.gov.uk/government/publications/food-and-water-proficiency-testing-schemes-scheme-guide
Participants are reminded that reporting an incorrect or false negative results for water samples could have serious public health implications. Participants who report unexpectedly high or low results for enumerations on single occasions only should not be unduly alarmed, although they should still assess the reason(s) for the outlying result.
Please contact FEPTU staff for advice and information: Repeat samples
Carmen Gomes or Kermin Daruwalla
Data Analysis
Manchari Rajkumar or Nita Patel
Microbiological advice
Nita Patel or Zak Prior
General comments and complaints
Nita Patel or Zak Prior
Scheme consultants
Julie E. Russell
Scheme Co-ordinator
Nita Patel
Tel: +44 (0)20 8327 7119 Fax: +44 (0)20 8200 8264 Email: [email protected] FEPTU's website
Accreditation: PHE Water EQA Scheme for Recreational and Surface Water is accredited by the United Kingdom Accreditation Service (UKAS) to ISO/IEC 17043:2010.
0006 The data in FEPTU reports is confidential
Page 2 of 18
Printed at 10:57 on Thursday, 21 December, 2017
Sample: S81A Water sample from river, lake and stream
Contents:
Enterobacter cloacae (wild strain), Enterococcus faecium (wild strain), Clostridium perfringens (wild strain), Salmonella Derby 1,4,[5],12:f,g:[1,2] (wild strain), Providencia rettgeri (NCTC 7475)
Expected Results: All counts are expressed as colony forming units (cfu) per 100mL. The fixed standard deviation value (σpt value) used for calculation of the z-scores is 0.35 for all parameters.
Parameter
FEPTU median
Coliform bacteria
Escherichia coli
Enterococci
Faecal coliforms
63
0
59
0
Clostridium perfringens
Salmonella spp.
75
Detected in
(1.88 log₁₀)
1L
No. results returned
68
77
71
34
58
45
Assigned value
72
0
63
0
87
N/A
(Participants
(1.94 log₁₀)
median all results) Uncertainty of
0.02
N/A
0.01
N/A
0.03
N/A
71
0
63
0
83
N/A
assigned value* Participants mean (all results)
(1.92 log₁₀)
Expected Range
23 - 228
N/A
20 - 199
N/A
28 - 2.75x10²
N/A
0.14
N/A
0.09
N/A
0.15
N/A
1
N/A
2
N/A
3
N/A
False positives
N/A
2
N/A
6
N/A
N/A
False negatives
1
N/A
1
N/A
1
0
Standard deviation** No of outlying counts
Your result
Score for performance assessment Z-score
*
U(Xpt) is based on results transformed to a log₁₀ scale
**
Robust S* based on median absolute deviation about the participants' median (MADe)
Total sent samples
85
Not examined
4
Non returns
2
Late returns
0
The data in FEPTU reports is confidential
Page 3 of 18
Printed at 10:57 on Thursday, 21 December, 2017
Sample: S81B Water sample from river, lake and stream
Contents:
Escherichia coli (wild strain), Klebsiella pneumoniae (wild strain), Enterococcus faecalis (wild strain), Clostridium perfringens (wild strain), Salmonella Stanley 1,4,[5],12,[27]:d:1,2 (wild strain)
Expected Results: All counts are expressed as colony forming units (cfu) per 100mL. The fixed standard deviation value (σpt value) used for calculation of the z-scores is 0.35 for all parameters.
Parameter
FEPTU median
Coliform bacteria
Escherichia coli
Enterococci
Faecal coliforms
Clostridium perfringens
Salmonella spp.
1.07x10²
93
81
1.01x10²
2.90x10²
Detected in
(2.03 log₁₀)
(1.97 log₁₀)
(1.91 log₁₀)
(2 log₁₀)
(2.46 log₁₀)
1L
68
77
71
35
58
45
1.65x10²
40
91
81
2.85x10²
N/A
(2.22 log₁₀)
(1.6 log₁₀)
(1.96 log₁₀)
(1.91 log₁₀)
(2.45 log₁₀)
0.03
0.1
0.01
0.1
0.04
N/A
1.58x10²
94
90
69
2.68x10²
N/A
(2.2 log₁₀)
(1.97 log₁₀)
(1.95 log₁₀)
(1.84 log₁₀)
(2.43 log₁₀)
52 - 5.22x10²
10 - 1.50x10²
29 - 2.88x10²
12 - 2.56x10²
90 - 9.00x10²
N/A
0.2
0.28
0.08
0.43
0.21
N/A
5
38
0
5
4
N/A
False positives
N/A
N/A
N/A
N/A
N/A
N/A
False negatives
0
35
0
0
1
2
No. results returned
Assigned value (Participants median all results) Uncertainty of assigned value* Participants mean (all results) Expected Range
Standard deviation** No of outlying counts
Your result
Score for performance assessment Z-score
*
U(Xpt) is based on results transformed to a log₁₀ scale
**
Robust S* based on median absolute deviation about the participants' median (MADe)
Total sent samples
85
Not examined
3
Non returns
2
Late returns
0
The data in FEPTU reports is confidential
Page 4 of 18
Printed at 10:57 on Thursday, 21 December, 2017
S81A: Coliform bacteria
25
Outlying results
72 Participant Median 63 FEPTU Median
Outlying results
30
No. of Results
20
15
10
>228
207-228
196-206
185-195
174-184
163-173
152-162
141-151
130-140
119-129
97-107
86-96
75-85
64-74
54-63
44-53
34-43
23-33
228
207-228
196-206
185-195
174-184
163-173
152-162
141-151
130-140
119-129
108-118
97-107
86-96
75-85
64-74
54-63
44-53
34-43
23-33
0
199
180-199
170-179
160-169
150-159
140-149
130-139
120-129
110-119
92-100
83-91
74-82
65-73
56-64
47-55
38-46
29-37
20-28
199
180-199
170-179
160-169
150-159
140-149
130-139
120-129
110-119
101-109
92-100
83-91
74-82
65-73
56-64
47-55
38-46
29-37
20-28
0
2.44
2.37-2.44
2.32-2.36
2.28-2.31
2.24-2.27
2.20-2.23
2.16-2.19
2.12-2.15
2.08-2.11
2.03-2.07
1.99-2.02
1.95-1.98
1.91-1.94
1.87-1.90
1.83-1.86
1.78-1.82
1.74-1.77
1.70-1.73
1.66-1.69
1.62-1.65
1.58-1.61
2.44
2.37-2.44
2.32-2.36
2.28-2.31
2.24-2.27
2.20-2.23
2.16-2.19
2.12-2.15
2.08-2.11
2.03-2.07
1.99-2.02
1.95-1.98
1.91-1.94
1.87-1.90
1.83-1.86
1.78-1.82
1.74-1.77
1.70-1.73
1.66-1.69
1.62-1.65
1.58-1.61
1.53-1.57
1.49-1.52
1.45-1.48
0
2.72
2.64-2.72
2.60-2.63
2.55-2.59
2.51-2.54
2.47-2.50
2.42-2.46
2.38-2.41
2.34-2.37
2.29-2.33
2.25-2.28
2.21-2.24
2.16-2.20
2.12-2.15
2.08-2.11
2.03-2.07
1.99-2.02
1.95-1.98
1.90-1.94
1.86-1.89
1.82-1.85
1.77-1.81
2.72
2.64-2.72
2.60-2.63
2.55-2.59
2.51-2.54
2.47-2.50
2.42-2.46
2.38-2.41
2.34-2.37
2.29-2.33
2.25-2.28
2.21-2.24
2.16-2.20
2.12-2.15
2.08-2.11
2.03-2.07
1.99-2.02
1.95-1.98
1.90-1.94
1.86-1.89
1.82-1.85
1.77-1.81
1.73-1.76
1.60-1.72
0
2.30
2.18-2.30
2.08-2.18
2.03-2.07
1.98-2.02
1.93-1.97
1.88-1.92
1.83-1.87
1.78-1.82
1.73-1.77
1.68-1.72
1.62-1.67
1.57-1.61
1.52-1.56
1.47-1.51
1.42-1.46
1.37-1.41
1.32-1.36
1.27-1.31
1.22-1.26
1.17-1.21
1.11-1.16
2.30
40
1.60 Participant Median 1.97 FEPTU Median
Outlying results
45
Outlying results
50
2.18-2.30
S81B: Escherichia coli
30 25 20 15 10 5
2.08-2.18
2.03-2.07
1.98-2.02
1.93-1.97
1.88-1.92
1.83-1.87
1.78-1.82
1.73-1.77
1.68-1.72
1.62-1.67
1.57-1.61
1.52-1.56
1.47-1.51
1.42-1.46
1.37-1.41
1.32-1.36
1.27-1.31
1.22-1.26
1.17-1.21
1.11-1.16
1.06-1.10
1.01-1.05
0
2.46
2.39-2.46
2.34-2.38
2.30-2.33
2.26-2.29
2.22-2.25
2.18-2.21
2.14-2.17
2.09-2.13
2.05-2.08
2.01-2.04
1.97-2.00
1.93-1.96
1.89-1.92
1.85-1.88
1.80-1.84
1.76-1.79
1.72-1.75
1.68-1.71
1.64-1.67
1.60-1.63
1.55-1.59
2.46
2.39-2.46
2.34-2.38
2.30-2.33
2.26-2.29
2.22-2.25
2.18-2.21
2.14-2.17
2.09-2.13
2.05-2.08
2.01-2.04
1.97-2.00
1.93-1.96
1.89-1.92
1.85-1.88
1.80-1.84
1.76-1.79
1.72-1.75
1.68-1.71
1.64-1.67
1.60-1.63
1.55-1.59
1.51-1.54
1.47-1.50
0
2.41
2.30-2.41
2.25-2.29
2.19-2.24
2.13-2.18
2.07-2.12
2.01-2.06
1.96-2.00
1.90-1.95
1.84-1.89
1.78-1.83
1.73-1.77
1.67-1.72
1.61-1.66
1.55-1.60
1.50-1.54
1.44-1.49
1.38-1.43
1.32-1.37
1.26-1.31
1.21-1.25
1.15-1.20
2.41
2.30-2.41
2.25-2.29
2.19-2.24
2.13-2.18
2.07-2.12
2.01-2.06
1.96-2.00
1.90-1.95
1.84-1.89
1.78-1.83
1.73-1.77
1.67-1.72
1.61-1.66
1.55-1.60
1.50-1.54
1.44-1.49
1.38-1.43
1.32-1.37
1.26-1.31
1.21-1.25
1.15-1.20
1.09-1.14
0.89-1.08
0
2.95
2.88-2.95
2.83-2.87
2.79-2.82
2.75-2.78
2.70-2.74
2.66-2.69
2.62-2.65
2.57-2.61
2.53-2.56
2.49-2.52
2.44-2.48
2.40-2.43
2.36-2.39
2.31-2.35
2.27-2.30
2.23-2.26
2.18-2.22
2.14-2.17
2.10-2.13
2.05-2.09
2.95
2.88-2.95
2.83-2.87
2.79-2.82
2.75-2.78
2.70-2.74
2.66-2.69
2.62-2.65
2.57-2.61
2.53-2.56
2.49-2.52
2.44-2.48
2.40-2.43
2.36-2.39
2.31-2.35
2.27-2.30
2.23-2.26
2.18-2.22
2.14-2.17
2.10-2.13
2.05-2.09
2.01-2.04
1.96-2.00
1.86-1.95
0
