# The Surface Waters (Abstraction for Drinking Water) (Classification) Regulations 1996, Part I: METHOD OF MEASURING THE VALUES OF PARAMETERS


No. in Annex II to 75/440/EEC
Parameters
Units
Limit of detection
Precision
Accuracy
Method of measurement
Materials recommended for the container
1 “Limit of detection” means the minimum value of the parameter examined which it is possible to detect.
2 “Precision” means the range within which 95% of the results of measurements made on a single sample, using the same method, are located.
3 “Accuracy” means the difference between the true value of the parameter examined and the average experimental value obtained.
4 If the samples contain so much suspended matter as to require special preliminary treatment, the accuracy values shown in the above Table may as an exception be exceeded and are to be regarded as a target. These samples must be treated so as to ensure that the analysis covers the largest quantity of substances to be measured.
5 For waters classified as DW1 or DW2.
6 For waters classified as DW3.
7 For waters classified as DW1.
8 For waters classified as DW2 or DW3.
9 Mixture of six standard substances all of the same concentration to be taken into consideration: fluoranthene; 3,4-benzofluoranthene; 11, 12-benzofluoranthene; 3,4-benzopyrene; 1,12-benzoperylene; indeno (1,2,3-cd) pyrene.
10 Mixture of three substances all of the same concentration to be taken into consideration: parathion, hexachlorocyclohexane, dieldrin.
2
Coloration (after simple filtration)
mg/l Pt Scale
5
10%
20%
Filtering through a glass fibre membrane.
Photometric method using platinum-cobalt scale.
4
Temperature
°C
—
0.5
1
Thermometry.
Measured in situ at the time of sampling without prior treatment of the sample.
7
Nitrates
mg/l NO3
2
10%
20%
Molecular absorption spectrophotometry.
8
Fluorides
mg/l F
0.05
10%
20%
Molecular absorption spectrophotometry after distillation if necessary.
Ion selective electrodes.
10
Dissolved iron
mg/l Fe
0.02
10%
20%
Atomic absorption spectrophotometry after filtering through 0.45 μm filter membrane.
Molecular absorption spectrophotometry after filtering through 0.45 μm filter membrane.
12
Copper
mg/l Cu
0.005
10%
20%
Atomic absorption spectrophotometry.
Polarography.
13
Zinc
mg/l Zn
0.02
10%
20%
Atomic absorption spectrophotometry.
Molecular absorption spectrophotometry.
19
Arsenic
mg/l As
0.01
10%
20%
Atomic absorption spectrophotometry.
Molecular absorption spectrophotometry.
20
Cadmium
mg/l Cd
0.001
30%
30%
Atomic absorption spectrophotometry.
Polarography.
21
Total chromium
mg/l Cr
0.01
20%
30%
Atomic absorption spectrophotometry.
Molecular absorption spectrophotometry.
22
Lead
mg/l Pb
0.01
20%
30%
Atomic absorption spectrophotometry.
Polarography.
23
Selenium
mg/l Se
0.005
10%
10%
Atomic absorption spectrophotometry.
24
Mercury
mg/l Hg
0.0002
30%
30%
Flameless atomic absorption spectrophotometry (cold vaporisation).
25
Barium
mg/l Ba
0.02
15%
30%
Atomic absorption spectrophotometry.
26
Cyanide
mg/l CN
0.01
20%
30%
Molecular absorption spectrophotometry.
27
Sulphates
mg/l SO4
10
10%
10%
Gravimetric analysis.
EDTA compleximetry.
Molecular absorption spectrophotometry.
31
Phenols (phenol index) paranitraniline 4-aminoantipyrene
mg/l C6H5OH
0.0005 0.001
0.0005 30%
0.0005 50%
Molecular absorption spectrophotometry 4-aminoantipyrene method.
Paranitraniline method.
Glass.
32
Dissolved or emulsified hydrocarbons
mg/l
0.01 0.04
20% 20%
30% 30%
Infra-red spectrometry after extraction by carbon tetrachloride.
Gravimetry after extraction by petroleum ether.
Glass
33
Polycyclic aromatic hydrocarbons
mg/l
0.00004
50%
50%
Measurement of fluorescence in the UV after thin layer chromatography.
Comparative measurements in relation to a mixture of six control substances with the same concentration.
Glass or aluminium.
34
Total pesticides (parathion, hexachloro-cyclohexane, dieldrin)
mg/l
0.0001
50%
50%
Gas or liquid chromatography after extraction by suitable solvents and purification.
Identification of the constituents of the mixture.
Quantitative analysis.
Glass.
39
Ammonium
mg/l NH4
0.1
10%
20%
Molecular absorption spectrophotometry.

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Source: https://www.legislation.gov.uk/uksi/1996/3001/schedule/2/part/I (the official version)
Page: https://openlegislation.uk/surface-waters-abstraction-for-drinking-water-classification-regulations-1996/schedule-2/part-I
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.