# The Surface Waters (Abstraction for Drinking Water) (Classification) Regulations (Northern Ireland) 1996, Part: Part I

Extent: N.I.
Status: prospective

No. in Annex 1 to 79/869 /EEC
Parameters
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 For values in the column of Category DW1 in Schedule 1.
5 For waters classified as DW2 or DW3.
6 For waters classified as DW3.
7 For values in the I columns of Schedule 1.
8 For values in the I column of Category DWI, and values in Category DW3 in Schedule 1.
9 For values in the G columns of Categories DW2 and DW3 in Schedule 1
10 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; indano/1, 2, 3-cd/pyrene.
11 Mixture of three substances all of the same concentration to be taken into consideration; parathion, hexachlorocyclohexane, dieldrin.
12 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. The samples must be treated so as to ensure that the analysis covers the largest quantity of substances to be measured.
13 As this method is not in current use in all Member States it is not certain that the limit of detection required for checking values can be attained.
14 Absence in this volume for values in the G column of Category DW1 in Schedule 1.
15 Absence in this volume for values in the G column of Category DW2 in Schedule 1.
1
pH
pH unit
—
0.1
0.2
Electrometry, measured in situ at the time of sampling without prior treatment of the sample.
2
Coloration (after simple filtration)
mg/l Pt Scale
5
10%
20%
Filtering through a glass fibre membrane. Photometric method using platinum-cobalt scale.
3
Total suspended solids
mg/l SS
—
5%
10%
Filtering through a 0.45 μm filter membrane, drying at 105°C and weighing. Centrifuging (for at least 5 mins with mean acceleration of 2,800 to 3,200 g), drying at 105°C and weighing.
4
Temperature
°C
—
0.5
1
Thermometry. Measured in situ at the time of sampling without prior treatment of the sample.
5
Conductivity at 20°C
μs/cm
—
5%
10%
Electrometry.
6
Odour
(dilution factor at 25°C)
—
—
—
By successive dilutions.
Glass.
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/1 Fe
0.02
10%
20%
Atomic absorption spectrophotometry after filtering through a filter membrane (0.45 μm). Molecular absorption spectrophotometry after filtering through a 0.45 μm filter membrane.
11
Manganese
mg/l Mn
0.01
0.02
10%
10%
20%
20%
Atomic absorption spectrophotometry.
Atomic absorption spectrophotometry. Molecular absorption spectrophotometry.
12
Copper
mg/l Cu
0.005
0.02
10%
10%
20%
20%
Atomic absorption spectrophotometry. Polarography.
Atomic absorption spectrophotometry. Molecular absorption spectrophotometry. Polarography.
13
Zinc
mg/l Zn
0.01
0.02
10%
10%
20%
20%
Atomic absorption spectrophotometry.
Atomic absorption spectrophotometry. Molecular absorption spectrophotometry.
14
Boron
mg/l B
0.1
10%
20%
Molecular absorption spectrophotometry. Atomic absorption spectrophotometry.
Materials not containing boron in any significant quantities.
19
Arsenic
mg/l As
0.002
0.01
20%
10%
20%
20%
Atomic absorption spectrophotometry.
Atomic absorption spectrophotometry. Molecular absorption spectrophotometry.
20
Cadmium
mg/l Cd
0.0002
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/1 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
0.0001
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.
28
Chlorides
mg/l Cl
10
10%
10%
Titration (Mohr’s method). Molecular absorption spectrophotometry.
29
Surfactants (reacting with methylene blue)
mg/l (lauryl sulphate
0.05
20%
Molecular absorption spectrophotometry.
30
Phosphates
mg/l P2O5
0.02
10%
20%
Molecular absorption spectrophotometry.
31
Phenols (phenol index) parani-traniline 4 amino-antipyrene
mg/l C6H5OH
0.0005
0.001
0.0005
30%
0.0005
50%
Molecular absorption spectrophotometry. 4 aminoantipyrine method. Paranitraniline method.
Glass.
32
Dissolved or emulsified hydro- carbons (after extraction by petroleum ether)
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 hydro-carbons
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.
35
Chemical oxygen demand (COD)
mg/l O2
15
20%
20%
Potassium dichromate method.
36
Dissolved oxygen saturation rate
% O2
5
10%
10%
Winkler’s method. Electro-chemical method.
Glass.
37
Biochemical oxygen demand (BOD5) (at 20°C without nitrification)
mg/l O2
2
1.5
2
Determination of dissolved oxygen before and after five day incubation at 20°C ± 1°C in complete darkness. Addition of a nitrification inhibitor.
38
Nitrogen, Kjeldahl method (except NO2 or NO3)
mg/l N
0.3
0.5
0.5
Mineralisation, distillation by the Kjeldahl method and ammonium determination by means of molecular absorption spectrophotometry or titration.
39
Ammonium
mg/l NH4
0.01
0.1
0.03
10%
0.03
20%
Molecular absorption spectrophotometry.
40
Substances extractable with chloroform
mg/l
()
Extraction at neutral pH value by purified chloroform, evaporation in vacuo at room temperature, weighing of residue.
43
Total coliforms
/100 ml
5
500
Culture at 37°C on an appropriate specific solid medium (such as Tergitol lactose agar, Endo agar, 0.4% Teepol broth) with filtration or without filtration and colony count. Samples must be diluted or, where appropriate, concentrated in such a way as to contain between 10 and 100 colonies. If necessary, identification by gasification.
Alternative method:— Method of dilution with fermentation in liquid substrates in at least three tubes in three dilutions. Sub-culturing of the positive tubes on a confirmation medium. Count according to MPN (most probable number). Incubation temperature 37°C ± 1°C.
Sterilised glass.
44
Faecal coliforms
/100 ml
2
200
Culture at 44°C on an appropriate specific solid medium (such as Tergitol lactose agar, Endo agar, 0.4% Teepol broth) with filtration or without filtration and colony count. Samples must be diluted or, where appropriate, concentrated in such a way as to contain between 10 and 100 colonies. If necessary, identification by gasification.
Alternative method:— Method of dilution with fermentation in liquid substrates in at least three tubes in three dilutions. Sub-culturing of the positive tubes on a confirmation medium. Count according to MPN (most probable number). Incubation temperature 44°C ± 0.5°C.
Sterilised glass.
45
Faecal streptococci
/100 ml
2
200
Culture at 37°C on an appropriate specific solid medium (such as sodium azide) with filtration or without filtration and colony count. Samples must be diluted or, where appropriate, concentrated in such a way as to contain between 10 and 100 colonies.
Alternative method:— Method of dilution in sodium azide broth in at least three tubes in three dilutions. Count according to MPN (most probable number.
46
Salmonella
1/5,000 ml
1/1,000 ml
Concentration by filtration (on membrane or appropriate filter). Inoculation into pre-enrichment medium. Enrichment and transfer into isolating gelese. Identification.
Sterilised glass.

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Source: https://www.legislation.gov.uk/nisr/1996/603/schedule/2/part/1 (the official version)
Page: https://openlegislation.uk/surface-waters-abstraction-for-drinking-water-classification-regulations-northern-ireland-1996/schedule-2/part-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.