The Surface Waters (Abstraction for Drinking Water) (Classification) Regulations (Northern Ireland) 1996 No. 603

regulation 8

SCHEDULE 2

Part IMethod of Measuring the Values of Parameters

No. in Annex 1 to 79/869 /EEC	Parameters		Limit of detection1	Precision2	Accuracy3	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	0.014 0.025	10%4 10%5	20%4 20%5	Atomic absorption spectrophotometry. Atomic absorption spectrophotometry. Molecular absorption spectrophotometry.
12	Copper12	mg/l Cu	0.005 0.026	10% 10%6	20% 20%6	Atomic absorption spectrophotometry. Polarography. Atomic absorption spectrophotometry. Molecular absorption spectrophotometry. Polarography.
13	Zinc12	mg/l Zn	0.014 0.02	10%4 10%	20%4 20%	Atomic absorption spectrophotometry. Atomic absorption spectrophotometry. Molecular absorption spectrophotometry.
14	Boron12	mg/l B	0.1	10%	20%	Molecular absorption spectrophotometry. Atomic absorption spectrophotometry.	Materials not containing boron in any significant quantities.
19	Arsenic12	mg/l As	0.0024 0.017	20%4 10%7	20%4 20%7	Atomic absorption spectrophotometry. Atomic absorption spectrophotometry. Molecular absorption spectrophotometry.
20	Cadmium12	mg/l Cd	0.0002 0.0017	30%	30%	Atomic absorption spectrophotometry. Polarography.
21	Total chromium12	mg/l Cr	0.01	20%	30%	Atomic absorption spectrophotometry. Molecular absorption spectrophotometry.
22	Lead12	mg/1 Pb	0.01	20%	30%	Atomic absorption spectrophotometry. Polarography.
23	Selenium12	mg/l Se	0.005	10%	10%	Atomic absorption spectrophotometry.
24	Mercury12	mg/l Hg	0.0001 0.00027	30%	30%	Flameless atomic absorption spectrophotometry (cold vaporisation).
25	Barium12	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 0.0018	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 0.045	20% 20%5	30% 30%5	Infra-red spectrometry after extraction by carbon tetrachloride. Gravimetry after extraction by petroleum ether.	Glass.
33	Polycyclic aromatic hydro-carbons12	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.10	Glass or aluminium.
34	Total pesticides (parathion, hexachloro- cyclohexane, dieldrin)12	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.11	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	0.014 0.15	0.034 10%5	0.034 20%5	Molecular absorption spectrophotometry.
40	Substances extractable with chloroform	mg/l	(13)			Extraction at neutral pH value by purified chloroform, evaporation in vacuo at room temperature, weighing of residue.
43	Total coliforms	/100 ml	54 5009			Culture at 37°C on an appropriate specific solid medium (such as Tergitol lactose agar, Endo agar, 0.4% Teepol broth) with filtration4 or without filtration9 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	24 2009			Culture at 44°C on an appropriate specific solid medium (such as Tergitol lactose agar, Endo agar, 0.4% Teepol broth) with filtration4 or without filtration9 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	24 2009			Culture at 37°C on an appropriate specific solid medium (such as sodium azide) with filtration4 or without filtration9 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 ml14 1/1,000 ml15				Concentration by filtration (on membrane or appropriate filter). Inoculation into pre-enrichment medium. Enrichment and transfer into isolating gelese. Identification.	Sterilised glass.

Part IIMinimum Annual Frequency of Sampling for each Parameter

Population Served	Classification DW1			Classification DW2			Classification DW3
	I1	II2	III3	I1	II2	III3	I1	II2	III3
1 This column applies to the parameters −pH, coloration, total suspended solids, temperature, conductivity, odour, nitrates, chlorides, phosphates, chemical oxygen demand (COD), dissolved oxygen saturation rate, biochemical oxygen demand (BOD5) and ammonium.
2 This column applies to the parameters — dissolved iron, manganese, copper, zinc, sulphates, surfactants, phenols, nitrogen by the Kjeldahl method, total coliforms and faecal coliforms.
3 This column applies to the parameters — fluorides, boron, arsenic, cadmium, total chromium, lead, selenium, mercury, barium, cyanide, dissolved or emulsified hydrocarbons, polycyclic aromatic hydrocarbons, total pesticides, substances extractable by chloroform, faecal streptococci and salmonella.
<10,000	1	1	1	1	1	1	2	1	1
> 10,000 to ≤30,000	1	1	1	2	1	1	3	1	1
>30,000 to ≤100,000	2	1	1	4	2	1	6	2	1
>100,000	3	2	1	8	4	1	12	4	1