PART 2 N.I.Methods of analysis and performance characteristics
Table 1
Prescribed methods of analysis
1 Use the following method to make m-CP agar: | |
Parameter | Method |
---|---|
Clostridium perfringens (including spores) | Membrane filtration followed by anaerobic incubation of the membrane on m-CP agar1 at 44 ±1ºC for 21± 3 hours. Count opaque yellow colonies that turn pink or red after exposure to ammonium hydroxide vapours for 20 to 30 seconds. |
Coliform bacteria | BS-EN ISO 9308-1 |
Colony count 22ºC – enumeration of culturable microorganisms | BS-EN ISO 6222 |
Colony count 37ºC – enumeration of culturable microorganisms | BS-EN ISO 6222 |
Enterococci | BS-EN ISO 7899-2 |
Escherichia coli (E. Coli) | BS-EN ISO 9308-1 |
Pseudomonas aeruginosa | BS-EN ISO 12780 |
Make a basal medium consisting of—
Tryptose | 30.0g |
Yeast extract | 20.0g |
Sucrose | 5.0g |
L-cysteine hydrochloride | 1.0g |
MgSO4.7H2O | 0.1g |
Bromocresol purple | 40.0mg |
Agar | 15.0g |
Water | 1,000.0ml |
Dissolve the ingredients of basal medium, adjust pH to 7.6 and autoclave at 121ºC for 15 minutes. Allow the medium to cool. | |
Dissolve— | |
D-cycloserine | 400.0mg |
Polymyxine-B sulphate | 25.0mg |
Indoxl-β-D-glucoside | 60.0mg |
into 8ml sterile water and add it to the medium. | |
Add to the medium— | |
Filter-sterilised 0.5% phenolphthalein diphosphate solution | 20.0ml |
Filter-sterilised 4.5% FeCl3.6H2O | 2.0ml |
Table 2
Prescribed performance characteristics for methods of analysis
1 The method of analysis should determine total cyanide in all forms. | |||
2 Oxidation should be carried out for 10 minutes at 100ºC under acid conditions using permanganate. | |||
3 The performance characteristics apply to each individual pesticide and will depend on the pesticide concerned. | |||
4 The performance characteristics apply to the individual substances specified at 25% of the parametric value in Table B in Part 2, Schedule 7. | |||
5 The performance characteristics apply to the individual substance specified at 50% of the parametric value in Table B in Part 2, Schedule 7. | |||
Parameters | Trueness % of prescribed concentration or value specification | Precision % of prescribed concentration or value or specification | Limit of detection % of prescribed concentration or value or specification |
---|---|---|---|
Aluminium | 10 | 10 | 10 |
Ammonium | 10 | 10 | 10 |
Antimony | 25 | 25 | 25 |
Arsenic | 10 | 10 | 10 |
Benzene | 25 | 25 | 25 |
Benzo(a)pyrene | 25 | 25 | 25 |
Boron | 10 | 10 | 10 |
Bromate | 25 | 25 | 25 |
Cadmium | 10 | 10 | 10 |
Chloride | 10 | 10 | 10 |
Chromium | 10 | 10 | 10 |
Conductivity | 10 | 10 | 10 |
Copper | 10 | 10 | 10 |
Cyanide1 | 10 | 10 | 10 |
1,2-dichloroethane | 25 | 25 | 10 |
Fluoride | 10 | 10 | 10 |
Iron | 10 | 10 | 10 |
Lead | 10 | 10 | 10 |
Manganese | 10 | 10 | 10 |
Mercury | 20 | 10 | 20 |
Nickel | 10 | 10 | 10 |
Nitrate | 10 | 10 | 10 |
Nititre | 10 | 10 | 10 |
Oxidisability2 | 25 | 25 | 10 |
Pesticides and related products3 | 25 | 25 | 25 |
Polycyclic aromatic hydrocarbons4 | 25 | 25 | 25 |
Selenium | 10 | 10 | 10 |
Sodium | 10 | 10 | 10 |
Sulphate | 10 | 10 | 10 |
Tetrachloroethene5 | 25 | 25 | 10 |
Tetrachloromethane | 20 | 20 | 20 |
Trichloroethene5 | 25 | 25 | 10 |
Trihalomethanes4 | 25 | 25 | 10 |