Maximum
Permissible
Limits
of
Some
of
the
Parameters
of
Water
Quality
for
Water
Intended
for
Human
Consumption
-
UK
Water
Supply
Regulations
1989 -
| Parameter |
Maximum concentration / value |
Parameter |
Maximum concentration / value |
| Part A |
|
Chromium (µg/l) |
50 |
| Colour units |
20 |
Mercury (µg/l) |
1 |
| Turbidity units |
4 |
Lead (µg/l) |
50 |
| Odour (dilution number) |
3 at 25°C |
Nickel (µg/l) |
50 |
| Taste (dilution number) |
3 at 25°C |
Pesticides, total (µg/l) |
0.5 |
| pH value |
9.5 |
Polycyclic aromatic hydrocarbons, total (µg/l) |
0.2 |
| Temperature |
25°C |
Part C |
|
| Sulphate (mg/l) |
250 |
Total coliforms |
0/100 ml |
| Magnesium (mg/l) |
50 |
Faecal coliforms |
0/100 ml |
| Sodium (mg/l) |
150 |
Faecal streptococci |
0/100 ml |
| Potassium (mg/l) |
12 |
Sulphite redcucing clostridia |
< 1/100 ml |
| Dry residues (mg/l) |
1500 |
Part D |
|
| Nitrate (mg/l) |
50 |
Cloride (mg/l) |
400 |
| Nitrite (mg/l) |
0.1 |
Calcium (mg/l) |
200 |
| Ammonium (mg/l) |
0.5 |
Substances extratable in chloroform (mg/l dry residue) |
1 |
| Dissolved or emulsified hydrocarbons (µg/l) |
10 |
Boron (µg/l) |
2000 |
| Phenols (µg/l) |
0.5 |
Barium (µg/l) |
1000 |
| Surfactants (µg/l) |
200 |
Part E |
|
| Part B |
|
Total hardness (mg Ca/l) |
60 |
| Arsenic (µg/l) |
|
Alkalinity (mg HCO3/l) |
30 |
| Cyanide (µg/l) |
|
|
|
|
