Health-based reference values from the WHO Guidelines for Drinking-water Quality — the benchmark SANS 241:2015 nominates for any determinand not tabulated in the South African standard.
WHO GDWQ · 4th edition (2017) with 1st (2018) and 2nd (2022) addenda
| Organism | Guideline value |
|---|---|
| Escherichia coli or thermotolerant coliforms | Must not be detectable in any 100 mL sample |
| Total coliforms (distribution system, treated water) | Must not be detectable in any 100 mL sample |
P = provisional guideline value.
| Determinand | Guideline value |
|---|---|
| Antimony | 0.020 mg/L |
| Arsenic | 0.010 mg/L (P) |
| Barium | 1.3 mg/L |
| Boron | 2.4 mg/L |
| Cadmium | 0.003 mg/L |
| Chromium (total) | 0.050 mg/L (P) |
| Copper | 2 mg/L |
| Cyanide (long-term) | 0.070 mg/L |
| Fluoride | 1.5 mg/L |
| Lead | 0.010 mg/L (P, AMDL) |
| Manganese | 0.080 mg/L |
| Mercury (inorganic) | 0.006 mg/L |
| Molybdenum | 0.070 mg/L |
| Nickel | 0.070 mg/L |
| Nitrate (as NO₃⁻) | 50 mg/L (short-term) |
| Nitrite (as NO₂⁻) | 3 mg/L (short-term) |
| Selenium | 0.040 mg/L (P) |
| Uranium | 0.030 mg/L (P) |
| Determinand | Guideline value |
|---|---|
| Bromate | 0.010 mg/L (P) |
| Bromodichloromethane | 0.060 mg/L |
| Bromoform | 0.100 mg/L |
| Chlorate | 0.700 mg/L (P) |
| Chlorite | 0.700 mg/L (P) |
| Chloroform | 0.300 mg/L |
| Dibromoacetonitrile | 0.070 mg/L |
| Dibromochloromethane | 0.100 mg/L |
| Dichloroacetate | 0.050 mg/L (P) |
| Trichloroacetate | 0.200 mg/L |
| Trihalomethanes (sum of ratios) | ≤ 1 |
Values below which most consumers find water aesthetically acceptable.
| Determinand | Level of concern |
|---|---|
| Colour | 15 TCU |
| Turbidity | ≤ 1 NTU (verification); ≤ 4 NTU (acceptable) |
| pH | 6.5 – 8.5 |
| Chloride | 250 mg/L |
| Sulphate | 250 mg/L |
| Sodium | 200 mg/L |
| Aluminium | 0.1 – 0.2 mg/L (depending on plant) |
| Iron | 0.3 mg/L |
| Manganese | 0.1 mg/L |
| Zinc | 3 mg/L |
| Total dissolved solids | 1 000 mg/L (indicative) |
Values shown are health-based guideline values (GV) from the WHO Guidelines for Drinking-water Quality (WHO, 2022). Where a WHO GV is provisional or based on a lower detection limit than the corresponding SANS 241 numeric limit, the stricter of the two applies to the site.