| #P001 | operational | operational | recommended | pH | drinking water | requirement | 8.3 pH | The alternative is that all colour measurements be done at a standard pH of 8.3 | If not recording the actual pH with the colour measurement | medium |
| #P002 | operational | operational | recommended | Standard pH for colour measurement | drinking water | requirement | 8.3 pH | The alternative is that all colour measurements be done at a standard pH of 8.3 | Used as an alternative to recording the actual pH of the sample with the colour measurement | high |
| #P003 | physical | aesthetic | guideline | Colour detection threshold (glass of water) | drinking water | AO | 15 TCU | A colour of 15 TCU can be detected in a glass of water by most consumers | Visual detection in a glass of water | high |
| #P004 | physical | aesthetic | guideline | Colour detection threshold (large volumes) | drinking water | AO | 5 TCU | 5 TCU will be apparent in large volumes of water, such as in a bathtub | Visual detection in large volumes of water | high |
| #P005 | physical | aesthetic | guideline | Colour detection threshold (lower limit) | drinking water | AO | 3 TCU | few people can detect a colour level of 3 TCU | Visual detection threshold for minority of consumers | high |
| #P006 | chemical | operational | guideline | TCU standard solution platinum concentration | drinking water | requirement | 1.0 mg/L | One true colour unit (TCU), or platinum-cobalt unit, corresponds to the amount of colour exhibited under the specified test conditions by a standard solution containing 1.0 mg of platinum per litre. | Preparation of platinum-cobalt standard solutions for visual comparison method | high |