The sources of Greywater are water discharged from showers, bathtubs, wash basins and laundry. As this is untreated used water not in contact with toilet waste, it excludes water from urinals, toilet bowls (water closets), kitchen sinks and dishwashers.
Before Greywater can be reused for non-potable purposes like toilet flushing, general washing and irrigation as well as make-up water in cooling tower, it has to go through membrane filtration for disinfection. Certain safety requirements for Treated Greywater must still be met.
For public health reasons, it is however prohibited to use Treated Greywater for high-pressure jet washing, irrigation sprinklers and general washing at markets and food establishments.
Guidance Notes for Treated Greywater Quality [PDF].
Technical Guide for Greywater Recycling System [PDF].