Water purifiers must mention wastage, efficiency rating: Officials

Manufacturers of reverse osmosis-based water purifiers will now have to rate their appliances on efficiency and water wastage, while water supply agencies will have to declare the total dissolved solids (TDS) in the water being supplied, according to officials.

The environment ministry has notified regulations for water purification systems which will come into effect 18 months from now. The move is aimed at allowing consumers to make informed decisions on the kind of water purifier needed, if at all, the officials cited earlier told ET.

The regulations follow the National Green Tribunal's advice to the environment ministry on May 20, 2019 that it should come out with regulation on appropriate use of RO-based water purification systems.


Accordingly, the regulations have tasked all agencies and organisations engaged in water supply to inform consumers on the quality of water being supplied, including the TDS level.

These are to be widely disseminated through advertisements and awareness campaigns, besides being mentioned in the utility bills.

The new 'Regulation on Use of Water Purification System (WPS)' mandate that each water purifier will now come with a 'conformance label'--a star rating like label-- declaring its efficiency level as well as water rejection/wastage levels.

The Bureau of Indian Standards is learnt to have developed IS standard (IS 16240: 2015) for drinking water purifying systems which will be technology specific and also detail the acceptable quality of the purified water, besides the recovery efficiency of the machine. At present, purification machines have around 20% water recover efficiency as they are estimated to reject/waste near 70-80% of the water taken in for purification.

The environment ministry--as custodian of green resources--has been pitching for bringing in a more water efficient system in a phased manner, starting with 40-60% efficiency level to reduce wastage.

The RO manufacturer will now have to obtain standard mark/certification under a licence from the BIS on the water purification system.

The regulations also say that the Central Pollution Control Board will soon announce guidelines for management, storage, utilisation and disposal of reject water generated from drinking water purification systems.