I am working in a laboratory whose main focus is in water treatment and supply of potable water to a township. We are following BIS norms for maintaining the water quality as per IS 10500 and also following IS method for taking water samples.

My question : Is there any BIS or IS specification which can guide me how many numbers of samples should be taken from consumer's tap catered by surface water treatment plant?

I know there is a population slab and the numbers of samples depend on it and the suitable number is known to me from a book of Indian water Works, but I would like to know the IS specification where the population slab and its related sample taking numbers are mentioned.

Subhabrata Banerjee
bsubhabrata@hotmail.com