During the webinar on "A water professional’s guide to safe storage', due to time constraint, the speakers could not answer or discuss with all the participants the questions raised. 

If you missed this webinar, please find it here. 

Interesting question from the webinar: what are the safe levels of chlorine in drinking water?

Here is a list of recommendations on the doses by studies and international guidelines:

  1. Lantagne (2008): 2.0mg/L free chlorine for water with turbidity <10 NTU / 4.0mg/L free chlorine for water with turbidity 10-100 NTU. ("these doses are considered suitable for household water treatment to maintain a free chlorine residual of 0.2 mg/l in stored household water treated by chlorination" - Guidelines for drinking water, WHO)
  2. WHO: 5.0 mg/L at the point of distribution
  3. WHO:  Find the dose to reach at least 0.5 mg/L free chlorine residual  at 30 min after dosing (WHO, 2005)

Do you know any other guideline or study? Any regulation on chlorination in effect in your country?