flashing ductile iron pipe???? 2

[vnistra800]

hi friends :

i have got ductile pipe new network system and i want flashing this system by calcium hypochlorite to kill bacteria .

how much concentration of hypochlorite i must used without effect of pipe material and for what period of time ????
any articles will be appressiate.


i am gratefull for anyone help me

best regrds

 

[ccor]

From memory AWWA C651, "Disinfecting Water Mains" requires a 24-hour period where the Free Chlorine concentration must be at least 25mg/l at the start and no less than 10 mg/l after the 24-hour period. It also requires two P/A coliform tests.