Chlorine disinfection

rayzzz at rayzzz at
Mon Sep 15 15:33:39 EST 1997

Thanks very much for your answer. Okay, keeping in mind that cysts are more
resistant, what do I do for disinfection? Make the dilution stronger? Allow
it to sit on the surface longer? What would be the ppm in this case? How
long should it remain on the surface before rinsing/wiping?

Also, if there is more bleach to water than the recommended dilution, say
up to 1:4, is the solution less effective? Someone told me that
disinfection depended on ions of chlorine, so that if you had more chlorine
in the water, there were less ions, and therefore less disinfection (I am
very fuzzy on this; I may be recalling incorrectly).

In article <01bcc1e8$c59b6440$142e5ba5 at>, "Alex Castillo"
<castillo at> wrote:

> Now, to answer your question, the dilution you have to prepare will depend
> upon whether you want to treat drinking water or make a disinfectant
> solution. If it is for drinking, you may not want to go beyond 2-5 ppm
> residual chlorine. If it is for preparing a disinfectant, then 100-200 ppm
> will work ok, but keep in mind that bacterial spores and cysts of parasites
> (parasites do not form spores) are more resistant.

Take the zzz out of my address to write to me. 

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