Hydraid BioSand, Руководство по установке

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money can fund a portion of the filter and/or be returned to the
water committee and used for community needs or to compen-
sate the facilitator or committee.
4. See Appendix 1 for sample forms for installation and monitoring
via a household survey.
Frequently Asked Questions
1. Can the Hydraid
®
BioSand filter kill all viruses and bacteria?
No, it is never correct to say the Hydraid
®
BioSand filter kills all
viruses and bacteria. The Hydraid
®
BioSand Water Filter removes
98-9% of viruses and bacteria with a fully developed biolayer and
has been shown to reduce diarrhea by 47-59%.
2. Can the Hydraid
®
BioSand filter remove parasites?
Yes, typically 98.9% of parasites are removed if the filter is
installed and used correctly. It is important to note that the
majority of parasites are highly resistant to disinfection with
chlorine; therefore, the best way to remove parasites from water
is to filter it.
3. Can the Hydraid
®
BioSand filter remove earth or dirt
in water?
Yes, the filter removes most solids or turbidity in water. It is de-
signed to handle turbidity in the normal course of operation. If the
water is very dirty (more than 70–100 Units of Turbidity [UOT]),
follow the de-sedimentation processes described in the Usage of
the Filter, Week Three and After section on page 8. If the water
is very, very dirty, an additional, final de-sedimentation process
of pouring pre-filter water through a finely woven fabric, doubled
several times, is recommended to remove the majority of the dirt
before pouring the water into the filter. Additionally, the filter may
need to be cleaned more frequently.
4. Why should I add chlorine to the post-filtered, clean water?
Isn’t filtering alone or chlorination alone enough?
The filter removes most of the harmful parasites, bacteria and
viruses in the water with a fully formed biolayer, but not all. Peo-
ple with deficient immune systems and especially children under
5 years of age, could still become ill. Filtration and chlorination
are complementary. The addition of chlorine to the filtered water
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