Re: SB: alt Low cost water> uv sterilizer

[Sherwood Botsford <sbotsford@sjsa.ab.ca>]

On Thursday 29 August 2002 02:14 pm, Charmaine R Taylor wrote:
: A really low cost way to purify/sanitize water is to use a
: glass jar, with metal lid- aka Mason jar- and solar cook
: it...it does not have to boil to be safe, only 140 deg for a
: few minutes. (  just 1 min I believe)...the
: www.solarcooking.org site has a lot of info.  they  have a
: cool device at Solar Cookers Intl in Sac, a WAPI, water purity
: indicator, a small  SEALED wax pellet that  only melts once
: 140 deg+  is reach, and is reusable...$5.00 each,  and I've
: used these to  make safe water.
:

I disagree.  There are good reasons when sanitation alerts go out
that the word is 'boil water for 10 minutes.'   Our dishwasher 
(school cafeteria) is required to cycle for 30 seconds at 185 F.


However if 140 degrees kills 90% of the common bugs, it may make 
a health difference.  It's certainly better than nothing.

A better way may be to get quartz jars.  There are commercial UV 
sterilizers that have a bright UV lamp and a quartz tube.  Both 
inside a mirrored tube.  The light is not enough to appreciably 
warm up the water, but kills six nines of the bugs (99.9999%)

I would think that this could be adapted to work with a trough 
solar reflector, and pairs of buckets and some tubing and could
provide clean water for a neighbor hood group of vilages.


:
: ---
-- 
Sherwood Botsford				1-780-848-2881 Ext 134
St. John's School of Alberta			RR - 5 Stony Plain, Alberta TZ7 
1X5
Alternate address sgbotsford@yahoo . com

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