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Author: Subject: Gas masks
franklyn
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[*] posted on 5-5-2009 at 23:18
Really Cheap Gas Masks


How can you go wrong, at these prices you can't afford to be without one.

$ 8.99 each , 3 for $ 24.95
http://www.centerfiresystems.com/GASMASK-FIN.aspx

$ 11.99 each , 3 for $ 29.99
https://www.mainemilitary.com/productcart/pc/viewPrd.asp?idp...
https://www.mainemilitary.com/productcart/pc/viewPrd.asp?idp...


Masks have the virtue of being portable so that fuming procedures
can be done in the great outdoors, or lacking this, on a rooftop.
There is nothing inherently " degradable " about activated charcoal
that imposes a shelf life on a canister providing the seal is intact.
The canisters I received are dated 1987 which predate the mask
by 9 years. Since these were retired together, that should tell you
something of expected service life. Military issued goods are of very
high standard and often discarded in perfectly good condition.
Here is an outline of what the CDC considers in its evaluation of
mask design, and specifications. I doubt the Fins would do any less.
http://www.cdc.gov/niosh/npptl/standardsdev/cbrn/apr/standar...

There is no shortage of people willing to have you pay excessively
for goods of comparable utility with no guarantee that paying much
more gets you anything markedly better suited. Anyway read the
feedback yourself I'm sure there are former servicemen among them
that can critically evaluate their purchase.
http://www.cheaperthandirt.com/MIL1200-1.html

Fit of a mask and how it seals is what matters , as I said before
http://www.sciencemadness.org/talk/viewthread.php?tid=6375#p...
Proper Fit Checks

Positive Pressure Check
Cover the exhalation valve with your hand and exhale gently into the face piece. If a
slight positive pressure is built up inside the face piece without any evidence of
leakage, the fit is satisfactory. This test method is the most widely used to check
proper fit in the field.

Negative Pressure Check
Close off the air inlet valves (i.e., cover the cartridges with your hands), inhale gently
to collapse the facepiece slightly, and hold your breath for 10 seconds. If the
facepiece remains slightly collapsed and no leakage is detected, the respirator fits
properly. It may be difficult to get a good seal when trying to cover the inlet valves
(cartridges).


So why so cheap ?
I omitted to say in the post before that these are discontinued
60 mm canister masks whereas the NATO and commercial standard
is now 40 mm.
http://www.centerfiresystems.com/gasmask-fil.aspx

Small matter you can obtain adapters also.
60mm -> 40mm adapter
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=30031...
40mm canisters and 60mm adapter package deal
https://www.mainemilitary.com/productcart/pc/viewPrd.asp?idc...
https://www.mainemilitary.com/productcart/pc/viewPrd.asp?idc...

These canisters are cheap enough that if one really wants to test
their efficacy its a simple matter to attach one to a vacuum and
draw NOx or Chlorine through it and test for its presence coming
through.
Any canister has a useful service of 6 to 8 hours at a minimum although
recommendation for replacement can be as little as 2 to 4 hours of
exposure to gas contaminants. Assertions that their utility is measured
in minutes invokes concentrations that would dissolve your skin.
Re-use of filter canisters depends on how long you plan to keep one
after its fiirst use. I'd say it should be used within 6 to 8 months after
first use providing it was hermetically resealed in plastic during that
time.
Re-usability study
http://www.osti.gov/bridge/servlets/purl/645463-vrsNgR/webvi...

MIL-1200.jpg - 22kB
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Sauron
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[*] posted on 6-5-2009 at 00:34


I doubt that OS meant an out of date surplus mask with spent AC filters and rubber all shot to hell.



Sic gorgeamus a los subjectatus nunc.
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