Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!cbnews!cbnews!military From: amoss@cs.huji.ac.il (Amos Shapira) Newsgroups: sci.military Subject: Re: Gas Masks Message-ID: <1991Feb9.030921.1643@cbnews.att.com> Date: 9 Feb 91 03:09:21 GMT References: <29772@mimsy.umd.edu> Sender: military@cbnews.att.com (William B. Thacker) Organization: AT&T Bell Laboratories Lines: 33 Approved: military@att.att.com From: Amos Shapira In sci.military optilink!cramer@uunet.UU.NET (Clayton Cramer) writes: >open and installed on the mask will destroy the filter. Is it >exposure to the air that does it, or is it flow through the >filter? Would it shorten the lifetime of the filter significantly >to install the filter, but leave the outer seal on the filter >in place? (Therefore, only one seal is open -- the one that >points into the mask). The orders we got with the masks were that once the filter is open there is no use in sealing it, on the conterary: you might forget to remove the seal before using the mask and suffocate to death (it happened here in Israel). The filters are supposed to be usefull for 6 months after openning and 6 hours of actually contacting gas. As long as you don't open them they should be good for several years (don't remember the number) but even then you should do some annual maintanence. You better adopt a simple strategy: DON'T open them until you really fill that you are going to use them. After openning them, DON'T close them but just put them inside a sealed plastic bag. In any case, NEVER let the filter be in contact with water or high humidity. Hope this helps, Amos Shapira Hebrew University, Jerusalem Israel amoss@shuldig.huji.ac.il