Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!cs.utexas.edu!samsung!umich!vela!bbesler
From: bbesler@vela.acs.oakland.edu (Brent Besler)
Newsgroups: sci.electronics
Subject: Re: How does one make a gas (methane) leak detector?
Message-ID: <386@vela.acs.oakland.edu>
Date: 17 Mar 90 21:01:08 GMT
References: <4926@aplcen.apl.jhu.edu>
Reply-To: bbesler@vela.acs.oakland.edu (Brent Besler)
Distribution: usa
Organization: Oakland University, Rochester MI
Lines: 8

I am pretty sure the leak detectors are ionization type.  There is a high 
potential across two plates sufficient to ionize hydrocarbon gases, but not
oxygen or nitrogen.  A current proportional to the HC conc. is passed through
the sensing element.  Similar A/C refrigerant leak detectors exist also.  
Soapy water works pretty well at finding leaks.  You can buy a leak 
detector from a heating and cooling jobber/supply house.

                                          Brent H. Besler