Re: Question about most easily detected volatile organic compound (in 1 ppm)

doug.baer_at_gmail.com
Date: 12/29/04 

Date: 28 Dec 2004 17:09:14 -0800

Los Gatos Research sells a Fast Methane Analyzer for measurements of
methane in ambient air at 10 Hz with ppbv-level sensitivity. Check out
www.LGRinc.com

Tom Scott wrote:
> I'm investigating the feasibility of using the vapor of some organic
> compound for leak detection. Instead of sniffing for He ions as is
> done in vacuum leak checking, the idea is to use diode laser IR
> spectroscopy (or some other simple method) to detect the presence of
> the VOC applied to the other side of a seal under test. This is like
> the detection of trace pollutants in air, but I get to pick my
> "pollutant" to maximize sensitivity and reduce detector cost.
>
> My question is what compound has a vapor that is most easily detected
> by Tunable Diode Laser Absorption Spectroscopy?
>
> The detection compound should be a volatile liquid that is safe, not
> normally in the environment and hopefully orderless (nothing Pepe La
> Pu would like). The detection needs to be fast (< 1 sec) and simple
> (read "cheap") as well. The cheapest TDLs are 780 to 900 nm.
>
> Tom