[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Explosive detectors



I posted some information yesterday regarding IMS type explosive detectors 
without giving the whole story so here goes.  Warm air is blown by the 
person, this causes the contaminants to be released. The air is then drawn 
into the IMS  where the radioactive source ionizes it.  It is the 
accelerated down a heated drift tube onto a Farady plate detectors where the 
output is given in voltage and current.  This is relative to the time it 
took to accelerate that particular ion through he drift tube.  The time is 
indicative of the molecule size and is repeatable.  So as long as you have a 
baseline measurement of the molecule you are looking for at the barometric 
pressure and humidity you are working in you can analyze for almost 
anything.  Another sample collection method is a small vacuum with a sample 
filter attached to it .  The filter is analyzed the same way as above.

Kim Merritt, RRPT
Sandia Labs
kdmerri@sandia.gov

Standard disclaimers apply.