It was pointed out to NLM by fire safety engineer Nick Artim (of the Fire
Safety Network) that a gas fire suppression agent provides a "single
discharge ... If the gas fails to suppress the fire with the initial
discharge, then fire control will not be accomplished."  Based on this
information, I would assume that the logic for Culpeper is to have a wet
pipe backup system ready to go in the event a fire is not completely
extinguished by the gas.  It would be interesting to learn how the wet pipe
system will be activated in the event the gas system fails to extinguish the

When the National Library of Medicine had an old CO2 system removed, we
opted for a wet pipe system to replace it, but more importantly put strong
emphasis on upgrading the detection system.  We had a high sensitivity
air-aspirating detection system installed and connected to the main campus
alarm system.  Since there is a fire department on the NIH campus, we know
we have very fast response time.  Our strategy is to combine the early
detection capability of an air-aspirating system with proven quick NIH fire
department response time, so that we can locate and eliminate a fire source
before it reaches a stage that would activate the sprinkler system.

I have copied this message with thanks in advance to Mr. Artim, who may also
want to add to these comments (since they will undoubtedly look quite
familiar to him).

- Walter Cybulski
National Library of Medicine

-----Original Message-----
From: Richard L. Hess [mailto:[log in to unmask]]
Sent: Wednesday, February 18, 2004 11:33 PM
To: [log in to unmask]
Subject: Re: [ARSCLIST] fire suppression systems

Hello, Gregory,

I'm surprised that the backup system is wet pipe rather than dry pipe
pre-action?  May I ask why?



At 06:28 PM 2/18/2004 -0500, you wrote:
>Hannah - For the Library of Congress' main new collections storage
>facility at the National Audio-Visual Conservation Center in Culpeper,
>Virginia, we are utilizing a layered dual-system fire protection
>approach, with an FM200 gas-based system as the initial primary
>suppression agent back up by a wet-pipe sprinkler system.