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 fire. 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? Thanks! Richard 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.