NFPA 2001 does not require a purge system. It is sometimes provided as a convenience for getting the protected area back into service. The alternative is a manual purge, typically via large industrial fans. If the FD initiates this type of purge, you could have a big problem with data center uptime if there is a need to maintain continuous cooling during or immediately after discharge. In that instance, you may want to have in place a smaller system that exhausts gas incrementally, allowing the CRAC units to maintain cooling. As always, the value for this type of purge system depends upon whether a redundant facility is available, or how critical uptime is for the owner.
Ray Schmid, P.E. Schmid and Associates Fire Protection Engineers -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Allan Seidel Sent: Sunday, March 30, 2008 12:32 AM To: [email protected] Subject: Re: Purge fan Usually not but there are instances where one would be advised. The gas is denser than air. In an installation on the ground floor or higher, the gas would flow out of the room when the entrance door is open. If the room is small compared to the rest of the building or if there happens to be a direct path to the outside, an exit stairwell for example, then the gas will quickly dilute or quickly exit the building. But say you had an outrageously huge installation three floor levels tall where the bottom floor is below grade and the upper two levels are open grate steel flooring. There is no way for the gas to flow out at the basement level. In fact it would flow out of the protected area and end up flooding the remainder of the basement, which for this reason by the way would not be a good location for the control panel. Another example might be a tall concrete vault apparatus room built with the bottom half below grade. The exhaust system should have some of its ducts picking up air near the vault floor. Keep in mind that there may be more in the air than agent that needs to be cleared out. The sooner the air is clear the sooner the detection system can go back on line and the sooner the fire department will comfortable to allow occupancy. Allan Seidel St. Louis, MO On Mar 29, 2008, at 2:30 AM, Haji, Jaber M wrote: > A room is protected by Novec 1230 gas suppression system, dose it > require a purge fan? Keep in mind that this it shall comply with > NFPA 2001 or any other recognized standards. > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > To Unsubscribe, send an email to:Sprinklerforum- > [EMAIL PROTECTED] > (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
