Each of the clean agent gases have a NOAEL (No Observable Adverse Effect Level) number that they have been tested to. For example, the NOAEL % for Novec 1230 is 10%, (this means that they have exposed an animal to that concentration with no observable adverse effects) and the design concentration for Class A Hazards is 4.2%.
FM-200 has a 9% NOAEL and approximately a 7% design concentration for Class A Hazards. So, the safety margin is not as wide and so there is less flexibility when adding cabinets etc. that would change the volume and consequently change the concentration. Reza is right to be concerned about personnel occupying an area during discharge. I have heard of applications where the personnel are required to stay in the space during discharge and the design of the clean agent system needs to allow for that possibility. I would talk to an FM-200 supplier who does the actual design to find out what they include in the volume calculations. Personally, I was told to not include the volume of server racks etc., but I would be inclined to include the volume of the cabinets depending how easily the gas can get in and fill the volume. Reed A. Roisum, CET Fire Protection Technician Ulteig Engineers, Inc. 3350 38th Avenue South Fargo, ND 58104-7079 Direct Number: 701.280.8580 Mobile: 701.212.8810 Main Office: 701.280.8500 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Reza Esmaeili Sent: Wednesday, September 03, 2008 1:06 PM To: [email protected] Subject: RE: FM-200 enclosure volume (Exclude Cabinets volume?) Thom, What makes me worry is that we say FM-200 gas is safe for occupied spaces & will not affect the personnels in the computer room. Imagin that the volume of cabinets is about 25% of total volume, so if my design concentration is 7.4% then the real concentration is 9.25%. I agree that cabinets are not "Gas Tight" and will become filled with the FM200 just at a slower rate, but it takes time, may be for 2 minutes, then can we still say this gas is safe while the personnels may be subjected to 9.62% even at the first 2 minutes of gas release? Thanks, Reza Short answer NO! The cabinets are not "Gas Tight" and will become filled with the FM200 just at a slower rate, than the rest of the room. Thom McMahon, SET Firetech, Inc. 2560 Copper Ridge Dr P.O. Box 882136 Steamboat Springs, CO 80488 Tel: _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [EMAIL PROTECTED] To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [EMAIL PROTECTED] To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
