Geir Thanks for pointing this out - of course, apologies for the mistyping !
While it will be of no interest to most Forum members I should make it clear that PAS 95 is not a British Standard, and, like many PAS documents, does not command universal respect. Best wishes Stewart On 17 Apr 2012, at 14:20, Geir Jensen wrote: > Stewart, > > As you refer hypoxic air fire prevention, please observe all systems are > normobaric (certainly not hyperbaric) which means pressure is equal to the > barometric pressure at the sea level. Hypoxic air does not change the > barometric pressure (I am disappointed: You know this very well Stew...:). > "Hypoxic air" or "oxygen reduced air" are the two common terms for this > technology. > > Since this thread refers to non-US region, let me inform you hypoxic air > systems are fully covered for design, installation and operation by the > recent specification BSI PAS 95. Currently CEN is developing its own standard > under agreement with ISO. The US communities are is not yet familiar with > fire prevention systems. > > More facts by Wikipedia: > http://en.wikipedia.org/wiki/Hypoxic_air_technology_for_fire_prevention > > Kind regards > > Geir Jensen > Fire Protection Specialist > COWI Fire Int > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Stewart Kidd > Sent: Saturday, April 14, 2012 11:09 AM > To: [email protected] > Subject: Re: Aerosol vs Halocarbon/Inert extinguishing agents > > Reza > > I think I am safe in saying quite categorically that aerosol systems are NOT > suitable for storage areas where the product is paper. Powder would not be > effective in a Class A fire where the fire could be deep seated within stacks > or boxes and where the powder could not react with the flame front. > > Only water or an inserting gas system would be appropriate in such cases - > or, possible an oxygen removal (hyperbaric) system might be suitable. > > Best wishes > > Stewart > On 14 Apr 2012, at 10:05, Reza Esmaeili wrote: > >> Thanks all for the professional replies. >> I am not a professional, but while NFPA 2010 part 5.2.3.2.1 states that "In >> the event of failure of the predischarge alarm and time delay, means shall >> be provided to limit exposure to agents approved for use in normally >> occupied spaces to no longer than 5 minutes." So it is seems to be safe for >> human exposure below 5 minutes while not exceeding the adverse-effect level. >> I agree that Halocarbon/Inert extinguishing agents are the first options, >> but Aerosol can works too. >> >> Before posting this question in the forum, I was thinking that aerosol >> products like Pyrogen are only useful electrical switchboard cupboards or >> small electrical rooms or vessel engine rooms, but now I come to understand >> that although Aerosol is not the best option but where dust or residue is of >> lesser concern, they can be used for even larger rooms in total flooding use >> like pump rooms or paper archive rooms, but they are not suitable for server >> rooms because the residue may harm the hard disks. >> >> Thanks for your nice comments. >> Reza Esmaeili >> Sarian System Novin Co., Ltd. >> www.sarian.ir >> >> >> >> >> --- On Sat, 4/14/12, Thompson, Pat <[email protected]> wrote: >> >> >> From: Thompson, Pat <[email protected]> >> Subject: RE: Aerosol vs Halocarbon/Inert extinguishing agents >> To: "Smith, David L.(FAC)" <[email protected]>, >> [email protected] >> Date: Saturday, April 14, 2012, 2:42 AM >> >> >> Understand that this is my personal take on the subject; as with many >> (most?) posts in the forum the statements made by individuals are >> opinions and should be taken on face value. I say this not to disparage >> the value of the forum; I believe that the collective experience and >> input of the participants is valuable indeed. >> >> I have over 40 years in the fire protection industry and like all >> grey-haired fogies I have seen many things change over the years. For >> instance, there was a time that carbon tetrachloride was listed and >> commonly used in portable extinguishers. Anyone remember NFPA 12B? It >> was the standard for Halon 1211 systems. Again, a product that was >> listed and used in its day that has gone bye-bye. There are more >> examples of products that at their time had a listing (and even their >> own NFPA Standard) that we no longer use. >> >> In my review of these aerosol products what jumps out at me is not what >> they say but what they infer. Nowhere do they state that they are listed >> as safe for human exposure, but the inference is clearly there. Why? - I >> can only surmise that it is because no data exists to substantiate it. >> The only thing they state is that they are 'listed' and then they paint >> a picture that touts their 'advantages' over clean agents. It is a >> dangerous position to make the assumption that 'listed' makes them >> appropriate for a given application. The listing must be examined to >> determine what the product has been tested and 'listed' to do. >> >> Maybe it is a grey-haired characteristic or that I am skeptical by >> nature, but the presentation of information on the websites from the >> proponents of aerosols makes me suspicious. >> >> A video clip of people breathing the aerosol only proves that no >> immediate toxicity is observed; but the inference is safety. Where's the >> testing and data (and/or 'listing') to support human exposure safety? I >> submit it does not exist. BTW- liver damage from carbon tet exposure was >> not immediately evident either. >> >> Bottom line to this old fart is that aerosols may in fact have a place >> in fire protection, but until data is produced and listings established >> for their use in occupied spaces I'll be sticking to the clean agents >> that we have available. >> >> >> >> Pat Thompson >> Special Hazard Sales >> NICET #101475 >> SimplexGrinnell >> A Tyco International Company >> 907-743-9128 direct >> 907-561-4650 fax >> [email protected] >> >> >> -----Original Message----- >> From: Smith, David L.(FAC) [mailto:[email protected]] >> Sent: Thursday, April 12, 2012 3:49 PM >> To: Thompson, Pat; [email protected] >> Subject: Re: Aerosol vs Halocarbon/Inert extinguishing agents >> >> Take s look at WWW.statx.com >> And let us know what you thinks >> >> Sent from my HTC on the Now Network from Sprint! >> >> >> _______________________________________________ >> Sprinklerforum mailing list >> [email protected] >> http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum >> -------------- next part -------------- >> An HTML attachment was scrubbed... >> URL: >> <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20120414/c96c95aa/attachment.html> >> _______________________________________________ >> Sprinklerforum mailing list >> [email protected] >> http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
