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Halo Fire Supression Ventilation Question

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gabber4858

Computer
Jan 22, 2010
3
We have a halo system in our computer room. I just found out today that maintenance plans on permanently sealing the mechanical vents shut. Is this safe to do? I thought there was a reason for the vents and the forced air ducts in the room specifically for the Halon system. This is an old system that has been grandfathered in. Any advice is appreciated, or a specific document stating this is ok would give me piece of mind.
 
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suggest you have a fire extinguishing company that deals with this type system evaluate the entire system to include the ventilation system to see if what they want to do is correct.

or hire a fire protection engineer to evaluate what they want to do
 
Have you been given a reason for sealing the vents? Is your system being serviced on a regular basis by a qualified company with qualified techs?
 
The main reason I was given was they did not want us to be able to hear the department's conversations that sit on the other side of the vents. CDAFD, you have a good point, I should check with the company that inspects the system.

I know the vents are there for the halon system. Pretty sure they close, to get the right amount of halon saturation to be effective in smothering the fire. But if they vents were not needed for another reason, why were they installed? Could have just left the wall alone.

Thanks Cdafd, and Fireguy! I will ask the maintenace guys if they got the ok from the Fire Company we use.
 
Once the fire is out, wouldn't you want to ventilate the room before entering?
 
Chicopee,

That is my core fear. Like I said, I thoght there was a reason for the vents. I was hoping to find someone that has an old NFPA rule for the ventilation. I only have a NFPA 13 book and never delt with chemical supression before. I hope to find out more tomorrow. THANKS EVERYONE!
 
Halon is completely safe as long as the system was installed properly (i.e. proper concentration for the given room size). In other words, there is no need to "vent" the room prior to entering. Halon is safe for human occupancy as long as the concentration is within the intended specifications................the reason halon has been banned is due to the EPA (they claim that halon damages the ozone when discharged into the earth's atmosphere).

Inergen and FM200 are the two most common replacement gaseous extinguishing agents for halon........ALL three of these gaseous extinguishing agents are intended to protect rooms where humans might be present (i.e. if humans are trapped or unconcious in the room) without posing any health hazards to the trapped people. I am only writing this resonse because way too many people think Halon is deadly (like some other extinguishing agents). One more important point that so many seem to miss is that these three gaseous agents are NOT intended for and are NOT effective against "seated" fires involving ordinary combustibles.

My response regarding the actual question in the original post is to find a qualified FPE and make sure you are not creating a serious problem with the proposed changes. I have not evaluated you situation; however, in general permanently closed HVAC vents will more than likely not present a problem. If the wall was solid there would be no problem..................HVAC vents have automatic dampers to prevent the loss of halon concentration; permanent closure would still satisfy this requirement. I write these words, but from a legal standpoint, you really should not consider making any changes without involving a qualified engineer in the process (what if smething happens and the halon system is ineffective.........you could find yourself in court and the potential consequences could be very severe if there is a death!!). Just a little food for thought.
 
The vent could be part of the ventalation system that is shared by many rooms, and like you say when the system goes off it does shut to seal the room.


Tell them to move thier top secret meetings to another room
 
I don't know what agent is being used in this case, however, much older systems using Halon 2402 would have necessitated a ventilation system since Halon 2402 is highly toxic and is no longer recognized by NFPA. In addition at the onset of a fire a certain amount of carbon monoxide and dioxide in addition to the products of combustion of plastics would also have to be ventilated.
 
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