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Installing Halon Fire Supression System at Home?
swmagazine asks: "The house my family is building just burn down 2 weeks before competition. Now that the insurance is paying out some money, I am seriously considering installing Halon system at home because the house comes with a server room and I will be having at least 10 computers running in the house. I would like to know if anyone has experience with Halon system as well as the feasibility of installing such system at home." The possibility that your computer could conceivably be a fire hazard is extremely low on newer machines. Older machines, without the proper protection, may overheat, and that might cause problems. Might such a system minimize the damage posed by a house-fire, or are they too expensive (or too ineffective) for the average home owner?
Well since no one, that I know of, makes ozone depleting Halon anymore, you may want to look at an FM-200 system. I still think this is a bit excessive for home use, most systems I've seen are more than >$10k after purchase and installation.
halon is un-breathable. this means that if someone is in the house when the system releases its gas, that that person/animal is dead. it starves the air of oxygen.
I wouldn't do it.
the best prevention is to simply watch what the heck is going on with all the electrical stuff in your house and to simply not be careless. sure, all fires aren't preventable, but 99.999% are. Insurance and a good data backup solution will take care of the rest.
Consider the ordinary building sprinkler system. There's a reason you can't put up a new public building without one: they're damned effective. But they're also expensive. I don't think I've ever heard of them in a single-family structure.
Ok, you can no longer (I'm assuming you're in the USA) get halon, as it is harmful to the ozone layer. What's now used for this purpose is called Inergen. Furthermore, despite all the howling by everyone about the risk of suffocation, keep in mind that it will take a bit of time for an entire home to become filled with the stuff, and the fact that any professionally installed system includes alerts to let you know when the system is activated. Between the warning you get, the air in your lungs and the air that has not been displaced yet, you can be just fine. This kind of system has been put in many types of facilities in all sorts of different ways, and unless it's done incredibly wrong, by no means will it turn your home into a big gas chamber :)
For your security, this post has been encrypted with ROT-13, twice.
http://www.healthsafetyinfo.com/news/tip/autotip-a rc.cfm?content_id=11890
It's old. The more humans I meet, the more I like my cats. At least they are honest.
In a great many jurisdictions, Halon systems are not permitted in personal residences. They are a hazard to life and limb. The old server rooms we protected with Halon systems required 'life support' equipment in case you were in the server room when the system discharged.
Halon displaces the oxygen in the environment it is released into. This is NOT something you want to be doing in your house without sufficient research, and compliance with ALL local ordinances. Failure to do this could jeopardize you and your family. However, I'm sure your machines would survive.
Your insurance company would likely be less than thrilled at the prospect of you having an automated mechanism for discharging a gas that can asphyxiate you and yours.
I love it.
Halon is -
A trade name for a class of halogenated alkanes. Other trade names for these materials are Freon and Genetron. It is one of the classes of materials that has been proven to attack the ozone layer, with persistance in the atmosphere measured it decades. Manufacture of many types of Halon was banned by the Montreal protocol in 1987. Further legal restrictions were subject of the later Kyoto protocol.
The particular Halons used in fire extinguishment applications are 1301 and 1211. As of Jan 1 2003 refilling existing halon systems is banned in most of the world, and dismantling of all Halon fire extinguishing systems (including safe disposal of their contents) is required by Dec 31 2003.
Halon works by displacing the natural atmosphere in a room, reducing the concentration of oxygen to levels below that which will support combustion. Since the human body metabolizes sugars to sustain life by a controlled form of combustion, human metabolism will cease under the same conditions.
Halon, when exposed to fire or similar high temperature conditions will decompose into a variety of toxic gases that will generally cause traumas such as pulmanory edema.
It is illegal to install new Halon systems except in certain 'Critical' applications, mostly in aircraft fire supression systems.
For home applications involving electrical systems a good ABC fire extinguisher containing a dry chemical like monoammonium phosphate available at your local hardware store is the best choice. Use of fire resistant materials, elimination of clutter and especially adherance to electrical codes in your server room are also recommended to prevent fires in the first place.
Your most important fire control steps are prevention.
I was quoted $1.25 per sq ft several years ago. Even if prices have gone up to $2 sq ft, that's only 1 or 2 percent of the total cost. Pretty cheap for good protection.
Also, the very fact that you are thinking of Halon implies you want to put the fire out and preserve everything. That's a nice goal, but computers are cheap and easily replaced, and presumably you have offsite backup storage.
The point of fire protection is to give occupants time to get out and to stop the fire from spreading. Saving the structure itself is a nice side benefit. Saving minor contents is pure gravy.
Infuriate left and right
Actually, this is common sense. If you wanted to damp combustion by excluding oxygen, it would be cheaper (and more environmentally friendly) to use an inert gas like nitrogen or carbon dioxide.
There is no doubt that Halon does replace oxygen to some degree and therefore does present a potential danger of asphyxia. However, there is another problem with Halons. When they come into contact with a fire, they breaks down, releasing breakdown products that are extremely dangerous, even at low concentrations.
"The house my family is building just burn down 2 weeks before competition." Was that before or after completion?
Repeal the DMCA!
Search Google for Argonite and you will find such great links as this one. Transcript below for the clicking-impaired or just lazy :-)
Argonite - fighting fires nature's way
More and more companies are today ensuring that environmental considerations play a major part when selecting a fire fighting system. So much so that Argonite, which consists entirely of naturally occurring gasses, has long been the solution of first choice for many industrial and commercial building occupiers.
Not only has Argonite zero Ozone Depleting Potential (ODP), it also contributes nothing towards global warming, thanks to a complete absence of hydrofluorocarbons-HFCs. At the same it is a gaseous fire suppressant that has an enviable 50-year track record.
The environmental answer:
Argonite is a leading environmentally-friendly replacement for Halon 1301. An equal blend of nitrogen and argon, it produces no secondary combustion products and is particularly suitable for fighting fires in confined spaces. Because its molecular weight is close to that of air, it lingers longer when discharged to extinguish a fire. This reduces the need for hermetic sealing of a protected room - a process that can be very expensive and needs to be repeated every time structural changes are made.
Argonite is not prone to fogging, is non-toxic, non-corrosive, leaves no residue and is electrically non-conductive. This has led to it being successfully specified in applications where there is a need to avoid secondary damage by the fire fighting agent. Popular applications include computer and control rooms, tape and archive stores, electrical cabinets and switchgear compartments and around telecommunications equipment.
How Argonite Works
Should a fire start, Argonite is injected rapidly into the room, reducing the oxygen level from the normal 21% to between 11% and 13%. This is too low for further combustion to take place, yet high enough to allow essential safety personnel to operate.
Argonite is suited to either total flooding or local application. When more than a single room or compartment is protected, GIELLE normally recommends that a central bank of Argonite cylinders is connected via diverter valves. This frequently proves to be the most cost effective and efficient solution. As a permanent gas working under high pressure with single-phase flow characteristics, complicated pipe networks can be installed.
Halon is bad for the ozone layer was the reason given for its going out of use in the US. They have found out recently that it is not as bad as they though so it is starting to come back.
Being exposed to Halon is not a big deal. The OSHA exposure standard is based on exposure to Halon in a neutral environment. Being in the room with a halide gas and a large fire is the problem.
The major health risk with Halon dump extinguishers is the by products of the quenching cycle. The way halides interfere with combustion is an ionic cycle that sucks the energy out of the combustion process. The cycle is a true cycle and depends on the halides eventually returning to their original state. During the cycle you get other unstable intermediate products that are not toxic per say. They are ionicly unstable and will rip atoms out of stable molecules to get to a stable state. The hotter the fire the more of the intermediate products produce and the longer they hang around. Additionally the cycle is not 100% closed. The combustion products from the plastics in computers plus the halide gases make some bad stuff(TM) like phosgene for example.
A small fire goes out quickly, typically >30 seconds and produce little in the way of toxic by products. A big fire goes out more slowly, 3-5 minutes. Because larger fire is hotter and takes so much more time to quench, far more of the toxic by products are produced. Breathing the larger quantities of the intermediate products created by a larger fire plus toxic gas produced by the fire can cause irreparable harm to you lungs. Getting out of the room quickly is to avoid exposure to the smoke and letting the Halon do its job.
The SOP for Halon dumps was: you pull the handle the electric primary power to the room disconnects, a horn sounds, a short time, seconds, later the Halon floods the room. The delay is to let everyone leave before the flood starts. Once the fire is out and the Halon and combustion site has a chance to cool off you only have to worry about the toxic smoke from the fire. I've seen people open the door to soon after a fire, let too much of the Halon escape and have the fire rekindle.