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Could a file cabinet be insulated from fire with, say, a fire blanket? Saving money and weight? Answered

File cabinets are increasingly needed by the average Joe in this information age. And fire safe file cabinets are a great protection for hard copy. But they are so expensive and heavy. A 4 drawer will cost at least $1000 and weigh at least 500lbs. I was wondering if anyone has tackled this question.



10 years ago

A proper fire chest (something intended to protect its contents from the typical house fire) is rated "class 350, 1 hour." That means it will withstand 1,700 degrees F for at least one hour without the inside rising about 350 degrees. The full UL test involves more than that -- it includes a specific warm-up profile, and includes dropping the container from a specified height onto an uneven surface to simulate the floor burning through and the container falling through it.

Fire chests achieve this protection by using an insulation which undergoes a slow chemical breakdown, releasing water which boils away to provide cooling.

That's sufficient to protect paper and most optical media. For magnetic media or film, you actually need a much higher rating to provide adequate protection -- they're far more sensitive to heat, and to humidity (which means the interior has to be protected from that active insulation.) The better ones will also prevent water from leaking into the container -- again, the chest will often fall through into the basement, and basements become in-ground swimming pools by the time the firemen are done.

Figure out which documents are CRITICAL and protect those. Anything which is archived elsewhere or can be recreated fairly easily  (eg bank statements) probably doesn't need fire protection. For most individuals, the truly critical documents will fit in less volume than a single file-cabinet drawer -- especially if digitized.

You may want to consider off-site storage  for critical documents, or at least for copies of them, as an alternative to trying to protect a single copy on-site.

The cheap fire chests available under several brand-names really do work, if they carry the UL certification. But _PLEASE_ do not consider them safes, even if they look like safes and have combination locks, unless they also carry UL certification against burglary (which none of the cheap ones will). It is ***MUCH*** harder to build a box that is both secure and fire resistant than to solve either problem by itself; the simplest solution involves essentially putting one set of walls inside the other, which means you pay at least twice as much for the same amount of storage space.

Note that I'm assuming this is for personal use. If for a business, the advice is similar -- figure out what really needs the protection, then pay what it takes to protect it -- but go with higher-quality containers because the value of the contained information is higher and you really want that extra confidence. Talk to a locksmith or safe technician; they can help you find the most cost-effective solution.

Hope that helps.


10 years ago

I think a fire blanket is meant to insulate things that don't normally conduct heat (human flesh vs. metal filing cabinet). Fireproof file cabinets are so heavy because it takes a lot of material to properly isolate the metal from its sensitive contents. A quick test? Wrap some documents (non-valuable) in a fire blanket, and put the fire blanket in a large campfire. Mind you, house fires get notoriously hotter than that...