Richard :
Can't really help with safe design, but assuming you are wanting to store
papers, have you looked into computer media fire safes ? Although the
cheap ones are still only rated to 1/2 hour, that includes keeping the
interior below 125F. Since paper is supposedly 'safe' to about 350F, it's
reasonable to assume that a media safe will protect paper for many times
it's rated protection time.
The UL ratings are also pretty conservative. You might want to double
check your fire statistics, since "at heat" is considerably different than
"peak temperature". Fire safes are primarily sensitive to temperature
times time, and the UL test includes not only the rated interval at a
continuous exterior temperature of 1550F, but a "cool down" interval
afterwards where the temperature is allowed to slowly fall to room temp.
IOW a fire safe with a 1/2 hour 1550F UL rating may well protect it's
contents in a fire that peaks at 1800F and remains over 1000F for 45
minutes. YMMV of course.
Which brings up another point : how are you going to test your homebrew
safe ? The only way to be sure of your efforts is to build two of them,
then test one. By the time you go through all that hassle (just how are
you going to build a 2000F fire ?), and consider what happens if you are
wrong, it might be better to just buy a safe with the rating you want. For
example, in just a few minutes searching, I found a Sentry A3431
home/office 1 cuft fire-safe, with a 2 hour rating and a $30,000 guarantee,
for $195. (See http://www.office1000.com/supplies/sentry.html , NFI, etc.)
Randall
On Friday, July 21, 2000 8:53 AM, Richard George [SMTP:rkg@teleport.com]
wrote:
>
> Hi,
>
> I was considering the purchase of a fireproof safe, but I find that most
of the more reasonably priced
> ones have inadequate fire ratings (a lot of them gloat about a 1/2 hour
rating, but I found that the
> average fire in my area burns at heat for 45 minutes, at a temperature
higher than a lot of them are
> rated for).
>
> It was suggested that one could simply purchase one of these safes and
add additional lining to
> increase their fire rating.
>
> I was wondering if there are any "safe gurus" out there who might have
some input on doing
> such a thing. I've seen a lot of safe sites online, but there doesn't
seem to be much out there
> on safe construction - does anybody have any good pointers to information
on this topic?
>
> As an aside, somebody pointed out that my concerns about a potential
thief using my plasma
> cutter or torch to get into the safe can be greatly reduced by putting
the plasma cutter consumables
> and cutting torch tips in the safe....
>
> Thanks in advance,
>
> rkg
> (Richard George)
>
|