How to Fireproof a Safe

Gypsum, Perlite and Vermiculite are naturally occurring minerals and have been used in fire-proofing products for decades. Typically, they are used in a sandwich style construction with other non-combustible products.

We have chosen to use gypsum as the fireproofing mineral in our fireproof safes. Our safes are manufactured with either 4mm or 8mm steel that sandwiches a 16mm layer of gypsum.

Fireproofing layers

Gypsum is non-combustible, which means that it contributes no fuel to a fire. Gypsum can’t help but resist burning.  It's all to do with it's chemical make up.

Calcium sulfate dihydrate — gypsum — traps water molecules within its crystalline matrix. There it remains until exposed to heat higher than 80 degrees Celsius. Gypsum contains about 20 percent water by weight and roughly 50 percent by volume. As it heats up, gypsum begins to release its water as steam, preventing ignition and keeping the opposite side of the gypsum panel cool.

The inside temperature of a fireproof safe during a fire event needs to not exceed 170 degrees Celsius to fully protect your valuables and cash. This level has been established for many years and was based around the ignition point of paper, which is around 233 degrees Celsius. However the advent of polymer banknotes has changed things slightly. While polymer banknotes have an ignition point higher than paper at 375 degrees Celsius, they have a melt point of around 175 degrees Celsius.

So to fully protect polymer banknotes, they should be stored in a heatproof pouch within a fireproof All our fireproof safes come with a heatproof pouch to give your polymer banknotes added protection as standard. Read about our heat reflecting banknote pouches here.

Gypsum is also much heavier than either Vermiculite and Perlite. Adding gypsum as a fireproofing material to a safe adds considerable weight. In the manufacture of safes, extra weight is a good thing. You don’t want a would be thief just to be able to pick your safe up and walk out the door.
Read more about how heavy a safe should be here.

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