The Best Ratings for Fire Safes

Temperature Rating

• The most important feature of a fire safe is the maximum temperature rating. The rating indicates the maximum temperature inside the safe during a typical fire. Standard fire safes have a maximum temperature rating of 350 degrees, which is cool enough to keep money, documents and other papers from burning. The next-best rating is 150 degrees. This temperature is cool enough to protect magnetic tapes, CDs, DVDs, photographic film, photographs and paper. The best rating for a fire safe is 125 degrees. These safes are designed to protect floppy disks, microfiche and stamp collections. Safes rated at 125 degrees also have seals that protect against water damage.

Endurance Rating

• Along with the temperature rating, fire safes will have an endurance rating. The endurance rating specifies how long a safe can endure a fire before exceeding its temperature rating. Some smaller safes have a half-hour rating, but most residential fire safes carry a rating of one, two or three hours. The best safes have a rating of four hours. These are mainly used at businesses and institutions to store valuable records.

Explosion Hazard Test

• Many fire safes also are tested to see how well they resist the sudden increase in temperatures associated with explosions. All safes rated by UL as Class A, B or C pass this test. The test safes are inserted into a furnace preheated to 2,000 degrees. They are left in for 20 minutes to see if the sudden increase in temperature ruptures the safe walls.

Fire Impact Test

• Fire safes also are rated according to whether they can withstand a fall from a second or third story during a fire. All UL-approved fire safes are tested in this manner. The safes are heated then dropped 30 feet onto a pile of bricks to see if they maintain integrity. Other testing companies conduct similar tests, although the height used in the tests may vary.