To what temperature are fireproof safes, fireproof filing cabinets and fireproof media cabinets tested by UL?

There are different time periods for fireproof testing depending on the UL rating that the product is attempting to reach. The most common ratings are for hour, 1 hour, 2 hour, 3 hour, and 4 hour. As the time goes up so does the temperature to which the product is heated. For hour the product is heated to 1550F, for 1 hour 1700F, 2 hours 1850F, 3 hours 1920F, and 2000F for products rated 4 hours. Once the product reaches the set time and temperature the furnace is turned off. The test product must then cool in the unopened furnace until there is a significant decrease in the internal temperature of the product. This cooling period can take as long as 68 hours and is the point at which most products fail the test due to the fact that the interior of the product continues to rise in the unopened furnace. ... more