In independent underwriters laboratory tests, Fire-Safe products are subjected to fire for 1/2, 1 or 2 hours. For a product to earn a UL classification, the documents stored inside must remain completely undamaged.
UL Fire Endurance Test - After heat sensors and paper are placed inside the safe, the unit is locked and exposed to a uniformly distributed fire. The furnace is regulated to reach a maximum temperature of 926°C for a period of one hour, or 1010°C for two hours, then allowed to cool without opening the furnace. The interior temperature is recorded throughout the test and during the cooling period until a definite drop is shown and must never exceed 176°C. Once cooled, the unit is opened and examined for usability. The units locking mechanisms and parts fastenings are examined for security and the interior examined for visible evidence of undue heat transmission
UL Fire-Impact Test - The UL Impact Test calls for the safe to be heated to 843°C for 30 minutes (892°C for a 2 hour fire rated safe) then dropped onto concrete rubble from a height of 30 feet. The safe is then turned upside down and reheated for another 30 minutes (45 minutes for a 2 hour fire rated safe). During this process, it must maintain its integrity and protect all contents in order to pass the UL impact test.
UL Explosion Hazard Test - The safe is locked and placed into a furnace preheated to 1093°C. This temperature is maintained for 30 minutes (2 hour test is 45 minutes) and if no explosion results, the unit is allowed to cool without opening the furnace doors. Once cooled, the unit is opened and examined for usability. The units locking mechanisms and parts fastenings are examined for security and the interior examined for visible evidence of undue heat transmission. If the safe is not constructed properly, the rapid heating will likely cause an explosion.
Fire Impact Test (Manufacturer’s Option) - After the explosion hazard test the safe is removed from the furnace and within two minutes is dropped 30' onto a riprap of brick on a heavy concrete base. After impact the unit is examined for deformation, rupture of parts, damaged insulation and any other openings into the interior of the unit. Once cooled, the unit is inverted and reheated to 843°C for a period of 30 min. (2 hour test: 45 min. at 843°C). Once cooled, the unit is opened and examined for usability. The units locking mechanisms and parts fastenings are examined for security and the interior examined for visible evidence of undue heat transmission.
Cool Down Test - This procedure is a key part of UL's fire testing procedures. After a one or two hour fire rating test, the safe is left in the oven for cool down time with the heat turned off. Because of the intensive heat of one and two hour tests, the temperature inside the safe will continue to rise for up to one hour after the oven is turned off. To pass UL testing, the safe's interior temperature may not exceed 176°C at any time during heat up or cool down procedures.
UL Labels Explained
FR - Fire resistant, un-rated insulated safe - This product is awaiting UL approval.
Class 350 1/2 Hour Fire Rating - During this test, the safe is heated for one half hour to reach an exterior temperature of 843°C. Because paper will begin to char at approximately 204°C, the unit being tested must maintain an interior temperature of less than 176°C during heat up and cool down testing in order to earn its rating.
Class 350 1 Hour Fire Rating - To earn this rating, the safe is heated for one hour to reach an exterior temperature of 843°C, then put through the cool down test. During this time the safe must maintain an interior temperature of less than 176°C.
Class 350 1 Hour Fire & Impact Label - The safe has passed both UL impact testing and Class 350 1 hour fire testing (see above).
Class 350 2 Hour Fire Rating - The safe is heated for two hours to reach an exterior temperature of 843°C and must maintain an interior temperature of less than 176°C to earn this rating.
Class 350 2 Hour Rating and Impact Label - The safe has passed both UL impact testing and Class 350 2 hour fire testing (see above).
