Gun Safe Fire Ratings

How to tell if a safe can take the heat A typical house fire lasts for 27 minutes and burns at a temperature of 1100 degrees Fahrenheit. A standard fire-resistant gun safe will offer 30 minutes of fire resistance at 1200 degrees Fahrenheit. Even with the quick response times of the brave men and women in our nation's firefighting crews, a three-minute differential could be cutting it pretty close, especially if you're also storing more sensitive items in your safe, such as computer disks. For that reason, many people choose to buy gun safes that offer fire resistance not only for longer periods of time, but also at higher temperatures. When shopping for fire-resistant gun safes it's important to consider which rating system is being used by the manufacturer. Some manufacturers offer their own rating, while others receive certified ratings from recognized third-party product safety testing organizations. One of the leading third-party examples is Underwriters' Laboratories (UL), a privately owned and OSHA-approved testing and certification organization that has over 80 years of experience with testing and certifying safes. UL is regarded as one of the world's leading product safety certifiers.

UL's ratings for fire-resistant gun safes are grouped into three classes: Class 125, Class 150, and Class 350. The numbers of these classes correspond directly to a safe's fire resistance. For example, a Class 125 safe exposed to external temperatures of over 1700 degrees Fahrenheit will maintain an internal temperature of 125 degrees F. However, it won't do so indefinitely. Each UL class rating is accompanied by an hour rating. Thus a UL Class 350 2-hour safe will maintain that internal temperature for at least two hours in 1700 degrees Fahrenheit heat.

UL also performs explosion hazard and fire impact testing on safes ("impact testing" means heating a safe to 1550 degrees F and then dropping it from a height of 30 feet onto brick and concrete).

Two other prominent safe testing and certification organizations are Intertek ETL Semko and Mercury Fire Protection. ETL's ratings are time- and temperature-specific. Mercury's ratings are divided into Class I, Class II, and Class III, as detailed below.

Mercury Class I: internal temperature of 350 degrees F for 45 minutes at heat of 1200 degrees F

Mercury Class II: internal temperature of 350 degrees F for 60 minutes at heat of 1275 degrees F

Mercury Class III: internal temperature of 350 degrees F for 120 minutes at heat of 1550 degrees F