Ten Things You Didn’t Know About UL’s Safe Testing
- The best safecrackers in the business never steal a penny. They work for UL.
- UL has been testing and certifying safes for more than 80 years. The first safe tested for burglary resistance was in 1923 and the first bank vault in 1925.
- Chisels, wenches, screwdrivers, power saws, cutting torches, crowbars, abrasive cutting wheels, jackhammers, even specified amounts of nitroglycerin are just a few of the “tools” UL technicians use during a safe attack. The idea is to test safes to worst-case scenarios. They use tools that could be found at any construction site or hardware store. They also analyze blueprints as if the burglar might have blueprints of the design and attack its weakest points to evaluate the safe for certification.
- UL’s safe attack tests are conducted by a two-person crew. The object is to create an opening large enough to withdraw “valuables” (anywhere from 2- to 6-square-inches on a safe and up to 96-square-inches on a vault), activate the locking mechanism so the door opens or to cut as many bolts from the door as necessary to pry it open before the time specified in the rating requirement expires.
- Safes are rated for their resistance to attack against specific tools for a set period of time. There are a dozen different ratings, everything from ATM machines, to gun safes to bank vaults. For example, a safe that bears a Class TRTL-15×6 rating, which might be found in a jewelry store, should resist a hand tool and torch attack for a minimum of 15 minutes. A TRTL-30×6-rated safe, which would protect important documents or store money, should withstand an attack for 30 minutes. The ultimate safe rating (a TXTL60) should withstand an hour’s worth of attack that includes the use of 8 ounces of nitroglycerin.
- Because of the size and weight of certain safes and vault doors, it is not always practical to have the product shipped to UL’s laboratory locations. UL’s burglary protection staff has traveled to destinations such as Japan, France, Israel, England, Finland, Taiwan and India.
- In addition to burglary protection ratings, UL also rates safes for their fire resistance protection. Class 350 safes protect paper documents, Class 150 safes protect magnetic tape and photographic film, while Class 125 safes protect floppy disks. In addition to the Class Rating, safes obtain an hourly rating for fire resistance anywhere from 30 minutes to four hours.
- Another cool test UL runs on safes is an impact test. This test simulates a safe falling though multiple stories of a building resulting from a fire that has weakened the structure. After the safe is heated to 2,000 degrees Fahrenheit in a furnace, it’s raised three stories and dropped onto a pile of bricks. In order to meet the requirement, the safe can’t pop open. Temperatures inside can’t rise to above 300 degrees Fahrenheit and sample papers left inside have to be readable.
- The specialized suits you sometimes find technicians wearing are not just for show. Their entire ensemble, including protective coat, helmet and gloves, protects the crew against the adverse effects of sparking. After all, safety can’t be taken for granted, even within the walls of UL.
- Safes are just one of the 19,000 product categories that UL tests and certifies. While UL’s burglary protection team cracks combinations, shatters glass and fires .44-caliber bullets at body armor, other UL engineers and technicians keep busy testing everything from TVs, coffee makers and holiday light strings to fire extinguishers, medical CAT scan equipment and building materials.
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U.L. Burglary Rating Classification
Signifies a combination-locked safe designed to offer a limited degree of protection against attack by common mechanical and electrical hand tools and any combination of these means.
- U.L. listed Group II, 1 or 1R combination lock.
- 750 lbs. minimum or comes with instructions for anchoring in a larger safe, concrete blocks or on the premises where used.
- Body walls of material equivalent to at least 1″ open hearth steel with a minimum tensile strength of 50,000 P.S.I.
- Walls fastened in a manner equivalent to continuous 1/4″ penetration weld of open hearth steel with minimum tensile
strength of 50,000 P.S.I.
- One hole 1/4″ or less, to accommodate electrical conductors arranged to have no direct view of the door or locking mechanism.
Successfully resist entry* for a net working time of 15 minutes when attacked with common hand tools, picking tools, mechanical or portable electric tools, grinding points, carbide drills and pressure applying devices or mechanisms.
U.L. Label Burglary Classification
Signifies a combination-locked safe designed to offer a moderate degree of protection against attack by common mechanical and electrical hand tools and any combination of these means.
Same as TL-15
Successfully resist entry* for a net working time of 30 minutes when attacked with common hand tools, picking tools, mechanical or portable electric tools, grinding points, carbide drills and pressure applying devices or mechanisms, abrasive cutting wheels and power saws.
* Entry = Safes classed as TL-15 opening the door or making a six square inch opening entirely through the door or front face. Safes classed as TL-30 opening the door or making a six square inch opening entirely through the door or front face.
U.L. Fire Resistive Rating Classification
The following is an explanation of the Underwriter’s Laboratories’ fire resistant container testing procedures on the Class 350°F, one hour and Class 350°F two hour Fire Labels.
U.L. Label/Class 350°F-one hour and Class 350°F-two hour. The safe will maintain an interior temperature less than 350°F when exposed to fire for a period of one hour at 1700°F or for a period of two hours at 1850°F. Safe must successfully undergo all other requirements for the Fire Endurance Test, Explosion Hazard Test and the Fire/Impact Test as stated below.
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 1700°F for a period of one hour, or 1850°F 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 350°F.
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
Explosion Hazard Test
The safe is locked and placed into a furnace preheated to 2000°F. 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.
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 1550°F for a period of 30 min. (2 hour test: 45 min. at 1638°F).
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.