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Cracking the Code: A Glimpse into UL’s Burglary Testing of Safes

UL engineers are working hard to “crack the code” on safes, providing peace of mind for business owners.

UL conducts burglary test on a safe, ul conducts a safe cracking test

September 10, 2019

TV and movie crime thrillers portray thieves and spies breaking into safes by turning the dials and listening closely for clicks to crack the combinations. The real safe-crackers can be found inside the labs at UL, attempting to break-in with acetylene torches and air-powered hammers.

UL’s testing of safes addresses the most common risks to securing valuables: fire and burglary. This post addresses the second of those risks.

UL tested its first safe for burglary resistance in 1923 and its first bank vault in 1925. Today its technicians test a wide variety of commercial and residential safes, including automated teller machines (ATMs) and security containers, using a number of break-in methods — from common hand tools, torches and chemicals to explosives.

Before starting a test, UL technicians analyze the blueprints to a commercial safe to identify the weak points and plan out where and how to attack it. Their goal is to create an opening that’s large enough to remove its contents or pry open the door within a specified period of time.

UL’s most basic test addresses a combination-locked safe designed to offer limited protection against common mechanical and electrical tools. UL technicians attack the safe for 15 minutes using hand tools, picking tools, mechanical or electrical tools, grinding points, carbide drills and devices that apply pressure.

At the more extreme end, UL technicians test a combination-locked safe designed to offer protection not only against these types of tools but also against cutting devices, such as power saws and high-level explosives like nitroglycerin. Additionally, UL technicians either attack the door and front face, or the door and body. Because of the size and shape of some safes and vaults, UL technicians travel all over the world to conduct their tests on-site.

UL collaborates with experts in security and the banking industries to help develop its standards and test methods. Upon completion of safe testing, manufacturers receive ratings that indicate a safe’s resistance to attack against specific tools and for a specified period of time.

While no safe is “burglar-proof,” safes that meet the UL standard offer a level of protection that makes it more difficult for thieves to access its contents. UL engineers are working hard to “crack the code” on safes, providing peace of mind for business owners.

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