Understanding Lock Grades

Understanding Commercial Lock Grades

Learn the differences between Grade 1 locks, Grade 2 locks, and Grade 3 locks.

Grade 1 Locks – Heavy Duty Commercial

Grade 1 locks are known as the strongest and most secure locks in the industry. Designed specifically for commercial security applications, Grade 1 hardware is ideal for high traffic and potentially high abuse environments, such as schools, hospitals, and commercial buildings. These locks are highly recommended for exterior doors and entry points, as well as areas that require heightened security and frequent usage, including restrooms and cash rooms.

Grade 2 Locks – Standard Duty Commercial

Grade 2 locks are well-suited for commercial applications that experience standard traffic flow, typically less than 100 cycles a day, where the risk of forced entry is lower. Many commercial office buildings opt for Grade 2 hardware in locations like interior offices, exam rooms, and storage closets.

Grade 3 Locks - Light Duty Commercial / Residential

Though not the highest rated, Grade 3 locks still meet the stringent criteria set by ANSI/BHMA. They are generally sufficient for low-security, low-traffic interior applications.

Security hardware undergoes rigorous testing for operability, durability, safety, security, and aesthetics, while also ensuring compliance with applicable building codes, accessibility requirements, and sustainability guidelines. Some standards are consistent across the commercial lock grades, establishing a minimum functionality level, while other tests help identify the best product for specific applications.

(*It’s important to note that all tests are specific to hardware classification; for example, Grade 1 door closers are not subjected to the same tests as Grade 1 lock hardware.)

All mortise lever locks (ANSI/BHMA A156.13), for instance, are required to meet essential Operational, Strength, and Finish criteria:

- Must retract when subjected to 28 inch-pounds or fewer of rotational force

- Must latch when subjected to 4.5 pounds of force or fewer

- Must withstand 360 pounds of pressure applied to the top of the lever

- Must maintain an acceptable appearance after exposure to environmental conditions (salt, humidity, UV rays, etc)

Evaluation of the Cycle, Security, and Material Evaluation tests helps confirm which of the commercial lock grades is best suited for a particular opening:

Functionality Test   |   Grade 1   |   Grade 2   |   Grade 3

-----------------------|-------------|-------------|------------- 

Cycles (Mechanical operations)    |   1,000,000    |   800,000    |   800,000 

Security (Using a ram to impact the cylinder face) | 10 blows at 75 foot-pounds | 5 blows at 75 foot-pounds | 2 blows at 75 foot-pounds 

Material evaluation (Using a pointed probe to impact the lock rose) | 0.075 inch | 0.100 inch | 0.100 inch

Product grade levels for security hardware are determined by the Builders Hardware Manufacturers Association and the American National Standards Institute and are verified by independent laboratories.