Master Lock Meets New ASTM Lock Bumping Standard

March 3, 2010

Taking steps to combat a security problem that has increasingly touched the lives of homeowners, tenants, property managers, security directors as well as businesses nationwide, ASTM International ( has developed testing criteria under its Standard F883-09 for determining a cylinder’s ability to effectively resist break-ins using lock bumping techniques. The revised Standard can be used to test and compare pin tumbler cylinders commonly used in padlocks and door hardware.

“In order to quickly assess the impact this Standard could have, tests on 13 brands of lock cylinders using new ASTM criteria have been conducted by professional locksmiths at the request of Master Lock Company,” said senior marketing manager David Kearns.

In these series of tests, locks from only two manufacturers attained the highest level of protection - Grade 6 - as specified in the Standard.

Both padlocks and door hardware from Master Lock Company exceeded Grade 6 lock bump test criteria, thanks to patent-pending, BumpStop® Advanced Cylinder Technology, Web Site:

“The development of these testing criteria by ASTM International recognizes the importance of lock bumping as a broad-scale security issue, and emphasizes the need for industry standards with which to measure performance of specific lock products,” said Master Lock Company’s Billy B. Edwards Jr., CML.

During the past few years, Edwards pointed out, extensive media publicity and internet “bump key” sales have turned what once was a little-known (and legitimately used) locksmith technique into a mass-market problem. Bump keys are readily available and the bumping procedure is so easy “an 11-year-old can do it.”

According to safety experts, 90 percent of American homes are at risk of having a lock bumped, enabling unauthorized entry. Untold numbers of businesses multiply potential bump-caused security and property loss problems.

“With this revised ASTM Standard in place, security professionals and end users alike can cut through the confusing barrage of claims for ‘high security’ locks,” Edwards emphasized. “They can simply ask for a lock that provides Grade 6 lock bumping protection.”

“It only takes one,” summed up Kearns. “Just one bump can pop a lock, putting people and property at risk. Professional locksmiths couldn’t bump our locks after hundreds of attempts.”

Professional locksmiths attack the locks in this test using the new ASTM Standard criteria, which requires that five locks be tested by each of three locksmiths using both a “Pull” and a “Push” bump key. Both types of keys have uniform steeples between cuts and, when struck, are forced further into the lock. A “Push” bump key, however, centers itself after each impact, whereas a “Pull” bump key must be pulled back from the lock one space position after being struck, before another attempt.

Bump key test requirements are as follows:

Grade 1: Must withstand 60 impacts

Grade 2: Must withstand 120 impacts

Grade 3: Must withstand 180 impacts

Grade 4: Must withstand 240 impacts

Grade 5: Must withstand 300 impacts

Grade 6: Must withstand 360 impacts

Standard F883-09, section 9.6, establishes six Grade Levels, each of which calls for 20 bump attempts by each locksmith, 10 with each type of key for a total of 60 bump attempts in order to attain one level of security. If all 60 attempts fail to bump the lock, it is deemed to have passed that grade level. If only one lock fails or opens from just one bump attempt, all locks are deemed to have failed at that level.