North Carolina Locksmith Practice Exam

What UL rating represents a mechanical combination lock that can withstand reasonable expert manipulation?

1. Group 1

2. Group 1R

3. Group 2

4. Group 2M

The correct answer is: Group 1R

The UL rating system classifies locks based on their ability to resist manipulation. A Group 1R mechanical combination lock indicates that it has been tested and found capable of withstanding "reasonable expert manipulation." This rating suggests that while the lock can resist certain skilled attempts to bypass it, it is not impervious to all forms of skilled manipulation. Group 1 locks, on the other hand, are more basic and do not necessarily meet the same standards of resistance. Group 2 locks are considered more secure than Group 1 and are typically designed to resist more sophisticated attacks, but the Group 2M specifically indicates that it can withstand moderate manipulation attempts without being compromised. Thus, the Group 1R designation is specifically tailored to indicate that it can endure manipulation attempts from someone with some level of expertise, differentiating it from other groups that either do not emphasize manipulation as much or offer greater resistance.