CRL Cheat Sheet 2026

The 30 highest-yield CRL facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which device prevents door movement when power is lost in a fail-safe system? → Mechanical latch
2. Which machine is most commonly used for duplicating standard house keys? → Manual duplicator
3. In ALOA master key system notation, what does the abbreviation 'MK' designate? → The master key that operates all change key locks within its designated group
4. Which tool is used to measure the depth of existing cuts on a key? → Depth gauge or key caliper
5. In master key system design, what does 'total positions' (TP) refer to? → The number of possible bitting depth variations available per pin position
6. What is the key difference between a code-cutting machine and a tracing duplicator? → Code machines cut from bitting specifications rather than tracing an original
7. Why should graphite never be used in a lock that already contains oil? → The mixture forms a sludge that binds the pins
8. When a new customer calls to verify a locksmith's credentials, what is the most professional response? → Provide license number, ALOA membership, and offer to show credentials upon arrival
9. If a copy cut from a worn original does not operate smoothly, the best remedy is to: → Recut from the lock's code or a less worn key
10. Under the IBC, panic hardware is required on egress doors in Group A and E occupancies with an occupant load of at least: → 50
11. Which door closer adjustment controls door speed during the last few inches before the door latches? → Latch speed valve
12. Which factor most directly affects the pricing of a locksmith service call after normal business hours? → Emergency or overtime labor rates reflecting increased cost and inconvenience
13. What is the main purpose of a key blank cross-reference guide from Ilco or Silca? → Matching a key to the correct compatible blank
14. Why must many transponder keys be programmed after cutting? → The vehicle must learn the chip's code
15. What is the recommended minimum deadbolt throw length for a residential door to meet basic security standards? → 1 inch (25 mm)
16. Which door closer mounting places the arm parallel to the door face on the push side? → Parallel arm mount
17. Which organization publishes building codes that often include door hardware and lock standards? → ICC
18. Why are double-cylinder deadbolts generally problematic on egress doors in commercial occupancies? → They require a key to exit
19. What is a 'restricted keyway' used for in key control systems? → Preventing unauthorized duplication by making the keyway proprietary
20. What is the purpose of a cylinder retaining clip? → Secure the cylinder in place
21. Which device on a panic bar door allows electric dogging or remote unlocking of the outside trim? → Electric latch retraction or electrified trim
22. Fire door assemblies are tested to UL 10C, which evaluates doors under: → Positive pressure fire exposure
23. On a surface vertical rod exit device, the top latch doesn't engage the top strike. What is the usual adjustment? → Adjust the top rod length or latch position
24. What advantage do 13.56 MHz smart cards have over 125 kHz proximity cards? → They support encryption and mutual authentication
25. When learning new installation techniques & methods in Certified Registered Locksmith, which approach is MOST effective? → Combining theoretical study with supervised practical application
26. What is the role of data in quality control & inspection programs for Certified Registered Locksmith? → Data provides objective evidence for decision-making and measuring progress
27. In Certified Registered Locksmith, how should quality control & inspection initiatives be prioritized? → Based on impact on outcomes, feasibility, and alignment with strategic goals
28. Which tool is best for removing a broken key from a lock cylinder? → Key extractor
29. When removing a plug from a pin tumbler cylinder to rekey it, which tool keeps the top pins and springs in the shell? → Plug follower
30. In Certified Registered Locksmith, how should project estimation & planning challenges be prioritized? → Based on potential impact, urgency, and alignment with strategic objectives