CPL Lock Installation & Maintenance 3

Question 1

What is the recommended door preparation bore size for a standard US cylindrical lockset?

Accepted Answer

2-1/8 inches

Answer

The standard cross-bore hole for a cylindrical lockset in the US is 2-1/8 inches in diameter to accommodate the lock body.

Question 2

Which ANSI/BHMA grade designation indicates the highest-quality commercial-grade lockset?

Accepted Answer

Grade 1

Answer

ANSI/BHMA Grade 1 is the highest designation, indicating heavy-duty commercial quality with the most rigorous cycle and security testing.

Question 3

A deadbolt throw (bolt projection) should be a minimum of how much to meet typical security standards?

Accepted Answer

1 inch

Answer

A deadbolt should have a minimum 1-inch throw (bolt projection) to adequately engage the door frame and resist kick-in attacks.

Question 4

When a lock cylinder is stiff and difficult to turn with the correct key, what maintenance step should be performed FIRST?

Accepted Answer

Clean and lubricate the cylinder

Answer

Cleaning and lubricating the cylinder is the first maintenance step when a lock is stiff, as dirt and dried lubricant are common causes of binding.

Question 5

In a high-security door frame installation, which reinforcement product is used to prevent door frame kick-in?

Accepted Answer

Strike plate with 3-inch screws and door jamb reinforcement

Answer

A reinforced strike plate secured with 3-inch screws that reach the wall studs, combined with a door jamb reinforcement kit, prevents frame kick-in.

(CPL) Certified Professional Locksmith Practice Test