CRL Lock Installation & Repair 5

Question 1

What is the standard thickness of a residential exterior door?

Accepted Answer

1-3/4 inches

Answer

Exterior residential doors are typically 1-3/4 inches thick; interior ones are often 1-3/8.

Question 2

How many hinges are typically used on a standard 80-inch door?

Accepted Answer

3

Answer

Three hinges is the standard for a 7-foot door; heavy doors may need four.

Question 3

Why might a code officer object to a double-cylinder deadbolt in a residence?

Accepted Answer

It requires a key to exit, impeding fire egress

Answer

Keyed-both-sides locks can trap occupants during emergencies, so many codes restrict them.

Question 4

Which tool is used to cut the 2-1/8 inch cross bore in a door?

Accepted Answer

Hole saw

Answer

A 2-1/8" hole saw cuts the face bore for cylindrical locks, usually using a jig.

Question 5

A master key system commonly uses what in the pin stack?

Accepted Answer

Master wafers or master pins creating a second shear line

Answer

Additional pins create two shear lines so two keys open the same lock.

CRL - Certified Registered Locksmith Practice Test