Massachusetts Unrestricted Construction Supervisor License Practice Test

What is the maximum allowed area of wired glass panels in a 1.5 rated fire door located in an exterior wall?

1. 100 square inches

2. 1,296 square inches

3. 120 square inches

4. 0 square inches

The correct answer is: 0 square inches

Wired glass panels are not allowed in fire doors that have a 1.5-hour fire rating when located in an exterior wall. This restriction is established primarily for safety and to maintain the integrity of fire-rated assemblies. Fire doors are designed to prevent the spread of fire and smoke, and the inclusion of wired glass, even though it is generally more heat-resistant than regular glass, compromises the fire-resistance rating of the door. Allowing any area of wired glass could lead to a failure in the door's performance during a fire event, potentially allowing flames and smoke to pass through. Therefore, the building codes specify that for 1.5-hour rated fire doors in exterior walls, the maximum allowed area of wired glass panels is zero square inches. This is a critical point for construction supervisors to ensure compliance with safety regulations and maintain the proper functionality of fire safety systems in buildings.