Any glazing material used in fire doors is required to be:

• A. Fire rated
• B. Laminated
• C. Tempered
• D. Untreated

Answer: (A)

Glazing in a fire door must be fire-rated. Fire doors are part of the building’s passive fire protection, meant to keep heat, flames, and smoke from moving between compartments for a specified period. The glass set into the door is part of that barrier, so it has to withstand fire exposure for the same duration as the door’s rating. Ordinary glass would fail under heat and could allow a breach of the fire barrier, defeating the door’s purpose. Fire-rated glazing is tested and labeled for use in fire doors, and it must match or exceed the door’s rating. Laminated or tempered glass can be used only if it is specifically rated and listed for fire-door use; otherwise, it does not meet the requirement.