When a fire door closes, it must latch to prevent it from being forced open by the pressure from a fire. NFPA 80 requires fire doors to have an active latchbolt that can not be held retracted, except in the case of electrified hardware incorporating a mechanism that automatically latches the door if a fire occurs.
The latching requirements of NFPA 80 are fairly complex, because they address single doors, active and inactive leaves of pairs (including coordinators), and electrified hardware such as electric latch retraction, electric strikes, and stairwell reentry. The standard also includes requirement for fasteners used to install latching hardware, allowable job-site preparations and field modifications, and methods for filling fastener holes left by the removal of hardware.
These requirements are summarized in this blog post, with links to additional resources. After reading the summaries and reviewing the referenced information for any requirements that you’re unfamiliar with, proceed to the review questions below.
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Review Questions
1. In which location would a deadbolt typically be allowed on a fire door assembly?
- A stairwell door that serves a maintenance penthouse
- The entrance door to an individual apartment
- A door to an electrical room containing high-voltage equipment
- A cross-corridor double-egress pair
2. Which of the following combinations may be used on pairs of fire doors?
- Constant-latching flush bolts, coordinator, lever-handle lockset
- Vertical rod fire exit hardware on both leaves
- Labeled two-point latching hardware on both leaves
- All of the above
3. Which of the following is NOT true of the auxiliary fire pin used with less-bottom-rod/cable fire exit hardware?
- It latches each time the door closes
- It projects when a high temperature is reached
- It is allowed by the model codes
- It keeps the leaves of a pair aligned during a fire
Answers: 1 – B, 2 – D, 3 – A