Basic Fire Door Requirements

- Jan 28, 2019-

1 Introduction

Fire testing of doors and hardware and the resulting labeling authorities granted, is a complex subject that is better understood when basic rules and guidelines are applied.

2 Doors

The fire rating classification of the wall into which the door is installed dictates the required

fire rating of the door. The location of the wall in the building and prevailing building code establish

the wall’s fire rating. The associated door ratings are shown in table 1 below.

2.1 Hourly ratings

Steel fire doors are “rated” by time (in minutes or hours) that a door can withstand exposure

to fire test conditions. Hourly ratings include 1-1/2-hours, 1-hour, 3/4-hour, and 1/3-hour,

with the maximum rating required of any swinging type fire door being three hours.

2.2 Three-hour (180 minute) doors A door with a three-hour fire protection rating

is usually found in walls that separate buildings or that divide a large building into

smaller fire areas. The wall rating is four hours.

2.3 1-1/2-hour (90 minute) doors

Doors rated for 1-1/2 hours are found in 2-hour rated walls. These doors are commonly located

in stairwells, or other enclosures of vertical communication through a building. They

also occur in boiler rooms and in exterior walls that have potential for severe fire exposure

from the outside the building.