How to Tell If a Door Is Fire Rated?

A fire-rated door is a door that has been designed to withstand a certain degree of extreme heat per hour. Fire doors are the most common fire-rated doors. When people talk about the fire rating of a door, they are most often referring to the strength of a fire door. Different safety agencies, such as the Office of Compliance Safety and Health, measure how efficiently a door can maintain its integrity during a fire emergency. A high fire rating means that the door can withstand fires for long periods of time. If you are concerned about the fire rating of a door, there are several steps you can take to assuage your fears.

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Fire doors must have a fire rating, which indicates how strong the door can guard against the intensity of a fire.

Step 1

Make sure the door is a fire door and not an emergency door. Emergency doors are wired to alarm systems. Fire doors can be used for casual purposes but have a special use during fires.

Step 2

See if a louver is present on the door. Louvers are slats through which smoke can pass. They are usually on medium-level doors; lower level fire-rated doors usually do not have louvers.

Step 3

Open the door completely so that all latches are exposed. Many markings and indicators may be exposed when you have the door open.

Step 4

Investigate the areas between each door latch. A label should show what temperature the door can withstand; this is known as the temperature holding. Temperatures vary, but a door must at least have a temperature holding of 250 degrees Fahrenheit.

Step 5

Measure the glass thickness. Not all fire doors will have a glass window. If the fire door does have a glass window, the glass must measure at least ¼ inch in thickness. If it does not, then the door does not meet the Housing and Urban Development's legal definition of a fire door.