Fire-Rated Door Closers Explained

Fire doors protect exit routes and keep a fire from spreading through a building. The closer is part of that system, and if it fails to shut the door, the rest of the assembly cannot do its job. This is one job where the small print really matters.

What "3-hour fire rated" means for a closer

A fire rating belongs to the complete opening: door, frame, hinges, latch and closer. A UL listing on a closer says it has been tested for use on such openings. The "3-hour" figure refers to the longest-rated assembly it can be used on. It does not turn an unrated door into a fire door.

Both the DRIWON DN-9500 and DN-8220 are listed by the manufacturer as UL-listed for 3 hours. Always check the label on the door, then match your hardware to it.

Rules that usually apply

NFPA 80 is the standard most commonly used for fire door assemblies in the US. In plain terms:

• The door must self-close and latch without help.
• Do not wedge or prop it open. Standard mechanical hold-open arms are not acceptable on most fire doors.
• If the door must stay open, use an approved hold-open device tied to the fire alarm, so it releases automatically.
• Do not drill extra holes or alter the door beyond what the listing allows.
• Fire door assemblies are subject to regular inspection, commonly once a year.

Local requirements vary, so your fire marshal or building official has the final word.

Common mistakes

• Replacing a listed closer with an unlisted one because it was cheaper.
• Removing the closer because the door was "too hard to open". Adjust the spring instead.
• Using a hold-open arm on a fire door.
• Setting the latch speed so low that the door stops short of latching.

What about delayed closing?

Delayed action, which holds the door for a moment before it closes, is useful on many doors, but the door must still close fully by itself. If you plan to use a long delay on a rated door, confirm the setting with your inspector. Our adjustment guide shows how the valve works. For public buildings, also read the ADA door closer guide, because opening force rules differ on fire doors.

See this UL 3-hour rated closer on Amazon →

How to read a fire door label

Most rated doors and frames carry a small metal or embossed label, usually on the hinge edge of the door and inside the frame. It names the testing lab, such as UL or Intertek, and gives a rating in minutes or hours, such as 20, 45, 60, 90 or 180 minutes. A 180-minute door is the same as a 3-hour door. The label may also state a maximum temperature rise.

No label? Do not assume the door is rated, and do not assume it is not. A painted-over label may still be readable if you look closely. If the door is on a stairwell, corridor, boiler room or between tenants, treat it as possibly rated until someone qualified confirms otherwise.

A simple inspection checklist

NFPA 80 lists what a full inspection covers. Many of the closer-related points are easy to check yourself between formal inspections:

• The door closes fully and latches from any open position.
• The closer is not leaking and all its screws are in place.
• Nothing holds the door open: no wedge, no strap, no hook.
• The arm is connected, and the closer has not been disconnected.
• The door does not bind in the frame or drag on the floor.
• Gaps around the door have not grown because of worn hinges.
• No unapproved holes, plates or modifications have been added.

Who should install a closer on a rated door?

A competent person can usually swap a listed closer using existing prepared holes. New holes are a different matter, because rules cover what may be done in the field and what must be done by the manufacturer. If in doubt, use a qualified door hardware installer and keep a record of the work for your next inspection.

Picking the right closer for a rated door

Look for a closer that clearly says it is listed for fire doors, then match it to the door width, weight and mounting. The DN-8220 is described for approved fire-rated wood or metal doors, and the DN-9500 carries a 3-hour UL listing too. Choose by door, not by duration alone: a 3-hour listing does no harm on a 90-minute door.

Frequently asked questions

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