Fire-Rated Labels 101

Excerpts from an Expert > Fire-Rated Labels 101

Why Is Fire Rating Important?

Fire-rated doors are designed to serve as a barrier to fire and keep fire from passing through the opening for a specified period of time.  In order for them to operate properly, these doors must have only fire-rated hardware installed.  If non-fire-rated hardware is installed, the entire door opening will lose its fire rating.

fire rated labelFire doors that lose their fire rating will potentially fail to block fire and smoke from passing through the opening.  For example, non-fire-rated locks are not built to withstand the heat (melting point) and/or pressure created by fire.  These locks will likely fail and allow the door to be blown open.  Similarly, electric strikes must be fail secure so that the door remains locked when power fails.  Failures such as these can mean life or death for building occupants, and can cause more extensive fire and smoke damage to your facility.

How To Find Fire-Rated Labels

fire rated label

If you are unsure whether or not a door is fire-rated, look for the UL or WH fire label.  At times, the fire label is easily found, and at others can be quite difficult to locate.  Below are some helpful tips for finding the fire label.

  • Start by looking on the hinge side of the door.  See the pictures below for various UL and Warnock Hersey (WH) labels that you may see.  The critical component to look for is the circled “UL” or “WH.”
  • On wood doors, the fire label can be on the hinge side or top of the door.
  • Over time, the label may get painted over (see image to the side), so check carefully for any raised surfaces.
  • The label may also be located on the top or bottom of the door.
  • Some labels are embossed in the frame, so be sure to feel for any texturing/raised surfaces.

Again, if you are installing hardware on a door that you suspect may have a fire rating, it is very important to check for the fire label to ensure that you install the proper hardware.  If you have any questions about whether or not hardware is acceptable, let us know.  We’re happy to help.  You can also reach out to your local authority having jurisdiction (AHJ) with questions about your local fire and building codes.

fire rated labelfire rated label

4 thoughts on “Fire-Rated Labels 101

  1. What kinds of things will cause a fire rated door lose its rating? If drilling, are there maximum limits for size of holes, number of holes, that sort of thing?

  2. Hi, Jay!

    The only thing that can be done in the field is the installation of hardware with up to 3/4″ holes for mounting hardware as outlined in through in the NFPA 80 2013 Edition. It’s always better to be safe than sorry, so you’ll want to check with your door manufacturer to get specific approval. I hope this helped. If you’d like more information, don’t hesitate to give us a shout!

  3. Katie hope you can help. We have dozens of older wood fire doors from the 60’s and 70’s that have colored dowel on the hinge side signifying the rating. How do I find out what the legend is for the different colors.


Leave a Reply

Your email address will not be published.