How can you tell the rating on a fire door by?

You can determine the rating of a fire door by checking for a label or stamp on the door itself, typically located on the edge or hinge side. This label, issued by a testing agency, indicates the fire resistance rating in hours (e.g., 20, 45, 60, 90, or 120 minutes). Additionally, the door's specifications and documentation may provide further details about its fire rating and compliance with relevant building codes. Always ensure the door is properly maintained and installed to retain its fire resistance capabilities.