Fire doors must be checked regularly as they are essential for protecting escape routes and maintaining compartmentation. They are usually made of wood or steel and are designed to provide 30 to 60 minutes of protection. But before you think about installing one, it's important to understand how they work and how to find the right door for you. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay Identifying Fire Doors Wooden fire doors normally require a gap of around 3-4 millimeters between the door leaf and the frame. To maintain fire resistance, the cavity is normally protected by an intumescent seal installed in the door or frame. Intumescent gasket expands to seal gaps when a fire tragedy occurs. If the door contains a glass panel, it will normally also have intumescent material. To limit the spread of smoke at room temperature, anti-smoke gaskets can also be fitted. Occasionally metal fire doors may be more appropriate than wooden ones, for example when fire resistance of more than one hour is required. To identify a port and its rating you should look for a label or cap from a third-party certification scheme. Labels Labels or caps from certified suppliers are a reliable indicator that a door meets the designated fire rating. Labels usually indicate the length of time a door will resist fire. Each label is usually numbered. This is helpful in tracking down the door manufacturer if a replacement is needed or problems occur. The old doors have labels. But if they are of solid, heavy construction and similar to other fire doors in buildings, they are probably fire doors. If you are unsure, you should get a professional opinion on the door's performance or install a proven replacement. Clearances Clearances around fire doors should be three to four millimeters. Larger spaces are unlikely to hold fire and smoke. In older buildings, doors may not have intumescent strips, so you can expect a fire rating of only 20 minutes. The current recommendation is that a door with a flash strip be installed that offers a minimum of 30 minutes of fire resistance. Metal doors usually do not come with intumescent strips. Smoke seals Many fire doors are now fitted with smoke seals which prevent the spread of smoke at normal temperatures. These seals are usually polymer blades or brushes. An assessor should verify that smoke seals are present and in good condition. They should completely fill the space between the doors and the frame. Hardware The hardware of fire doors is complex. The combinations of hinges, closures and push plates are almost infinite and many are not compatible with each other or with particular types of door and frame. Most fire doors will be hung on three or more hinges. If the door has fallen due to a failure of the hinges or fixings or if the door does not close properly, repair work should be undertaken as soon as possible. Fire risk assessors should also check the presence and condition of intumescent seals. They should be mounted on the top and both side edges of the door. Intumescent hardware protection should also be used to prevent premature door failure. This is especially important for doors.