fire door

plural fire doors · alternative firedoor

1. A fireproof door designed to stop fires spreading through buildings.

   There are 10,000 fire doors on the Elizabeth Line, including these two at Liverpool Street that have been tested to tolerate a two-hour blaze at temperatures as high as 3,000°C.

   2022 March 23, Paul Bigland, “We're counting down the days”, in RAIL, number 953, page 39, photo caption

2. The door of a furnace offering access to the fire inside.