More on Corridor Doors

Q: If the corridor doors are only required to resist fire for 20 minutes and someone plasters signage all over them or loads them up with coat racks adding to the fuel load, then who decides if they would still resist fire conditions for 20 minutes?

A: The doors are not required to resist fire for 20 minutes. They are required to be 1¾ inch thick, solid-bonded, wood core, or of such construction that resist fire for not less than 20 minutes. That is not the same as saying they are required to resist fire for 20 minutes.  Therefore, nobody has to decide if they still resist fire for 20 minutes, because the construction of the door was determined acceptable before any items were added to the door. This may sound like a technical loop-hole, but the point I’m trying to make is there should not be a reason for anyone to determine if a corridor door resists fire for 20 minutes. NFPA has indicated that a 1¾ inch solid-bonded, wood-core door is of such construction to resist fire for up to 20 minutes (see section of the 2000 LSC).