Enclosure which is fire-resistive for a predetermined period of time

An enclosure which is fire resistive for a predetermined period of time comprising:

• a floor affixed upon a forging;
• walls extending vertically from said floor;
• a ceiling connected to said walls, and
• a door and a window formed in said walls, said floor and said walls and said ceiling and said door and said window being made of fire-resistant materials, said floor constituted by a glass wool felt layer of incombustible material, a platform being affixed onto said glass wool felt layer, said platform being composed of several wooden plates glued one to another, said wooden plates having an expansion joint attached thereon, a wooden skirt board attached to an upper side of said wooden plates and said expansion joint, said expansion joint being sandwiched between said walls and said wooden plates, said door comprising a frame having a plurality of wooden parts having a steel plate extending across at least one face thereof.