To limit the probability that light-frame construction walls, columns, arches, beams and loadbearing steel elements exposed to fire will fail or collapse prematurely, which could lead to the failure or collapse of the floor or roof assembly above during the time required to achieve occupant safety and for emergency responders to perform their duties, which could lead to harm to persons.
To limit the probability that light-frame construction walls, columns, arches, beams and loadbearing steel elements exposed to fire will fail or collapse prematurely, which could lead to the failure or collapse of the floor or roof assembly above, which could lead to the spread of fire from a lower storey of a building to an upper storey or to the exterior during the time required to achieve occupant safety and for emergency responders to perform their duties, which could lead to harm to persons.