Describes a procedure to test the fire resistance of load bearing internal and external walls. External wall fire resistance may be determined under internal/external exposure conditions. Performance is usually evaluated without perforations, e.g. glazing. If it can be shown that the opening is such that load is not transmitted to the perforation, then the perforation does not require testing in the loaded condition. Does not apply to walls containing door assemblies, curtain walls, and non-separating load bearing walls.