BS 476-21 Fire tests on building materials and structures — Part 21: Methods for determination of the fire resistance of loadbearing elements of construction

1 Scope
This Part of BS 476 describes procedures for determining the fire resistance of loadbearing elements of building construction when subjected to the heating and pressure conditions specified in BS 476-20. This Part provides requirements for specimen selection and/or its design and construction, loading and restraint conditions, equipment, procedures and criteria as they apply to loadbearing specimens. The methods are applicable to beams, columns, floors, flat roofs and walls.

The methods described are not applicable to suspended ceilings protecting steel beams which are described in BS 476-23 (see A.1). Owing to limitations imposed by both the furnaces and their method of control, structures employing water cooling techniques are not capable of being evaluated realistically by these procedures.

The methods described are not applicable to assemblies of elements, e.g. wall/floor combinations, although some guidance is provided in Appendix A for tests of this type (see A.1).

NOTE The titles of the publications referred to in this standard are listed on the inside back cover.

2 Definitions
For the purposes of this Part of BS 476, the definitions given in BS 476-20 and BS 4422 apply. elements of construction