Specifies compressed asbestos fibre jointing for general purposes in sheets. Covers Grade A for use with water, inert gases, inert liquids or steam up to 64 bar and 510°C, and Grade B for use with water, inert gases, inert fluids or steam up to 16 bar and 230°C. Specification includes composition, quality and finish, density, and thicknesses and tests for compression, flexibility after accelerated ageing and stress relaxation.