Specification C1.10 and C1.10a are a means of satisfying the performance requirements of the BCA. In other words it is up to the relevant building surveyor to decide whether any proposed deviations from the fire hazard indices (fire indices for materials) set out in the specification would still be acceptable. If the building surveyor will not accept the variation, the matter may be referred to the relevant state Building Appeals Board for determination.
Fire indices for materials/ fire hazard properties are not readily available for all materials and it is therefore necessary that material manufacturers have their products tested in accordance with Specification A2.4. A lot of manufacturers list their fire indices for materials on their websites.
Generally there are two sets of requirements in Specification C1.10. One relates to the limitation on the use of materials (fire indices for materials) in fire-isolated stairways, passageways and ramps and the other relates to the remainder of the building. The former requirements are obviously the most stringent as it should not be possible for a fire to occur or to spread in a fire-isolated exit.
The following is a part extract of clause I1.1 for an Essential Safety Measure (as appeared in BCA 2013) known as fire indices for materials and assemblies required to have fire hazard properties:
Table I1.6 SAFETY MEASURES – BUILDING FIRE INTEGRITY