Technical Booklet E Fire Safety·Page 119·Diagram 4.7
Fire-resisting ceiling requirements
Ceilings below cavities must have at least 30 minutes fire resistance, be imperforate except for specified openings, extend throughout the building or compartment, and not be easily demountable.
The ceiling should –
(a) have at least 30 minutes fire resistance;
(b) be imperforate except for an opening described in paragraph 4.42;
(c) extend throughout the building or compartment; and
(d) not be easily demountable.
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