Technical Booklet E Fire Safety·Page 17
Sealing and subdivision of hidden voids
Hidden voids in construction must be sealed and subdivided to inhibit the unseen spread of fire and products of combustion, reducing the risk of structural failure and fire spread that threatens occupant safety.
if any hidden voids in the construction are sealed and subdivided to inhibit the unseen spread of fire and products of combustion, in order to reduce the risk of structural failure, and the spread of fire, in so far as they pose a threat to the safety of people in and around the building.
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