Technical Booklet E Fire Safety·Page 81·2.101
Mechanical ventilation systems under fire conditions
Mechanical ventilation systems must be designed to either direct air movement away from escape routes or shut down automatically in a fire, and recirculating systems must comply with BS 9999 or BS 5588-9 provisions for fire operation.
A mechanical ventilation system should be designed so that in a fire either –
(a) the air movement in the building is directed away from escape routes; or
(b) the system is closed down.
Where the system re-circulates air it should comply with the relevant recommendations of BS 9999 provisions of BS 5588-9 in respect of its operation under fire conditions.
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