Technical Booklet E Fire Safety·Page 167·6.16
Mechanical venting for basements with sprinklers and heat-resistant systems
Basements may use mechanical air extraction systems as an alternative to natural venting, provided they have sprinklers and the extraction system achieves at least 10 air changes per hour and operates at 300°C for 60 minutes.
A basement may be ventilated by a mechanical air extraction system provided –
(a) the basement has a sprinkler system fitted in accordance with Section 8 complying with the relevant recommendations of Section 8 BS 5306-2 or BS EN 12845; and
(b) the air extraction system has a capacity of not less than 10 air changes per hour and is capable of operating at a temperature of 300°C for not less than 60 minutes.
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