Technical Booklet E Fire Safety·Page 160·6.3
Firefighting Shafts - When Required
Buildings must be provided with one or more firefighting shafts in various circumstances: storeys more than 18 m above fire and rescue access level; certain Purpose Groups with storeys 900 m² or more at 7.5 m or higher; storeys more than 10 m below access level; multiple basement storeys of 900 m² or more; or shopping complexes per BS 9999.
A building should be provided with a firefighting shaft or shafts, to serve all storeys, where –
(a) it has a storey more than 18 m above fire and rescue access level;
(b) it is a building of Purpose Group 4, 5, 6 or 7(a) and has a storey 900 m² or more in area at a height of 7.5 m or more above fire and rescue access level;
(c) it has a storey more than 10 m below fire and rescue access level; or
(d) it has two or more basement storeys any of which is 900 m² or more in area; or
(e) it is a shopping complex, in accordance with the relevant recommendations of BS 9999.
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