7. Smoke extraction in public areas (DF 7)

Smoke extraction is natural or mechanical when the surface area reaches :

• more than 100 m ² in the basement ;

• 300 m ² first floor and upper floor;

• over 100 m ² with no opening to the outside (door or window).

A volume connecting no more than three storeys must be cleared of smoke in a single room, as soon as the cumulative surface area of floors accessible to the public reaches 300 m ² .