6. Smoke extraction (Article U 26)

§ 1 The establishments referred to in Articles U are class 1 for the purposes of determining the coefficient as defined in the appendix to Technical Instruction no. 246 [TBA 3 049] .

In addition, on levels with sleeping quarters, common horizontal corridors and corridors (internal and enclosed from floor to floor) in compartments of any length must be mechanically smoke-extinguished.

In exceptional cases, buildings with no more than one storey above the first floor may be naturally smoke-free, after consultation with the relevant Safety Commission....