Technical Booklet E Fire Safety·Page 56·2.51
Storeys divided into different occupancies
Where a storey is divided into multiple occupancies (different ownerships or tenancies), means of escape from one occupancy must not pass through another. If a common corridor is used, it must be either a protected corridor or have a fire detection and alarm system to BS 5839-1 Category L3 standard.
Where a storey is divided into two or more occupancies (i.e. ownerships, tenancies or similar) the means of escape from one occupancy should not pass through any other occupancy.
However, where the means of escape includes a corridor common to two or more occupancies then either it should be a protected corridor, or a fire detection and fire alarm system to BS 5839-1, of at least Category L3 standard, should be installed.
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