Definitions for Fire Safety

In this Technical Booklet the following definitions apply – Above ground level – has the meaning assigned to it by regulation 32 in Part E of the Building Regulations. Access room – a room that forms the only escape route from an inner room. Accommodation stairway – a stairway, additional to that or those required for escape purposes, provided for the convenience of occupants. Alternative escape routes – escape routes sufficiently separated by either direction and space, or by fire-resisting construction, to ensure that one is still available should the other be affected by fire. Alternative exit – one of two or more exits, each of which is separate from the other. Appliance ventilation duct – a duct provided to convey combustion air to a gas appliance. Atrium (plural atria) – a space within a building not necessarily vertically aligned, passing through one or more structural compartment floors. (The term does not include enclosed lift wells, enclosed escalator wells, building services ducts and stairways.) Automatic fire detection and alarm system – a system incorporating smoke detectors, sounders, control equipment, protected wiring and a back-up power supply which is capable of automatically detecting smoke and thereupon giving an audible alarm. Automatic release mechanism – a device which will allow a door held open by it to close automatically in the event of each or any one of the following – (a) detection of smoke by automatic apparatus suitable in nature, quality and location; (b) operation of a hand operated switch fitted in a suitable position; (c) failure of electricity supply to the device, apparatus or switch; and (d) operation of the fire alarm system where fitted. Automatic self-closing device – a device which is capable of closing a door from any angle and against any latch fitted to the door. [The term does not include rising butt hinges unless the door is – (a) to (or within) a dwelling; (b) between a dwellinghouse and its garage; or (c) in a cavity barrier.] Basement storey – a storey with a floor which at some point is more than 1.2 m below the highest level of ground adjacent to the outside walls.