Smoke is the leading cause of fire fatalities. Smoke control systems — automatic opening vents, mechanical extract, pressurisation of stairwells, and dedicated smoke shafts — protect escape routes and buy time for evacuation and fire-service intervention. BS 9999 sets the overall design framework; BS 7346 covers individual component standards; the Smoke Control Association (SCA) is the UK industry body and publishes the most widely-followed technical guidance for residential buildings.
Residential buildings above a certain height typically use either a natural ventilation design (AOVs on each floor, a vented headroom) or a mechanical shaft (extract per BS EN 12101-6). Designers weigh cost, maintenance burden, and the architectural constraint of the building. Mechanical systems require standby power (dedicated generator or UPS) and commissioning by a specialist engineer — typically an SCA-registered firm.
Commercial and mixed-use buildings use stairwell pressurisation (BS EN 12101-6) for escape route protection in complex or tall buildings, smoke ventilation in covered car parks, and shopping-mall smoke control under CIBSE TM19 or BRE guidance. Performance testing at commissioning includes smoke generation, pressure measurement, and, for residential schemes, demonstration that smoke is vented within the design time.
Listings on INFIRISK filter by SCA membership, geographic coverage, and whether the contractor handles both design and long-term maintenance. Maintenance is non-trivial — annual AOV testing, pressure-stat recalibration, and battery replacement on the fire alarm interface are all common scope.