By removing smoke, a correctly designed smoke control and heat exhaust ventilation system, helps create a smoke free layer above the floor and by doing so, improves the conditions for the safe escape and/or rescue of people of the buildings occupants, together with protection of property.  It also permits the fire to be fought by the firefighters, while still in its early stages.

 

The use of smoke control and heat exhaust ventilation systems to create smoke free areas beneath a buoyant smoke layer has become widespread. Their value in assisting the evacuation of people from buildings, reducing fire damage and financial loss by preventing smoke logging, facilitating firefighting, reducing roof temperatures and retarding the lateral spread of fire is firmly established. For these benefits to be obtained it is essential that smoke control and heat exhaust ventilators operate fully and reliably whenever called upon to do so during their installed life. A smoke control and heat exhaust ventilation system is a scheme of safety equipment intended to perform a positive role in a fire emergency.

 

When applied as a properly designed smoke control and heat exhaust system, ventilation systems help to;

 

  • allow sufficient time for occupants to escape and keep access routes free from smoke

  • facilitate firefighting operations by creating a smoke free layer

  • delay and/or prevent flashover and thus full development of the fire

  • protect building, equipment and furnishings

  • reduce thermal effects on structural components during a fire

  • reduce damage caused by thermal decomposition products and hot gases

 

Depending on the design of the system, powered or natural smoke and heat ventilators can be used in a smoke and heat control system, in conjunction with smoke curtains which generally form the fire compartmentation or plume channelling function.

 

Assisted by the buoyancy of the hot smoke, natural ventilators are regarded as the first choice design, recognising the extraction rate is self-compensating.  In areas of wind shadow or where natural ventilation is impractical, powered smoke and heat exhaust ventilators can be installed in either the upper areas of the building or via a ducted system.  In all cases whether natural or powered ventilation is used, failsafe operation should be ensured.

 

The design of smoke and heat exhaust ventilation systems depend on;

 

  • design fire size

  • distance from fire source to ventilator

  • temperature of the smoke

  • size, number and location of the exhaust openings

  • design of sprinkler application

  • wind effects

  • size, geometry and location of the replacement air openings

  • system actuation time

  • the location and conditions of the system (e.g. arrangements and dimensions of the building).

  • Smoke and heat exhaust ventilation systems are used in buildings where the particular dimension, shape or configuration make smoke control necessary.

 

Typical examples being:

 

  • Shopping malls

  • Industrial buildings and warehouses

  • Atria and complex structures

  • Theatres and exhibition halls

  • Enclosed car parks

  • Stairways

Why do I need

Smoke Control?