One of the most hazardous situations that can be faced in a building is smoke. While fires themselves are often damaging, it is smoke that can cause the most injuries.
In order to protect a building’s occupants, as well as furnishings and equipment that may be damaged by smoke, a smoke control system is needed. A smoke control system controls the flow of smoke in a building in the event of a fire. It keeps smoke from spreading throughout the building and gives the building’s occupants a clear evacuation route, as well as preventing further damage to the building’s interior.
The primary means of controlling smoke movement is by creating air pressure differences between smoke control zones. The basic concept of building pressurization is to establish a higher pressure in adjacent spaces than in the smoke zone. In this way, air moves into the smoke zone from the adjacent areas and smoke is prevented from dispersing throughout the building.
Smoke control systems are either dedicated or non-dedicated. A dedicated smoke control system is installed in a building for the sole purpose of controlling smoke. It is a separate system of air moving and distribution equipment that does not function under normal building operating conditions. Dedicated systems are used for special areas, such as elevator shafts and stair towers that require special smoke control techniques.
Non-dedicated smoke control systems are systems that share components with some other systems such as the building automation (HVAC) system. When activated, the system changes its mode of operation to achieve the smoke control objectives.