Ventilation is the mechanical system in a building that brings in "fresh" outdoor air and removes the "contaminated" indoor air.
In a workplace, ventilation is used to control exposure to airborne contaminants. It is commonly used to remove contaminants such as fumes, dusts, and vapours, in order to provide a healthy and safe working environment. Ventilation can be accomplished by natural means (e.g., opening a window) or mechanical means (e.g., fans or blowers).
Industrial systems are designed to move out (exhaust) and bring in (intake) a specific amount of air at a specific speed (velocity), which results in the removal of undesirable contaminants. While all ventilation systems follow the same basic principles, each system is designed specifically to match to the type of work and the rate of contaminant release at that workplace.
Ventilation is considered an "engineering control" to remove or control contaminants released in indoor work environments. It is one of the preferred ways to control employee exposure to air contaminants.
Other ways to control contaminants include:
There are four purposes of ventilation:
An industrial ventilation system has two main parts: a fresh air supply system and an exhaust system.
In general, the supply system is a heating, ventilation, and air-conditioning system (HVAC) and consists of:
The exhaust system consists of:
The Industrial Ventilation series of documents discusses the elements of the exhaust system.