Workplaces should be adequately ventilated. Fresh, clean air should be drawn from outside the workplace, uncontaminated by discharge from flues or other outlets, and be circulated through the workplace.
Workplaces inside buildings may have natural ventilation, mechanical ventilation (fans or extraction units) or air-conditioning. An air-conditioning system should:
- provide a comfortable environment in relation to air temperature, humidity and air movement
- prevent the excessive accumulation of odours
- reduce the levels of respiratory by-products, especially carbon dioxide, and other indoor contaminants that may arise from work activities
- supply an amount of fresh air to the workplace, exhaust some of the stale air as well as filter and recirculate some of the indoor air.
Natural ventilation should consist of permanent openings, including windows and doors, that:
- in total are the size of at least five per cent of the floor area of the room
- are open to the sky, an open covered area or an appropriately ventilated adjoining room.
Natural ventilation may be assisted by mechanical ventilation.
Enclosed workplaces should be supplied with comfortable rates of air movement (usually between 0.1 m and 0.2 m per second).
