Ventilation

After source control, the second key strategy for improving indoor air quality is to increase ventilation. Ventilation increases the amount of outdoor air that comes indoors. It removes stale indoor air and reduces indoor air pollutants. Ventilation also helps limit the build-up of indoor moisture which can contribute to mould growth.

• Open windows and doors;
• Turn on kitchen or bathroom exhaust fans. Bathroom and kitchen fans remove pollutants directly from the room where they are created; and
• Choose new designs. More and more homes now have mechanical systems that bring outdoor air indoors. Some of these systems are energy-efficient and include heat recovery ventilators, so you should look at all of the available options.

Mechanical Ventilation Systems
Heating, Ventilation and Air Conditioning (HVAC) systems perform these important tasks:

• They bring fresh air indoors;
• They vent stale air outside;
• They circulate the air throughout the building; and
• They control temperature and humidity levels.

Note: Not all HVAC systems are designed to accomplish all of the functions above. Many homes and buildings, particularly older ones, do not have mechanical ventilation systems.