· Ventilation systems are required in an enclosed building to satisfy building regulations for health, comfort, and cooling needs.

· Protection against mould due to high air humidity.

· Air is regulated.

· Provides oxygen for metabolism

· Dilutes metabolic pollutants

Indoor Air Quality (IAQ)

Indoor Air Quality (IAQ) deals with the content of interior air that could affect health and comfort of building occupants. The IAQ may be compromised by microbial contaminants (mould, bacteria), chemicals (such as carbon monoxide and radon), allergens, or any mass or energy stressor that can induce health effects


Two common causes of Allergies:

(A) Moisture induced growth of mould colonies.

(B) Natural substances released into the air such as animal dander and plant pollen.

Types of Allergies

· Hypersensitivity

· Pneumonitis,

· Allergic rhinitis

· Asthma.

How can Ventilation systems help?

For allergy sufferers’ ventilation systems with electrostatic filters can bring great benefits. Moisture build-up inside buildings may arise from water penetrating compromised areas of the building envelope or skin, from plumbing leaks, from condensation due to improper ventilation, or from ground moisture penetrating a building part. In areas where cellulosic materials (paper and wood, including drywall) become moist and fail to dry within 48 hours, mould mildew can propagate and release allergenic spores into the air.

In many cases, if materials have failed to dry out several days after the suspected water event, mould growth is suspected within wall cavities even if it is not immediately visible. Through a mould investigation, which may include destructive inspection, one should be able to determine the presence or absence of mould. In a situation where there is visible mould and the indoor air quality may have been compromised, mould remediation may be needed. Inspections should be done by an independent investigator to avoid any conflict of interest and to insure accurate results.

There are some varieties of mould that contain toxic compounds (mycotoxins). However, exposure to hazardous levels of mycotoxin via inhalation is not possible in most cases, as toxins are produced by the fungal body and are not at significant levels in the released spores. The primary hazard of mould growth, as it relates to indoor air quality, comes from the allergenic properties of the spore cell wall. More serious than most allergenic properties are the ability of mould to trigger episodes in persons that already have asthma, a serious respiratory disease.

Ventilation Systems & Air Contaminants

Carbon Monoxide & Ventilation Systems

· Most acutely toxic indoor air contaminant.

· Colourless, odourless gas that is a by-product of incomplete combustion of fossil fuels.

· Common sources are tobacco smoke, space heaters using fossil fuels, defective central heating furnaces and automobile exhaust.

· By depriving the brain of oxygen, high levels of carbon monoxide can lead to nausea, unconsciousness, and death.

· See

Radon & Ventilation Systems

· Radon is an invisible, radioactive atomic gas that results from radioactive decay of some forms of uranium

· Naturally occurring radioactive gas.

· Found in rock formations beneath buildings or in certain building materials themselves.

· Radon is probably the most pervasive serious hazard for indoor air in Europe.

· Radon is a heavy gas and thus will tend to accumulate at the floor level

· Building materials can be a significant source of radon, but very little testing is done for stone, rock or tile products brought into building sites.

· See