By The Home Ventilating Institute (HVI)
When you think about it, ventilation really is a people consideration. The purpose of ventilation is to provide a home’s occupants with clean, healthy, and comfortable air.
Ventilation is used to dilute pollutants and supply occupants with oxygen. Ventilation also dilutes high indoor humidity levels to prevent moisture-related problems such as mold growth and rot. Controlling excess moisture protects both the health of occupants and the health of the house.
While air infiltrating a house will dilute the concentration of indoor contaminants, natural infiltration is unreliable when compared to mechanical ventilation. In fact, it has been determined that houses with mechanical ventilation systems have better indoor air quality and use less energy than houses that rely on natural infiltration alone.
The words “sick-building syndrome” imply that a building is ill, when in fact the phrase refers to conditions which make the occupants ill—generally as a result of poor indoor air quality. Complaints may be reported after a building is remodeled. Pollutants released from construction products or cleaning solutions, microbial contamination of wet materials, and inadequate ventilation, are often cited as causes of sick-building syndrome.
Incidences of sick-building syndrome are on the rise. Fortunately, however, as more and more people grasp that poor indoor air quality might be the cause of their illnesses, they are cleaning up their indoor environment and improving their ventilation.
Some people, due to pre-existing conditions (e.g., health, age) are more sensitive to contaminants in the air. Sensitive people require air that is much cleaner than normal in order to minimize negative impacts on their health. Their condition is often referred to as chemical sensitivity or multiple chemical sensitivity (MCS). Many of us are sensitive to “bad air” to a less debilitating degree – and all of us can derive a substantial benefit from breathing cleaner air.
Individuals with MCS generally exhibit a wide variety of symptoms. Eye and respiratory irritation are common, but headaches are also widely reported. Other symptoms can range from joint and muscle pain to seizures. Because the brain is very sensitive to some pollutants, MCS patients often report symptoms such as depression and anxiety that are related to poor indoor air quality.
Sensitive people’s bodies react to very low levels of a wide variety of pollutants. So, for sensitive occupants, it is imperative to clean up the indoor air through source control and separation, then use a mechanical ventilation system to keep the air clean.
Diluting high moisture levels
Although moisture itself isn’t a pollutant, with an accumulation over several days, it can contribute to a variety of pollution problems in a house. If there is excess moisture in a house in the form of high humidity, there can easily be a proliferation of biological pollutants. Mold, mildew, or dust mites will start to thrive as the humidity rises, and the occupants may start experiencing allergy or asthma symptoms. Inside the living space, moisture can be released from both people and their activities. Spot ventilation in the kitchen and bath, along with a whole-house ventilation system will help to expel excess moisture from a house.
People need fresh air
Those who are at greatest risk for sensitivity to contaminated indoor air are children, the elderly, and the sick. But we all need fresh air. We spend between 80–90% of our time indoors, so we must ensure that the air is comfortable and healthy. Properly installed ventilation products that have been certified by the Home Ventilating Institute (HVI) will ensure that you receive proper ventilation to maximize indoor air quality.
John P. Lapotaire, CIEC
- Certified Indoor Environmental Consultant
- Indoor Air Quality Solutions, IAQS
- Microshield Environmental Services, LLC
- www.Microshield-ES.com www.CFL-IAQ.com