Prevent Respiratory Disorders in Children

Wednesday April 7, 2010

Recent Canadian Scientific Study Brings Hope for Thousands of Parents

Prevent Respiratory Disorders in Children


Heat Recovery Ventilators Prevent Respiratory Disorders in Children.

Montreal, Quebec, April 7, 2010 – Houses today are so well sealed that they can trap humidity and pollutants indoors as a result of insufficient ventilation. Recently, a team of Canadian scientists led by Dr. Tom Kovesi, a pediatric respirologist at the Children’s Hospital of Eastern Ontario in Ottawa, Canada, performed a randomized double-blind, placebo controlled trial1 to determine whether use of heat recovery ventilators (HRV) would increase home ventilation and therefore reduce the risk of lower respiratory tract illness in young children. The team’s verdict? Use of HRVs was associated with an improvement in air quality and reductions in reported respiratory symptoms in children.

The study represents one of the most important conclusions made to this day on indoor air quality in single family dwellings. It was performed in the polar region of Qikiqtaaluk, Nunavut, which has the highest reported rate of hospitalization for a severe respiratory viral infection in infants in the world. Many of these infants need to be flown to Children’s hospitals in Ottawa for treatment and serious long-term pulmonary complications may follow these infections. In collaboration with the local Nunavut Housing Corporation, researchers studied homes in 4 communities. After a search for HRVs capable of performing under extreme cold (-40 C), and appropriate consents were granted, housing units were retrofitted with Constructo™ 1.0 HRV units made by Venmar Ventilation. About half of the HRV units were modified to appear to supply outside air but were only recirculating air. This allowed a comparison between more versus less ventilation. During the study period, scientists recorded ventilation levels, CO2 concentration, temperature, humidity and visits to the community health center for respiratory illnesses in children.


Dr. Kovesi’s study concluded that improving ventilation through the use of HRV devices was associated with an improvement in indoor air quality and significantly reduced the

1randomizeddouble-blind, placebo controlled trial is a scientifically recognized process to conduct research that demonstrates that a treatment is significantly effective. In this case it means first that homes installed with active or placebo HRVs are chosen randomly, and second, with neither the participants nor the researchers knowing who is getting a placebo unit (a disconnected HRV) and who is getting a working HRV unit. A placebo is a treatment that resembles the active treatment, but which isn’t effective. In this study, placebo units looked and sounded like active HRVs, but they circulated air within the houses, rather than increasing ventilation by increasing the supply of fresh air to the house.

incidence of important respiratory symptoms in young Inuit children. “Many elements got our attention,” says Dr Kovesi. “First, the mean indoor CO2 level in homes with active HRVs was 33% lower than in homes with placebo ventilators (disconnected). Indoor CO2 concentration is important as it reflects home ventilation, and our previous research has shown that increased indoor CO2 (or reduced ventilation) is associated with higher risk of lower respiratory tract infections in children. Rates of reported wheezing and rhinitis were significantly lower in the active HRV group”. Dr Kovesi also points out that “the HRVs also significantly reduced relative humidity. Houses in the arctic are dry, and the intervention tended to make the air inside even drier”.

For Pascal Ialenti, President of Venmar, the team’s findings in Ottawa and Nunavut confirm what his own team believed for a long time. “Our own experience taught us that an HRV is an efficient device to reduce CO2 and pollutants in indoor air. Dr. Kovesi's work stresses for the first time, to our knowledge, that a relationship actually exists between use of HRVs in homes and a reduction in the incidence of respiratory disease symptoms in young children. The team’s efforts give a new meaning to anecdotal reports to Venmar from parents whose children suffer from respiratory problems and who installed an HRV to provide them with a healthier home environment”.

Best Choice for Cost/Efficiency Ratio

Don Fugler, Senior Researcher at Canada Mortgage and Housing Corporation, was a member of Dr. Kovesi’s team in Nunavut. In an article published in Building Better - a First Nations National Building Officers Association publication - he makes these recommendations to house builders and inspectors as well: “Well-ventilated houses have healthier residents and less deterioration due to moisture damage. It is worth the effort … For new houses, the least costly system to operate is a fully-ducted heat recovery ventilator (HRV). HRVs should exhaust continuously from bathrooms, kitchen, and basement, and supply air to the bedrooms and living areas”.

Discover How You Can Make a Difference for Your Child

Healthy air is a crucial factor when it comes to the comfort of children with respiratory conditions. Visit to learn how HRVs work and how they can contribute to make your home a cleaner, safer and healthier place for your loved ones. Find how people just like you made the healthy air choice.

About Dr. Tom Kovesi

Tom Kovesi is a pediatric respirologist at the Children’s Hospital of Eastern Ontario in Ottawa, Canada, and associate professor in the Department of Pediatrics, University of Ottawa. He received his MD from the University of Ottawa in 1985, trained in Pediatrics at the Children’s Hospital of Eastern Ontario, the IWK Hospital in Halifax and the Hospital for Sick Children, Toronto, Canada in 1992. He is a senior author of the Canadian Pediatric Asthma Consensus Guidelines and past chair of the Pediatric Assembly of the Canadian Thoracic Society. His research interest in the north commenced when he began providing consultant pediatric respiratory care to children in Qikiqtaaluk (Baffin) Region, Nunavut, in 1998.He has received research funding from the Program of Energy Research and Development, Natural Resources Canada, and Nasivvik Centre (Laval ACADRE), Canadian Institutes of Health Research. His research interests include: respiratory infection in Inuit infants and children, and the relationship between indoor air quality and respiratory health in Inuit children. Other research interests include pediatric asthma and cystic fibrosis.