Indoor radon trends with building code change in two Canadian cities.

Radon studies were conducted in two Canadian cities, in Halifax, Nova Scotia, and Winnipeg, Manitoba, to evaluate trends in indoor radon before and after the 2010 National Building Code of Canada was adopted into the legally binding provincial building codes in 2011. Participants were recruited in neighbourhoods characterized by newer housing developments. A postcard campaign in each city offered free radon testing to every house in the target areas, and free testing kits were mailed to study participants.

Development of a Bayesian inference model for assessing ventilation condition based on CO meters in primary schools.

Outdoor fresh air ventilation plays a significant role in reducing airborne transmission of diseases in indoor spaces. School classrooms are considerably challenged during the COVID-19 pandemic because of the increasing need for in-person education, untimely and incompleted vaccinations, high occupancy density, and uncertain ventilation conditions. Many schools started to use CO meters to indicate air quality, but how to interpret the data remains unclear.

Regional cost effectiveness analyses for increasing radon protection strategies in housing in Canada.

The incremental cost effectiveness ratios for implementing a recent recommendation to install a more radon resistant foundation barrier were modelled for new and existing housing in 2016, for each province and territory in Canada. Cost-utility analyses were conducted, in which the health benefit of an intervention was quantified in quality-adjusted life years, to help guide policymakers considering increasing investment in radon reduction in housing to reduce the associated lung cancer burden shouldered by the health care system. Lung cancer morbidity was modelled using a lifetable analysis that incorporated lung cancer incidence and survival time for localized, regional, and distant stages of diagnoses for both non-small cell and small cell lung cancer.

RADON INFILTRATION BUILDING ENVELOPE TEST SYSTEM: EVALUATION OF BARRIER MATERIALS.

The performance of radon barrier materials currently available for housing foundations was evaluated using a unique radon infiltration building envelope test system that was designed to test radon prevention and mitigation systems using real world construction techniques. The reduction in radon concentration measured across the air barrier in the foundations has been used to evaluate five representative barrier materials installed in the radon infiltration building envelope test facility. The reduction in radon concentration in the mock house varied from 68% for 6 mil polyethylene to 98% for the spray polyurethane foam.