IEQ and Health Consequences of Adaptation to and Mitigation of Climate Change
As climate change increases outdoor temperatures, air conditioning will more often be used to maintain comfortable indoor conditions, with both positive and negative effects on health. Increased availability of air conditioning is expected to diminish the increases in adverse health effects resulting from heat waves. When air conditioning is employed, windows are normally maintained closed, consequently, rates of building ventilation with outdoor air are often reduced. By keeping windows closed, indoor air concentrations of some outdoor air pollutants, particularly particles and ozone, from outdoor air are diminished, with associated health benefits. At the same time, indoor concentrations of pollutants from indoor sources will increase, posing health risks. For reasons that are not well understood, air conditioning is associated with increases in acute health symptoms often called sick building syndrome (SBS) symptoms, and also with respiratory health effects associated with asthma. Exposure to microbial contaminants that grow on the often-wet components of air conditioning systems are a possible explanation. Increased use of air conditioning may lead to more of the adverse health effects associated with air conditioning.
To reduce future climate change it will be necessary to reduce building energy consumption; thus, broad application of energy efficiency measures in buildings is expected as climate change advances. Many energy efficiency measures for buildings will influence comfort conditions or indoor air quality positively or negatively. The net effect of building energy efficiency, motivated by climate change, on indoor environmental quality, comfort, and health cannot be predicted with confidence. It is clear that there is a potential to improve comfort and health conditions through strategic implementation of energy efficiency measures.
Approximately 40% of the world’s population employs biomass or coal stoves which are a large source of indoor air particulate matter and other health-damaging indoor pollutants. Biomass and coal-based stoves are also important sources of emissions of black carbon particles and methane to outdoors, which contribute to climate change. Consequently, use of stoves that employ other fuels, emitting less pollution, and the use of more efficient and lower-emitting biomass and coal stoves, are attractive climate change mitigation measures that could improve indoor air quality and health for a very large population.