Background from the report
Poor air quality has negative health impacts. In 2022, the Chief Medical Officer published a report on air pollution. The report noted that as measures to reduce outdoor air pollution evolve, indoor air pollution is becoming a bigger proportion of the air quality problem and that action is needed to protect people’s health, including in indoor public spaces over which they have no control.
People spend 80-90% of their time indoors (homes, schools, workplaces, other public spaces and on transport). The effects of poor indoor air quality on health are less well understood than those due to poor outdoor air quality. The indoor environment is more complex and variable than outdoors. Sources and concentrations of pollutants can vary greatly between and within buildings. Several UK research projects are underway to address a range of knowledge gaps.
Indoor pollutant sources include building materials, cooking and heating appliances, consumer products, occupant activities, damp and mould, and the land on which buildings are sited. Concentrations of certain pollutants are higher indoors and can be exacerbated by poor ventilation. Indoor pollutant concentrations are also affected by the infiltration of air from outdoors.
There is strong evidence for associations between certain individual pollutants and overall poor air quality, with an increased risk of respiratory and cardiovascular illness, cognitive impairment and certain cancers.
There are inequalities in risk for some groups in the population. Vulnerable groups include those who are young, elderly or pregnant or those who have respiratory disease; other demographic characteristics associated with an increased health risk from poor air quality include socio-economic status and ethnicity.
Indoor air pollution can be tackled in several ways including removing pollutant sources, improving ventilation, air cleaning, increasing public awareness and legislative changes. There is a trade-off between improving ventilation and reducing the energy consumption of buildings.
The Government has established a cross-department working group and pledged to tackle aspects of indoor air quality in its 2019 Clean Air Strategy. The strategy included several commitments to reduce emissions in the home such as prohibiting the sale of the most polluting fuels and stoves, improving consumer awareness, and giving new powers to local authorities to take action to minimise air pollution.