Christmas and New Year is a time when many people will be at home. Being indoors can give us a degree of protection from outdoor air pollution, but it can also trap pollution we produce inside our homes.
Risks from secondhand tobacco smoke are well known and the effect is perhaps best seen by comparison of health data before and after indoor smoking bans. A study of 47 indoor smoking bans in public spaces found hospital admissions for heart attacks decreased by an average of 12%, but people are less aware of other indoor pollutants and how to minimise them.
Dr James Heydon and a team from the University of Nottingham measured air pollution in 20 UK homes for four weeks. Each had a Defra “approved” wood stove, exempted for use in smoke control areas.
“We found that wood burning can trigger sharp spikes in indoor air pollution,” he said. “The biggest increases were associated with routine stove management like lighting the stove, opening the door to refuel, and tending the fire.”
Teams from Imperial College London and the University of Surrey found similar results in their studies of homes in south-east England and in Cornwall.
Heydon said: “To try to reduce their indoor pollution, refuel less often, open the stove door as slowly and briefly as possible, and avoid frequent top-ups. Other research has also highlighted the role of ventilation. Users could also consider not lighting their fires when children, or people with health conditions, are in the same room.”
Wood and coal-burning can also affect neighbours.
Using freedom of information requests, the campaign group Mums for Lungs found about 15,000 complaints are being made annually to local councils about smoke from neighbours’ fires.
Heydon said: “Recognising that wood-burning stoves are not harmless appliances is the first step in reducing exposure. Simple choices, like not lighting a stove on poor air quality or low wind days, improving ventilation, and avoiding frequent refuelling can help make a real difference.”
Cooking also adds to indoor air pollution. Prof Sarah West from the University of York is part of the Ingenious study that measured air pollution in 310 homes in Bradford. “In our Bradford homes the highest particle pollution was related to cooking,” she said. “Frying was a particularly big source.”
West’s message is simple: “We were talking about solutions in a research meeting. I came up with ‘pan on, fan on’ and it stuck. We had magnets made up to stick to cooker hoods, so that people would see it, and when they put their pan on to cook, they would also turn their fan on.”
The research team also recommend turning on the extractor or opening windows when using cleaning products and scented sprays around the house.
