Air quality impacted by wood-fire heater smoke in Tasmania

One wood-fire chimney can pollute an entire neighbourhood if it is not used correctly, a senior researcher says.

Menzies Institute for Medical Research head of environmental health research Dr Fay Johnston said wood-fire heater sales are gradually increasing in Tasmania, and it’s having a negative effect on the state’s air quality. 

“The thing about heating wood is you need to keep warm, and it is a good affordable source of heating,” she said. 

But there are a lot of problems associated with heating wood. Dr Johnston said, in terms of local air quality, wood-fire heaters are the most polluting source of home heating known to humanity.

Efficient combustion turns most of the carbon in wood into carbon dioxide and water vapour, but if that doesn’t happen carbon byproducts are made. 

“No matter how good the standard of the modern wood heater it is, it’s still possible to burn byproducts because humans really want to chuck on a log and close the flue,” she said.

Wood fires can emit smoke, soot, smells and a range of toxic compounds which effect air quality and can be a health risk for people with existing heart and lung conditions. 

EPA Tasmania recommends homeowners only burn dry, seasoned firewood; always burn with a flame; don’t let the fire smoulder; and leave the air control open for 20 minutes after reloading.

Dr Johnston said not shutting the flue for 20 minutes after loading wood was the most important tip and it would go a long way to addressing excessive smoke emission. 

While Dr Johnston believes about 80 per cent of wood-fire heaters were used correctly, she said about 20 per cent of people burning incorrectly could cause widespread neighbourhood pollution. 

“Tassie has a problem and it is getting worse,” she said. 

“In a lot of places Tasmanians don’t meet the Australian air quality standards … Longford, Perth and Deloraine all have big problems with their winter air quality.”

Dr Johnston said she would always promote an alternative heating source if it was available. 

Moving away from wood-fire heating required several strategies, but three that might be relevant to Northern Tasmania include subsidies for technology like pellets, cheaper electricity prices and tax breaks for efficient heating, Dr Johnston said.