Low wind conditions are causing high air pollution days in Hastings.
"There's not much we can do about the weather, but the amount of smoke we produce is something we can change and need to change to achieve health standards regardless of the weather," Hawke's Bay Regional Council's air quality scientist, Dr Kathleen Kozyniak said.
The National Air Quality Standard - set at 50 micrograms of PM10 per cubic metre - has been exceeded seven times in Hastings this year. This is twice what the regional council had hoped for. None has been recorded in Napier.
The air pollution problem is caused by smoky air being trapped close to the ground when inversion layers form in the atmosphere over the plains during cold, low wind conditions. The small particles in smoke cause a health issue inside and outside homes, especially for people with respiratory problems.
Hawke's Bay Regional Council's Heat Smart manager Mark Heaney said since 2009 - when the council began providing grants and loans to help people upgrade to modern wood burners - 8700 wood burners have been replaced.
Many other homes are likely to have upgraded as well, without the use of HBRC funding.
"Pre-2005 wood burners generate noticeably more smoke than modern appliances. People should go outside on a cold, still night and check how much smoke is coming from their flues and surrounding their home and neighbourhood," he said.
Heaney said people don't have to put up with lots of smoke around their home. Residents can contact HBRC on the Pollution Hotline if they are experiencing a lot of smoke or smelly smoke.
"You can have a fire that produces low levels of smoke with some good management. Lots of smoke means there's a problem with the wood burner, the material being burnt or the fire-lighting technique," he said.
"Ask yourself the question: is your money going up in smoke? Any smoke you see is unburnt fuel. While you can expect to see some smoke on start up (until the fire reaches a good temperature), after 20 mins from lighting, the more smoke, the more money you're wasting and the worse the impact on our health."