From New Year's Day, Environment Southland will roll out the next phase of its Regional Air Plan that requires burners installed between January 2001 and September 2005 to be replaced.
Environment Southland compliance manager Donna Ferguson said any open fires and any burners installed between January 1997 and September 2005, come January, were also now effectively non-compliant burners.
The phase-out programme of multifuel and open burners in the Invercargill and Gore airsheds started after the Regional Air Plan was adopted in 2016 to reduce the amount of pollutants being released into those airsheds.
A phase-out approach was decided after looking at how many inefficient burners needed to be replaced, the available tradespeople in Southland, as well as the conversion costs.
The Invercargill City Council website says national environmental standards (NES) approved burners were wood burners that met standards for emissions and thermal efficiency, but currently no multi-fuel or coal burners had NES approval.
Council consenting and environment group manager Jonathan Shaw said council records showed between 1997-2005, 633 multi-fuel burners were installed.
NES required all non-approved burners/boilers within the Invercargill airshed to be phased out by January 1, 2029 and open fires within the city airshed had also been prohibited since 2015.
But homeowners outside the Invercargill airshed area would not need to replace their burners.
Ms Ferguson said Environment Southland no longer provided a funding scheme for upgrading heating options.
There were other organisations like Awarua Synergy which could assist with grants or low-interest loans from a bank, she said.
"We are aware that keeping warm is the main priority for people during Southland winters, but making sure your burner is compliant and the most efficient it can be will help to keep your family warmer and our air healthier."
Solid-fuel burners needed to be properly maintained to get the most efficient use from them and reduce their emissions. Maintenance included cleaning the chimney and replacing burnt out or damaged firebricks.
"Another way to improve your burning for a cleaner, warmer home includes only burning dry firewood in your fireplace, which can be bought from our list of Good Wood Suppliers."
Particulate matter (PM10) could also enter the air from burning wet, painted or treated timber, outdoor burning, industrial sources, dust and pollen.
PM10 acted as a gas that, when breathed in, penetrated deep into the lungs and was associated with multiple health concerns, particularly respiratory diseases and asthma attacks, she said.
Environment Southland air and terrestrial science team leader Nick Talbot said Invercargill exceeded the 24-hour average of 50 micrograms per cum five times in the past year, usually during the winter months, on cold, still nights.
"We know that the PM10 levels rise over winter due to the increase in domestic burning and this can be reflected by the levels of black carbon detected on our air quality monitoring site filters.
"Occasionally, we get peaks of PM10 in summer from large quantities of sea salt blowing from the Pacific Ocean on to the city during windy days.
"We receive exemptions from central government for this type of exceedance because they are caused by natural phenomena," Dr Talbot said.
Burners installed between September 2005 and January 2010 could still be used until January 2030, while those installed between January 2010 and September 2014 could be used until January 2034.
- By Toni McDonald
