Current Woodheater 'Standards' don't reduce real-life emissions

The only tests of real-life emissions of wood heaters satisfying current standards are from New Zealand. They show that real-life emissions averaged 8 times worse than the lab test and were little different from emissions of older wood heaters used in Australia - see 'Health Cost of Allowing New Wood Heaters – over $3,000 per heater per year' for more details of the tests on all 35 households.

The table (left) shows some results from a study in Christchurch, New Zealand in 2009, where average real-life emissions were 12 times worse than the lab test measurements.  This was one of 4 studies from 2003 to 2009 involving a total of 35 households;  real-life emissions averaged 6.5 g/kg wood, much higher than the average ANZS4013 ratings of 0.85 g/kg for the same models [2].  Tighter standards have been tried in Christchurch since 2002 when the limit for all new wood stoves was reduced to 1.0 g/kg.  From April 2010, Christchurch prohibited the use of wood heaters more than 15 years old [3]. Despite the fact that the vast majority of wood stoves in Christchurch have emissions ratings of less than 1.0 g/kg and only 18% of households in metropolitan Christchurch use log-burning heaters [4], Christchurch exceeded the WHO PM2.5 guideline of 25 ug/m3 on 22 days in 2013. The majority of exceedances were from May to August (the colder months) and attributed to home heating emissions [5].  Given the failure of the much stricter limit of 1.0 g/kg in Christchurch, the less stringent limit for new heaters in Australia has no hope of achieving significant reductions in woodsmoke pollution.

The lower the lab test result, the greater the discrepancy with real-life emissions. Real-life emissions of stoves rated below 0.65 g/kg averaged 9 times worse; those rated 0.65 to 0.95 averaged 7.6 times worse; those rated 0.95 to 1.2 g/kg averaged 6.2 times worse. This is another indication that the lab test doesn’t reflect real-life. See 'Health Cost of Allowing New Wood Heaters – over $3,000 per heater per year' for more details of the tests on all 35 households. 

Tasmanian Research

Recent research on woodsmoke-reduction in Tasmania was summarised by Dr Fay Johnston’s talk to the International Woodsmoke Researchers Network see slide left.  This research shows that improved heater emissions standards, education on improved use of heaters and retro-fitting catalyst technology are all ineffective - the best and most cost-effective solution is to transition to non-polluting heating.

New woodheaters emit more PM2.5 per year than 1,000 petrol cars.  The estimated health costs of woodsmoke pollution is more than $8 billion just in NSW - more than $22,000 for every wood heater in the state.
     The health costs are extremely high because research has shown there is no safe level of PM2.5 pollution, considered to be the most dangerous air pollutant, responsible for 10-20 times as many premature deaths as the next worst pollutant, ozone.
     PM2.5 pollution from cars and sports utility vehicles was slashed by the development of new standards. Although adding about $980 to the price of the average diesel SUV, the latest Euro5/6 standards are considered well worth the $1.5 billion saving over the next 20 years in health costs for Australia A SUV travelling 20,000 km per year must emit less than 0.1 kg PM2.5.
      Recommendations by the Australian Standards Committee (approved 15 votes to 4) to reduce wood heater emissions couldn't be implemented because they were vetoed by representatives of the Australian wood heating industry. After this veto, research to develop a new wood heater standard and real-life emissions test was abandoned.
      As shown in the Briefing Woodsmoke_Discussion_paper_Nov2012 the current test for log-burning heaters does not reflect real-life emissions. Even a very low rating of 1 g/kg translates into average real-life emissions of 6.4 g/kg with emissions of 13.3 kg PM2.5 and estimated health costs of $3167 per year in Sydney.  
      Australia's real-life emissions tests were carried out in Launceston, after a $2 million woodsmoke education program. Knowing their emissions were being measured, the volunteers were keen to operate heaters correctly - many refuelled them in the middle of the night, to ensure they did not smoulder overnight. Even after spending millions on eduction, keen, motivated volunteers in Launceston could not achieve anything like the lab test emissions. The only realistic way to reduce emissions is therefore to develop a real-life emissions test and set a standard based on limiting health impacts to an acceptable level.
      Other industries have co-operated by substantially reducing emissions, so the average brand-new wood heater in Sydney now emits as much PM2.5 pollution as 190 new diesel SUVs, and has estimated health costs of more than $4,000 per year - see the Briefing Woodsmoke_Discussion_paper_Nov2012 The latest NSW EPA emissions inventory show that, despite being used by only a small proportion of households in Sydney, wood heaters emit a whopping 51% of annual PM2.5 emissions in Sydney (compared to 14.4% for all on-road cars, trucks and other vehicles in Sydney)
      Not allowing new log-burning heaters to be installed (until a new health-based standard has been developed) would cost $134 million, but save $2,206 million in health costs. Requiring existing wood heaters to be removed when houses are sold would cost just $36 million, but generate health benefits of $4,015 million - see Briefing Woodsmoke_Discussion_paper_Nov2012 Alternatives such as wood pellet heaters (with much lower real-life emissions) would be allowed.
      The UN Environment Program (UNEP) recommends phasing out wood heaters in developed countries to reduce methane and black carbon emissions (which cause a substantial proportion of global warming as well as ill health)
      The State Government has already adopted policies that do not allow log-burning heaters in Sydney's prestigious Oran Park and Turner Rd Growth precincts. Other Councils (such as Waverley and Holroyd) that have checked out the horrific statistics on the amount of pollution from current wood heater models, also do not permit new log-burning heaters to be installed.
       Wood heaters produce many dangerous pollutants in addition to PM2.5, including PAH, which is linked to genetic damage in babies and also behavioural problems and reduced IQ when children start school. In developing countries, children whose mothers cook with wood (as opposed to kerosene) stoves, have reduced cognitive function and social skills
      People and organisations who care about their health, or the health and IQ of their children, should therefore make their views known by taking part in the consultation process. Allowing new heaters that emit even 20 times as much pollution as the health-based standard for a SUV should not be considered acceptable, let alone 190 times as much (in Sydney) or 400 times as much (in colder areas that burn an average of 4 tonnes of firewood per year). E
mail or fill out the online form by 30 November 2012. pointing out that the pollution from current Australian wood heater models is not acceptable. Therefore, until a new health-based standard has been developed, we should not allow new log-burning to be installed, and require existing ones to be removed when houses are sold.
Further information
1. NSW EPA Discussion paper: Options for wood smoke control in New South Wales - Discussion paper. State of NSW and Environment Protection Authority  2012.
Economic appraisal of wood smoke control measures. Available at:
2.            Wilton, E., Review - particulate emissions from wood burners in New Zealand, 2012, National Institute of Water and Atmospheric Research.  Available at

3.            Robinson, D.L., What makes a Successful Woodsmoke-Reduction Program? Air Quality and Climate Change, 2016. 50(3-4).

4.            Smithson, J., Inventory of emissions to air in Christchurch, 2009. Report No. R11/17 ISBN 978-1-927146-24-8, 2011, Environment Canterbury.  Available at:

5.            MFE & Statistics NZ. PM2.5 concentrations. 2015  21/9/2016].

6.            Gilmore, H. State's top doctor says we should consider banning wood fire heaters. Sydney Morning Herald, July 5. 2014 July 5; Available from:
     Armidale's policy led to the installation of heaters rated less than 2.5 g/kg, such as the one in the photo.  This level of emissions was observed for a considerable period of time from a brand new heater in a new house.
     The Australian wood heating indstry argues that this level of emissions is a perfectly acceptable standard to that could be introduce by the end of 2013.  Any anything better would affect their profitiability.
     With estimates that heaters rated 2.5 g/kg have real-life emissions of at least 7 g/kg (see Table from the Briefing _paper ), and estimated average health costs of more than $3,500 in Sydney and $1,700 in colder regional areas, is clear that AHHA, set up to represent the wood heating industry, considers its profits more important that people's health.
Table 1.  Comparison of lab-test and real-life emissions for new heaters, estimated health costs for a heater installed in Sydney and in colder rural areas, and the number of Diesel SUV required to produce the same amount of annual emissions - details see the Briefing _paper



Colder rural area





Health Cost

1 wood heater = Diesel SUV


Health Cost

=Diesel SUV

4 g/kg

9.8 g/kg

18.6 kg



39.2 kg



3 g/kg

7.6 g/kg

16.8 kg



35.3 kg



2 g/kg

7.0 g/kg

14.4 kg



30.2 kg



1 g/kg

6.4 g/kg

13.3 kg



28.0 kg



AECOM Office of Environment & Heritage: Economic Appraisal of Wood Smoke Control Measures - Final Report, 29 29 June 2011.  Emissions by lab test rating, table 15 (9.8 g/kg for limit of 4 g/kg); table 18 (reductions of 10%, 22.9%, 28.6% and 34.3% for ratings of 3, 2 and 1 g/kg respectively).  Table 24 - estimated Health costs for capital cities ($235.26/kg PM2.5) and rural areas $55.82/kg PM2.5).  Estimates are based on assumes average firewood consumption of 1.9 tonnes per year in Sydney and 4 tonnes per year (the average for Armidale, NSW and Canberra) in a cold rural areas.
The NSW Economic Analysis and Dicussion paper provide estimates of the costs and benefits of variatious woodsmoke control option, shown in the table below.  People and organisations who care about their health, should strongly support all options with large health benefits for minimal cost.
Table 2. Estimated health benefits and costs of woodsmoke control options in NSW


Health Benefit

Cost $million

Net Benefit $million

4) Phase out at sale of house




2) Ban on heater sales




7) Licensing fees




6) Sales tax on new wood heaters




9) Cash incentive phase out




8) Levying an excise/tax on biomass fuels




5) Fuel moisture content regulations




3) Emission standards (3g/kg, 60% efficiency)




Source:  Tables 26 and 28, AECOM Office of Environment & Heritage: Economic Appraisal of Wood Smoke Control Measures - Final Report, 29 June 2011