| Pollutant | Estimated monetary benefit of achieving the proposed air quality standard |
|---|---|
| CO | $34 million - reduced health treatment costs |
| NO2 | $4.5 million - reduced health treatment costs |
| O3 | $95 - 285 million - reduced health treatment costs |
| SO2 | $12.5 million - reduced health treatment costs |
| PM10 / PM2.5* | $850 million - reduced health treatment costs $4 billion - avoided deaths |
* PM10 is particulate matter composed of particles less than
10 micron in diameter; while PM2.5 is composed of fine particles
less than 2.5 microns in diameter.
The current proposed air quality standard is 50 micrograms/cubic
metre maximum 24-hour average for PM10, and 25
micrograms/cubic metre for PM2.5. Latest research indicates that
PM2.5 relate more closely to the health data. Only the PM2.5
standard is relevant for smoky areas, since woodsmoke is almost
entirely PM2.5.
The above table, from p52 of the National Environment Protection Council discussion document (downloadable from http://www.nepc.gov.au - look for NEPM on Ambient Air Quality) gives estimated benefits of various air pollution control measures.
The report acknowledges the major role played by wood heaters in urban air pollution and suggests that careful consideration should be given to "a restriction on the use of wood heaters in major airsheds say, in 10 years time. This might be the most cost effective means of achieving the two thirds goal which would allow recent purchasers of new wood heaters time to amortise the capital costs and time to prepare for a new source of domestic heating in the next century".
The benefits of measures to control particulate pollution, estimated to save $4 billion in avoided deaths and $850 million in reduced health treatment costs, indicate particulate pollution is far and away the most serious and costly pollutant.
The health cost savings are based on the number
of days when the standard is exceeded multiplied by the
number of people exposed to the pollution - the number of
person-day exceedences.
The following table table compares the person-day exceedences
of PM10 for Sydney, Perth, and Launceston
(where woodsmoke pollution is high):-
| City | Person-day Exceedences |
| Sydney | 11.8 million |
| Perth | 1.7 million |
| Launceston | 12.1 million |
Launceston, with a population of approximately 100,000 therefore has more person-day exceedences than Sydney with a population of 3 million!!! In terms of exceedences per person, the problem is 30 times worse in Launceston, than in Sydney. Yet in Sydney, a study by NSW Health estimated that 400 people die every year from particulate air pollution. It was found that particle levels (and deaths) are higher in Sydney in the colder months, when carbon dating of air samples found two thirds of fine particles originate from the 13% of households which burn wood.
Surprisingly, even in Perth, carbon dating and other techniques found wood burning (mainly woodstoves in winter, and burn-off at other times of the year) accounted for 3 times as much particulate air pollution as motor vehicles. (Gras, J. L. (1996). The Perth Haze Study: a report to Department of Environmental Protection of Western Australia on fine-particle haze in Perth. Aspendale, Vic.: CSIRO Division of Atmospheric Research. 145, 16 p. )
Daily average data for
Armidale compared with proposed standard.