Monitoring Armidale's Air Quality

Air quality in Armidale is monitored by the Armidale Dumaresq Council at the Civic Administration Building in Rusden Street.

Of most concern are fine particles less than 2.5 microns in diameter, known as PM2.5s. These particles bypass the body's defences and penetrate deep into the lungs where they can cause damage. (What's all the fuss about?)
Both in Armidale and in Sydney, nephelometers are used to measure this pollution. They measure the coefficient of light scattering, which, after heating the air to remove water droplets, is very closely related to the concentration of PM2.5s.
One scattering coefficient unit is approximately equal to 20 micro-grams per cubic metre of PM2.5.

Comparison of Armidale with Sydney - 1996 & 1997

A NSW EPA report found that "The Metropolitan Air Quality Study confirmed air quality in Sydney is prone to the accumulation of fine particles, manifesting as a brown haze. ... solid fuel home heaters contribute about 2-3 times the amount of particles in winter in the Sydney region, compared with motor vehicles. This is supported by the high ratio of particles from wood burning in Sydney's winter air, as determined by carbon dating."

Carbon dating of samples taken in July and August 1993 at Rozelle, near the Sydney CBD found that 67% of particulate air pollution originated from burning wood. For Winmalee, in the Blue mountains, 81% of this was from wood burning. Note that only about 13% of Sydney households use wood for home heating.

In Sydney, air pollution is described as low (L) (nephelometer coefficient less than 1.05),
medium (M) (less than 2.1) or high (2.1 or more). The neph coefficient used is the highest hourly value.
Comparison of Armidale with Sydney has fuller explanation of Sydney index.

In Armidale, the scales were rounded and two extra categories added, as shown in Table 1.

Table 1: Armidale Air Pollution Index
Category Low Medium High Very High EXtreme
Neph Coefficient 
(max 1-hour average)
< 1 1 - 2 2 - 4 4 - 8 > = 8
Equivalent PM2.5 (micrograms/cubic metre) < 20 20 - 40 40 - 80 80 - 160 >= 160

Latest Air Pollution Data

Air Pollution in East Armidale 1997
Comparison of Armidale with Sydney - 1996 & 1997  Updated 28 October 1997

Relief map of Armidale with air pollution levels by area