National air quality standards

2016

The NEPC established national ambient air quality standards in 1998 as part of the National Environment Protection Measure for Ambient Air Quality (Air NEPM). The Air NEPM sets standards for the 7 key air pollutants to which most Australians are exposed: carbon monoxide, lead, nitrogen dioxide, ozone, particulate matter (PM10 and PM2.5) and sulfur dioxide (Table ATM4).

Following much review and consultation, the Air NEPM, which had been last updated in 2003, was amended on 4 February 2016 with the following changes:

  • The PM2.5 standards were upgraded to performance standards from their previous status as advisory reporting standards.
  • A standard for 1-year average PM10 of 25 μg/m3 was added. This complements the existing standard for 24-hour average PM10 of 50 μg/m3.
  • The allowance for exceedance of the PM standards on a maximum of 5 days per year was replaced by an ‘exceptional event rule’. An exceptional event is a fire or dust occurrence that adversely affects air quality at a particular location; causes an exceedance of 1-day average standards in excess of normal historical fluctuations and background levels, and is directly related to bushfire, jurisdiction-authorised hazard reduction burning or continental-scale windblown dust.
  • A goal was added of reducing the 1-year and 24-hour PM2.5 standards from 8 to 7 μg/m3and 25 to 20 μg/m3, respectively, by 2025.
  • A PM2.5 population exposure metric was added, to be reported on annually from June 2018. Development of this metric is still in progress, but a nationally consistent approach will be used for evaluation and reporting based on agreement by participating jurisdictions.
Table ATM4 National Environment Protection Measure for Ambient Air Quality (Air NEPM), updated 2016

Pollutant

Averaging period

Maximum concentration

Maximum allowable exceedances (goal)

Carbon monoxide

8 hours

9.0 ppm

1 day per year

Lead

1 year

0.50 µg/m3

No exceedance

Nitrogen dioxide

1 hour

1 year

0.12 ppm

0.03 ppm

1 day per year

No exceedances

PM10

1 day

1 year

50 µg/m3

25 µg/m3

No exceedances (see note)

PM2.5

1 day

1 year

25 µg/m3

8 µg/m3

20 µg/m3 (2025 goal)

7 µg/m3 (2025 goal)

No exceedances (see note)

Photochemical oxidants (as ozone)

1 hour

4 hours

0.10 ppm

0.08 ppm

1 day per year

1 day per year

Sulfur dioxide

1 hour

1 day

1 year

0.20 ppm

0.08 ppm

0.02 ppm

1 day per year

1 day per year

No exceedances

PM2.5 and PM10 = particulate matter less than 2.5 microns and 10 microns, respectively; ppm = parts per million; μg/m3 = micrograms per cubic metre

Note: Before 2016, there was an allowance of 5 exceedances per year for the PM standards. This was replaced in 2016 by an exceptional event rule. An exceptional event is a fire or dust occurrence that adversely affects air quality at a particular location, causes an exceedance of 1-day average standards in excess of normal historical fluctuations and background levels; and is directly related to bushfire, jurisdiction-authorised hazard reduction burning or continental-scale windblown dust. The handling of exceptional events in the reporting of averages is specified in the Air NEPM.

The jurisdictions (6 states and 2 territories) monitor air quality at about 75 locations across Australia. These stations are in the major metropolitan areas and some regional centres, and are sited to measure air quality that is representative of that likely to be experienced by the general population in the region. Jurisdictions report annually on their compliance with the Air NEPM based on the data from their monitoring networks.4 Some jurisdictions have additional monitoring networks, such as the NSW Upper Hunter Air Quality Monitoring Network (OEH 2016), but results from these stations are not included in the above compliance reports.

Keywood MD, Emmerson KM, Hibberd MF (2016). Ambient air quality: National air quality standards. In: Australia state of the environment 2016, Australian Government Department of the Environment and Energy, Canberra, https://soe.environment.gov.au/theme/ambient-air-quality/topic/2016/national-air-quality-standards, DOI 10.4226/94/58b65c70bc372