The National Environment Protection Council made the National Environment Protection (Air Toxics) Measure in 2004. The monitoring investigation levels are the concentrations of an air toxic which, if exceeded, requires an appropriate form of further investigation and evaluation.

Pollutant Averaging period Monitoring investigation levels
Benzene Annual
3 ppb
Benzo(a)pyrene Annual 0.3 ng/m3

24 hours

40 ppb
24 hours
1000 ppb
100 ppb
24 hours
250 ppb
200 ppb

Annual: the annual average concentrations are the arithmetic mean concentrations of 24-hour monitoring results.

24 hours: monitoring over a 24-hour period is conducted from midnight to midnight.

ppb: parts per billion (for every billion litres of air there is one litre of the pollutant).

ng/m3: nanograms per cubic metre (1 billionth of a gram per cubic metre).

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How EPA monitors air quality in Victoria

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EPA AirWatch



This page was copied from EPA's old website. It was last updated on 23 October 2013.

Reviewed 25 November 2021