Nitrogen dioxide (NO2) is a gas. Breathing it in can irritate your throat and lungs.

Nitrogen dioxide is a common air pollutant. In Victoria, nitrogen dioxide levels are usually low. We measure nitrogen dioxide at some of our air monitoring sites.

Sources of nitrogen dioxide

The main sources of nitrogen dioxide in Victoria include:

Health effects of nitrogen dioxide

Breathing in high levels of nitrogen dioxide can affect your health. You’re more likely to have symptoms if you:

Symptoms can include wheezing, coughing and shortness of breath.


Infographic showing the health impacts of Nitrogen dioxide.

Nitrogen dioxide on EPA AirWatch

We show nitrogen dioxide data on EPA AirWatch using air quality categories.

Air quality category Nitrogen dioxide averaged over 1 hour (parts per billion)
Good   Less than 60
Fair   60–120
Poor   120–180
Very poor   180–360 
Extremely poor   More than 360

Current standards for nitrogen dioxide

We compare our nitrogen dioxide data to national air quality standards. These are incorporated into the Environment Reference Standard.
National standard in parts per million (and parts per billion) Averaging time
0.08 ppm (80 ppb) 1 hours
0.015 ppm (15 ppb) Annual

Read more about air quality

Air pollution

Carbon monoxide in the air

Ozone in the air

PM10 particles in the air

PM2.5 particles in the air



Sulfur dioxide in the air

Air pollution and visibility

Vehicle emissions and air quality

Wood smoke and air quality

Clean air and future air quality

Your health and the environment: learn and take action

Reviewed 30 March 2022