Air quality categories

Our Check air and water quality map gives you current air quality information and forecasts air quality for the next 24 hours.

We use 5 categories to describe the overall air quality at each of our monitoring sites across Victoria:

• Good
• Fair
• Poor
• Very Poor
• Extremely Poor

Poor, Very Poor or Extremely Poor means the level of a pollutant is higher than its air quality guideline or standard. 'No data' means there is no data available.

We give general health advice for each category. This includes steps you can take to protect yourself from the short-term effects of air pollution.

We also give advice for people sensitive to air pollution. These are:

• people with a heart or lung condition, including asthma
• people over the age of 65
• infants and young children
• pregnant people
• people with diabetes.

Learn more about how we monitor air quality.

Visit Air pollution to learn more about managing your health and air pollution.

Air quality categories

Good

Air pollution is at usual background levels.

Advice for the general community

No change needed to your normal outdoor activities.

Advice for people sensitive to air pollution

No change needed to your normal outdoor activities.

Fair

Air pollution is above usual background levels.

Advice for the general community

Keep track of conditions. No change needed to your normal outdoor activities.

Advice for people sensitive to air pollution

• Keep track of conditions, and be prepared to take action if air quality gets to Poor, Very Poor or Extremely Poor.
• Monitor any health conditions.

Poor

The air is likely to be dusty or smoky.

Advice for the general community

• Keep track of conditions.
• Consider taking steps to reduce your exposure to polluted air if poor conditions last longer than one day.
• See advice for the general community under Very Poor, below, for a list of actions to consider.

Advice for people sensitive to air pollution

Consider taking steps to reduce your exposure to polluted air using one or more of these strategies:

• Reduce outdoor physical activity, especially if you develop symptoms like coughing or shortness of breath.
• Keep track of conditions, and consider closing windows and doors until outdoor air quality is better.
• Use a portable air cleaner with a HEPA filter if you have access to one.
• Use a P2 or N95 mask, but seek advice from your doctor if you have a pre-existing heart or lung condition.
• Go to a place with cleaner air – such as an air-conditioned building like a library or shopping centre – if it's safe to do so.
• Follow the treatment plan recommended by your doctor. If you're concerned about symptoms, call Nurse-on-Call on 1300 60 60 24 or see your doctor.
• If you or anyone in your care has trouble breathing or tightness in the chest, call triple zero (000) for an ambulance.

Very Poor

The air is very dusty or smoky.

Advice for the general community

Consider taking one or more of the following steps to reduce your exposure to polluted air:

• Reduce outdoor physical activity, especially if you develop symptoms like coughing or shortness of breath.
• Keep track of conditions, and consider closing windows and doors until outdoor air quality is better.
• Use a portable air cleaner with a HEPA filter if you have access to one.
• Use a P2 or N95 mask, but seek advice from your doctor if you have a pre-existing heart or lung condition.
• Go to a place with cleaner air – such as an air-conditioned building like a library or shopping centre – if it's safe to do so.

Advice for people sensitive to air pollution

Take action to reduce your exposure to polluted air, especially if you have a medical condition that is not under good control. Use one or more of these strategies:

• Avoid outdoor physical activity if you develop symptoms like cough or shortness of breath.
• When indoors, close windows and doors until outdoor air quality is better.
• Use a portable air cleaner with a HEPA filter if you have access to one.
• Use a P2 or N95 mask when outdoors, but seek advice from your doctor if you have a pre-existing heart or lung condition.
• Go to a place with cleaner air – such as an air-conditioned building like a library or shopping centre – if it's safe to do so.
• Follow the treatment plan recommended by your doctor. If you're concerned about symptoms, call Nurse-on-Call on 1300 60 60 24 or see your doctor.
• If you or anyone in your care has trouble breathing or tightness in the chest, call triple zero (000) for an ambulance.

Extremely poor

The air is very dusty or smoky.

Advice for the general community

Take action to reduce your exposure to polluted air using one or more of these strategies:

• Stay indoors as much as possible with windows and doors closed until outdoor air quality is better.
• Use a portable air cleaner with a HEPA filter if you have access to one.
• Use a P2 or N95 mask.
• Go to a place with cleaner air – such as an air-conditioned building like a library or shopping centre – if it's safe to do so.
• If you're concerned about symptoms, call Nurse-on-Call on 1300 60 60 24 or see your doctor.
• If you or anyone in your care has trouble breathing or tightness in the chest, call triple zero (000) for an ambulance.

Advice for people sensitive to air pollution

Take action to reduce your exposure to polluted air using one or more of the these strategies:

• Stay indoors with windows and doors closed until outdoor air quality is better, and reduce indoor activity.
• Use a portable air cleaner with a HEPA filter if you have access to one.
• Use a P2 or N95 mask when outdoors, but seek advice from your doctor if you have a pre-existing heart or lung condition.
• Go to a place with cleaner air – such as an air-conditioned building like a library or shopping centre – if it's safe to do so.
• Actively monitor symptoms and follow the treatment plan recommended by your doctor.
• If you're concerned about symptoms, call Nurse-on-Call on 1300 60 60 24 or see your doctor.
• If you or anyone in your care has trouble breathing or tightness in the chest, call triple zero (000) for an ambulance.
  

How we calculate air quality categories

To calculate the air quality category, we measure the average concentration of a pollutant in the air over one hour. We then compare this measurement to the pollutant's air quality guideline or standard.

We measure these pollutants:

• ozone
• nitrogen dioxide
• sulfur dioxide
• PM_2.5 particles
• PM₁₀ particles
  
• carbon monoxide.
  

Concentration ranges for air quality categories

Calculating overall air quality

We compare the concentration of each pollutant. We use the highest concentration as the overall site category. The results for each site show which pollutant we used to determine the category.

Air quality data from our sensor network is based on indicative measurements of PM_2.5 particles in the air.

Air quality standards and accreditation

The National Environment Protection (Ambient Air Quality) Measure (Air NEPM) sets national standards for the key air pollutants to which most Australians are exposed.

Environment Ministers review national air quality standards every 2 years. To learn more, visit National Clean Air Agreement on the Department of Climate Change, Energy, the Environment and Water website.

The Air NEPM standards are part of the Environment Reference Standard.

We assess the data we get from our monitoring against the Environment Reference Standard. We also use this data to calculate our air quality categories.

We meet all Australian Standards for air quality measurement and are accredited with NATA. Our NATA accreditation number is 15119.

Our work with HiVols (PM₁₀) and Partisols (PM_2.5) is currently done by a contractor. They use our sites and air monitoring equipment.

We locate our monitoring sites in places that give a good representation of the air quality experienced by the community. Australian Standard 3580.1.1:2016 specifies that air monitoring sites should be more than 50 metres from a road. Currently, none of our monitoring sites meet these requirements in full, because they are located in high population centres with existing infrastructure and roads.

Air pollution model

The air pollution model currently approved for regulatory purposes in Victoria is the AERMOD air pollution model. AERMOD is the preferred and recommended model of the United States Environmental Protection Agency.

To use AERMOD, you must follow the requirements in the Guidance for assessing and minimising air pollution.