Vehicle emissions

There are two types of emissions that impact on the environment, air quality and human health: greenhouse gas emissions and air pollutant emissions.

Greenhouse gas emissions, such as carbon dioxide (CO₂), trap heat from the sun in the earth’s atmosphere, causing the ‘greenhouse effect’ and climate change. CO₂ is the main greenhouse gas produced by motor vehicles.

Air pollutant emissions emitted by motor vehicle exhausts include:

• carbon monoxide (CO),
• nitrogen oxides (NOx),
• particulate matter (PM); and
• volatile organic compounds (VOC).

These emissions can cause smog, heart and lung disease and cancer.

Greenhouse Gas Emissions

Motor vehicle exhausts also produce greenhouse gases that contribute to climate change. The main greenhouse gas produced by vehicles is carbon dioxide (CO₂), but they also produce nitrous oxide and methane. In 2024-2025, emissions from the transport sector accounted for around 23 per cent of Australia’s total emissions, with passenger and light commercial vehicles comprising around 60 per cent of transport emissions.

The Department of Climate Change, Energy, the Environment and Water maintains Australia's National Greenhouse Accounts which has more information on the emissions of greenhouse gases in Australia.

On the Green Vehicle Guide (GVG), a higher CO₂ number means a car emits more carbon dioxide (CO₂) from its tailpipe. All new vehicle models up to 3.5 tonnes gross vehicle mass sold in Australia must have their fuel consumption and the CO₂ emissions tested before they are sold in Australia. Some new vehicles up to 4.5 tonnes gross vehicle mass sold in Australia may also report their tested fuel consumption and CO₂ emissions on the Green Vehicle Guide.

In 2019, the average new light vehicle sold in Australia produced 181 grams of CO₂ per kilometre (g/km).The National Transport Commission estimates that if Australian consumers bought the most efficient vehicle in its class, CO₂ emissions for new light vehicles would be 63 percent lower.

Air Pollutant Emissions

Air pollutants can cause smog and adversely affect human health. Further information on these impacts is available from the Department of Climate Change, Energy, the Environment and Water.

Motor vehicles remain a major source of air pollutants, especially where there is more traffic. However, many vehicles have cleaner exhausts that produce less air pollutants than others.

Vehicles that meet a higher air pollution standard (‘Euro level’) produce less air pollutants than equivalent vehicles meeting a lower standard. The air pollution standard section of the results page advises the air pollution/‘Euro’ standard a vehicle model meets in Australia.

Australian Design Rules (ADRs) for emissions control

Vehicle Standards, or Australian Design Rules (ADRs) are made under the Road Vehicle Standards Act 2018. Many ADRs are harmonised closely with international regulations, so that Australian’s can access similar vehicle choices to other international markets.

Vehicle Standard (Australian Design Rule 79/04 - Emission Control for Light Vehicles) 2011 applies to light vehicles approved for sale in Australia from 1 November 2016. ADR 79/04 prescribes the limits of noxious emissions allowed during standardised testing, and the standard test procedures for measuring these emissions, by adopting the requirements of the United Nations Economic Commission for Europe (UNECE) Regulation 83/06.

Many light vehicles in Australia comply with Australian Design Rule (ADR) 79/04, which is based on an international standards called ‘Euro 5’.

Internal combustion engine vehicles that comply with ADR 79/04 have performed a standard test procedure, which produces three figures for fuel consumption and CO₂ emissions - the ‘combined’, 'urban' (low speed) and 'extra-urban' (higher speed) values.

The combined CO₂ value is used to rank vehicles on the GVG website, and is also provided on the Fuel Consumption Label on the windscreen of new vehicles. A vehicle that uses more fuel will generally emit more CO₂.

Plug-in Hybrid Electric Vehicles (PHEVs) and Electric Vehicles (EVs) that comply with ADR 79/04 are not required to provide these three values for fuel consumption and CO₂. Some manufacturers may supply fuel consumption or CO₂ data for PHEVs in a ‘charge-depleting’ and ‘charge-sustaining’ test as urban and extra values. However, there is no requirement for this.

Some vehicles supplied to Australia comply with ADR 79/04, and meet tougher Euro 6 standards adopted in other countries.

• Euro 6 diesel vehicles emit less oxides of nitrogen (NOx) than Euro 5 diesel vehicles.
• Euro 6 petrol vehicles emit less fine particles than Euro 5 petrol vehicles.

New Australian Design Rules (ADRs) for emissions control

Three new ADRs based on the Euro 6d standards for light vehicles (cars, SUVs and light commercial vehicles) are being phased in for:

• newly approved light vehicle models first supplied to Australia from 1 December 2025; and
• all new light vehicles supplied to Australia on or after 1 July 2028.

The ADRs are based on international vehicle standards adopted by the United Nations. The new ADRs are:

• Vehicle Standard (Australian Design Rule 79/05 – Emission Control for Light Vehicles) 2024, based on UN Regulation 83/08.
• Vehicle Standard (Australian Design Rule 111/00 – Advanced Emission Control for Light Vehicles) 2024 , based on the improved laboratory tests for tailpipe emissions, evaporative emissions and durability adopted in UN Regulation 154.
• Vehicle Standard (Australian Design Rule 112/00 – Control of Real Driving Emissions for Light Vehicles) 2024, based on the on-road emissions testing requirements adopted in UN Regulation 168.

The new ADRs will also accept vehicles meeting the current US 'Tier 3' Standards for light duty vehicles. This is because US emission limits and durability requirements are compatible with those required by the Euro 6d standard.

Vehicles that comply with these new ADRs have performed a standard test-procedure known as the Worldwide harmonised Light vehicles Test Procedure (WLTP). The WLTP test procedure was introduced internationally through UN Regulation 154.

To ensure vehicles complying with new noxious emissions standards can comply with requirements for fuel consumption labelling, the Government has announced changes to fuel consumption labelling requirements to reflect the new test procedure. For more information on testing procedures for vehicle certification, and how these changes influence consumer information, please visit our Fuel Consumption Label page.