NPI Industry reporting
The aggregated emissions manuals complement the NPI Industry handbooks, and are intended to enable State and Territory Governments to estimate emissions from non-industrial activities (e.g. transportation, domestic and commercial activities) and emissions from industry which are not reported because the relevant thresholds are not exceeded.
A motor vehicle, for the purposes of this manual, is defined as an on-road vehicle that derives some, or part of, its power for propulsion from the combustion of fossil fuel. 'On-road vehicles' essentially include all vehicles that are intended for on-road use (including recreational four-wheel drive vehicles that may also be used off roads), but do not include vehicles designed exclusively for off-road use (e.g. construction vehicles).
The energy to propel the vehicle comes from burning fuel in an engine. Pollution from vehicles arises from the by-products of the combustion process (emitted via the exhaust system) and from evaporation of the fuel itself. Particulate matter is also emitted from brakes and tyre wear.
Various types of pollutants are produced in the combustion process. A range of volatile organic compounds (VOCs) are produced because the fuel is not completely burnt (oxidised) during combustion. Oxides of nitrogen (NOx) result from the oxidation of nitrogen at high temperature and pressure in the combustion chamber. Carbon monoxide (CO) occurs when carbon in the fuel is partially oxidised rather than fully oxidised to carbon dioxide. Sulphur dioxide (SO2) and lead are derived from the sulphur and lead in fuels. Particulate matter is produced from the incomplete combustion of fuels, additives in fuels and lubricants, and worn material that accumulates in the engine lubricant. These additives and worn materials also contain trace amounts of various metals and their compounds which may be released as exhaust emissions.
Evaporative emissions come mainly from petrol (diesel fuel has a much lower vapour pressure) and consist of VOCs and small amounts of lead. Evaporative emissions also occur from vehicle refuelling at service stations or from fuel tanker loading and unloading. These emissions can be estimated using the EET Manual for Aggregated Emissions from Service Stations, or will be estimated by reporting facilities as part of NPI reporting arrangements, and are not considered in this manual. Emissions can occur when liquid fuel leaks or is spilt, but these emissions are also not considered in this manual.
Another type of emission that arises from use of motor vehicles is dust emissions from roads. These emissions are covered in the EET Manual for Aggregated Emissions from Paved and Unpaved Roads and will also not be considered in this manual.
Finally, emissions from off-road vehicles, such as trail bikes, are also not covered in this manual.
First published in November 2000
National Pollutant Inventory
Environment Australia
The full document is available for downloading as a PDF file. You will need Adobe Acrobat Reader installed on your computer to view the PDF file.
If you are unable to access this document, please contact the Department of the Environment and Heritage to organise a suitable alternative format.
Each of the aggregated emissions manuals provides details of: