Issues

• Climate Variability
• Enhanced Greenhouse Effect
• Ozone Depletion

• Meteorological Conditions
• Particulate Pollution
• Air Toxics
• Carbon Monoxide
• Heavy Industrial Emissions to Air
• Transport Emissions

• Commercial and Residential Indoor Air Quality

At a glance

The issue

Tasmania does not have sufficiently large urban centres for emissions to air from transport to be a major environmental concern, although such emissions are an important consideration in the total exposure of the population to air pollution. These transport-related emissions include carbon dioxide (CO₂) from the combustion of fuel, methane (CH₄) due to incomplete fuel combustion, and nitrous oxide (N₂O), which has increased due to the use of three-way catalytic converters. Other emissions include carbon monoxide (CO), sulphur oxides (SO_x), and non-methane volatile organic compounds (NMVOCs).

Several air pollutants are also associated with adverse health effects (see also Air Toxics Issue Report). Some volatile organic compounds are known carcinogens, notably benzene, while carbon monoxide, nitrogen oxides and sulphur oxides are also serious air pollutants. Some transport air emissions also contain lead (Pb) and fine particulate material (PM₁₀), both of which are associated with adverse health effects.

This 'At a glance' section provides an overview of transport emissions to air. More detailed information and references are available in the Transport Emissions Issue Report. An indicator on the Emission of Air Pollutants is included within the report.

A recommendation, outlining options to improve vehicle emissions, is also provided. A broader recommendation on Total Exposure to Air Pollution is also relevant to the issue of transport emissions.

Favourable news

• Use of unleaded petrol has increased steadily as the age profile of the vehicle fleet has changed.
   
• There has been a widespread move to introduce environmental management systems in the transport sector.
   
• Air emissions from mobile sources can be reduced by improving their maintenance, using cleaner fuels, improving fuel efficiency, employing stricter emission controls, and reducing the use of transport systems. Several of these approaches have associated economic benefits.
   
• Reductions in harmful air emissions are prompted by national programs to improve emission controls and fuel quality standards, and by greenhouse gas emission reduction requirements that Australia commits to undertake. Several national initiatives implemented in recent years to improve air emissions from the Australian transport sector have benefited Tasmania. These include the introduction of:
   
• lead replacement petrol;
   
• new Australian Design Rules for vehicle emission standards (introduced in 2002); and
   
• a 1997 Australian Government environmental strategy for the motor vehicle industry, primarily designed to encourage reduced fuel consumption.
   

Unfavourable news

• The State's vehicle fleet is not likely to compare well to other jurisdictions in the areas of fuel efficiency and vehicle maintenance. Diesel vehicle emissions are a particular problem, and it is common to encounter smaller vehicles with poor emission control systems, partly because Tasmania has a relatively old vehicle fleet.
   

Uncertain news

• There has been virtually no direct monitoring of transport emissions in Tasmania.
   


• The cumulative consequences of emissions from all sources are poorly understood but these need to be taken into account across regional centres and air sheds (areas that are defined by natural or topographical features affecting air quality).
   


• The geographically widespread nature of Tasmania's transport systems means that air emissions cannot easily be directly measured.
   

• Issue Report - continued in depth