Cleaner non-road diesel plant and equipment

Emissions from non-road diesel engines

Reducing exposure to diesel exhaust is an important public health and environmental issue.

Non-road diesel engines, such as dozers, graders, forklifts and tractors, have long working lives and are significant sources of fine-particle and nitrogen oxide (NOx) pollution in metropolitan areas and regional cities. Around 100,000 (or 15 per cent) of the nation's non-road engines are located in the NSW Greater Metropolitan Region (GMR) and around 9000 engines are purchased in the GMR every year. These engines account for about 5 to 10 per cent of fine particle pollution in the GMR and in some local government areas can contribute up to 45 per cent of fine-particle pollution.

At the local level, emissions from old engines can increase fine-particle concentrations to levels significantly higher than background levels. This leads to higher exposure to pollution and greater health consequences for workers and residents.

Health effects of diesel particulate pollution

Fine-particle emissions from diesel exhaust, most being particles under 2.5 micrometers in diameter (PM_2.5), are of particular concern because they can be inhaled deep into the lungs. Exposure to them is linked to premature death from heart and lung diseases, increased hospital admissions, asthma attacks, other respiratory symptoms and lost work days. There is no known safe threshold of exposure to PM_2.5.

Diesel exhaust emissions also contain other harmful pollutants, such as oxides of nitrogen (i.e. nitrogen dioxide and nitric oxide), which contribute to formation of ground-level ozone.

Emission standards

While on-road diesel engines sold in Australia, such as highway registered trucks and buses, are regulated to meet strict emission limits, there are no regulations or standards in place to control emissions from non-road diesel engines. A 2010 study (nonroaddieselrpt.pdf, 832KB) found that, nationally, the non-road diesel sector (excluding rail and marine transport) consumes a similar volume of automotive diesel oil as the on-road diesel vehicle sector. Regulated emissions limits for these engines have been enforced in the United States and the European Union since the mid-1990s and, more recently, in Canada, Japan, China and India.

The US Environment Protection Agency (US EPA) emission standards are expressed as tiers and European Commission (EC) standards are expressed as stages, with progressively tighter emission standards phased-in for different size engines. The graph shows the reduction in particle emissions as the US standards have become tightened over time from Tier 1 to Tier 4. Currently, all new diesel equipment must conform to Tier 3 or Tier 4 in the US and Stage IIIA or Stage IIIB within the European Union (see Emission standards for non-road diesel, Chapter 4 of the 2010 study for further details on US and EU emission standards).

A 2009 survey of new engines purchased in Australia indicates that around 80 per cent conformed to US EPA Tier 2 standard or below.

National work

NSW is working with Commonwealth and other state governments on national measures to support the supply and purchase of cleaner non-road diesel engines.

A 2010 study (nonroaddieselrpt.pdf, 832KB) to gather information and scope possible actions for cleaner new non-road diesel engines in Australia found significant health benefits can be achieved by implementing national standards for emissions from non-road diesel engines and equipment. The study was funded by NSW and the Commonwealth, and some of its findings were:

• particle-emission reductions achievable nationally by complying with the latest US standards are estimated to be between 5600 and 10,200 tonnes per annum in 2020, increasing to 7300 to 14,100 tonnes per annum in 2030
• annual health benefits associated with PM₁₀ and NO_x emissions reductions in Australia are estimated to be in the range $2.5 to $4.7 billion by 2030
• non-road diesel engines are all imported into Australia
• in the absence of national emissions standards, there is a risk that continued voluntary uptake of cleaner engines could decline in the face of cheaper, non-compliant imports, for some engine categories.

The report: Cleaner non-road diesel engine project - identification and recommendation of measures to support the uptake of cleaner non-road diesel engines in Australia (nonroaddieselrpt.pdf, 832KB) provides further details.

Strategies to reduce non-road diesel emissions

Developing a national approach to emissions from non-road diesel engines may be a lengthy process and national emissions standards will not address pollution from existing fleets, which have long working lives. It is therefore important to consider other strategies that will result in more immediate reductions in emissions from non-road diesel engines.

The amount of exhaust emitted by a diesel engine is related to the level (if any) of conformance to US/EU or other international emissions standards, its age, size and how well it is maintained and operated. The following strategies can be applied to reduce exposure to diesel exhaust emissions:

• purchasing engines that conform with the highest available US/EU standards (or other international standards)
• using cleaner, low sulfur fuels
• ensuring engines are correctly repaired and maintained
• improve an engine’s emission performance by fitting it with an exhaust-treatment device
• restricting unnecessary engine idling
• locating plant and equipment away from sensitive populations (e.g. schools, hospitals, child-care facilities) or using best-performing equipment near these areas
• locating plant and equipment away from residential areas and, when onsite work occurs near residential boarders, restricting access for non-essential vehicles and machinery
• avoiding the onsite use of diesel- or petrol-powered generators by substituting mains electricity or battery powered equipment where possible.

Clean machine pilot program

The NSW Office of Environment and Heritage (OEH) developed the Clean Machine Pilot Program, which incorporates some of the above measures to reduce diesel exhaust emissions. The program involves public organisations and private industry partnering with OEH to implement policies and strategies within the organisation that are aimed at reducing exposure to diesel exhaust emissions (in particular, particles).

Policies and strategies that may be implemented by the program partners include:

• ensuring new and hired equipment conforms to international emissions standards
• requiring contractors to use cleaner equipment where practicable
• implementing policies to reduce exposure to diesel emissions on worksites (such as reducing idling, ensuring equipment is correctly maintained and using cleaner equipment near sensitive populations)
• retrofitting older equipment with diesel particulate filters

OEH provides technical and financial assistance, including co-funding of 50 to 90 per cent for retrofits of qualifying machines (while funds are available). The program is flexible and partners take on elements of the program that suit their organisation.

For information on the Clean Machine Pilot Program, contact OEH on 131 555 or (02) 9995 5550. 

For information on other OEH clean air initiatives, visit Let's Clear the Air.