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Diesel Emissions


We recognise that diesel emissions are an issue of community concern. Although locomotives used in the rail freight industry are a relatively minor contributor to overall diesel emissions (for example, locomotives contribute less than 1 per cent of Particulate Matter (PM)[1] in the greater Sydney, Newcastle and Wollongong regions, known collectively as the Greater Metropolitan Region), as a rail operator with a large diesel locomotive fleet we had taken a number of actions to effectively manage current and future emissions. Aurizon has taken these actions as part of a wider commitment by our company to operations that are sustainable and to building relationships with, and contributing as partners to the communities in which we operate.

Our initiatives to improve the air quality of our locomotive fleet include advanced driving methodologies, driver-assist technology, high specification (cleaner) diesel, and reduced locomotive idling time using Auto Engine Stop-Start.  In addition, we are in the process of implementing the Rail Industry Safety and Standards Board (RISSB) locomotive code of practice (see Case Study below) which is a freight rail industry led initiative focused on improving the air quality associated with Australia’s freight diesel locomotives.  The CoP became effective on the 1 December 2018.

Case Study - RISSB Code of Practice: Management of Locomotive Exhaust Emissions

Recognising community concern in relation to diesel emissions, Aurizon and other rail freight operators across Australia developed a voluntary industry led-approach to improving air quality associated with freight diesel locomotives.  Following a couple of years of development, this culminated in the publication of the Code of Practice for Management of Locomotive Exhaust Emissions (CoP) by RISSB in November 2017.

The CoP outlines emissions standards for new and existing fleet that must be met within 10 years of the effective date (1 December 2018). This represents a significant investment by freight rail operators in improving the management of locomotive emissions from existing and new fleet, which in turn contributes towards maintaining Australia’s excellent air quality standards.

The CoP provides that:

  • new locomotives acquired from 1 December 2018 will meet a standard for particulate matter emissions;
  • take action to reduce the particulate matter emissions of existing locomotives that exceed 0.30 g/kwh when these locomotives receive a major overhaul; and
  • each freight rail operator will submit an annual report on progress against the CoP.

In developing the CoP, we used an evidence-based approach focused on delivering sustainable and balanced environmental outcomes. As such, the CoP prioritises both particulate matter (PM) and greenhouse gas (GHG) emission reductions, while being careful not to decrease fuel efficiency in pursuit of greater nitrogen oxide reductions. This potentially negative impact was highlighted by the New South Wales Environment Protection Authority locomotive upgrade trial in 2015 that demonstrated that if PM and nitrogen oxide were both reduced, GHG emissions increased.

The full details of the Code of Practice are available here.