Coal Inspectorate | Alert | No.450 V 1 | 30 July 2024

Vehicle fault causing smoke at underground coal mines

What happened?

There have been two similar incidents in recent months at Queensland underground coal mines where smoke has started to come from a dry scrubber load haul dump (LHD).

No one was injured in these incidents but there is a serious risk that these machines - which are used throughout underground coal mining in Queensland - can catch on fire.

Key issues

• The diesel particulate matter (DPM) filter has been in service for over 80 engine hours.
• The DPM filter was heavily contaminated.
• The LHD uses a dry scrubber system as opposed to a wet scrubber system which does not have the same issues.
• The exhaust back pressure shut down system did not work as expected.

Recommendations

• First, contact the original equipment manufacturer (OEM) for dry scrubber explosion-proof diesel engine systems.
• Then review your mine’s risk assessment for that equipment (dry scrubber explosion-proof diesel engine systems).
• Confirm the operating capability of the exhaust back pressure shut down system.
• Now address the DPM filters. Contact your supplier of DPM filters to ensure the filters are suitable.
• Until the root cause of the exhaust back pressure shutdown system issues are identified by site and the OEM and rectified on dry scrubber LHDs, DPM filters should be replaced at a frequency not exceeding 48 calendar hours.
• Finally, comply with the requirements of Recognised Standard 3 - Explosion protected diesel engines.

References and further information

Recognised Standard 3: Explosion protected diesel engines