“Even though the number of mine-owned machines compared to hire company-owned machines is approximately 50:50, mine-owned machines accounted for about 75% of all failures reported,” the mine safety branch of NSW Trade and Investment said.

A key finding from the review, which was undertaken by consultancy Shakti Corporation, was that reported ExDES failures in the state’s coal industry fell by 21% year-on-year to 130 in 2014.

This improvement could perhaps provide a counter argument to views that safety standards go more out the window during margin-squeezed coal price downturns.

However, T&I did not want the results to create any complacency.

“While a reduction of in-service failures is encouraging, the high potential risk of ExDES equipment operating in a non-explosion-protected condition cannot be understated,” it said.

“The need for continuous improvement in this area remains.”

Other standout findings included that pneumatic/hydraulic control system failures accounted for 40% of all Ex-DES failures (52 of the total) with nearly half of them due to valve or sensor faults with “circuit contamination also a significant factor”.

Fixed connections, mainly relating to fasteners, gaskets and the surface flatness of joint surfaces, caused 29% of the Ex-DES failures while exhaust flame trap issues were blamed for 16%.

“Of that, carbon build up was the most significant factor but generally maintenance-related issues featured strongly,” T&I said regarding the flame trap problems.

Nine maintenance-related recommendations were made to the coal industry with the full report available at the T&I website here.