Murrin Murrin Operations fined $55,000

Murrin Murrin Operations Pty Ltd has been fined $55,000 after an incident where a worker was seriously injured.
Date: Wednesday, 10 October 2018

Murrin Murrin Operations Pty Ltd has been fined $55,000 in the Kalgoorlie Magistrates Court after an incident where a worker was seriously injured at its Murrin Murrin Cobalt-Nickel Operations located between Leonora and Laverton in the Eastern Goldfields.

On 13 July 2015, a worker was making safety preparations for maintenance on a piece of equipment known as a Treloar arm, used to unload liquid anhydrous ammonia.

In order to safely work on the Treloar arm, it needs to be purged of liquid anhydrous ammonia. This is done by feeding pressurised nitrogen into it through a flexible hose.

The worker was performing this task when the hose ruptured, allowing anhydrous ammonia to escape from the Treloar arm.

This formed a vapour that engulfed him and caused severe chemical burns to 20 per cent of his body.

In addition, he suffered acute swelling and inflammation of his throat and lungs that compromised his airways, requiring him to be resuscitated and subsequently hospitalised.

An investigation by the Department of Mines, Industry Regulation and Safety (DMIRS) found the condition of the hose used by the worker had deteriorated to a degree that the steel braiding beneath its rubber casing was exposed, and had become weakened by corrosion.

As a result, the hose was vulnerable to rupture when pressurised gas was fed through it.

Mines Safety Director Andrew Chaplyn said the company were aware of the hazardous nature of anhydrous ammonia, and the health and safety risks from hose failure.

"In 2010, an independent audit of hoses and fittings at the mine resulted in a series of recommendations that included monthly inspections to ensure hoses were fit for purpose and the removal of unserviceable hoses," Mr Chaplyn said.

The mine also had procedures for hoses used on hazardous duties. This included the requirement that hoses used for hazardous duties to be inspected and pressure tested quarterly, and that any hose that became defective … was to be deregistered, permanently withdrawn from use, and replaced.

“Despite having procedures in place, a significant number of hoses in use at the mine were not being maintained in accordance with those procedures,” Mr Chaplyn said.

"The mine's risk register also identified the potential for personal injury from the pressurised release of ammonia due to hose failure. In January 2015, six months before the incident, the mine issued a safety bulletin after a worker suffered a burn injury caused by the rupture of a defective hose.

"This incident was almost certainly avoidable. Had the procedures in place been implemented, the likelihood of workers being exposed to fugitive anhydrous ammonia as a result of hose rupture would have been practically eliminated."

Since the incident, the company has developed a new procedure which requires, among other things, applicable hoses to be inspected monthly by operations personnel, and inspected quarterly and pressure tested annually by a team of appointed competent maintenance personnel to verify their ability to perform to specification.

All hoses that fail inspection or testing are immediately withdrawn from service and replaced.

In handing down the penalty, the court took into account the company's early guilty plea and cooperation with investigators.