Managing high pressure fluids and gases

Background

The incidence of serious injury resulting from the uncontrolled release of high pressure hydraulic fluids is increasing. Recently, there has been one fatal accident and several serious injury incidents in New South Wales (see NSW Department of Primary Industries Safety Alerts SA05-13, SA05-15, SA06-16, SA06-18).

• SA05-13 – An employee sustained a hand injury (near miss hydraulic injection) while relieving stored hydraulic pressure through a bleed line adjacent to a longwall chock.
• SA05-15 – An operator sustained minor injuries when the hydraulic hose for the bucket tilt function burst, allowing pressurised fluid to smash the front windscreen of the front end loader he was operating.
• SA06-16 and SA06-18 – A contractor was fatally injured while taking fluid samples from a large hydraulic system used to power longwall machinery. The fatal injuries were consistent with hydraulic injection.

Hazards

While all of these incidents occurred under different circumstances, the common mechanism of injury was the uncontrolled release of high pressure hydraulic fluid. Recent reporting of high potential incidents (HPIs) in Queensland indicates that similar accidents are occurring through uncontrolled release of energy.

Discussion

All Queensland mines must recognise the hazards associated with high pressure fluids and gases, and manage these hazards appropriately as required by:

• Section 80 of the Coal Mining Safety and Health Regulation 2001 (fluid above and below atmospheric pressure) and
• Part 10 of the Mining and Quarrying Safety and Health Regulation 2001 (plant generally).

Compressed air jets, diesel fuel injectors and paint sprayers, as well as high pressure hydraulic systems, are only a few examples of items commonly found on a minesite, but all have the potential to inject fluid or gas under the skin and cause tissue damage. A mine's safety and health management system needs to identify all aspects of safely managing a high pressure fluid system as well as the treatment of any injuries that may result from a system malfunction.

A minesite response should contain, but is not limited to, the following:

• A risk-based management plan to address high-pressure fluids.
• A process for capturing information arising from unwanted releases of hydraulic fluid and dissemination of this information with the appropriate corrective actions identified.
• A training package for educating those who may be required to interact with high pressure hydraulic systems.
• Isolation processes that ensure high pressure systems are effectively depressurised to ensure all potential energy sources are neutralised.
• A review of current maintenance practices to incorporate all associated hydraulic components, including hoses, into a whole-of-life-cycle maintenance strategy.
• During the selection process for new or replacement machinery, or machinery undergoing overhaul or refurbishment, consideration needs to be given to the selection of proactive controls which reduce the hazards associated with an uncontrolled release of energy. e.g. work process checks to ensure effective depressurisation has been achieved, provision of anti-whip socks, segregation plates or barriers, and anti abrasion / diffusion covers.
• The traceability of hydraulic hoses through their operational life, utilising the manufacturer's specifications.
• Site protocols for the management of suspected fluid injection injuries.

The management of high pressure fluid injection injuries needs to highlight that such injuries may result in the amputation of the affected limb, body part or death if not appropriately treated.

Such a protocol should contain, but not be limited to, as least the following;

• Treating all possible fluid injection injuries as extremely serious or life threatening.
• Training site First Aiders in the appropriate response and treatment strategies.
• Providing emergency transport to hospital.
• Providing the attending medical professionals or institutions with Material Safety Data Sheets (MSDS) relating to the product suspected of being injected.
• Providing the medical institution that will be treating the patient with documentation that describes the time, date, circumstances and symptoms that have been observed while at site.
• Ensuring that medical institutions and professionals equipped with the appropriate expertise have been identified and are utilised when a fluid injection injury occurs.

When developing site protocols / management plans, the NSW Department of Primary Industries' MDG 41 - 'Guideline for Fluid Power System Safety at Mines' could be considered as a valuable reference tool.

Authorised by Brian Lyne - Chief Inspector of Mines

Contact: minesafetyandhealth@dnrm.qld.gov.au

Issued by Queensland Department of Mines and Energy