Warning issued over mobile plant fires

WorkSafe Victoria recently issued a safety alert highlighting the danger of mine workers being exposed to mobile plant fires, following 23 incidents involving fire on mobile plant at mines in Victoria – 19 occurred in underground mines and four in open cut mines – since January 2010.

Typical causes of fire include component failure and/or inadequate maintenance, according to the safety alert, which noted that common contributing factors were failure to maintain: integrity of pressurised hydraulic hoses; hydraulic lines clear of heated surfaces (inadequate clearance or insulation); and sources of oil leaking onto hot engine components, among other factors.

The safety alert recommended a number of preventative control measures, and design preventative control measures included:

• Ensure hydraulic components are ‘like for like’ and considered suitable for use; always consult plant manufacturer before making changes
• Ensure any contractor installations/design modifications that are undertaken offsite are verified onsite by the employer before use and are equivalent to manufacturer’s standards and design
• Evaluate potential alternative higher flash point manufacturer-approved hydraulic oils, which contain Polyol Ester based fluids, phosphate esters or water glycol and emulsions. Such fluids must be compatible to the existing in situ components such as seals/fittings.

Installation preventative control measures included:

• Use fire resistant anti-static hoses whenever possible and consider high temperature tolerant hoses designed for oil operating temperatures greater than 150º Celsius
• Install and evaluate insulation around hot components or insulate hoses near hot components and upgrade to braided armour type hoses
• Ensure wiring is protected against fire, and connections are appropriate to manufacturer’s requirements and suitably located.

Inspection and maintenance preventative control measures included:

• Complete pre-start checks for locating and acting on oil leaks, sprays and stains.
• Use thermal imaging equipment to detect hot spots and high temperature areas of plant during maintenance programs.
• Routinely check solenoid connections for corrosion and replace/check at set engine hours or as per manufacturer recommendations. Consider protective devices for solenoids such as fuses.

Emergency response preventative control measures included:

• Install fire detection and automatic fire suppression on plant that is used in high risk zones and install engine auto-shutdown systems that operate when the fire suppression system is discharged.
• Ensure communication of fire-related events, maintenance incidents and subsequent attendance and associated follow-up is clear to employees