Open Cut » Health and Safety
Tyres, rims and wheel assemblies are safety critical items which must be maintained and used correctly to achieve levels of acceptable risk. Inadequate tyre and rim maintenance carries considerable inherent risks of personal injury and death, as tragically confirmed through several tyre and rim related fatalities in the Australasian region over the last few years, including some involving non-earthmoving equipment.
As such this project report aims to identify tyre maintenance safety issues around non-earthmoving vehicles and mobile equipment, and demonstrate effective solutions such as better tooling, improved maintenance equipment, improved safe work practises, and other recommendations for safer work.
Principle findings of the report are as follows:
· Australian mining industry relies heavily on rubber tyred equipment.
· In field observations suggest that there is a diverse range of non-earthmoving rubber tyred type equipment being used in Australian mines. This equipment can often be found in frontline applications such as long distance coal haulage. In some instances more than 50% of all rubber tyred equipment is non-earthmoving type equipment.
· Typical management of tyres, rims and wheels at mine sites is focussed largely around earthmover type tyres, rims and wheels. This bias seems to be driven by AS4457:2007-Part 1 which defines earthmoving machinery rim and wheel assemblies as units of 'not less than 24" (600 mm) in outside diameter'.
· There is no Australian or international standard providing any guidance (operational or maintenance) for rims and wheels of less than 24" (600mm) nominal diameter, i.e. those rims and wheels used for much of the non-earthmover ancillary rubber tyred equipment. Many of the company internal documents also seem to favour this distinction.
· Non-earthmover tyre and rim management receives much less management attention despite representing well over 50% of rubber tyred assets at some operations, and having been involved in several fatalities in the last few years.
· The design of non-earth moving equipment remains production focussed with less thought put into the maintainability of the equipment,
· Tyre maintenance relies heavily on standard type of tooling despite the increased frequency and therefore exposure to typical tyre maintenance hazards including considerable manual task hazards.
· Knowledge of sound solutions towards safer non-earthmover tyre maintenance is not consistently applied across industry.
Considering the above the following recommendations are made:
· All mine sites that utilise non-earthmoving type of equipment should review their risk assessments in light of this report; in particular sites should check and verify current controls for their effectiveness. Relevant procedures and processes must be amended where found wanting.
· Similarly sites should review tyre awareness and tyre maintenance training programmes for all mines personnel including contractors.
· The Australian Standard AS4457 should be amended to cover non-earthmoving tyres. This could be achieved through a general amendment of the '24 inch or 600 mm' outside diameter rule incorporating the standards other requirements, or through a separate standard covering specific sections (as applicable to non-earthmoving tyre equipment) such as:
- tyre and rim selection - to suit local haulage parameters,
- management of repaired tyres,
- pressure maintenance regimes,
- tyre and rim identification,
- training requirements,
- non-destructive testing of rims and wheels,
· Further research should be conducted in the area of design of mobile vehicle support systems - jacks and stands. The design must take into account the elimination of manual task hazards and resultant risks of placement and retrieval of jacks and stands from under the vehicle, including those created by a person's proximity to potentially damaged tyres and rims during that process. The design of' low profile lift and lock jacks' is encouraged to eliminate the need to place support stands.
· Research should also be carried out into developing a low profile jacking platform permanently placed into the laneway of the tyre maintenance bay.
· Designers of trailers should consider external jacking points to limit the requirement of manually placing jacks and stands under vehicles. Alternatively vehicle/trailer designers should consider inclusion of hydraulic or pneumatic jacks into the actual frame/chassis of the vehicle/trailer so they become self elevating without the need to place a jack/stand under the vehicle.
· All mine sites utilising non-earthmoving type of equipment should review tyre pressure recording, reporting/analysis and maintenance regimes. The use of independent tyre pressure monitoring and reporting systems is encouraged.