Heavy vehicle tyre inflation

Incident

21 December 2018

On Thursday 20 December 2018 WorkSafe ACT was called to a tyre fitting premises in Canberra where a 19 year old male was seriously injured when a tractor tyre that was being inflated exploded.

The man was knocked unconscious and suffered significant injuries including facial fractures and lacerations, multiple arm fractures, rib fractures and possible internal injuries.

Initial findings are that a protective cage/barrier was allegedly not used during inflation of the tyre.

It is important that cages/protection barriers are used when working with large tyres, such as those for some four wheel drives, trucks, tractors and other heavy vehicles.

Risks

Workers have been seriously injured or killed by blasted parts of a tyre and rim assembly or by the force of the sudden release of air pressure. Injuries have included permanent damage to hearing and eyesight.

Truck tyres are significantly larger and are designed to operate under higher pressure than regular car tyres, increasing the risk associated with an exploding tyre.

There are no circumstances under which maintenance should be carried out on a wheel while it has a tyre mounted on it under pressure, particularly any type of welding or wheel repair. Before any work is carried out on a wheel, you must ensure that the tyre has been completely de-pressurised by deflating the tyre and removing the core from the valve stem. Tyres should also be removed from the wheel to prevent damage during the repair.

Mitigating the risks

Only competent people should carry out repairs to a wheel. Any parts that are deemed unserviceable should be clearly labelled to prevent use and disposed of.

If you are a person conducting a business or undertaking (PCBU) where workers are required to repair, maintain or change heavy vehicle tyres, you must ensure that:

• an appropriate safe system of work is in place;
• workers are suitably trained and competent to perform the task;
• the wheel is inspected for damage and corrosion prior to refitting of tyres;
• tyres, whether new or used, are inspected for defects;
• tyre and rim assemblies are adequately secured in a safety cage or other portable restraint device prior to inflating the tyre;
• potential trajectory paths from a failure and exclusion zones have been identified;
• workers stand outside of the exclusion zones when seating a tyre bead and inflating tyres above 35 kPa or 5 psi;
• tyres are only inflated to the recommended pressure;
• the air hose between the clip-on valve nozzle and the remote gauge and trigger is long enough for workers to stay outside of the exclusion zone;
• a remote dump valve is also fitted that is capable of rapidly deflating the tyre in an emergency; and
• there are various types of tyre safety cages available. The PCBU must ensure that a safety cage that is appropriately designed and suitable for the tyre of tyre that is used for the task.

When maintaining or repairing heavy vehicle tyres or rims, you should deflate the tyres prior to removing from the vehicle. This does not apply to removing wheel tyre assemblies to facilitate other forms of maintenance such as tyre rotation, alignments or brake serving.

However, the wheel assembly should be thoroughly inspected for defects prior to removal.

The most common way to ensure a wheel is adequately secured before inflating is to use a tyre safety cage. The wheel is located in the centre of the cage preventing the wheel or tyre from being ejected in the event of an explosion.

Split rims are also common on heavy machinery. These introduce additional risks associated with over-inflation, incorrect fitment of parts, and failure of wheel components due to damage and corrosion.

Example of a tyre cage for light vehicle/ highway transport truck:

Example of a tyre cage for light heavy truck:

For further information contact WorkSafe ACT on 13 22 81 or email WorkSafe@act.gov.au.

This Alert contains information emerging during an investigation by WorkSafe ACT into the mentioned incident at the date of this report. The information contained in this report does not necessarily reflect the final outcome of WorkSafe’s views or proposed actions with respect to this incident. WorkSafe ACT does not warrant the information in this report is complete or up-to date and does not accept any liability to any person for the information in this report, or its use.