Queensland Mines Inspectorate | Alert | No.389 V 1 | 01 April 2021

Hazards associated with some super large bore inflator adaptors

What happened?

On 25 August 2020 a Coal Mine Worker (CMW) was deflating an ultra-class rear dump truck tyre using a super large bore IN-80 inflator adaptor tool, also commonly known as a deflator tool (refer Figure 1). The stem of the inflator adaptor tool has ejected and struck the safety glasses being worn by the CMW. The CMW was startled by the impact and stumbled backwards off a step ladder, falling onto the workshop floor.

How did it happen?

• Whilst turning the handle of the inflator adaptor tool anti-clockwise to remove the valve core, the retaining collar has loosened and separated from the tool body and the stem has been ejected (refer Figure 2).
• The retaining collar of the adaptor tool involved in the incident had a right-hand thread, which when turned clockwise tightened the collar.
• Turning the adaptor tool handle anti-clockwise caused the collar to also turn anti-clockwise until it disengaged from the adaptor body and the stem ejected under the tyre air pressure.

Key issues

• Inadvertent unscrewing of IN-80 inflator adaptor retaining collars was identified by a tyre management company following a similar incident in 2017.
• At the time the tyre management company investigation identified that many experienced tyre fitters had experienced similar events and that the risks appeared to have been normalised and accepted by the workforce.
• The tyre management company worked with the supplier of the inflator adaptor. A safer replacement IN-100 tool for super large bores is available, replacing the IN-80 tool.
• NOTE: IN-80 and IN-100 inflator adaptor tools look the same (refer Figure 3).
• Site investigations confirmed that IN-80 tools are still being used by CMWs.
• Instead of ladders, fit for purpose work platforms should be used.

Recommendations

All mine SSEs should:

1. review site procedures for equipment used for inspecting, testing and maintaining plant,
2. verify the type of inflator adaptor tools in use across the site,
3. ensure inflator adaptor tools used at the mine are fit for purpose and cannot be inadvertently disassembled,
4. ensure personal tools used by CMWs are inspected and maintained on a regular basis,
5. consult with tool or service providers to identify and implement appropriately engineered and tamper proof solutions if required,
6. not rely on administrative controls to reduce the risk of collars being inadvertently unscrewed when inflator adaptor tools are in use,
7. ensure suitable work platforms are available and used for tasks where CMWs need to access plant above ground level.