Mining industry injury renews old concerns over hydrocarbon use
Industry groups have expressed alarm at a recent Queensland incident prompted by the use of dubious refrigerant gas in a truck cabin.
A Resources Safety & Health Queensland (RSHQ) safety alert reports that, on January 11, a mine worker driving a truck in an underground mine suffered serious burns to their face, hands and chest as a result of an explosion in the truck cabin.
The worker’s eyes were protected from the blast by safety glasses.
The force of the blast blew some of the cabin windows clear of the truck.
While the investigation is still ongoing, the findings of the RSHQ investigation to date indicate that:
- The AC was charged with a refrigerant containing propane and isobutane (hydrocarbon) instead of compliance with the original equipment manufacturer (OEM) requirement which stipulates the use of R134a refrigerant
- The AC was not certified for the use of the hydrocarbon refrigerant
- Personnel servicing and charging the AC did not hold Queensland Gas Work Licences for working with hydrocarbon refrigerant
- The release of hydrocarbon refrigerant from the AC into the cab created an explosive atmosphere which was ignited by an unidentified source.
A similar incident occurred in 2014, when a drill operator in a coal mine suffered burns to the face, hands and torso in an explosion after hydrocarbon refrigerant leaked from the AC system and ignited, RSHQ notes.
RSHQ advises site senior executives must ensure that:
- They inspect all refrigeration plant and equipment including AC units on mobile plant to verify compliance with OEM guidance with regards to refrigerant(s)
- Any refrigeration plant and equipment charged with refrigerant(s) not specified by the OEM must be immediately quarantined from use
- If an alternate refrigerant is used, the refrigeration system must be inspected and certified for the use of that alternate refrigerant. In the case of hydrocarbon refrigerants, this is certified by the Petroleum and Gas Inspectorate
- Any refrigerants may only be charged or drained by persons that are specifically licensed for those refrigerants.
The incident evokes calls years ago from the Australian Trucking Association (ATA) that cheaper refrigerant gases have the potential to ignite in truck systems.
Read the warning the ATA issued in 2015, here
ATA chief engineer Bob Woodward says the major problem is that hydrocarbon refrigerants are very low cost and readily available, and perform until something in the system goes wrong.
“To our knowledge, no heavy vehicle refrigerant system in Australia has ever been designed to use these gases, and no matter the cost saving, they are definitely not worth the risk.
“Our recommendation is that operators never use cut-price re-gassing services and ensure that all air-conditioning and refrigeration systems in their fleet use the manufacturer’s recommended refrigerant gas product.”
The incident has also prompted a stern response from Australasia’s peak body representing the automotive air-conditioning, electrical and thermal management sector, the Vehicle Air-conditioning Specialists of Australasia (VASA).
VASA notes it has been warning and campaigning about the dangers of hydrocarbon refrigerant retrofits for more than two decades and is “saddened by the news” that a truck driver sustained serious injuries caused by a vehicle’s air-conditioning system being unlawfully charged with highly flammable non-standard hydrocarbon refrigerant.
“In that time there have been numerous serious injuries and deaths that would have been avoided if the air-conditioning and refrigeration systems had been using the correct non-flammable refrigerant or properly re-engineered with the necessary safeguards to mitigate the risk of using flammable refrigerant.”
It reiterates its position that hydrocarbon refrigerants must only be used in equipment and systems that were either originally designed for them or have been adequately converted to minimise the risk of leaks and ignition sources, adding that re-engineering an existing automotive system for hydrocarbon refrigerants is likely to be cost-prohibitive, and the repair and service of equipment and systems containing hydrocarbon refrigerant requires specific working practices to ensure safety.
VASA is “particularly discouraged” that the incident happened in Queensland, the only jurisdiction in Australia to impose specific controls over the use of hydrocarbon refrigerants.
“It is deeply concerning that this incident has occurred at an underground mining operation, a working environment requiring maintenance of the very highest of safety standards and yet this unfortunate situation still arose,” VASA president Ian Stangroome says.
“While VASA applauds the Queensland government for having numerous measures in place to prevent improper use of highly flammable hydrocarbon refrigerants, it seems that in this case the enforcement aspect has been lacking.
“Despite the extra precautions taken in Queensland, federal legislation means it is still possible for any unlicensed person to obtain hydrocarbon refrigerant and the necessary tools to set up shop without having to undergo the auditing requirements that apply to licensed air-conditioning and refrigeration businesses.
“However, it seems unlikely that a mining company would use an unlicensed backyard or DIY outfit for its vehicle maintenance.
“I can only imagine that perhaps a breach of trust has taken place between the mining company and its contractors or employees, in order for a vehicle to be sent underground after it has been illegally retrofitted to hydrocarbon refrigerants.”
Stangroome says those who sold hydrocarbon refrigerants to an ignorant marketplace and promoted them as a safe and compatible direct replacement for the product with which a vehicle or piece of equipment left the factory held a large portion of the responsibility for incidents such as this.
“Governments and industry need to do a better job of making people clear on their legal responsibilities, and what is or is not safe.”