Investigations are ongoing into an incident in which a worker was subjected to serious chemical burns at a processing plant after failure of a rubber hose.
Western Australia’s Department of Mines and Petroleum recently released a significant incident report, stating that a process worker was exposed below the waist to pressurised anhydrous ammonia at -33 degrees.
The worker was involved in a routine purging operation as part of scheduled maintenance of an ammonia storage area of a processing plant.
The worker connected a flexible rubber hose via coupling to a purge connection point, and the hose was charged with nitrogen as the valve was slowly opened, however the hose ruptured above the connection point, spraying the worker and enveloping him in a cloud of ammonia.
The worker was airlifted to “a city hospital” and treated for serious chemical burns.
DMP investigators said it appeared that repeated bending of the hose to less than its minimum design radius had damaged the steel braiding and inner rubber lining, rendering its condition unserviceable.
It was suggested that the loss of structural integrity of the hose had been difficult to visually identify.
The processing plant had experienced other hose failures in the past 12 months and implemented a training program to cover hose checks and removals from service.
The DMP report said it appeared that not all aspects of procedure relating to flexible hose safety had been followed when the hose was chosen for service.
The DMP has recommended care be taken when selecting hoses for use, that training programs and management systems should be implemented to ensure workers are educated about managing hose storage, inspections and maintenance, and that hoses deemed unserviceable should be taken out of service and discarded.