Small fire and minor injury during gas cutting

A member has reported an incident in which a small fire caused a minor injury during the use of oxyacetylene cutting equipment. The incident occurred when a welder was using the equipment to cut a piece of steel plate on the deck of the vessel. When the oxygen ran out the welder attached the regulator to a full bottle of oxygen. On reigniting the gas the oxygen failed to reach the flame. As the welder was attempting to diagnose the fault, the oxygen hose detached from the burner. There was a fire which burned through the leg of his overall and burned his thigh.

The fire watcher reacted promptly and switched off the gases at the bottles. This action quickly extinguished the fire and prevented any escalation. The welder was taken to a local hospital where his injuries were found to be minor and after treatment he was allowed back to work. His injuries could easily have been more serious.

An investigation revealed the following:

• The gas hoses were attached to the burner at check valves with crimped fittings;
• The oxygen check valve was damaged by the effects of the fire;
• The acetylene check valve was still connected to the hose. When the hose was removed it was found to have a deep score across the fitting (see image below). The damage was consistent with the blade of a hacksaw. It appears to have been caused when the hoses were being re-terminated. It was assumed that the oxygen fitting had similar damage which had added to the likelihood of its failure causing the gas release and fire;
• The equipment had been inspected and passed as fit for use by an external agency three weeks prior to the accident. The equipment was only inspected visually and the hoses were not removed to examine the fittings;
• The welder was wearing standard coveralls which were not sufficient to withstand the effects of the fire. He was wearing nylon jogging trousers under his coveralls which melted and added to his injuries.

It was noted that there was no specific procedure for the connection of regulators to gas bottles, maintenance of the cutting equipment or for the re-termination of the hoses. The following actions were taken:

• The burning equipment was replaced;
• Instructions were included so that when re-termination takes place, the check valve fittings should be replaced with new fitting;
• Welders are now required to wear protective overalls appropriate to their work and additional training for welders was provided.