A steam drain line modification, which was not documented or subject to a risk assessment, contributed to an accident on an oil tanker which resulted in burns to three crew members, an ATSB final report details.

On 6 May 2025, an engineering team was conducting maintenance on the main deck steam valve for the heating system of the oil tanker Wisdom Venture, while it was drifting off Sydney.

After the system was isolated, the team removed the valve bonnet, and residual hot condensate was suddenly released, resulting in burn injuries to three crew members.

After receiving first aid on board, the crew members were transported to shore for medical treatment.

An investigation by the ATSB found the crew had not allowed adequate time for the steam system to cool before commencing work on the cargo heating system main deck steam valve.

The investigation also found a permanent modification to the steam drain line had been implemented on board Wisdom Venture without documentation.

“This undocumented change, which was not incorporated into a risk assessment or formally reviewed, likely introduced a system vulnerability that undermined the effectiveness of the steam system isolation,” Chief Commissioner Angus Mitchell said.

Moreover, the ATSB found the modification was not identified during routine technical inspections or multiple company superintendent visits to the ship.

“This resulted in the management of change framework, which required any system modification to be subject to a formal risk assessment and documentation, not being effectively applied,” Mr Mitchell said.

Since the incident, the ship’s manager advised that the drain line on Wisdom Venture had been returned to its original design configuration.

The manager has also initiated a fleetwide campaign to identify any unauthorised modifications to shipboard piping systems.

Ship staff will also be reminded that all modifications must be undertaken in consultation with the company, in accordance with its management of change process.

Mr Mitchell said the accident highlights the critical importance of adhering to established safety and management of change procedures.

“Where changes are to be made to a system, these need to be recorded and the processes to identify the risks need to be followed to ensure there are no unintended consequences,” Mr Mitchell said.

“In addition, operators are reminded that maintenance involving steam systems must allow sufficient cooling time and include visual confirmation of isolation.”

Read the final report: Crew injuries during maintenance in engine room of Wisdom Venture, near Sydney, New South Wales, on 6 May 2025

Do you have info to share with us ? Suggest a correction