Near-miss: Release of trapped pressure after ROV dive

  • Safety Flash
  • Published on 6 October 2016
  • Generated on 11 June 2026
  • IMCA SF 26/16
  • 2 minute read

A Member has reported an incident in which there was an unplanned release of trapped pressure from part of the tooling frame under an ROV.

What happened?

The incident occurred when it was noted that the frame was not deploying correctly and was slightly twisted. Upon investigation the coil mounting frame had been fitted upside down. The crew began to remove the cross member using an Allen key to separate the frame into two sections for removal and to ease the handling during the turning over portion of the task.

Upon the first quarter turn of the port side Allen bolt, a hissing noise was heard. The supervisor immediately evacuated the area and had it barriered off.

Side bolt of tooling frame

The system was left to bleed down naturally. The risks of the job were re-assessed and additional personal protective equipment (PPE) was identified for further work in removing the frame.

Causal factors:

  • The potential for trapped pressure had not been identified.
  • The frame had been incorrectly fitted.

The following actions were taken:

  • An engineering solution was identified to prevent possibility of trapped pressure – holes drilled in cross-member.
  • Safety flash issued.
  • Other similar systems checked and modified as required.
  • Clear markings applied to ensure correct frame orientation.

Latest Safety Flashes:

Arm injury – need for focus on safe isolation and task control

A worker sustained an arm injury while troubleshooting a malfunctioning garbage compactor.

Read more
Floodlamp causes scaffold board to start smouldering

Workers on the accommodation deck noticed light smoke emanating from a nearby scaffold structure.

Read more
Lamp fixture fire in office cabin

A fire broke out in a ceiling lamp fitting in a cabin on a vessel.

Read more
BSEE: Prevent fires by inspecting cords, plugs and welding leads before use

The United States Bureau of Safety and Environmental Enforcement (BSEE) has published Safety Alert 515.

Read more
More positive stories

Some more stories of good things happening – what went right.

Read more

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.

The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.

All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.

IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.

The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.

Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.