WSH: Two workers passed out and died in a dredger's ballast tank

  • Safety Flash
  • Published on 22 July 2021
  • Generated on 12 June 2026
  • IMCA SF 20/21
  • 2 minute read

The Workplace Safety and Health Council of Singapore (WSH) reported in Accident Notification of 24 May 2021, that two workers had passed out and died in a dredger’s ballast tank.

What happened?

A supervisor entered a dredging vessel’s ballast tank, which is a confined space, for an inspection. The supervisor entered the tank without any appropriate Personal Protective Equipment (PPE) and did not check if the confined space was safe. Shortly after entering, he collapsed and passed out.

After some time, another worker entered the tank in an attempt to rescue the supervisor, but also passed out upon entry. A third worker attempted a rescue as well, but he too collapsed inside the tank.

The rest of the crew subsequently introduced forced ventilation into the tank. The second worker eventually regained consciousness and managed to climb out of the tank. The supervisor and the third worker were later extricated by the Singapore Civil Defence Force but unfortunately did not survive.  This tragic accident highlights the invisible dangers of confined spaces. 

Supervisor entered a dredging vessel’s ballast tank, which is a confined space, for an inspection

Recommendations

The WSH recommendations are:

  • Do not open up any manhole into a confined space without proper authorisation.

  • Do not enter any confined space unless you have had appropriate training.

  • Do not attempt any rescue on your own without proper PPE.

Members should review:

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.