Near miss: Worker temporarily trapped in confined space

  • Safety Flash
  • Published on 21 December 2017
  • Generated on 25 July 2026
  • IMCA SF 32/17
  • 2 minute read

On a vessel in a shipyard, a member of the painting team accessed a tank to perform an inspection. Around three hours later, a worker was assigned to close this tank, and this was done – but the painter was still inside.

What happened?

The painter only noticed he was trapped in the tank around 15 minutes after the manhole cover was closed. Fortunately, in less than an hour, personnel assigned to cleaning duties outside the tank’s surrounding could hear knocking sounds from inside the tank and called for assistance to investigate.

The manhole cover was opened, and the painter was able to exit the tank unharmed. Further check-ups with a doctor confirmed no impacts to his health and safety.

There was no valid permit to work (PTW) in place for the task, and hence there were no control measures in place, such as safe atmosphere monitoring, ventilation, or illumination

What went wrong? What were the causes?

  • There was no stand-by person outside the tank.

  • The painter entered the tank alone, even though the ‘buddy system’ was a practice expected by the shipyard.

  • The painter accessing the tank was a team leader and as such, had specific training for confined space entry, but still disregarded the implementation of control measures.

  • There was no valid permit to work (PTW) in place for the task, and hence there were no control measures in place, such as safe atmosphere monitoring, ventilation, or illumination.

Lessons learnt

A safety stand-down was led and conducted by the shipyard management with their employees. While this incident happened to shipyard workers during shipbuilding, the lessons learnt are applicable to all IMCA members operations.

This incident is under investigation and further updates may be communicated in future.

Members may wish to review the following IMCA documentation and safety promotional material:

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