Skip to content

Lost time injury (LTI): Broken thumb

A member has reported an incident in which an employee suffered a broken thumb. The incident occurred during demobilisation works onboard a barge, where two technicians were stripping out cables and framework from within an electrical power distribution unit (PDU) container. During the final phase of the work, one of the technicians was removing a final horizontal section of ‘Unistrut’. Whilst supporting the left hand side of the Unistrut section with his left hand, he unscrewed the right hand screw. Unexpectedly, the right hand screw and Unistrut adaptor (ZEB) dislodged from its fixed position causing the right hand side of that section of Unistrut to fall to the ground. As he was still supporting the left hand end with his left hand and as the Unistrut fell, his thumb was caught within the section of Unistrut, twisting it and causing a broken thumb. First aid was provided onboard, after which he was taken to hospital for further treatment.

Unistrut and demonstrating how a thumb could become trapped within it
Unistrut and demonstrating how a thumb could become trapped within it

The company’s investigation revealed the following:

  • Risk assessments and toolbox talks were all in place prior to the incident;
  • All crew attended the pre-work briefing and toolbox talk;
  • Full appropriate personal protective equipment (PPE) was being worn, including suitable gloves;
  • The injured person did not feel ‘under pressure’ to get the task done too quickly;
  • The incident occurred near the end of the task;
  • There was insufficient appreciation of potential risks if a section of Unistrut detached unexpectedly. Had this potential been correctly identified it is unlikely that the incident would have happened; the risk assessment was not adequate.

It was noted that although the incident occurred during the removal of a section of Unistrut this could also happen during the installation of Unistrut. Actions identified are therefore as applicable to installation as to removal.

The primary action was to ensure that, henceforth, two people should be involved in the installation and/or removal of Unistrut sections, regardless of length. The second person should provide support to the Unistrut whilst it is being secured in position or removed to prevent any unexpected movement.

Safety Event

Published: 30 January 2013
Download: IMCA SF 03/13

IMCA Safety Flashes
Submit a Report

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of all. The effectiveness of the IMCA Safety Flash system depends on Members sharing information and so avoiding repeat incidents. Please consider adding [email protected] to your internal distribution list for safety alerts or manually submitting information on incidents you consider may be relevant. All information is anonymised or sanitised, as appropriate.

IMCA’s store terms and conditions ( apply to all downloads from IMCA’s website, including this document.

IMCA makes every effort to ensure the accuracy and reliability of the data contained in the documents it publishes, but IMCA shall 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.