Accident involving unguarded riddle on multipurpose fishing vessel Sian Elizabeth with 1 person injured

Location: 3 miles north of Kings Lynn, England.

Accident Investigation Report 3/2007

Read our marine accident investigation report, which includes what happened, actions taken and subsequent recommendations:

SianElizabethReport.pdf (1,613.17 kb)

Annexes (4,214.88 kb)


The 14m fishing vessel Sian Elizabeth departed from the Fisher Fleet in Kings Lynn at 1100 on 14 September 2006 in fine weather, having landed the previous catch. The vessel sailed, with three crew on board, to return to the cockle beds west of Hunstanton. A 17 year old, untrained crewman had joined Sian Elizabeth the previous day, this being his first job since leaving school. Shortly after the start of dredging, the untrained crewman started to clear the cockles from the chute into the hold as he had the previous day. As he was scraping the cockles down the chute with his right hand, he placed his left hand on the riddle frame assuming there was enough space to grip between the supporting frame and the rotating drum. The unguarded riddle construction formed a shear trap that caught the crewman’s left thumb and pulled his left arm into the riddle, causing serious injury.

Safety Issues

  • the construction and location of the riddle created a significant shear trap risk to crew routinely working in close proximity to the unguarded machinery
  • the risk of personal injury from routine working close to the riddle had not been effectively assessed
  • the owner’s delegation of responsibility for his vessels to individual skippers did not ensure compliance with the Code of Practice for the Safety of Small Fishing Vessels
  • the owner and skipper were unaware of the regulations governing employment of young persons
  • the deficiencies identified on board Sian Elizabeth during the MAIB investigation showed that a risk assessment had not been completed, annual self certification of the vessel had not been carried out, and the crew had not completed the required training


Recommendations have been made to the Maritime and Coastguard Agency and John Lake (Shellfish) Ltd.

This report was published on 12 March 2007.

Published 23 January 2015