Near-miss: Dropped object – turnbuckle pin

  • Safety Flash
  • Published on 26 October 2012
  • Generated on 30 July 2026
  • IMCA SF 11/12
  • 2 minute read

A Member has reported a near miss incident in which a turnbuckle pin weighing approximately 2 kg fell more than 12 m to deck.

What happened?

The incident occurred on a third party construction support vessel used for pipe laying. The vessel has a gutter to guide the flexible pipe into the vertical tensioner. It is able to slew left and right to allow the flexible pipe to approach from various angles. This gutter was to be held in place using a combination of turnbuckle, chain and shackles (see photographs below.) Whilst installing the turnbuckle securing arrangement, the retaining pin of the turnbuckle was dropped more than 12m to deck. There were no injuries.

Using the DROPS Calculator as a benchmark in the classification of the potential consequences of a dropped object, our member determined that the outcome of dropping the turnbuckle pin could have resulted in a fatality

Location of turnbuckle pin

Location of turnbuckle pin

Where the turnbuckle pin fell from

Where the turnbuckle pin fell from

Securing of shackle pins used at height with wire

Securing of shackle pins used at height with wire

Securing of shackle pins used at height with wire

Securing of shackle pins used at height with wire

Securing of shackle pins used at height with wire

Securing of shackle pins used at height with wire

Our Member investigated the incident and as a result implemented a simple secondary securing method to prevent dropped objects.

Members may also find useful information from dropsonline.com.

Members’ attention is drawn to the following IMCA material which may be of assistance:

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