UK HSE: Workers injured by unplanned release of mud slurry

  • Safety Flash
  • Published on 1 June 2020
  • Generated on 20 June 2025
  • IMCA SF 17/20
  • 1 minute read

What happened?

An electricity power station company was prosecuted after three contractors were injured by a sudden release of water and sludge, while carrying out maintenance work.

Three crew were removing a recirculation pump for maintenance when approximately 39 cubic metres of diluted slurry and associated stored energy was released, while the pump was being removed.

The contractors were swept off the concrete plinth where they had been working and sustained multiple fracture injuries.

What were the causes? / What went wrong?

An investigation found that the pressurised contents of the pump and associated pipework had not been discharged prior to work starting, because the drain pipe was blocked.

This resulted in the release of stored energy during the removal of the pump, instead of during the isolation process.

There had been a failure to undertake a suitable and sufficient assessment of the hazards and risks associated with the work, and their employer had not implemented a safe system of work.

Latest Safety Flashes:

NTSB: Vessel crane contact with shore-side crane

The National Transportation Safety Board of the United States (NTSB) has published a report and an investigation.

Read more
Dropped pallet during forklift operation

A pallet containing a load weighing 500kg dropped off a flatbed truck in close proximity to a delivery driver.

Read more
Dropped object hazard: access hatch to the communication dome

During a routine scheduled safety inspection of the main mast, it was discovered that the access hatch to one of the communication domes had fallen off.

Read more
Lock out/Tag out and unauthorised electrical connections/disconnections
Read more
MAIB: Is your Lead-Acid battery safe?

The UK Marine Accident Investigation Branch has published Safety Digest 1/2025, consisting of lessons from recent Marine Accident Reports.

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.