A stuck pig is a changed condition: The Ulsan KET pipeline-cleaning fatality
A worker was reported killed during pipeline cleaning in Ulsan in January 2024. The case raises a practical question: what happens to stored pressure and potential projectiles when a cleaning pig stops moving?
What was reported
The incident involved a spherical cleaning pig in a buried-pipeline construction project. Reports associate the fatal injury with work to address a stuck pig.
The precise impact sequence—direct impact from the pig or impact involving a pipe component—requires further confirmation. The available accounts do not establish which object caused the fatal impact.
Treat a blockage as a change
A stalled pig is outside normal progress. It is a reason to stop and reassess, not to approach the outlet or improvise higher pressure.
The work team needs an identified decision-maker and a controlled exclusion area that considers both the pipe axis and potentially detached components.
HSE · 설비 격리 / Safe isolation of plant and equipment
Check your workplace
- Where is pressure verified?
- Who controls access near the outlet and fittings?
- Who reviews the method after a blockage?
Verify the isolated condition
Stopping the pressure source does not establish that every trapped section is depressurised. Follow the equipment-specific isolation and verification method selected by competent personnel.
Never loosen a flange as an improvised pressure test.
Communicate before restarting
Handovers should identify remaining pressure hazards, isolation points and access restrictions. Unexpected vibration or noise warrants withdrawal and reporting from outside the controlled area.
Resume only after the revised method has been communicated.
Putting it into practice
When the pig fails to arrive, stop the operation and keep people clear. The supervisor reviews the blockage and the verification method before authorising further work.
HSE guidance cited here is UK guidance, not a universal legal standard.
Technical insight
Treat a blockage as an abnormal condition
A stuck pig calls for reassessment of movement and discharge conditions. Increasing pressure is not merely a way to speed up routine work.
Define the point for stopping and reassessing, the exclusion arrangement and how pressure will be verified. Do not invent incident pressure or projectile trajectories for training.
Korean safety resources
- KOSHA GUIDE C-C-2-2025 · Chemical plant maintenance planning
Korean-language PDF on maintenance planning and preparation; technical recommendations.
Sources
- 한겨레 · 울산 KET 배관 세정 사망사고대한민국 / South Korea
- HSE · 설비 격리 / Safe isolation of plant and equipment영국 지침 / UK guidance