Before going onto a tank: the UTK sampling explosion in Ulsan
An explosion and fire at a UTK storage tank on 10 February 2025 killed one person and injured another. Sampling requires coordination with the people controlling the tank.
What happened
Two external inspection workers were affected while working on the tank top. Newsis associated the work with product-quality inspection.
The specific ignition source was not established by this initial account.
Combine operations and inspection knowledge
Confirm the tank identifier, material, sampling point and stopping conditions together. Changes in transfer operations or nearby work can change the assessment; the inspector should not have to infer the tank’s state.
HSE · 설비 격리 / Safe isolation of plant and equipment
Check your workplace
- Is the tank and material positively identified?
- Could filling or transfer change the conditions?
- Can exposure be reduced by an engineered sampling method?
Reduce exposure before relying on personal precautions
Competent personnel should consider engineered sampling arrangements that reduce the need to open a tank or work on its roof. Do not improvise a sampling connection.
Equipment and protection need to suit the substance and location.
HSE · 설비 격리 / Safe isolation of plant and equipment
Stop and hand back clearly
Withdraw on unexpected leakage, an alarm or an unassessed operating change. Do not manipulate further fittings to investigate.
At completion, communicate reinstatement and the handling of remaining samples as well as the test result.
Putting it into practice
If transfer operations are proposed just before sampling, pause. Operations and inspection personnel reassess the conditions and communicate the decision before proceeding.
The cited HSE reference is UK guidance.
Technical insight
Sampling is an interface with the process
A short sampling task still needs review of tank contents and operating conditions. Assess access, the sampling point, any opening and nearby activity.
Define acceptable conditions and stop criteria for each sampling method. This can improve the local procedure without assuming an unconfirmed ignition source in the incident.
Korean safety resources
- KOSHA GUIDE C-C-6-2025 · Atmospheric storage tank inspection, alteration and repair
Sections 6–7 cover work permits and repair/alteration. Korean-language technical recommendations for atmospheric storage tanks.
- KOSHA · Practical safety handbook 57: Inorganic chemical manufacturing (2021)
Korean handbook: chemical plant fire/explosion/leaks p.166 and turnaround maintenance p.203. Prevention guidance, not an investigation of this incident.
Sources
- 뉴시스 · 울산 UTK 탱크 폭발·화재대한민국 / South Korea
- HSE · 설비 격리 / Safe isolation of plant and equipment영국 지침 / UK guidance