Hanwha Aerospace explosion - what the follow-up inspection found

After a fatal explosion at an aerospace plant in South Korea, a three-month special inspection identified 473 safety and health violations, including uncertified equipment in explosion-risk areas, missing safety valves, absent leak detection and documentation deficiencies. The findings cut across nine independent barriers rather than one. One organisational finding stands out for operations: production and recruitment had increased while safety and health staffing had not. That makes scaling up a management of change question. When output rises, process equipment and logistics capacity get checked, but inspection, maintenance, Ex competence, supervision and emergency response rarely do.

Line drawing of a worker in a hard hat watching an explosion inside a process vessel as the lid is thrown open and debris and smoke are released.

Hanwha Aerospace explosion - what the follow-up inspection found

South Korea | CURRENT FOLLOW-UP | 1 October 2026

Following the June 2026 explosion at Hanwha Aerospace’s Daejeon plant, in which 5 workers were killed and 2 injured, South Korea’s Ministry of Employment and Labor conducted a special inspection lasting almost three months.

The scale of the findings is striking: inspectors identified 473 safety and health violations. Of these, 46 related specifically to explosion and fire hazards, and another 45 concerned hazardous substances and leakage risks.
Among the reported findings were:
* equipment without explosion-proof certification being used in explosion-risk areas;
* missing safety valves on equipment exposed to overpressure risk;
* missing leak-detection/alarm systems in areas handling toxic substances;
* deficiencies involving SDS/MSDS, training and Process Safety Management documentation.

There is also an important organisational finding: according to SBS, production and recruitment had increased, but safety and health staffing had not increased correspondingly.
The Ministry plans judicial action in 189 cases, while the other 284 cases are expected to result in fines totalling KRW 505.1 million.

What happened in the explosion?

The June accident reportedly occurred while workers were cleaning waste propellant sludge from equipment. That activity was identified through witness statements; the SBS report does not establish it as the final root cause, so that distinction is important.
The history is also significant: SBS reports fatal explosions at the same Daejeon plant in 2018 (5 deaths) and 2019 (3 deaths).

The Operational Ex lesson

This is much bigger than:
“Someone installed non-Ex equipment in a hazardous area.”
The inspection suggests failures across several independent barriers:
Hazardous material → containment → pressure protection → release detection → Ex equipment → procedures → competence → PSM → management resources.
And one finding deserves particular attention for Heads of Operations:
Production increased, but safety resources did not increase accordingly.

That is effectively an Operational Ex Management of Change question.
When production increases, we normally check capacity of:
process equipment → utilities → warehouse → logistics → manpower.
But do we also reassess capacity of: inspection → maintenance → Ex competence → housekeeping → supervision → safety engineering → PSM → emergency response?
If production changes but these resources remain static, the plant’s risk-control capacity per unit of production can decrease.

Read the SBS News report⁠ https://news.sbs.co.kr/english/article.do?news_id=N1008778980
Original article: https://news.sbs.co.kr/news/endPage.do?news_id=N1008778806

Hanwha Aerospace explosion - what the follow-up inspection found