(C) POSCO E&C

Hydrofluoric acid (HF) was detected at the scene of the toxic gas leak accident at the POSCO Pohang Steelworks, which caused four casualties.

According to the police and other officials on the 7th, 2 ppm of hydrogen fluoride was detected at the pickling and annealing plant of the Stainless Steel (STS) rolling division where the accident occurred on the 5th. However, since the chemical component measurement was conducted about two hours after the accident, the exact amount and concentration of HF leaked at the time of the incident could not be confirmed.

Hydrofluoric acid (HF) is a colorless, irritating liquid that can cause damage to the skin and respiratory system upon exposure. The broken pipeline reportedly carried a liquid with a 55% HF content. The pipeline was made of plastic-based materials, such as Polyvinyl Chloride (PVC), which is relatively susceptible to breaking from external impact.

Police, in conjunction with the Ministry of Employment and Labor, the Daegu Regional Environmental Agency's Chemical Safety Management Team, and the Korea Occupational Safety and Health Agency, conducted a joint on-site investigation on the 6th. Based on the inspection results, they plan to determine the exact components of the leaked chemical substance and the cause of the incident.

The accident occurred around 8:50 AM on the 5th when four workers belonging to a subcontractor of POSCO DX were moving across the chemical pipeline to install an electrical cable, causing the pipeline to break.

As a result of the accident, one worker, Mr. A (54), was exposed to the hazardous chemical and later died after being transported to the hospital. Three other workers in their 20s and 30s suffered burns. The fire department confirmed that the chemical substance was only leaked inside the plant and subsequently carried out toxic substance removal operations on the day of the accident.