ULSAN — A fire accompanied by explosions at a chemical manufacturer in the Onsan National Industrial Complex in Ulju County, Ulsan, was brought under control in about four hours. Some 7,000 workers at a nearby construction site evacuated, but no injuries were reported.
The fire broke out at about 9:41 a.m. on the 14th at a chemical manufacturer in Haknam-ri, Onsan-eup, Ulju County, according to the Ulsan Fire Headquarters. Firefighters contained the main blaze at about 1:34 p.m., three hours and 53 minutes after it started.
The fire began as workers were transferring toluene, a Class 4 hazardous material stored in an 8,000-liter tank, through piping into 200-liter drums for shipment. The flames spread through drums in a nearby open yard to seven outdoor storage tanks holding toluene, thinner and acetone. Embers carried by the wind also ignited a separate fire on a lawn at an adjacent workplace.
Witnesses reported five to six explosions at the site, followed by flames and black smoke. A worker at a nearby plant said black smoke rose outside the window, and about a minute later there was an explosion strong enough to shake the building. The worker added that five to six more explosions followed at intervals of several minutes, and smoke covered the skies above the industrial complex.
Sixteen workers were reported inside the plant, though the National Fire Agency put the figure at 13; all evacuated on their own, and no one was hurt. But as black smoke and fumes spread and concerns grew over further explosions, part of the nearby S-Oil Shaheen Project Package 1 site halted work and evacuated about 7,000 workers. Employees at other nearby workplaces also moved to safety.
Firefighters arrived at the scene six minutes after receiving the report and began suppression work. As the risk of the fire spreading grew, authorities issued a Level 1 response at about 10:04 a.m., followed by a first and then a second national firefighting mobilization order from about 10:17 a.m. More than 200 personnel, three firefighting helicopters and the Central 119 Rescue Headquarters' high-volume water cannon system were deployed.
Local governments also took safety measures. Ulju County sent out a safety alert text message at 10:15 a.m., urging drivers to take detours and residents to stay cautious. The Ulsan city government fully blocked traffic along Dangwol-ro, Onsan-ro and Bangdo-ro to ensure a smooth supply of water for firefighting.
Police and fire authorities plan to investigate the exact cause of the fire and the extent of the damage once they finish extinguishing the remaining embers.