Highly poisonous hydrofluoric acid leaked at Samsung Electronics's main chip plant in the South Korean city of Hwaseong on Thursday and injured three workers.
The memory chipmaker said "a small amount" of hydrofluoric acid leaked at around 11:30am Seoul time, when workers were upgrading parts of an existing facility, Samsung said on Thursday. This comes three months afterin January 2013, leaving four injured and one dead.
The injured workers are being treated for minor injuries at a nearby hospital, Samsung noted, adding it had reported the incident to the appropriate local authorities and was fully cooperating with investigations.
"We take the health and safety of workers very seriously and are committed to addressing any issues regarding the well-being of those working in our facilities," Samsung said.
However, the country's Ministry of Labor and Employment said Samsung Electronics had apparently not followed safety regulations, a separate report by Yonhap News noted.
According to the ministry, toxic hydrofluoric acid leaked from the same gas pipes which employees were repairing during January's incident. Hydrofluoric acid is a colorless acute poison which can damage the lungs and bones and even affect the nervous system.
Samsung has stepped up safety measures after the incident though. In March, the firm said it wouldand enhance safety checks.