The workers appeared to have inhaled nitrogen gas while performing safety checks in an underground cable room at the Gori plant near the southeastern port city of Busan, Korea Hydro and Nuclear Power (KHNP) said, adding that no radioactive leaks had been reported.
"They were found unconscious and pronounced dead after being sent to hospitals for treatment," a KHNP spokesman said .... http://timesofindia.indiatimes.com