Explosion at Hanwha Aerospace Kills 5 in South Korea
According to the article the explosion happened when cleaners were trying to clean propellant residue off of tools of some kind. I would not be surprised to find out someone was cutting corners with safety:

Five people were killed Monday while two others were injured following an explosion at a Hanwha Aerospace factory in the central city of Daejeon, officials said.
Fire authorities received a report of the explosion at the defense company’s factory at 10:59 a.m., mobilizing some 100 personnel to put out a blaze at the site, according to the fire and police officials.
The explosion left five people dead and two people hurt — one with full-body burns and the other with minor injuries. The late victims were all found dead at the site. Two were contract employees in their 20s, while the others were permanent employees, with two in their 50s and one 30-something-year-old.
You can read more at the link.

