Sierra Chemical Co. High Explosives Accident

On January 7, 1998, two massive explosions just seconds apart destroyed the Sierra Chemical Company’s Kean Canyon explosives manufacturing plant ten miles east of Reno, Nevada, killing four workers and injuring six others. The initial explosion occurred in a room where workers made “boosters” — small explosive devices used in the mining industry to detonate larger explosives.

A second, more powerful blast destroyed a building used for drying explosives, leaving a 40by-60-foot crater that was up to six feet deep. The two explosions destroyed buildings, blew down walls, and hurled debris as far as a thousand yards. Of the 11 Sierra employees who were at the site when the accident occurred, only one escaped without injury. The explosions killed all four workers who were in or near Booster Room 2, the production room where the first blast occurred.

In nearby Booster Room 1, one worker was blown 14 feet by the force of that initial blast. He and four others were trapped as the room collapsed, but all survived. The explosions had the force of a magnitude 2.0 earthquake and were felt some 20 miles away from the plant. Fearing further blasts, firefighters did not attempt to extinguish fires at the site, and the flames burned for more than a day. Sierra Chemical estimated that in all, 47,000 pounds of explosives were consumed during the accident. The facility was never rebuilt.