CONROE, Texas - Investigators have confirmed that a massive explosion at a chemical plant warehouse in Conroe on Friday was accidental.
The Conroe Fire Department said 12 employees worked at the DrillChem plant in the 4300 block of North Loop 336.
According to investigators, the fire started in the southern end of the northernmost building. Possible causes of the explosion include electrical, gas-powered equipment, and spontaneous combustion caused by disposal of oily rags.
Fire officials are working to determine a main cause and said there is no concern that the public's safety has or will be compromised.
DrillChem officials are not ready to release the names of specific chemicals stored and used in the facility.
No one was injured. Everyone had left about an hour before the explosion, because they leave early on Friday.
The fire started Friday evening about 4:30 p.m.. It took firefighters about two hours to bring the blaze under control.
One firefighter suffered heat exhaustion and was transported to Conroe Regional ER.
Residents who live two miles or less from the plant were asked to turn off their air conditioners and stay indoors, but that shelter in place was lifted before 10 p.m. Friday.
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