FLAGSTAFF, Ariz. (AP) -- Flames from welding equipment touched off a grain-dust explosion at a Nestlé Purina plant in Flagstaff Sunday, burning two workers severely and leaving two others with less serious burns.
The four contractors were welding about 5 p.m. on the fifth floor of the complex's seven-story grain elevator when their torches sparked grain dust and set off the blast.
Flagstaff Fire Department Capt. Bill Morse said one man was severely burned and taken by air ambulance to the Arizona Burn Center at Maricopa Medical Center in Phoenix, and another man with severe burns was transported by ground ambulance to the same center.
Two others were taken to Flagstaff Medical Center.
The explosion did not produce a long-lasting fire but it blew out metal doors at the front of the grain elevator.
"Nestlé Purina has a very positive safety record and this is the first such incident at the plant in the over four decades of operation," according to a statement from the Flagstaff Fire Department.