Grain explosion at Nestle Purina plant injures four

A grain-dust explosion at a Flagstaff, Arizona Nestlé Purina plant injured four people on September 14, 2014.

The four contractors were doing welding work when the dust ignited, and the explosion blew out several metal doors and burned the contractors. All four were sent to the hospital, one with severe burns, according to reports. About 250 people work at the 70,000-square-foot plant.