The first fire occurred when a truck driver drove outside of a marked area and onto dry sulfate dust, which was ignited merely by the friction from the tires. This fire destroyed a dump truck and forced nearby buildings to have to evacuate.
The latest sulfur dust fire was caused when a sweeping machine made contact with something metal and created a spark, which ignited the flammable sulfur dust. Five people were hospitalized due to smoke inhalation from trying to fight the fire.
Sulfur dust can cause extra safety issues to firefighters because when the sulfur dust fire burns it creates hydrogen sulfide gas, which is toxic and flammable, and results in the dust having a lower flash point for explosion.
The firefighters used a drone to monitor hot spots in the piles of dust to prevent further flare-ups, and to track the plume of smoke to make sure it was not moving towards people. The facility has closed until a new water irrigation system and additional safety measures are installed, and are looking at extra corrective actions and working with local authorities to ensure future safety. The company will also switch to handling the dust by hand instead of with machinery that could cause sparks.