To understand grain dust explosions, it is helpful to understand the elements that make up the fire triangle and the explosion pentagon. Many people are familiar with the fire triangle of heat, fuel and oxygen. By removing one of the three elements of fire, you can prevent or put a fire out. OSHA says five elements must be present for a dust explosion to occur. They are heat, fuel, oxygen, dispersion of dust and confinement. Industry experts sometimes refer to this as the explosion pentagon. Like fire, if any of the 5 elements are removed, an explosion cannot occur.