Here’s a simple explanation of each: Explosion Proof An Explosion Proof light is constructed with an outer housing of a sufficient enough structure such that WHEN an explosion occurs within the devise, the design of the housing retains the explosion long enough for the ignited materials to cool down to a temperature below the ignition point of the outside atmosphere.  Intrinsically Safe >An Intrinsically Safe light is independently certified to be incapable of generating enough heat, energy or spark to cause an explosion in the hazardous environment that it’s rated for, even if there’s a fault in the product.