Do you have any hazardous locations at your facility? In all likelihood, you do -- and you need specially rated electric motors & equipment when hazards are present. Here is a summary of what makes a location hazardous followed by an overview of the Class/Division and Zone approaches to classifying those locations.
What Makes a Location Hazardous?
A hazardous location is one where "explosion or fire hazards exist due to the presence of flammable gases, flammable or combustible liquid-produced vapors, combustible dusts, or ignitable fibers or flyings." Hazardous locations are classified based on likely ignitable concentration of combustible materials present at a location.
Depending on the type of hazard present and the risk level involved, there may be certain requirements that AC motors and DC motors have to meet in order to safely function. Also keep in mind that hazardous location requirements can involve both the type of motor that can be installed (e.g., explosion proof Siemens SIMOTICS) and the type of equipment that can be used with them (e.g., AEGIS shaft grounding ring).