That emphasizes the importance of bearing and seal maintenance for labeled Class II motors. Surface cleaning and winding thermostats can eliminate winding and frame overheating, but won't help the bearings.

Suppose the AHJ concludes that the location is not a Division 1 area? Here's how the NEC defines Division 2 (for Class I atmospheres): ". . . a location . . . in which volatile flammable liquids or flammable gases are handled, processed, or used, but in which . . . [they] . . . will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems, or in case of abnormal operation of equipment; or . . . in which ignitible concentrations. . . are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operation of the ventilating equipment; or . . . that is adjacent to a Class I, Division 1 location, and to which ignitible concentrations. . might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided.