A survey was conducted relating to the current practices for the classification of hazardous locations in coal preparation plants. Several plants processing bituminous, anthracite, and lignite coal in Pennsylvania, West Virginia, North Dakota, Colorado, Montana, and Wyoming were visited. Coal preparation plant operations and designers as well as Mining Enforcement and Safety Administration (MESA) inspectors were interviewed. The National Electrical Code was discussed with selected members of a mine safety committee and electrical equipment manufacturers. Data provided by MESA on fire and explosion accidents in coal preparation plants were examined. The requirements of the pertinent federal regulations, National Electrical Code, National Electrical Manufacturers Association, and Underwriters' Laboratories were compared and evaluated. The report consists of two parts. Part I provides a summary of the findings and part II consists of recommended uniform guidelines that may be used for interpreting the National Electrical Code as it applies to the classification of hazardous areas in coal preparation plants.