5703.1.1 Classified locations for flammable liquids.
FC § 5703.1.1
Areas where flammable liquids are stored, handled or used, including the dispensing or mixing of such liquids, shall be in accordance with FC Table 5703.1.1 and the Electrical Code. A classified area shall not extend beyond any floor, roof or other solid partition having no openings. The extent of the classified area is allowed to be reduced, or eliminated, where sufficient technical justification is provided to the commissioner that a concentration in the area in excess of 25 percent of the lower flammable limit cannot be generated. FC Table 5703.1.1Class I Electrical Equipment Locations a LocationGroup D DivisionExtent of Classified AreaLocationGroup D DivisionExtent of Classified AreaUnderground tank fill opening1Pits, boxes or spaces below grade level, any part of which is within the Division 1 or 2 classified area.2Up to 18 inches above grade level within a horizontal radius of 10 feet from a loose-fill connection and within a horizontal radius of 5 feet from a tight-fill connection.Vent – Discharging upward1Within 3 feet of open end of vent, extending in all directions.2Area between 3 feet and 5 feet of open end of vent, extending in all directions.Drum and container filling Outdoor or indoor with adequate ventilation1Within 3 feet of vent and fill opening, extending in all directions.2Area between 3 feet and 5 feet from vent of fill opening, extending in all directions. Also up to 18 inches above floor or grade level within a horizontal radius of 10 feet from vent or fill opening.Pumps, bleeders, withdrawal fittings, meters and similar devices Indoor2Within 5 feet of any edge of such devices, extending in all directions. Also up to 3 feet above floor or grade level within 25 feet horizontally from any edge of such devices. Outdoor2Within 3 feet of any edge of such devices, extending in all directions. Also up to 18 inches horizontally from an edge of such devices.Pits Without mechanical ventilation1Entire area within pit if any part is within a Division 1 or 2 classified area. With mechanical ventilation2Entire area within pit if any part is within a Division 1 or 2 classified area. Containing valves, fittings or piping, and not within a Division 1 or 2 classified area2Entire pit.Drainage ditches, separators, impounding basins Indoor 1 or 2 Same as pits. Outdoor 2 Area up to 18 inches above ditch, separator or basin. Also up to 18 inches above grade within 15 feet horizontal from any edge. Cargo tank and tank car b Loading through open dome 1Within 3 feet of edge of dome, extending in all directions. 2Area between 3 feet and 15 feet from edge of dome, extending in all directions. Loading through bottom connections with atmospheric venting 1Within 3 feet of point of venting to atmosphere, extending in all directions. 2Area between 3 feet and 15 feet from point of venting to atmosphere, extending in all directions. Also up to 18 inches above grade within a horizontal radius of 10 feet from point of loading connection. Office and restrooms Ordinary Where there is an opening to these rooms within the extent of an indoor classified location, the room shall be classified the same as if the wall, curb or partition did not exist. Loading through closed dome with atmospheric venting1Within 3 feet of open end of vent, extending in all directions.2Area between 3 feet and 15 feet from open end of vent, extending in all directions. Also within 3 feet of edge of dome, extending in all directions. Loading through closed dome with vapor control2Within 3 feet of point of connection of both fill and vapor lines, extending in all directions. Bottom loading with vapor control or any bottom unloading2Within 3 feet of point of connection, extending in all directions. Also up to 18 inches above grade within a horizontal radius of 10 feet from point of connection.Repair garage for cargo tanks1Pits or spaces below floor level.2Area up to 18 inches above floor or grade level for entire storage or repair garage.Garages for other than cargo tanksOrdinaryWhere there is an opening to these rooms within the extent of an outdoor classified area, the entire room shall be classified the same as the area classification at the point of the opening.Outdoor drum storageOrdinaryIndoor warehousing where there is no flammable liquid transferOrdinaryWhere there is an opening to these rooms within the extent of an indoor classified area, the room shall be classified the same as if the wall, curb or partition did not exist.Indoor equipment where flammable vapor/air mixtures could exist under normal operations1Area within 5 feet of any edge of such equipment, extending in all directions.2Area between 5 feet and 8 feet of any edge of such equipment, extending in all directions. Also, area up to 3 feet above floor or grade level within 5 feet to 25 feet horizontally from any edge of such equipment. cOutdoor equipment where flammable vapor/air mixtures could exist under normal operations1Area within 3 feet of any edge of such equipment, extending in all directions.2Area between 3 feet and 8 feet of any edge of such equipment extending in all directions. Also, area up to 3 feet above floor or grade level within 3 feet to 10 feet horizontally from any edge of such equipment.Tank – Aboveground Shell, ends or roof and dike area 1 Area inside dike where dike height is greater than the distance from the tank to the dike for more than 50 percent of the tank circumference. 2 Area within 10 feet from shell, ends or roof of tank. Area inside dikes to level of top of dike. Vent 1 Area within 5 feet of open end of vent, extending in all directions. 2 Area between 5 feet and 10 feet from open end of vent, extending in all directions. Floating roof1Area above the roof and within the shell. For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm. a. Locations as classified in the Electrical Code. b. When classifying extent of area, consideration shall be given to the fact that tank cars or cargo tanks can be situated at varying points. Therefore, the perimeter of the loading or unloading positions shall be used. c. The release of Class I liquids can generate vapors to the extent that the entire building, and possibly a zone surrounding it, are considered a Class I, Division 2 location.
