BULK STORAGE PLANTS

70-515 ARTICLE 515 - BULK STORAGE PLANTS 515-1. Definition. A bulk storage plant is that portion of a property where flammable liquids are received by tank vessel, pipelines, tank car, or tank vehicle, and are stored or blended in bulk for the purpose of distributing such liquids by tank vessel, pipeline, tank car, tank vehicle, portable tank, or container. (FPN): For further information, see Flammable and Combustible Liquids Code, NFPA 30-1990 (ANSI). 515-2.* Class I Locations. Table 515-2 shall be applied where Class I liquids are stored, handled, or dispensed and shall be used to delineate and classify bulk storage plants. The Class I location shall not extend beyond a floor, wall, roof, or other solid partition that has no communicating openings. (FPN): The area classifications listed in Table 515-2 are based on the premise that the installation meets the applicable requirements of Flammable and Combustible Liquids Code, NFPA 30-1990 (ANSI), Chapter 5 in all respects. Should this not be the case, the authority having jurisdiction has the authority to classify the extent of the classified space. 515-3. Wiring and Equipment Within Class I Locations. All electric wiring and equipment within the Class I locations defined in Section 515-2 shall comply with the applicable provisions of Article 501. Exception: As permitted in Section 515-5. 515-4. Wiring and Equipment Above Class I Locations. All fixed wiring above Class I locations shall be in metal raceways or PVC schedule 80 rigid nonmetallic conduit, or equivalent, or be Type MI, TC, SNM, or Type MC cable. Fixed equipment that may produce arcs, sparks, or particles of hot metal, such as lamps and lampholders for fixed lighting, cutouts, switches, receptacles, motors, or other equipment having make-and-break or sliding contacts, shall be of the totally enclosed type or be so constructed as to prevent escape of sparks or hot metal particles. Portable lamps or other utilization equipment and their flexible cords shall comply with the provisions of Article 501 for the class of location above which they are connected or used. 515-5. Underground Wiring. (a) Wiring Method. Underground wiring shall be installed in threaded rigid metal conduit or threaded steel intermediate metal conduit or, where buried under not less than 2 feet (610 mm) of earth, shall be permitted in rigid nonmetallic conduit or an approved cable. Where rigid nonmetallic conduit is used, threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for the last 2 feet (610 mm) of the conduit run to emergence or to the point of connection to the aboveground raceway. Where cable is used, it shall be enclosed in threaded rigid metal conduit or threaded steel intermediate metal conduit from the point of lowest buried cable level to the point of connection to the aboveground raceway. (b) Insulation. Conductor insulation shall comply with Section 501-13. 70-516 NATIONAL ELECTRICAL CODE Table 515-2.* Class I Locations - Bulk Plants Class I, Location Division Extent of Classified Location Indoor equipment installed in 1 Space within 5 feet of any edge of accordance with Flammable such equipment, extending in all and Combustible Liquids directions. Code, NFPA 30-1990 (ANSI), 2 Space between 5 feet and 8 feet of Section 5-3.3.2 where flamany edge of such equipment, mable vapor-air mixtures may extending in all directions. Also, exist under normal operation. space up to 3 feet above floor or grade level within 5 feet to 25 feet horizontally from any edge of such equipment.* Outdoor equipment of the type 1 Space within 3 feet of any edge of covered in Flammable and such equipment, extending in all Combustible Liquids Code, directions. NFPA 30-1990 (ANSI), Section 2 Space between 3 feet and 8 feet of 5-3.3.2 where flammable vaporany edge of such equipment, air mixtures may exist under extending in all directions. Also, normal operation. space up to 3 feet above floor or grade level within 3 feet to 10 feet horizontally from any edge of such equipment. Tank - Aboveground** 1 Space 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. Shell, Ends, or Roof and Dike 2 Within 10 feet from shell, ends, or Space roof of tank. Space inside dikes to level of top of dike. Vent 1 Within 5 feet of open end of vent, extending in all directions. 2 Space between 5 feet and 10 feet from open end of vent, extending in all directions. Floating Roof 1 Space above the roof and within the shell. Underground Tank Fill Opening 1 Any pit, box, or space below grade level, if any part is within a Division 1 or 2 classified location. 2 Up 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 Upward 1 Within 3 feet of open end of vent, extending in all directions. 2 Space between 3 feet and 5 feet of open end of vent, extending in all directions. *The release of Class I liquids may generate vapors to the extent that the entire building, and possibly a zone surrounding it, should be considered a Class I, Division 2 location. For Tanks - Underground, see Section 514-2. ARTICLE 515 - BULK STORAGE PLANTS 70-517 Table 515-2. Class I Locations - Bulk Plants (cont.) Class I, Location Division Extent of Classified Location Drum and Container Filling Outdoors, or Indoors with 1 Within 3 feet of vent and fill open- Adequate Ventilation ings, extending in all directions. 2 Space between 3 feet and 5 feet from vent or 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 openings. Pumps, Bleeders, Withdrawal Fittings, Meters and Similar Devices Indoors 2 Within 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. Outdoors 2 Within 3 feet of any edge of such devices, extending in all directions. Also up to 18 inches above grade level within 10 feet horizontally from any edge of such devices. Pits Without Mechanical 1 Entire space within pit if any part Ventilation is within a Division 1 or 2 classified location. With Adequate Mechanical 2 Entire space within pit if any part Ventilation is within a Division 1 or 2 classified location. Containing Valves, Fittings, or 2 Entire pit. Piping, and not within a Division 1 or 2 Classified Location Drainage Ditches, Separators, Impounding Basins Outdoor 2 Space up to 18 inches above ditch, separator, or basin. Also up to 18 inches above grade within 15 feet horizontally from any edge. Indoor Same as pits. Tank Vehicle and Tank Car* Loading Through Open Dome 1 Within 3 feet of edge of dome, extending in all directions. 2 Space between 3 feet and 15 feet from edge of dome, extending in all directions. *When classifying extent of space, consideration shall be given to fact that tank cars or tank vehicles may be spotted at varying points. Therefore, the extremities of the loading or unloading positions shall be used. 70-518 NATIONAL ELECTRICAL CODE Table 515-2. Class I Locations - Bulk Plants (cont.) Class I, Location Division Extent of Classified Location Loading through Bottom 1 Within 3 feet of point of venting to Connections with atmosphere, extending in all Atmospheric Venting directions. 2 Space 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 Rest Rooms Ordinary If there is any 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 1 Within 3 feet of open end of vent, Dome with Atmospheric extending in all directions. Venting 2 Space 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 2 Within 3 feet of point of connec- Dome with Vapor Control tion of both fill and vapor lines, extending in all directions. Bottom Loading with Vapor 2 Within 3 feet of point of connec- Control tions, extending in all directions. Any Bottom Unloading Also up to 18 inches above grade within a horizontal radius of 10 feet from point of connections. Storage and Repair Garage for 1 All pits or spaces below floor Tank Vehicles level. 2 Space up to 18 inches above floor or grade level for entire storage or repair garage. Garages for other than Tank Ordinary If there is any opening to these Vehicles rooms within the extent of an outdoor classified location, the entire room shall be classified the same as the space classification at the point of the opening. Outdoor Drum Storage Ordinary Indoor Warehousing Where Ordinary If there is any opening to these There is No Flammable rooms within the extent of an Liquid Transfer indoor classified location, the room shall be classified the same as if the wall, curb, or partition did not exist. Piers and Wharves See Figure 1. For SI units: one inch = 25.4 millimeters; one foot = 0.3048 meter. ARTICLE 515 - BULK STORAGE PLANTS 70-519 50' 50' 25' Deck 25' 25' Open sump in deck for Operating envelope draining lines and hoses and stored position of loading arms or hoses 1 Foot = 0.3 meters 50' 2' 25' Approach Pier Shore Water level Division 1 Division 2 Nonclassified Notes: (1) The "source of vapor" shall be the operating envelope and stored position of the outboard flange connection of the loading arm (or hose). (2) The berth area adjacent to tanker and barge cargo tanks is to be Division 2 to the following extent: a. 25 ft (7.6 m) horizontally in all directions on the pier side from that portion of the hull containing cargo tanks. b. From the water level to 25 ft (7.6 m) above the cargo tanks at their highest position. (3) Additional locations may have to be classified as required by the presence of other sources of flammable liquids on the berth, or by Coast Guard or other regulations. Figure 1.x Marine Terminal Handling Flammable Liquids. (c) Nonmetallic Wiring. Where rigid nonmetallic conduit or cable with a nonmetallic sheath is used, an equipment grounding conductor shall be included to provide for electrical continuity of the raceway system and for grounding of noncurrent-carrying metal parts. 515-6. Sealing. Approved seals shall be provided in accordance with