Article 515

Bulk Storage Plants

Informational Note: Text that is followed by a reference in brackets has been extracted from NFPA 30-2015, Flammable and Combustible Liquids Code. Only editorial changes were made to the extracted text to make it consistent with this Code.

515.1 Scope. This article covers a property or 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.

515.3 Class I Locations. Table 515.3 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 location shall not extend beyond a floor, wall, roof, or other solid partition that has no communicating openings. [30: 7.3, 7.4]

Informational Note No. 1: The area classifications listed in Table

1. are based on the premise that the installation meets the applicable requirements of NFPA 30 -2015, Flammable and Combustible Liquids Code, Chapter 5, in all respects. Should this not be the case, the authority having jurisdiction has the author‐ ity to classify the extent of the classified space.Informational Note No. 2: See 514.3(C) through (E) for gaso‐ line dispensing stations in marinas and boatyards.
2. Wiring and Equipment Located in Class I Locations. All electrical wiring and equipment within the Class I locations defined in 515.3 shall comply with the applicable provisions of Article 501 or Article 505 for the division or zone in which they are used.

Exception: As permitted in 515.8.

Table 515.3 Electrical Area Classifications

Location Division Zone Extent of Classified Area

Indoor equipment installed where flammable vapor–air mixtures can exist under normal operation (see Informational Note)

Outdoor equipment installed where flammable vapor–air mixtures can exist under normal operation

1 0 The entire area associated with such equipment where flammable gases or vapors are present continuously or for long periods of time

1. 1 Area within 1.5 m (5 ft) of any edge of such equipment, extending in all directions
2. 2 Area between 1.5 m and 2.5 m (5 ft and 8 ft) of any edge of such equipment, extending in all directions; also, space up to 900 mm (3 ft) above floor or grade level within 1.5 m to 7.5 m (5 ft to 25 ft) horizontally from any edge of such equipment1

1 0 The entire area associated with such equipment where flammable gases or vapors are present continuously or for long periods of time

1. 1 Area within 900 mm (3 ft) of any edge of such equipment, extending in all directions
2. 2 Area between 900 mm (3 ft) and 2.5 m (8 ft) of any edge of such equipment, extending in all directions; also, space up to 900 mm (3 ft) above floor or grade level within 900 mm to 3.0 m (3 ft to 10 ft) horizontally from any edge of such equipment
   Tank storage installations inside buildings11All equipment located below grade level
   22Any equipment located at or above grade levelTank — aboveground, fixed roof10Inside fixed roof tank
   11Area inside dike where dike height is greater than the distance from
   
   
   the tank to the dike for more than 50 percent of the tankcircumference22Within 3.0 m (10 ft) from shell, ends, or roof of tank; also, area
   
   
   inside dike to level of top of dike wall
   10Area inside of vent piping or opening
   11Within 1.5 m (5 ft) of open end of vent, extending in all directions
   22Area between 1.5 m and 3.0 m (5 ft and 10 ft) from open end of
   
   
   vent, extending in all directionsTank — aboveground, floating roof
   
   
   With fixed outer roof10Area between the floating and fixed roof sections and within the shellWith no fixed outer roof11Area above the floating roof and within the shellTank vault — interior11Entire interior volume, if Class I liquids are stored withinUnderground tank fill opening11Any pit, box, or space below grade level, if any part is within a
   
   
   Division 1 or 2, or Zone 1 or 2 classified location22Up to 450 mm (18 in.) above grade level within a horizontal radius
   
   
   of 3.0 m (10 ft) from a loose fill connection, and within a horizontal radius of 1.5 m (5 ft) from a tight fill connectionVent — discharging upward10Area inside of vent piping or opening
   11Within 900 mm (3 ft) of open end of vent, extending in all directions
   22Area between 900 mm and 1.5 m (3 ft and 5 ft) of open end of vent,
   Drum and container filling — outdoors or
   1
   0extending in all directionsArea inside the drum or container•
   
   indoors
   Pumps, bleeders, withdrawal fittings
   1. 1 Within 900 mm (3 ft) of vent and fill openings, extending in all directions
   2. 2 Area between 900 mm and 1.5 m (3 ft and 5 ft) from vent or fill opening, extending in all directions; also, up to 450 mm (18 in.) above floor or grade level within a horizontal radius of 3.0 m (10 ft) from vent or fill opening

Indoor 2 2 Within 1.5 m (5 ft) of any edge of such devices, extending in all directions; also, up to 900 mm (3 ft) above floor or grade level within 7.5 m (25 ft) horizontally from any edge of such devices

(continues)

Table 515.3 Continued

Location Division Zone Extent of Classified Area

Outdoor 2 2 Within 900 mm (3 ft) of any edge of such devices, extending in all directions. Also, up to 450 mm (18 in.) above grade level within

3.0 m (10 ft) horizontally from any edge of such devices

Pits and sumps

Without mechanical ventilation 1 1 Entire area within a pit or sump if any part is within a Division 1 or 2

or Zone 1 or 2 classified location

With adequate mechanical ventilation 2 2 Entire area within a pit or sump if any part is within a Division 1 or 2

or Zone 1 or 2 classified location

Containing valves, fittings, or piping, and not within a Division 1 or 2 or Zone 1 or 2 classified location

Drainage ditches, separators, impounding basins

2 2 Entire pit or sump

Outdoor 2 2 Area up to 450 mm (18 in.) above ditch, separator, or basin; also, area up to 450 mm (18 in.) above grade within 4.5 m (15 ft) horizontally from any edge

Indoor Same as pits and sumps

Tank vehicle and tank car2
Loading through open dome	1	0	Area inside of the tank
	1	1	Within 900 mm (3 ft) of edge of dome, extending in all directions
	2	2	Area between 900 mm and 4.5 m (3 ft and 15 ft) from edge of dome,

Loading through bottom connections with atmospheric venting

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Loading through closed dome with atmospheric

venting

extending in all directions

1 0 Area inside of the tank

1. 1 Within 900 mm (3 ft) of point of venting to atmosphere, extending in all directions
2. 2 Area between 900 mm and 4.5 m (3 ft and 15 ft) from point of venting to atmosphere, extending in all directions; also, up to 450 mm (18 in.) above grade within a horizontal radius of 3.0 m (10 ft) from point of loading connection

1. 1 Within 900 mm (3 ft) of open end of vent, extending in all directions
2. 2 Area between 900 mm and 4.5 m (3 ft and 15 ft) from open end of vent, extending in all directions; also, within 900 mm (3 ft) of edge of dome, extending in all directions

Loading through closed dome with vapor control 2 2 Within 900 mm (3 ft) of point of connection of both fill and vapor

lines extending in all directions

Bottom loading with vapor control or any bottom unloading

2 2 Within 900 mm (3 ft) of point of connections, extending in all directions; also up to 450 mm (18 in.) above grade within a horizontal radius of 3.0 m (10 ft) from point of connections

Storage and repair garage for tank vehicles 1 1 All pits or spaces below floor level

2 2 Area up to 450 mm (18 in.) above floor or grade level for entire storage or repair garage

Garages for other than tank vehicles Unclassified If there is any opening to these rooms within the extent of an

outdoor classified location, the entire room shall be classified the same as the area classification at the point of the opening.

Outdoor drum storage Unclassified

Inside rooms or storage lockers used for the storage of Class I liquids

2 2 Entire room or locker

(continues)

Table 515.3 Continued

Location Division Zone Extent of Classified Area

Indoor warehousing where there is no flammable liquid transfer

Unclassified If there is any opening to these rooms within the extent of an indoor classified location, the classified location shall extend through the opening to the same extent as if the wall, curb, or partition did not exist.

Office and rest rooms Unclassified 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.

Piers and wharves See Figure 515.3.

1The release of Class I liquids can generate vapors to the extent that the entire building, and possibly an area surrounding it, should be considered a Class I, Division 2 or Zone 2 location.

2When classifying extent of area, consideration shall be given to the fact that tank cars or tank vehicles can be spotted at varying points. Therefore, the extremities of the loading or unloading positions shall be used. [30:Table 7.3.3]

Informational Note: See Section 7.3 of NFPA 30-2015, Flammable and Combustible Liquids Code, for additional information.

50 ft

50 ft

25 ft 25 ft

Deck

25 ft

Open sump in deck for

draining lines and hose

Operating envelope

and stored position of loading arms or hose

50 ft

2 ft

25 ft

Approach

Pier

Shore

Key:

Division 1

Division 2

Nonclassified

Notes:

1. For SI units, 1 in. = 25 mm; 1 ft = 0.3 m.
2. The “source of vapor” is the operating envelope and stored position of the outboard flange connection of the loading arm (or hose).
3. The berth area adjacent to tanker and barge cargo tanks is to be Division 2 to the following extent:
   1. 25 ft (7.6 m) horizontally in all directions on the pier side from the portion of the hull containing cargo tanks.
   2. From the water level to 25 ft (7.6 m) above the cargo tanks at their highest position.
4. Additional locations can be classified as required by the presence of other sources of flammable liquids on the berth, or by Coast Guard or other regulations.

Water level

FIGURE 515.3 Area Classification for a Marine Terminal Handling Flammable Liquids. [30:Figure 29.3.22]

1. Wiring and Equipment Above Class I Locations.
   1. Fixed Wiring. All fixed wiring above Class I locations shall be in metal raceways, Schedule 80 PVC conduit, Type RTRC marked with the suffix -XW, or Type MI, Type TC, or Type MC cable, or Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, including installation in cable tray systems or Type ITC and Type ITC-ER cable as permitted in 727.4. The cable shall be terminated with listed fittings.
   2. Fixed Equipment. Fixed equipment that may produce arcs, sparks, or particles of hot metal, such as lamps and lamp‐ holders 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 constructed so as to prevent the escape of sparks or hot metal particles.
   3. Portable Luminaires or Other Utilization Equipment. Portable luminaires or other utilization equipment and their flexible cords shall comply with the provisions of Article 501 or Article 505 for the class of location above which they are connected or used.
2. Underground Wiring.
   1. 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 600 mm (2 ft) of cover, shall be permitted in Type PVC conduit, Type RTRC conduit, or a listed cable. Where Type PVC conduit or Type RTRC conduit is used, threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for not less than the last 600 mm (2 ft) of the conduit run to the conduit point of emergence from the underground location or to the point of connection to an 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.
   2. Insulation. Conductor insulation shall comply with 501.20.
   3. Nonmetallic Wiring. Where Type PVC conduit, Type RTRC 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 ground‐ ing of non–current-carrying metal parts.
3. Sealing. Sealing requirements shall apply to horizontal as well as to vertical boundaries of the defined Class I locations. Buried raceways and cables under defined Class I locations shall be considered to be within a Class I, Division 1 or Zone 1 location.
4. Special Equipment — Gasoline Dispensers. Where gasoline or other volatile flammable liquids or liquefied flam‐ mable gases are dispensed at bulk stations, the applicable provi‐ sions of Article 514 shall apply.

515.16 Grounding and Bonding. All metal raceways, the metal armor or metallic sheath on cables, and all non–current- carrying metal parts of fixed or portable electrical equipment, regardless of voltage, shall be grounded and bonded as provi‐ ded in Article 250.

Grounding and bonding in Class I locations shall comply with 501.30 for Class I, Division 1 and 2 locations and 505.25

for Class I, Zone 0, 1, and 2 locations.

Informational Note: For information on grounding for static protection, see 4.5.3.4 and 4.5.3.5 of NFPA 30 -2015, Flammable and Combustible Liquids Code.

Informational Note No. 2: Text that is followed by a reference in

brackets has been extracted from NFPA 33-2016, Standard for Spray Application Using Flammable and Combustible Materials, or NFPA 34-2015, Standard for Dipping, Coating, and Printing Processes Using Flammable or Combustible Liquids. Only editorial changes were made to the extracted text to make it consistent with this Code.

516.2 Definitions. For the purpose of this article, the follow‐ ing definitions shall apply.

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Limited Finishing Workstation. An apparatus that is capable of

Informational Note: See Section 14.3 of NFPA 33, Standard for

Spray Application Using Flammable or Combustible Materials, for limi‐ ted finishing workstations.

confining the vapors, mists, residues, dusts, or deposits that are generated by a spray application process but does not meet the requirements of a spray booth or spray room, as herein defined. [33:3.3.18.1]

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Membrane Enclosure. A temporary enclosure used for the spraying of workpieces that cannot be moved into a spray booth where open spraying is not practical due to the proxim‐ ity to other operations, finish quality, or concerns such as the collection of overspray.

Informational Note: See Chapter 18 of NFPA 33-2016, Standard for Spray Application Using Flammable or Combustible Materials, for information on the construction and use of membrane enclo‐ sures.

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Outdoor Spray Area. A spray area that is outside the confines of a building or that has a canopy or roof that does not limit the dissipation of the heat of a fire or dispersion of flammable vapors and does not restrict fire-fighting access and control. For the purpose of this standard, an outdoor spray area can be treated as an unenclosed spray area. [33:3.3.2.3.1]

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