Subchapter A. GENERAL PROVISIONS

§ 13.1. Relative location to property.

 (a)  Tables. The following tables apply to relative location to property lines, public ways and other property:

   (1)  Aboveground tanks for the storage of flammable or combustible liquids, except those liquids with boilover characteristics and unstable liquids, operating at pressures not in excess of 2-1/2 psig and equipped with emergency venting which do not permit pressures to exceed 2 1/2 psig shall be located in accordance with the following table:

TABLE 1

Type of Tank	Protection	Minimum Distance in Feet From Property Line Which May be Built Upon, Including the Opposite Side of a Public Way	Minimum Distance in Feet From Nearest Side of Any Public Way or Nearest Building on Same Property (See Note)
Floating roof	Protection for exposures	1/2 times diameter of tank but need not exceed 90 feet	1/6 times diameter of tank but need not exceed 30 feet
	None	Diameter of tank but need not exceed 175 feet	1/6 times diameter of tank but need not exceed 30 feet
Vertical with weak roof to shell seam	Approved foam or inerting system on the tank	1/2 times diameter of tank but need not exceed 90 feet and shall not be less than 5 feet	1/6 times diameter of tank but need not exceed 30 feet and shall not be less than 5 feet
	Protection for exposures	Diameter of tank but need not exceed 175 feet	1/3 times diameter of tank but need not exceed 60 feet
	None	2 times diameter of tank but need not exceed 350 feet	1/3 times diameter of tank but need not exceed 60 feet
Horizontal and vertical with emergency relief venting to limit pressures to 2½ psig	Approved inerting system on the tank or approved foam system on vertical tanks	1/2 times Table 5 but shall not be less than 5 feet	1/2 times Table 5 but shall not be less than 5 feet
	Protection for exposures	Table 5	Table 5
	None	2 times Table 5	Table 5

   
NOTE—No pump or tank shall be placed within the legal right-of-way limits of any State highway or any highway under the jurisdiction of DOT.

   (2)  Aboveground tanks for the storage of flammable or combustible liquids, except those liquids with boilover characteristics and unstable liquids, operating at pressures exceeding 2½ psig or equipped with emergency venting which will permit pressures to exceed 2½ psig shall be located in accordance with the following table:

TABLE 2

Type of Tank	Protection	Minimum Distance in Feet From Property Line Which May be Built Upon, Including the Opposite Side of a Public Way	Minimum Distance in Feet From Nearest Side of Any Public Way or Nearest Building on Same Property (See Note)
Any type	Protection for exposures	1 1/2 times Table 5 but shall not be less than 25 feet	1 1/2 times Table 5 but shall not be less than 25 feet
	None	3 times Table 5 but shall not be less than 50 feet	1 1/2 times Table 5 but shall not be less than 25 feet

   
Note—No pump or tank shall be placed within the legal right-of-way limits of any State highway or any highway under the jurisdiction of DOT.

   (3)  Aboveground tanks for the storage of flammable or combustible liquids with boilover characteristics shall be located in accordance with the following table:

TABLE 3

Type of Tank	Protection	Minimum Distance in Feet From Property Line Which May be Built Upon, Including the Opposite Side of a Public Way	Minimum Distance in Feet From Nearest Side of Any Public Way or Nearest Building on Same Property (See Note)
Floating roof	Protection for exposures	Diameter of tank but need not exceed 175 feet	1/3 times diameter of tank but need not exceed 60 feet
	None	2 times diameter of tank but need not exceed 350 feet	1/3 times diameter of tank but need not exceed 60 feet
	Approved foam or inerting system	Diameter of tank but need not exceed 175 feet	1/3 times diameter of tank but need not exceed 60 feet
Fixed roof	Protection for exposures	2 times diameter of tank but need not exceed 350 feet	2/3 times diameter of tank but need not exceed 120 feet
	None	4 times diameter of tank but need not exceed 350 feet	2/3 times diameter of tank but need not exceed 120 feet

   
Note—No pump or tank shall be placed within the legal right-of-way limits of any State highway or any highway under the jurisdiction of DOT.

   (4)  Aboveground tanks for the storage of unstable liquids shall be located in accordance with the following table:

TABLE 4

Type of Tank	Protection	Minimum Distance in Feet From Property Line Which May be Built Upon, Including the Opposite Side of a Public Way	Minimum Distance in Feet From Nearest Side of Any Public Way or Nearest Building on Same Property (See Note)
Horizontal and vertical tanks with emergency relief venting to permit pressure not in excess of 2½ psig	Tank protected with any one of the following: approved water spray, approved inerting, approved insulation and refrigeration, approved barricade	Table 5 but not less than 25 feet	Not less than 25 feet
	Protection for exposures	2 1/2 times Table 5 but not less than 50 feet	Not less than 50 feet
	None	5 times Table 5 but not less than 100 feet	Not less than 100 feet
Horizontal and vertical tanks with emergency relief venting to permit pressure over 2½ psig	Tank protected with any one of the following: approved water spray, approved inerting, approved insulation and refrigeration, approved barricade	2 times Table 5 but not less than 50 feet	Not less than 50 feet
	Protection for exposures	4 times Table 5 but not less than 100 feet	Not less than 100 feet
	None	8 times Table 5 but not less than 150 feet	Not less than 150 feet

   
Note—No pump or tank shall be placed within the legal right-of-way limits of any State highway or any highway under the jurisdiction of DOT.

   (5)  The minimum distance used in Tables 1, 2, and 4 is set forth in the following table:

TABLE 5

Capacity of Tank (in gallons)	Minimum Distance in Feet From Property Line Which May be Built Upon, Including the Opposite Side of a Public Way	Minimum Distance in Feet From Nearest Side of Any Public Way or Nearest Building on Same Property (See Note)
275 or less	5	5
276 to 750	10	5
751 to 12,000	15	5
12,001 to 30,000	20	5
30,001 to 50,000	30	10
50,001 to 100,000	50	15
100,001 to 500,000	80	25
500,001 to 1,000,000	100	35
1,000,001 to 2,000,000	135	45
2,000,001 to 3,000,000	165	55
3,000,001 or more	175	60

   NOTE—No pump or tank shall be placed within the legal right-of-way limits of any State highway or any highway under the jurisdiction of DOT.

 (b)  Exposure of property. If end failure of horizontal tanks may expose property, the tank shall be placed with the longitudinal axis parallel to the more severe exposure.

 (c)  Common boundaries of diversely-owned property. If two tank locations of diverse ownership have a common boundary, the fire marshal may, with written consent of the owners of the two properties, substitute the distances set forth in §  13.2 (relating to spacing between aboveground tanks), for the minimum distances set forth in this section.

 (d)  Consideration for special conditions. These provisions may be altered in particular installations so as to be less restrictive or more restrictive at the discretion of the fire marshal after consideration of special features such as, but not restricted to, topographical conditions, nature of occupancy, proximity to buildings on adjoining property, height and character of construction of such buildings, capacity and construction of proposed tanks and character of liquids to be stored, degree of private fire protection to be provided, and facilities of the fire department to cope with flammable or combustible liquid fires.

 (e)  Application of this section. The provisions set forth in Tables 1—5 apply to distances between tanks and buildings on the property where installation is made.

 (f)  Protection for exposures. When such term is used in Tables 1—5, protection for exposures shall mean fire protection for structures on property adjacent to tanks. Structures located within the jurisdiction of any public fire department or within or adjacent to plants having private fire brigades shall be considered as having adequate protection for exposures.

 (g)  Requirements for fire prevention. If the required distance between tanks and buildings on the property where installation is made is greater than ten feet for tanks operated at pressures not in excess of 2 1/2 psig and used for storage of liquids other than those with boilover or unstable characteristics, such tanks may be closer to buildings than as set forth in Tables 1 and 5 but not less than 10 feet, if such buildings are of noncombustible construction, including resistive roof, with no openings on the side or sides facing the tanks. In the alternative, if openings would be present, wire glass in metal frame, fire shutters, or fire doors shall be acceptable on such openings.

 (h)  Skid tanks, similar portable equipment and drums are prohibited except when placed on farm and other isolated property for use in connection with farm equipment; or for private purposes only; or when use of such tanks or drums will be of purely temporary duration in connection with contract work such as road construction, strip mining and other transient operations where conventional type equipment would not be reasonably feasible or practicable; however, individual tanks shall not exceed 1,000 gallons capacity for storage of class I liquids, nor be in excess of 2,000 gallons capacity for storage of class II and class III liquids. Individual drums shall not exceed 60 gallons capacity. Individual tanks, similar portable equipment or drums shall not be interconnected and shall be kept closed when not in use.

   (1)  Skid tanks, similar portable equipment and drums must be located at least 40 feet from any building. Any vehicle, container or equipment being filled directly from a tank or drum must be at least 40 feet from any building. Pumps must be of an approved type and permanently attached. Dispensing devices used in connection with drums must be self-closing, of approved type and permanently attached. Dispensing devices requiring pressure on the tank or drum are prohibited.

   (2)  Skid tanks, similar portable equipment and drums shall be conspicuously marked in letters not less than 3 inches high with the name of the product which they contain and the words ‘‘INFLAMMABLE—KEEP 40 FEET FROM BUILDINGS.’’ This section does not pertain to drums stored under §  13.46 (relating to storage outside of buildings).

 (i)  Aboveground tanks shall not be located within 200 feet of any underground mine opening.

   The provisions of this §  13.1 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (63471) to (63473) and (5111) to (5114).

 (a)  The distance from shell to shell between flammable or combustible liquid storage tanks shall not be less than three feet.

 (b)  Except as provided in subsections (c) and (d), the distance from shell to shell between adjacent tanks shall not be less than 1/6 the sum of their diameters, except when the diameter of one tank is less than 1/2 the diameter of the adjacent tank, the distance between the two tanks shall not be less than 1/2 the diameter of the smaller tank.

 (c)  If a producing area for tanks storing crude petroleum has a capacity not in excess of 126,000 gallons (3,000 barrels), the distance between the tanks shall not be less than 3 feet; for tank capacities in excess of 126,000 gallons (3,000 barrels), the distance shall not be less than the diameter of the smaller tank.

 (d)  The distance between tanks storing unstable liquids shall not be less than 1/2 the sum of their diameters.

 (e)  If tanks are compacted in three or more rows, or in an irregular pattern, greater spacing or other means shall be provided at the discretion of the fire marshal so that inside tanks are accessible for fire fighting purposes.

 (f)  The minimum separation between a liquefied petroleum gas container and a flammable or combustible liquid storage tank shall be 20 feet. Suitable means shall be taken to prevent the accumulation of flammable or combustible liquids under adjacent liquefied petroleum gas containers, such as diking, diversion curbs, or grading. If flammable or combustible liquid storage tanks are diked, the liquefied petroleum gas containers shall be outside of the diked area wall. The foregoing provisions shall not apply when liquefied petroleum gas containers with capacities of 125 gallons or less are installed adjacent to fuel oil supply tanks with capacities of 660 gallons or less. Liquefied petroleum gas installations are under the jurisdiction of the Department of Labor and Industry.

   The provisions of this §  13.2 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5114) to (5115).

 Tanks shall be supported so as to prevent excessive concentration of loads on the supporting portion of the shell. Tank foundations shall be designed to minimize the possibility of uneven settling of the tank and to minimize corrosion in any part of the tank resting on the foundation. Tanks shall rest directly on the ground or on suitable foundations or supports of concrete, masonry, piling, or steel. Exposed steel supports shall be protected by fire resistive materials to provide a fire resistance rating of not less than 2 hours, with the exception of tanks with capacities of 660 gallons or less, installed on farm or other isolated property and only used for private purposes. No combustible piling shall be permitted above ground level.

   The provisions of this §  13.3 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5115) to (5116).

 If a tank is located in an area that may be subjected to flooding, installation shall be in accordance with § §  13.211—13.217 (relating to protection of tanks in flood areas).

 No structure, other than supports, shall be erected or placed beneath any aboveground tank, nor shall any combustible material, drum, or barrel be stored or kept under any such tank.

 (a)  General. The area surrounding a tank or a group of tanks shall be provided with drainage or shall be diked to prevent accidental discharge of liquid from endangering adjoining property or reaching waterways, except that in particular installations these provisions may be waived or altered at the discretion of the fire marshal when the tanks under consideration do not constitute a hazard to adjoining property.

 (b)  Drainage. If protection of adjoining property or waterways is by means of a natural or manmade drainage system, such systems shall comply with the following:

   (1)  A slope of not less than 1.0% away from the tank toward the drainage system shall be provided.

   (2)  The drainage system shall terminate in vacant land or in an impounding basin having a capacity not smaller than that of the largest tank served. This termination area and the route of the drainage system shall be located so that if the flammable or combustible liquids in the drainage system are ignited, the fire will not expose tanks or adjoining property.

   (3)  The drainage system, including automatic drainage pumps, shall not discharge to adjoining property, natural water courses, public sewers, or public drains, nor discharge in any manner that would constitute a hazard.

 (c)  Diked areas. If protection of adjoining property or waterways is accomplished by retaining the liquid around the tank by means of a diked area, such diked area shall comply with the following requirements:

   (1)  Except as set forth in paragraph (2), the diked area shall be designed to contain the volume of liquid that can be released from the largest tank.

   (2)  For tanks with fixed roofs containing crude petroleum with boilover characteristics, the diked area shall be designed to contain the volume of liquid that can be released from all tanks served by the enclosure.

   (3)  Walls of a diked area shall be of earth, steel, concrete, or solid masonry designed to be liquid tight and to withstand a full hydrostatic head. Earthen walls 3 feet or more in height shall have a flat section at the top not less than 2 feet wide. The slope of an earthen wall shall be consistent with the angle of repose of the material of which the wall is constructed. Dike walls shall be restricted to a maximum height of 6 feet above interior grade. The use of building walls as part of dike walls is prohibited.

   (4)  Provision shall be made for draining water from diked areas. Drainage shall have a uniform slope of not less than 1.0% away from tanks toward a sump, drainbox, or other safe means of disposal located at the greatest practicable distance from the tank, and shall be accessible to control under fire conditions. Such drains shall be kept closed except when in use and shall be designed so that they do not permit flammable or combustible liquids to enter natural water courses, sewers, or drains if their presence would constitute a hazard. Pumps or other means used in providing drainage from diked areas shall be manually controlled only.

   (5)  No loose combustible material, drum, or barrel shall be permitted within the diked area.

   (6)  In densely populated areas a fence which will enclose the tank or equipment may be required where public access to the tank is not otherwise restricted.

 (d)  Particular installations. These provisions may be altered in particular installations at the discretion of the fire marshal after consideration of special features such as topographical conditions, nature of occupancy and proximity to buildings, height and character of construction of such buildings, capacity and construction of proposed tanks and character of liquids to be stored, degree of private fire protection to be provided, and facilities of fire departments to cope with flammable or combustible liquid fires.

   The provisions of this §  13.6 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5116) to (5118).

 (a)  General. Tanks shall be designed and constructed to safely withstand the service to which they are subjected. Use of a tank vehicle or railroad tank car, not meeting the requirements of this section, for purposes other than its designed use such as a storage or supply tank, is prohibited.

 (b)  Materials and fabrication. The materials and fabrication of tanks shall conform to the following:

   (1)  Tanks shall be built of steel unless the character of liquids stored requires some other material. Tanks built of materials other than steel shall be designed to specifications embodying principles recognized as good engineering design for the material used. Unlined concrete tanks may be used for storing flammable or combustible liquids having a gravity of 40°API or heavier. Concrete tanks with special lining may be used for other services if the design is in accordance with sound engineering practice. Tanks may have combustible or noncombustible linings. Special engineering considerations are required if the specific gravity of the liquid to be stored exceeds that of water or if the tanks are designed to contain flammable or combustible liquids at a liquid temperature below 0°F.

   (2)  Tanks may be of any shape or type consistent with sound engineering design. Metal tanks shall be welded, riveted and caulked, brazed, or bolted, or constructed by use of a combination of these methods. Filler metal used in brazing shall be nonferrous metal or an alloy having a melting point above 1000°F. and below that of the metal joined.

 (c)  Atmospheric tanks. The following contain the minimum requirements for construction of steel atmospheric tanks:

   (1)  Underwriters’ Laboratories, Incorporated, Subject No. 142—1981, Standard for Steel Aboveground Tanks for Flammable and Combustible Liquids.

   (2)  American Petroleum Institute Standard No. 650—1980, Welded Steel Tanks for Oil Storage.

   (3)  American Petroleum Institute Standards No. 12B—1977, Specification for Bolted Tanks for Storage of Production Liquids; No. 12MD—1982, Specification for Field Welded Tanks for Storage of Production Liquids; or No. 12F—1982, Specification for Shop Welded Tanks for Storage of Production Liquids. Tanks built in accordance with these standards shall be used only as production tanks for storage of crude petroleum in oil producing areas.

   (4)  Skid tanks and similar portable equipment of 61 to 660 gallons capacity shall be of single compartment design and constructed in accordance with accepted engineering practice. Joints shall be welded.

     (i)   Tank heads over 6 feet in diameter shall be dished, stayed, braced or reinforced.

     (ii)   Minimum thickness shall be in accordance with the following:

     (iii)   A fill opening shall be provided and shall be equipped with a closure design, so that it may be locked. The fill opening shall be separate from the vent opening.

     (iv)   Tanks not mounted on runners or resting on metal legs shall be mounted in a stable position on noncombustible blocks approximately 6 inches in height, so as to protect the bottom of the tank from corrosion.

   (5)  Skid tanks and similar portable equipment of 661 to 2,000 gallons capacity shall be constructed in accordance with the standards contained in the publications referenced in subsection 5(c)(1) and (2).

 (d)  Low pressure tanks. The following contain the minimum requirements for construction of steel low pressure tanks:

   (1)  American Petroleum Institute Standard No. 620—1982, Recommended Rules for the Design and Construction of Large, Welded Low-Pressure Storage Tanks.

   (2)  The normal operating pressure of the tank shall not exceed the design pressure of the tank.

   (3)  Atmospheric tanks built according to Underwriters’ Laboratories, Incorporated, Subject No. 142—1981 may be used for operating pressures not exceeding one psig and shall be limited to 2½ psig under emergency venting conditions.

   The provisions of this §  13.7 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5118) to (5119).

 (a)  Normal venting. The normal venting requirements for construction and use of tanks shall conform to the following:

   (1)  Atmospheric tanks shall be adequately vented to prevent, as a result of filling or emptying and atmospheric temperature changes, development of pressure or vacuum sufficient to distort the roof of a cone roof tank or pressure exceeding the design pressure in the case of other atmospheric tanks.

   (2)  Low pressure tanks shall be adequately vented to prevent development of pressure or vacuum, as a result of filling or emptying and atmospheric temperature changes, from exceeding the design pressure of the tank. Protection shall also be provided to prevent overpressure from any pump discharging into the tank where the pump discharge pressure may exceed the design pressure of the tank.

   (3)  If a tank has more than one fill or withdrawal connection and simultaneous filling or withdrawal can be made, the vent size shall be based on the maximum anticipated simultaneous flow.

   (4)  Unless the vent is designed to limit the internal pressure to 2 1/2 psig or less, the outlet of vents and vent drains shall be arranged to discharge in such a manner as to prevent localized overheating of any part of the tank in the event vapors from such vents are ignited.

   (5)  Tanks storing class IA liquids shall be equipped with venting devices which shall be normally closed except when venting under pressure or vacuum conditions. Tanks storing class IB and class IC liquids shall be equipped with venting devices which shall be normally closed except when venting under pressure or vacuum conditions, or with approved flame arresters. This paragraph shall not apply to tanks with capacities of 3,000 barrels or less containing crude petroleum in crude producing areas and outside aboveground atmospheric tanks with capacities under 1,000 gallons containing other than class IA liquids which may have open vents.

   (6)  Flame arresters or venting devices required in paragraph (5) may be omitted for class IB and class IC liquids if conditions are such that their use may, in case of obstruction, result in tank damage. Liquid properties justifying the omission of such devices include, but are not limited to, condensation, corrosiveness, crystallization, polymerization, freezing, or plugging. When any of these conditions exist, consideration may be given to heating, use of devices employing special materials of construction, the use of liquid seals, or inerting; for further information, see Standard No. 69—1978, Explosion Prevention Systems.

   (7)  Normal vents shall be sized in accordance with either the American Petroleum Institute, Standard No. 2000—1982, Venting Atmospheric and Low-Pressure Storage Tanks, or other accepted standard, or shall be at least as large as the filling or withdrawal connection, whichever is larger, but shall not in any case be less than the requirements set forth in the following table:

   (8)  Skid tanks and similar portable equipment shall be provided with a free opening vent of the following nominal pipe size, to relieve vacuum or pressure which may develop in normal operation or from fire exposure:

     (i)   Vents shall be arranged to discharge in such a way as to prevent localized or overheating of, or flame impingement on, any part of the tank in the event vapors from such vents are ignited.

     (ii)   Drums equipped with dispensing devices must be provided with pressure and vacuum relief vents with flame arresters. These vents are to be in addition to any vent which may be an integral part of the dispensing device being used in connection with the drum.

   (9)  For tanks in excess of 1,100 gallons capacity, emergency relief venting for fire exposure shall be as provided under subsection (b).

 (b)  Emergency relief venting for fire exposure. Every aboveground storage tank shall have some form of construction or device that will relieve excessive internal pressure caused by exposure fires, and such construction or device shall conform to the following:

   (1)  In a vertical tank, the construction may take the form of a floating roof, lifter roof, a weak roof-to-shell seam, or other approved pressure relieving construction. The weak roof-to-shell seam shall be constructed to fail preferential to any other seam. Where entire dependence for such additional relief is placed upon some device other than a weak roof seam or joint, the total venting capacity of both normal and emergency vents shall be enough to prevent rupture of the shell or bottom of the tank if vertical, or of the shell or heads if horizontal. Such device may be a self-closing manhole cover, or one using long bolts that permit the cover to lift under internal pressure.

   (2)  If emergency venting is not provided in accordance with paragraph (1), the total capacity of both normal and emergency venting devices shall be not less than that derived from the following table, except as provided in paragraphs (4) and (5):

Wetted Area Versus Cubic Feet Free Air per Hour
at 14.7 p.s.i.a. and 60°F.

Square Feet	CFH	Square Feet	CFH	Square Feet	CFH
20	21,100	160	168,000	900	493,000
30	31,600	180	190,000	1,000	524,000
40	42,100	200	211,000	1,200	557,000
50	52,700	250	239,000	1,400	587,000
60	63,200	300	265,000	1,600	614,000
70	73,700	350	288,000	1,800	639,000
80	84,200	400	312,000	2,000	662,000
90	94,800	500	354,000	2,400	704,000
100	105,000	600	392,000	2,800	742,000
120	126,000	700	428,000	and over
140	147,000	800	462,000

   (3)  The wetted area of the tank, when such term is used in paragraph (2), shall be calculated on the basis of 55% of the total exposed area of a sphere or spheroid, 75% of the total exposed area of a horizontal tank, and the first 30 feet abovegrade of the exposed shell area of a vertical tank. Approximate wetted areas for horizontal tanks may be found in the following table:

   (4)  The total emergency relief venting capacity for any specific liquid may be determined by the following formula:

       Cubic feet of free air per hour =

       V = cubic feet of free air per hour from the table of paragraph (2).

       L = latent heat of vaporization of specific liquid in Btu per pound.

       M = molecular weight of specific liquid.

   (5)  The required air flow rate, as set forth in paragraphs (2) and (3), may be multiplied by the following appropriate factor set forth when protection is provided as indicated; only one factor may be used for any one tank:

     (i)   Factor .5 for drainage in accordance with the drainage provisions of §  13.6 (relating to dikes, walls and drainage) for tanks over 200 square feet of wetted area.

     (ii)   Factor .3 for approved water spray.

     (iii)   Factor .3 for approved insulation.

     (iv)   Factor .15 for approved water spray with approved insulation.

   (6)  Venting devices shall be certified by the manufacturer as to actual rated flow capacity in cubic feet of free air per hour, specifying the pressure in psig at which the flow capacity was determined. The stamping of such information on the devices by the manufacturer shall be acceptable as certification for this purpose.

   (7)  The outlet of all vents and vent drains on tanks equipped with emergency venting to permit pressures exceeding 2½ psig shall be arranged to discharge in such a way as to prevent localized overheating of any part of the tank in the event vapors from such vents are ignited.

 (c)  Vent piping for aboveground tanks. Vent piping for aboveground tanks shall conform to the following:

   (1)  Vent piping shall be constructed under § §  13.51—13.58 (relating to piping, valves and fittings). Where vent piping for tanks storing class I liquids is adjacent to buildings or public ways, the vent piping shall be located so that the vapors are released at a safe point away from buildings and not less than 12 feet above the adjacent ground level. In order to aid their dispersion, vapors shall be discharged upward so that flammable vapors will not be trapped by eaves or other obstructions and shall be at least 5 feet from building openings. Vent outlets for all classes of flammable and combustible liquids shall be above normal snow accumulation on top of tanks.

   (2)  When tank vent piping is manifolded, pipe sizes shall be able to discharge, within the pressure limitations of the system, the vapors they may be required to handle when manifolded tanks are subject to the same fire exposure. The manifolding of tank vent piping shall be avoided except if required for special purposes such as vapor recovery, vapor conservation or air pollution control.

   (3)  Vent piping for tanks storing class I liquids shall not be manifolded with vent piping for tanks storing class II or class III liquids unless positive means are provided to prevent the vapors from class I liquids from entering tanks storing class II or class III liquids to prevent contamination and possible change in classification of the less volatile liquid.

   The provisions of this §  13.8 issued under act of April 27, 1927 (P. L. 450, No. 291) (35 P. S. § §  1181—1194).

   The provisions of this §  13.8 amended through June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5119) to (5122), (63474) to (63475), and (63948).

 Each connection to an aboveground tank storing flammable or combustible liquids, located below normal liquid level, shall be provided with an internal or external control valve located as close as practicable to the shell of the tank. Except for flammable or combustible liquids whose chemical characteristics are incompatible with steel, such valves, when external, and their connections to the tank shall be of steel. When materials other than steel are necessary, they shall be suitable for the pressures, structural stresses and temperatures involved, including fire exposures.

 Each tank or system shall be electrically grounded in an approved manner.

 All tanks shall be tested for strength and tightness before they are placed in service in accordance with the applicable code or standard under which they were built. This test shall be made at operating pressure with air, inert gas or water prior to placing the tank in service.

 Tanks receiving transfer of flammable or combustible liquid from mainline pipelines or marine vessels shall be:

 (1)  Gauged at frequent intervals while receiving transfer of product, and communications maintained with mainline pipeline or marine personnel so that flow can be promptly shut down or diverted;

 (2)  Equipped with an independent high level alarm located where personnel are on duty during the transfer and can promptly arrange for flow stoppage or diversion; or

 (3)  Equipped with an independent high level alarm system that will automatically shut down or divert flow.

   The provisions of this §  13.12 adopted June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131.

UNDERGROUND STORAGE

§ 13.21. Location.

 A flammable or combustible liquid storage tank may be located outside underground, if such installation meets § §  13.21—13.26 (relating to underground storage). The tank shall be so located with respect to existing building foundations and supports that the loads carried by the supports are not transmitted to the tank. The distances from any part of a tank storing class I liquids to the nearest wall of any basement, pit or cellar shall be not less than 1 foot, and from the line of any adjoining property not less than 3 feet. The distance from any part of a tank storing class II or class III liquids to the nearest wall of any basement, pit or cellar, and from the line of any adjoining property shall be not less than 1 foot. When tank excavations are lower than wall or column footings, the edge of the ditch shall be outside a slope of one horizontal to one vertical from the edge of such footing. No tank shall be placed within the legal right-of-way limits of any highway, or any highway under the jurisdiction of DOT, nor within 200 feet of an underground mine opening.

   The provisions of this §  13.21 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5125) to (5126).

 Excavation for underground storage tanks shall be made with due care to avoid undermining of foundations of existing structures. Underground tanks shall be set on a firm foundation, at least 2 feet apart, and surrounded with noncorrosive, uniform, inert materials such as soft earth or sand well tamped in place. Tanks shall be covered with a minimum of 2 feet of earth, or shall be covered with not less than 1 foot of earth on top of which shall be placed a slab of reinforced concrete not less than 4 inches thick. When underground tanks are or are likely to be subjected to traffic, they shall be protected against damage from vehicles passing over them by at least 3 feet of earth cover, or 18 inches of well tamped earth, plus 6 inches of reinforced concrete or 8 inches of asphaltic concrete. When asphaltic or reinforced concrete paving is used as part of the protection it shall extend at least 1 foot horizontally beyond the outline of the tank in all directions.

 If a tank is located in an area that may be subjected to flooding, installation shall be in accordance with § §  13.211—13.217 (relating to protection of tanks in flood areas).

 (a)  General. Underground tanks shall be designed and constructed to safely withstand the service to which they are subjected. Tanks shall not contain petroleum products containing mixtures of a non-petroleum nature without evidence of compatibility. This shall include ethanol or methanol blends.

 (b)  Materials. Tanks shall be built of steel except as provided in this subsection. Tanks may be built of materials other than steel for installation underground or if required by the properties of the liquid stored. Tanks built of materials other than steel shall be designed to specifications embodying principles recognized as good engineering design for the material used. Unlined concrete tanks may be used for storing flammable or combustible liquids having a gravity of 40 API or heavier. Concrete tanks with special lining may be used for other services if the design is in accordance with sound engineering practice. Tanks may have combustible or noncombustible linings. Special engineering consideration is required if the specific gravity of the liquid to be stored exceeds that of water or if the tanks are designed to contain flammable or combustible liquids at a liquid temperature below 0°F.

 (c)  Fabrication. Underground tank construction shall be in accordance with the following publications:

   (1)  Underwriters’ Laboratories, Incorporated, Standard No. 58—1976, Specifications for Underground Tanks for Flammable and Combustible Liquids, sets forth the minimum requirements for construction of steel underground tanks.

   (2)  Underwriters’ Laboratories, Incorporated, Standard No. 1316—83T, Specifications for Glass-Fiber Reinforced Plastic Underground Storage Tanks for Petroleum Products, sets forth the minimum requirements for construction of nonmetallic underground tanks.

 (d)  Protection against corrosion. Tanks shall be protected by:

   (1)  Use of protective coatings or wrappings;

   (2)  Cathodic protection; or

   (3)  Corrosion resistant materials of construction such as special alloys, fiber glass reinforced plastic or fiber glass reinforced plastic coatings, or equivalent approved systems.

   The provisions of this §  13.24 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (63476).

 (a)  Connections for all tank openings shall be liquid tight.

 (b)  Openings for manual gaging, if independent of the fill pipe, shall be provided with a liquid-tight cap or cover. Covers shall be kept closed when not gaging. If inside a building, each such opening shall be protected against liquid overflow and possible vapor release by means of a spring loaded check valve or other approved device.

 (c)  Fill and discharge lines shall enter tanks only through the top. Fill lines shall be sloped toward the tank.

 (d)  For class IB and class IC liquids other than crude oils, gasolines, and asphalts, the fill pipe shall be so designed and installed as to minimize the possibility of generating static electricity by terminating within six inches of the bottom of the tank.

 (e)  Filling and emptying and vapor recovery connections for class I, class II, or class III liquids which are made and broken shall be located outside of buildings at a location free from any source of ignition and not less than five feet away from any building opening. Such connections shall be closed and liquid-tight when not in use and shall be properly identified.

 (f)  Tank openings provided for purposes of vapor recovery shall be protected against possible vapor release by means of a spring-loaded check valve or dry-break connection or other approved device unless the opening is pipe-connected to a vapor processing system. Openings designed for combined fill and vapor recovery shall also be protected against vapor release unless connection of the liquid delivery line to the fill pipe simultaneously connects the vapor recovery line. All connections shall be vapor-tight.

 (a)  Vent pipes from underground storage tanks storing class I liquids shall be so located that the discharge point is outside of buildings, higher than the fill-pipe opening, and not less than 12 feet above the adjacent ground level. Vent pipes shall discharge only upward in order to disperse vapors. Vent pipes shall not be obstructed by devices provided for vapor recovery or other purposes unless the tank and associated piping and equipment are otherwise protected to limit back-pressure development to less than the maximum working pressure of the tank and equipment by the provision of pressure-vacuum vents, rupture discs, or other tank-venting devices installed in the tank-vent lines. Vent outlets and devices shall be protected to minimize the possibility of blockage from weather, dirt, or insect nests and shall be so located and directed that flammable vapors will not accumulate or travel to an unsafe location, enter building openings, or be trapped under eaves. Tanks containing class IA liquids shall be equipped with pressure and vacuum venting devices which shall be normally closed except when venting under pressure or vacuum conditions. Tanks storing class IB or class IC liquids shall be equipped with pressure-vacuum vents or with listed flame arresters. Tanks storing gasoline are exempt from the requirements for pressure and vacuum venting devices, except as required to prevent excessive back pressure, or flame arresters, provided the vent does not exceed 3 inches nominal inside diameter.

 (b)  Vent pipes from tanks storing class II or class III liquids shall terminate outside of building and higher than the fill-pipe opening. Vent outlets shall be above normal snow level. They may be fitted with return bends, coarse screens, or other devices to minimize ingress of foreign material. Vent piping shall be constructed in accordance with §  13.51 (relating to scope and application).

 (c)  Tank-venting systems shall be provided with sufficient capacity to prevent blowback of vapor or liquid at the fill opening while the tank is being filled. Vent pipes shall not be less than 1¼ inch nominal inside diameter. The required venting capacity depends upon the filling or withdrawal rate, whichever is greater, and the vent-line length. Unrestricted vent piping sized in accordance with the following table will prevent back-pressure development in tanks from exceeding 2.5 psig Where tank venting devices are installed in vent lines, their flow capacities shall be determined in accordance with §  13.8(b)(6) (relating to vents).

 (d)  Vent pipes shall be so laid as to drain toward the tank without sags or traps in which liquid can collect. They shall be located so that they will not be subjected to physical damage. The tank end of a vent pipe shall enter the tank through the top.

 (e)  When tank vent piping is manifolded, pipe sizes shall be such as to discharge, within the pressure limitations of the system, the vapors they can be required to handle when manifolded tanks are filled simultaneously; except that, for service stations, the capacity of manifolded vent piping shall be sufficient to discharge vapors generated when two manifolded tanks are simultaneously filled.

 (f)  Vent piping for tanks storing class I liquids shall not be manifolded with vent piping for tanks storing class II or class III liquids, unless positive means are provided to prevent the vapors from class I liquids from entering tanks storing class II or class III liquids, to prevent contamination and possible change in classification of the less volatile liquid.

 (g)  Where tanks are filled by the use of a pump through tight connections, a vent pipe not less in size than the discharge of the pump shall be used. Under no circumstances shall the vent pipe diameter be less than 1¼ inches nominal inside diameter.

 (h)  The design and location of vent pipe systems (except those designed for areas of mandatory vapor recovery) shall take into consideration the proximity of neighboring buildings with respect to flammable and noxious vapors.

   The provisions of this §  13.25 amended through June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (63477) to (63480).

 (a)  Before being covered or placed in use, tanks and the piping connected thereto shall be tested for tightness. Tanks shall be tested hydrostatically, by air pressure, or by other methods approved by the fire marshal, at not less than 3 psig nor more than 5 psig When the vertical length of the fill and vent pipes is such that when filled with liquid the static head imposed upon the bottom of the tank exceeds 10 psig, the tank and related piping shall be tested hydrostatically to a pressure equal to the static head thus imposed. This test shall be maintained for at least 30 minutes with no drop in pressure or for a sufficient time to complete visual inspection of all joints and connections.

 (b)  When seepage or vapors in the vicinity of an underground tank, or an accumulation of water in the tank, or if the proximity of the tank to an area of unconfined flammable or combustible liquids or vapors indicate a tank as an obvious or likely source, or where unexplainable losses exceed ¾ of 1.0% of the average monthly receipts, the fire marshal shall be notified and he may require the immediate testing of the tanks. Such testing shall be by approved methods of ‘‘standpipe’’ testing or an approved testing device capable of detecting leaks as small as .05 gallons in one hour, adjusted for variables. Costs attendant to such tests shall be the responsibility of the owners of the tanks. Test records shall be kept for a period of at least 1 year.

 (c)  In those cases where daily inventory records indicate unexplainable losses exceeding ¾ of 1.0% of the average monthly receipts, the following steps shall be taken in an expeditious manner prior to tank testing.

   (1)  The inventory record shall be rechecked for error.

   (2)  If no error is apparent, an independent calculation of apparent loss shall be made starting from a point in time where the records indicate a no loss condition.

   (3)  If paragraph (2) confirms an apparent loss, the readily accessible physical facilities on the premises shall be carefully inspected for evidence of leakage.

   (4)  If paragraph (3) does not disclose a leak, the dispensing devices used for the particular product involved in the apparent loss shall be checked for calibration.

   (5)  If paragraph (4) does not explain the loss, and if the piping system can be tested without the need for excavation, the piping system between the storage tank and dispensers shall be tested under §  13.58 (relating to testing).

 If it is necessary to excavate to perform a piping test, such a test shall be conducted after a storage tank test has been performed under subsection (b).

   (6)  If paragraph (5) does not disclose a leak, the storage tanks shall be tested for tightness under subsection (b).

   (7)  If any of the tests in paragraphs (1) to (6) or investigations indicate the source of the loss, the owner shall take immediate action to correct the system failure.

 (d)  If paragraphs (1)—(7) do not confirm the apparent loss, the daily inventory shall be continued with a daily independent verification. Additional surveillance of the facility should be engaged to insure against unauthorized removal of the product.

 (e)  Air pressure tests of tanks or piping containing flammable or combustible liquids are prohibited.

   The provisions of this §  13.26 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (63480).

 An underground tank found to be leaking shall be removed or abandoned in place under §  13.222 (relating to underground tanks); or may be repaired in a manner specifically approved by the fire marshal.

   The provisions of this §  13.27 adopted June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131.

   This section cited in 37 Pa. Code §  13.221 (relating to tanks temporarily out of service).

INSIDE BUILDING STORAGE

§ 13.31. Scope.

 The provisions of § §  13.31—13.38 (relating to inside building storage) apply to unenclosed tanks and tanks enclosed in unfilled vaults within buildings. When tanks are placed in filled enclosures, they shall meet the provisions of this chapter for underground tanks.

 Tanks for storage of class I liquids shall not be installed inside buildings except as set forth in §  13.141 and §  13.151 (relating to commercial and industrial establishments and processing plants).

   The provisions of this §  13.32 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (63481).

 (a)  An unenclosed supply tank larger than 10 gallons shall be placed not less than 5 feet horizontally from any fire or flame either in or external to the appliance being served by the tank.

 (b)  A supply tank located above the lowest story, cellar or basement shall not exceed 60 gallons capacity, and the total capacity of tanks so located shall not exceed 60 gallons.

 (c)  Except as set forth in subsection (d), a supply tank shall not be larger than 660 gallons. Not more than one 660 gallon tank or two tanks of aggregate capacity of 660 gallons or less shall be connected to one oil-burning appliance, and the aggregate capacity of such tanks installed in the lowest cellar or basement of a building shall not exceed 1,320 gallons. Such tanks may be installed outside aboveground adjacent to buildings, provided the distance to the line of adjoining property is not less than that required by §  13.1 (relating to relative location to property) and tanks shall be suitably protected from physi- cal damage incident to outside use. Outside supply tanks may be equipped with an approved manually operated dispensing device that takes suction through the top of the tank for the purposes of dispensing fuel for use in supplemental heating devices which use identical fuels as that stored in the supply tank. Domestic use of beneath building tanks or of inside storage tanks or containers (including drums) that exceed the requirements of §  13.44 (relating to manner and limitation of storage) is prohibited.

 (d)  Tanks exceeding 660 gallons individual capacity or 1,320 gallons aggregate capacity in an individual building or in a section of a building separated by fire walls shall be installed in an enclosure constructed in a manner approved by the fire marshal.

   The provisions of this §  13.33 amended through October 5, 1984, effective October 6, 1984, 14 Pa.B. 3624. Immediately preceding text appears at serial pages (90106) to (90107).

 (a)  The outlet of a vapor recovery line for which connections are made and broken shall be located outside of buildings at a location free from any source of ignition and not less than 5 feet away from any building opening. Such connections shall be closed and tight when not in use and shall be properly identified.

 (b)  Tank openings provided for purposes of vapor recovery shall be protected against possible vapor release by means of a spring-loaded check valve or drybreak connections, or other approved device, unless the opening is pipe-connected to a vapor processing system. Openings designed for combined fill and vapor recovery shall also be protected against vapor release unless connection of the liquid delivery line to the fill pipe simultaneously connects the vapor recovery line. All connections shall be vapor-tight.

 (a)  A fill pipe shall terminate outside of a building at a point at least 2 feet from any building opening at the same or lower level. A fill pipe shall terminate in a manner designed to minimize spilling when the filling hose is disconnected. Fill opening shall be equipped with a tight metal cover designed to discourage tampering. Where a supply or storage tank has been removed from within a building, it shall be the responsibility of the owner of the tank to insure that the portion of the fill pipe system terminating outside the building is also removed at the same time to preclude the accidental use of the fill pipe which is no longer connected to the tank.

 (b)  A return line from a burner or pump to a supply tank shall enter the top of the tank.

 (c)  Cross connections, except between two supply tanks not exceeding 660 gallon aggregate capacity, permitting gravity flow from one tank to another shall be prohibited.

 (d)  An auxiliary tank shall be filled by a pump transferring the oil through continuous piping from the supply tank.

 (e)  An auxiliary tank shall be located at a level above the top of the supply tank from which it is filled.

 (f)  An auxiliary tank shall be provided with an overflow pipe draining to the supply tank and extending into the top of the supply tank not more than one inch. This requirement shall not apply to an auxiliary tank specifically listed for use without an overflow pipe.

 (g)  An overflow pipe from an auxiliary tank and a return line from a burner or pump shall have no valves or obstructions.

 Tanks shall have vent openings and vent pipes of sufficient size to prevent abnormal pressure in the tank during filling. Vent pipes shall terminate outside of buildings, higher than the fill pipe opening, and above normal snow accumulation. All domestic fuel tank installations shall be equipped with a signal alarm to prevent overflow. Where tanks are filled by the use of a pump through tight connection, a vent pipe not less in size than the discharge of the pump shall be used. Under no circumstances shall the vent pipe diameter be less than 1¼ inches nominal inside diameter.

   The provisions of this §  13.34 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (63484).

 (a)  General. Tanks shall be designed and constructed to safely withstand the service to which subjected.

 (b)  Materials. Tanks shall be built of steel unless the character of liquids stored requires other material. Tanks built of materials other than steel shall be designed to specifications embodying principles recognized as good engineering design for the material used. Unlined concrete tanks may be used for storing flammable or combustible liquids having a gravity of 40 API or heavier. Concrete tanks with special lining may be used for other services if the design is in accordance with sound enginering practice. Tanks may have combustible or noncombustible linings. Special engineering consideration is required if the specific gravity of the liquid to be stored exceeds that of water or if the tanks are designed to contain flammable or combustible liquids at a liquid temperature below 0°F.

 (c)  Fabrication. Fabrication of tanks shall conform to the following:

   (1)  Tanks may be of any shape or type consistent with sound engineering design. Metal tanks shall be welded, riveted and caulked, brazed or constructed by use of a combination of these methods. Filler metal used in brazing shall be nonferrous metal or an alloy having a melting point above 1000°F. and below that of the metal joined.

   (2)  The following shall be the minimum requirements for construction of steel inside tanks:

     (i)   Underwriters’ Laboratories, Incorporated, Standard No. 80—1974, Specifications for Steel Inside Tanks for Oil Burner Fuel, shall apply to tanks of 660 gallons capacity or less.

     (ii)   Enclosed tanks of greater capacity than 660 gallons shall meet applicable design and construction requirements of this chapter for underground tanks if horizontal, and for aboveground tanks if vertical.

   (3)  If the vertical length of the fill and vent pipes is such that when filled with liquid the static head imposed upon the bottom of the tank exceeds ten psig the tank shall be designed for the maximum static head which will be imposed.

   The provisions of this §  13.35 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (63484) to (63485), and (5133).

 Inside storage and supply tanks shall be securely supported by rigid, noncombustible supports to prevent settling, sliding, or lifting.

   The provisions of this §  13.36 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (5133).

 If a supply tank larger than 10 gallons is provided with an opening in the bottom for use as a burner supply connection or as a drain, the tank shall be pitched toward the opening with a slope of not less than 1/4 inch per foot of length.

   The provisions of this §  13.37 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5133) to (5134).

 (a)  All tanks shall be tested for strength and tightness before they are placed in service in accordance with the applicable code or standard under which they were built. This test shall be made at operating pressure with air, inert gas, or water prior to placing the tank in service.

 (b)  When the vertical length of the fill and vent pipes is such that when filled with liquid the static head imposed upon the bottom of the tank exceeds ten psig the tank and related piping shall be tested hydrostatically to a pressure equal to the static head thus imposed.

   This section cited in 37 Pa. Code §  13.31 (relating to scope); and 37 Pa. Code §  13.161 (relating to general provisions).

CLOSED CONTAINERS

§ 13.41. Scope.

 The provisions set forth in § §  13.41—13.46 (relating to closed containers) apply to the storage of flammable or combustible liquids in drums or other portable closed containers not exceeding 60 gallons individual capacity inside buildings, or outside of buildings in areas used solely for such storage, but are not applicable to storage in bulk plants, service stations, commercial and industrial establishments, processing plants, heating and power devices and distilleries.

   The provisions of this §  13.41 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (5134).

 Inside storage rooms shall comply with the requirements of the Fire and Panic Act, except in cities of the Second Class A. In cities of the Second Class A, design and construction of inside storage rooms shall be in a manner approved by the fire marshal.

   The provisions of this §  13.42 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (5135).

 Outside storage cabinets shall be constructed and utilized in an approved manner.

   The provisions of this §  13.43 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5135) to (5136).

 (a)  Flammable or combustible liquids, including stock for sale, shall not be stored near exits, stairways, or corridors leading to the exits or stairways.

 (b)  The storage of flammable or combustible liquids in closed containers shall comply with the following occupancy provisions, except that the fire marshal may impose a quantity limitation or require greater protection if he determines that an unusual hazard to life or property is involved, or he may authorize an increase of the given amounts if the type construction, fire protection provided, or other factors substantially reduce the hazard:

   (1)  Dwellings and residential buildings containing not more than two dwelling units and attached and detached garages. Storage in excess of 5 gallons of class I liquid is prohibited. Storage in excess of 20 gallons of class II or class III liquids combined is prohibited. Flammable or combustible liquids shall be stored in closed metal containers, safety cans, or approved nonmetallic containers. No individual container shall exceed 5 gallons capacity. Flam- mable and combustible liquids shall not be transferred or dispensed from containers to fuel tanks, reservoir tanks, or other containers inside of buildings. This section does not pertain to supply tanks connected by piping to oil burners or power devices. See §  13.161 (relating to general provisions).

   (2)  [Reserved].

   (3)  Hospitals, nursing homes and related health care facilities. Inside storage, handling, use and fire control of flammable or combustible liquids throughout this Commonwealth shall be in accordance with 28 Pa. Code (relating to health and safety).

   The provisions of this §  13.44 amended through October 5, 1984, effective October 6, 1984, 14 Pa.B. 3624. Immediately preceding text appears at serial pages (90113) to (90114).

 (a)  Suitable fire extinguishers are recommended wherever flammable or combustible liquids are stored or used inside buildings described in §  13.44(b)(1) (relating to manner and limitations of storage).

 (b)  [Reserved]

 (c)  Open flames, smoking and other sources of ignition are not permitted in flammable or combustible liquid storage rooms.

 (d)  Materials which may react with water to produce flammable vapors may not be stored in the same room with flammable or combustible liquids.

 (e)  Use of class I liquids as degreasing or cleaning agents are prohibited.

   The provisions of this §  13.45 amended June 22, 1984, effective June 23, 1984, 14 Pa.B. 2131; corrected October 21, 1988, effective June 23, 1984, 18 Pa.B. 4789. Immediately preceding text appears at serial page (90114).

 (a)  Allowable construction. Drums constructed in accordance with DOT specifications may be stored out of doors in areas used solely for such storage. Drums equipped with dispensing devices shall be equipped with pressure and vacuum relief in order to prevent drum rupture under fire conditions.

 (b)  Basic safeguards. Basic safeguards for outdoor storage shall conform to the following:

   (1)  Drums may not be stored outside on building platforms or between buildings, or in a location adjacent thereto, in such a manner that they would contribute to the spread of fire.

   (2)  Storage of class I liquids shall be limited to groups of 100 drums or less located at least 60 feet from the nearest building or line of adjoining property that may be built upon and each group shall be separated by at least 40 feet. Storage of class II or class III liquids shall be limited to groups of 300 drums or less located at least 50 feet from the nearest building or line of adjoining property that may be built upon and each group shall be separated by at least 30 feet. These distances may be reduced 50% if sprinklers and drainage away from exposures are provided. In particular installations, the distance requirements to buildings may be altered at the discretion of the fire marshal after consideration of the height, size and character of construction, and occupancy of the exposed buildings. The height of piles shall be consistent with stability and strength of containers. No container may be more than 200 feet from a 12 foot wide access way to permit approach of fire control apparatus.

   (3)  Drum storage shall be located to prevent runoff, or drainage toward other storage or buildings. The area shall be kept clear of grass, weeds and other foreign combustibles. Signs shall be posted prohibiting open flames and smoking.

   (4)  Drum storage for private purposes shall be in accordance with §  13.1(h) (relating to relative location to property).

   (5)  At least one properly maintained 20BC fire extinguisher shall be available at all times at areas of outside container storage.

   The provisions of this §  13.46 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (63486) to (63487).

   This section cited in 37 Pa. Code §  13.1 (relating to relative location to property); 37 Pa. Code §  13.41 (relating to scope); 37 Pa. Code §  13.101 (relating to storage); 37 Pa. Code §  13.141 (relating to scope and application); and 37 Pa. Code §  13.151 (relating to scope and application).

PIPING, VALVES AND FITTINGS

§ 13.51. Scope and application.

 (a)  Sections 13.51—13.58 (relating to piping, valves and fittings) do not apply to tubing or casing on oil wells and piping connected directly thereto, floating craft or aircraft, or piping within the scope of an applicable boiler and pressure vessel code.

 (b)  Piping systems consist of pipe, flanges, bolting, gaskets, valves, fittings, the pressure containing parts of other components such as expansion joints and strainers, and devices which serve such purposes as mixing, separating, snubbing, distributing, metering or controlling flow.

 (a)  The design, including selection of materials, fabrication, assembly and the test and inspection of piping systems containing flammable or combustible liquids shall be suitable for the expected working pressures and structural stresses. Conformity with the applicable provisions of the American National Standard Code for Pressure Piping (ANSI B31); and § §  13.51—13.58 (relating to piping, valves and fittings) shall be considered prima facie evidence of compliance with the provisions of this section.

 (b)  Piping systems between storage tanks and dispensing devices at service stations shall be installed underground.

   The provisions of this §  13.52 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (63487) and (5141).

 (a)  Material for piping, valves, or fittings shall be of steel or nodular iron except as set forth in subsections (b) and (c). Nodular iron shall conform to ASTM A395-77, Ferritic Ductile Iron Pressure Retaining Castings for Use at Elevated Temperatures.

 (b)  Materials other than steel or nodular iron may be used underground or if required by the properties of the flammable or combustible liquid handled.

 (c)  Materials other than steel or nodular iron shall be designed to specifications embodying principles recognized as good engineering design for the material used and shall be approved by the fire marshal.

 (d)  When low melting point materials such as aluminum and brass, or materials that soften on fire exposure such as plastic, or nonductile materials such as cast iron are necessary, special consideration shall be given to their behavior on fire exposure. If such materials are used in aboveground piping systems or inside buildings, they shall be suitably protected against fire exposure or so located that any spill resulting from the failure of these materials do not unduly expose persons, buildings, or structures, and are readily controlled by remote valves.

   The provisions of this §  13.53 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (5141).

 (a)  Joints shall be made liquid-tight and shall be either welded, flanged or threaded, except that listed flexible connectors may be used. Threaded joints shall be made up tight with a suitable thread sealant or lubricant. Joints in piping systems handling class I liquids shall be welded when located in concealed spaces within buildings.

 (b)  Pipe joints dependent upon the friction characteristics or resiliency of combustible materials for mechanical continuity or liquid-tightness of piping shall not be used inside buildings. They may be used outside of buildings above or below ground. If used aboveground outside of buildings, the piping shall either be secured to prevent disengagement at the fitting, or the piping system shall be so designed that any spill resulting from disengagement could not unduly expose persons, important buildings or structures, and could be readily controlled by remote valves.

   The provisions of this §  13.54 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5141) to (5142).

 Piping systems shall be substantially supported and protected against physical damage and excessive stresses arising from settlement, vibration, expansion, or contraction. The installation of nonmetallic piping shall be in accordance with the manufacturer’s instructions.

   The provisions of this §  13.55 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial page (5142).

 Corrosion protection for the tank and its piping shall be provided for by one or more of the following methods:

   (1)  Use of protective coatings or wrappings.

   (2)  Cathodic protection.

   (3)  Corrosion resistant materials of construction.

 Piping systems shall contain a sufficient number of valves to operate the system properly and to protect the plant. Piping systems in connection with pumps shall contain a sufficient number of valves to control properly the flow of liquid in normal operation and in the event of physical damage. Each connection to piping by which equipment such as tank cars, tank vehicles or marine vessels discharge liquids into storage tanks shall be provided with a check valve for automatic protection against back-flow if the piping arrangement is such that back-flow from the system is possible.

   The provisions of this §  13.57 amended June 22, 1984, effective June 18, 1984, 14 Pa.B. 2131. Immediately preceding text appears at serial pages (5142) and (63490).

   All piping before being covered, enclosed, or placed in use shall be tested hydrostatically, with air pressure, or by other methods approved by the fire marshal. If piping is tested hydrostatically, the test pressure shall be 150% of the maximum anticipated pressure of the system. If piping is tested pneumatically the test pressure shall be 110% of the maximum anticipated pressure of the system, but not less than 5 psig at the highest point of the system. A pneumatic test shall include a preliminary check at not more than 25 psig The pressure shall be increased gradually in steps providing sufficient time to allow the piping to equalize strains during the test and to check for leaks. The test shall be maintained for at least ten minutes with no drop in pressure or for sufficient time to complete visual inspection of all joints and connections.

   This section cited in 37 Pa. Code §  13.8 (relating to vents); 37 Pa. Code §  13.26 (relating to testing); 37 Pa. Code §  13.51 (relating to scope and application); 37 Pa. Code §  13.52 (relating to general design specifications); and 37 Pa. Code §  13.161 (relating to general provisions).