California Code of Regulations › Title 8 - Industrial Relations › Division 1 - Department of Industrial Relations › Chapter 4 - Division of Industrial Safety › Subchapter 1 - Unfired Pressure Vessel Safety Orders › Article 7 - Compressed and Liquefied Natural Gas System › Section 532 - Installation of Aboveground Storage Tanks

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
(a) General.
(1) Storage tanks installed aboveground shall
					 be installed on firm masonry or concrete foundations. Aboveground horizontal
					 tanks shall have no more than 2 points of support longitudinally. Where
					 necessary, tanks shall be securely anchored to prevent floating.
(2) Metallic structural supports, when used,
					 shall be encased in concrete or other material having a fire resistant rating
					 of at least 2 hours when the distance between the lower surface of the tank and
					 the top of the concrete or masonry foundations exceeds 18 inches. In the case
					 of a vertical tank having no more than one opening in the support skirt,
					 interior fire protection of the skirt may be omitted. (Tanks of not more than
					 575-gallon capacity installed in areas having an average snowfall exceeding 18
					 inches may, at the discretion of the Division, be exempt from the provisions of
					 this paragraph.)
(3) Every tank
					 shall be so supported as to prevent the concentration of excessive loads on the
					 tank at the points of support. All foundations and fastenings shall be designed
					 to provide reasonable safety under all imposed loads including wind,
					 earthquake, vibrations, etc. All tanks over 1,200 gallons capacity shall be
					 installed on foundations in such a manner as to permit expansion and
					 contraction.
(4) The valves and
					 other appurtenances on tanks at all bulk plants, if the plant is not otherwise
					 fenced, shall be surrounded by a rugged steel fence or equivalent. Fences which
					 are not of an open mesh type may be used providing they are acceptable to both
					 the local fire department and the Division. The fence required by this Section
					 shall be at least 6 feet in height. Any fence completely surrounding the tank
					 shall be located a minimum distance of 3 feet from the tank. Other tanks shall
					 also be surrounded by a rugged steel fence or equivalent, if in the opinion of
					 the Division a fence is needed to prevent unauthorized tampering. All fenced
					 areas shall be kept locked when unattended.
(5) Aboveground storage tanks shall be
					 protected from impact from trucks, trailers and other vehicles, where such
					 impact is likely or probable, by suitable curbs, fences or posts and railings.
					 Such curbs or fences shall be arranged so that they will not hamper free
					 ventilation around the tanks.
(6)
					 All loading and unloading connections at bulk plants shall be secured to a
					 concrete bulkhead or equivalent designed to withstand the load imposed by the
					 strongest pipe, hose or flexible metal hose, and fittings to be used in the
					 transfer operation without breaking, or 2,000 pounds whichever is greater
					 unless other adequate protection is provided. This bulkhead shall not be
					 located underneath the tank. The loading and unloading connections shall be
					 firmly secured to this bulkhead and the line between the bulkhead and tank
					 shall be installed in a manner to provide for expansion, contraction, jarring,
					 vibration and settling. Such bulkhead shall be located no less than 25 feet
					 from the nearest important building or line of property adjoining that may be
					 built upon. When in the opinion of the Division such bulkhead is necessary for
					 the safety of the place of employment, it shall be required at storage plants
					 other than bulk plants mentioned above.
(7) The fill line on storage tanks shall be
					 equipped with a back-flow check valve to prevent discharge of the natural gas
					 from the receiving tank in case of line, hose or fittings rupture.
(8) A fire extinguisher conforming to the
					 provisions of California Administrative Code, Title 19, Chapter 1, Subchapter
					 3, and having a rating of not less than 20B shall be available and ready for
					 use during the time natural gas is being transferred. The extinguisher carried
					 on a bulk delivery or transportation vehicle may be considered as meeting the
					 requirements of this Order when transferring natural gas from or to such
					 vehicle provided the extinguisher has the required rating listed
					 above.