Dikes
(v) Dikes. Where it is necessary to locate a bulk oxygen system on ground lower than adjacent flammable or combustible liquid storage suitable means shall be taken (such as by diking, diversion curbs, or grading) with respect to the adjacent flammable or combustible liquid storage to prevent accumulation of liquids under the bulk oxygen system. (3) Distance between systems and exposures(i) General. The minimum distance from any bulk oxygen storage container to exposures, measured in the most direct line except as indicated in paragraphs (b)(3) (vi) and (viii) of this section, shall be as indicated in paragraphs (b)(3) (ii) to (xviii) of this section inclusive. (ii) Combustible structures. Fifty feet from any combustible structures. (iii) Fire resistive structures. Twenty-five feet from any structures with fire-resistive exterior walls or sprinklered buildings of other construction, but not less than one-half the height of adjacent side wall of the structure. (iv) Openings. At least 10 feet from any opening in adjacent walls of fire resistive structures. Spacing from such structures shall be adequate to permit maintenance, but shall not be less than 1 foot. (v) Flammable liquid storage above-ground. (vi) Flammable liquid storage below-ground. (vii) Combustible liquid storage above-ground. (viii) Combustible liquid storage belowground. (ix) Flammable gas storage. (Such as compressed flammable gases, liquefied flammable gases and flammable gases in low pressure gas holders): (x) Highly combustible materials. Fifty feet from solid materials which burn rapidly, such as excelsior or paper. (xi) Slow-burning materials. Twenty-five feet from solid materials which burn slowly, such as coal and heavy timber. (xii) Ventilation. Seventy-five feet in one direction and 35 feet in approximately 90 direction from confining walls (not including firewalls less than 20 feet high) to provide adequate ventilation in courtyards and similar confining areas. (xiii) Congested areas. Twenty-five feet from congested areas such as offices, lunchrooms, locker rooms, time clock areas, and similar locations where people may congregate. (xiv)-(xvii) [Reserved] (xviii) Exceptions. The distances in paragraphs (b)(3) (ii), (iii), (v) to (xi) inclusive, of this section do not apply where protective structures such as firewalls of adequate height to safeguard the oxygen storage systems are located between the bulk oxygen storage installation and the exposure. In such cases, the bulk oxygen storage installation may be a minimum distance of 1 foot from the firewall. (4) Storage containers(i) Foundations and supports. Permanently installed containers shall be provided with substantial noncombustible supports on firm noncombustible foundations. (ii) Constructionliquid. Liquid oxygen storage containers shall be fabricated from materials meeting the impact test requirements of paragraph UG-84 of ASME Boiler and Pressure Vessel Code, section VIIIUnfired Pressure Vessels1968, which is incorporated by reference as specified in 1910.6. Containers operating at pressures above 15 pounds per square inch gage (p.s.i.g.) shall be designed, constructed, and tested in accordance with appropriate requirements of ASME Boiler and Pressure Vessel Code, section VIIUnfired Pressure Vessels1968. Insulation surrounding the liquid oxygen container shall be noncombustible. (iii) Constructiongaseous. High- pressure gaseous oxygen containers shall comply with one of the following: