If your PSM/RMP covered process contains a flammable liquid, 1910.106 has provided us with some regulatory facility siting requirements that we can quickly inspect to ensure we meet the minimum compliance distances. If you have liquefied petroleum gases within your facility, 1910.110 provides some basic siting requirements that should be met to have an argument that the propane will not impact your covered process or how your LPG-covered process should be laid out.
Here are those requirements:
Flammable Liquids (1910.106)
Drainage, dikes, and walls for aboveground tanks
1910.106(b)(2)(vii)(a) 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.
1910.106(b)(2)(vii)(b) Where protection of adjoining property or waterways is by means of a natural or man made drainage system, such systems shall comply with the following:
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1910.106(b)(2)(vii)(b)(2) … drainage system shall terminate in vacant land or other area 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 so located that, if the flammable or combustible liquids in the drainage system are ignited, the fire will not seriously expose tanks or adjoining property.
1910.106(b)(2)(vii)(c) Where protection of adjoining property or waterways is accomplished by retaining the liquid around the tank by means of a dike, the volume of the diked area shall comply with the following requirements:
1910.106(b)(2)(vii)(c)(1) … the volumetric capacity of the diked area shall not be less than the greatest amount of liquid that can be released from the largest tank within the diked area, assuming a full tank. The capacity of the diked area enclosing more than one tank shall be calculated by deducting the volume of the tanks other than the largest tank below the height of the dike.
1910.106(b)(2)(vii)(c)(2) …a tank or group of tanks with fixed roofs containing crude petroleum with boilover characteristics, the volumetric capacity of the diked area shall be not less than the capacity of the largest tank served by the enclosure, assuming a full tank. The capacity of the diked enclosure shall be calculated by deducting the volume below the height of the dike of all tanks within the enclosure.
1910.106(b)(2)(vii)(c)(3) Walls of the 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.
1910.106(b)(2)(vii)(c)(4) The walls of the diked area shall be restricted to an average height of 6 feet above interior grade.
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1910.106(b)(2)(vii)(c)(6) No loose combustible material, empty or full drum or barrel, shall be permitted within the diked area.
Tank vehicle and tank car loading and unloading
1910.106(e)(4)(i) Tank vehicle and tank car loading or unloading facilities shall be separated from aboveground tanks, warehouses, other plant buildings or nearest line of adjoining property which may be built upon by a distance of 25 feet for Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), and 15 feet for Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) and Category 4 flammable liquids, measured from the nearest position of any fill stem. Buildings for pumps or shelters for personnel may be a part of the facility.
Operations of the facility shall comply with the appropriate portions of paragraph (f)(3) of this section.
1910.106(f)(3) “Loading and unloading facilities”
1910.106(f)(3)(i) Separation
Tank vehicle and tank car loading or unloading facilities shall be separated from aboveground tanks, warehouses, other plant buildings or nearest line of adjoining property that may be built upon by a distance of 25 feet for Category 1 or 2 flammable liquids or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), and 15 feet for Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) and Category 4 flammable liquids measured from the nearest position of any fill spout.
Buildings for pumps or shelters for personnel may be a part of the facility.
1910.106(f)(7) Drainage and waste disposal
Provision shall be made to prevent flammable liquids which may be spilled at loading or unloading points from entering public sewers and drainage systems, or natural waterways. Connection to such sewers, drains, or waterways by which flammable liquids might enter shall be provided with separator boxes or other approved means whereby such entry is precluded. Crankcase drainings and flammable liquids shall not be dumped into sewers, but shall be stored in tanks or tight drums outside of any building until removed from the premises.
Processing plants
1910.106(h)(2) Location
1910.106(h)(2)(i) “Classification.” The location of each processing vessel shall be based upon its flammable liquid capacity.
1910.106(h)(3) “Processing building” –
1910.106(h)(3)(i) “Construction.”
1910.106(h)(3)(i)(a) Processing buildings shall be of fire-resistance or noncombustible construction, except heavy timber construction with load-bearing walls may be permitted for plants utilizing only stable Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) or Category 4 flammable liquids. Except as provided in paragraph (h)(2)(ii) of this section or in the case of explosion resistant walls used in conjunction with explosion relieving facilities, see paragraph (h)(3)(iv) of this section, load-bearing walls are prohibited. Buildings shall be without basements or covered pits.
1910.106(h)(3)(i)(b) Areas shall have adequate exit facilities arranged to prevent occupants from being trapped in the event of fire. Exits shall not be exposed by the drainage facilities described in paragraph (h)(ii) of this section.
1910.106(h)(3)(ii) “Drainage.”
1910.106(h)(3)(ii)(a) Emergency drainage systems shall be provided to direct flammable liquid leakage and fire protection water to a safe location. This may require curbs, scuppers, or special drainage systems to control the spread of fire, see paragraph (b)(2)(vii)(b) of this section.
1910.106(h)(3)(ii)(b) Emergency drainage systems, if connected to public sewers or discharged into public waterways, shall be equipped with traps or separators.
1910.106(h)(5) Tank vehicle and tank car loading and unloading
Tank vehicle and tank car loading or unloading facilities shall be separated from aboveground tanks, warehouses, other plant buildings, or nearest line of adjoining property which may be built upon by a distance of 25 feet for Category 1 or 2 flammable liquids or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), and 15 feet for Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) and Category 4 flammable liquids measured from the nearest position of any fill stem. Buildings for pumps or shelters for personnel may be a part of the facility. Operations of the facility shall comply with the appropriate portions of paragraph (f)(3) of this section.
Fire control
1910.106(h)(6)(i) “Portable extinguishers.” Approved portable fire extinguishers of appropriate size, type, and number shall be provided.
1910.106(h)(6)(ii) “Other controls.” Where the special hazards of operation or exposure indicate a need, the following fire control provision shall be provided.
1910.106(h)(6)(ii)(a) A reliable water supply shall be available in pressure and quantity adequate to meet the probable fire demands.
1910.106(h)(6)(ii)(b) Hydrants shall be provided in accordance with accepted good practice.
1910.106(h)(6)(ii)(c) Hose connected to a source of water shall be installed so that all vessels, pumps, and other equipment containing flammable liquids can be reached with at least one hose stream. Nozzles that are capable of discharging a water spray shall be provided.
1910.106(h)(6)(ii)(d) Processing plants shall be protected by an approved automatic sprinkler system or equivalent extinguishing system. If special extinguishing systems including but not limited to those employing foam, carbon dioxide, or dry chemical are provided, approved equipment shall be used and installed in an approved manner.
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1910.106(h)(6)(iv) “Maintenance.” All plant fire protection facilities shall be adequately maintained and periodically inspected and tested to make sure they are always in satisfactory operating condition and that they will serve their purpose in time of emergency.
1910.106(h)(7) “Sources of ignition” –
1910.106(h)(7)(i)(a) Precautions shall be taken to prevent the ignition of flammable vapors. Sources of ignition include but are not limited to open flames; lightning; smoking; cutting and welding; hot surfaces; frictional heat; static, electrical, and mechanical sparks; spontaneous ignition, including heat-producing chemical reactions; and radiant heat.
Electrical
1910.106(h)(7)(iii)(a) All electrical wiring and equipment shall be installed in accordance with subpart S of this part.
1910.106(h)(7)(iii)(b) Locations where flammable vapor-air mixtures may exist under normal operations shall be classified Class I, Division 1 according to the requirements of subpart S of this part. For those pieces of equipment installed in accordance with paragraph (h)(3)(iii)(b) of this section, the Division 1 area shall extend 5 feet in all directions from all points of vapor liberation. All areas within pits shall be classified as Division 1 if any part of the pit is within a Division 1 or 2 classified area unless the pit is provided with mechanical ventilation.
1910.106(h)(7)(iii)(c) Locations where flammable vapor-air mixtures may exist under abnormal conditions and for a distance beyond Division 1 locations shall be classified as Division 2 according to the requirements of subpart S of this part. These locations include an area within 20 feet horizontally, 3 feet vertically beyond a Division 1 area, and up to 3 feet above floor or grade level within 25 feet, if indoors, or 10 feet if outdoors, from any pump, bleeder, withdrawal fitting, meter, or similar device handling Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C). Pits provided with adequate mechanical ventilation within a Division 1 or 2 area shall be classified Division 2. If Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) or Category 4 flammable liquids only are handled, then ordinary electrical equipment is satisfactory, though care shall be used in locating electrical apparatus to prevent hot metal from falling into open equipment.
1910.106(h)(7)(iii)(d) Where the provisions of paragraphs (h)(7)(iii) (a), (b), and (c) of this section require the installation of explosion-proof equipment, ordinary electrical equipment including switchgear may be used if installed in a room or enclosure which is maintained under positive pressure with respect to the hazardous area. Ventilation makeup air shall be uncontaminated by flammable vapors.
Housekeeping
1910.106(h)(8)(i) “General.” Maintenance and operating practices shall be in accordance with established procedures which will tend to control leakage and prevent the accidental escape of flammable liquids. Spills shall be cleaned up promptly.
1910.106(h)(8)(ii) “Access.” Adequate aisles shall be maintained for unobstructed movement of personnel and so that fire protection equipment can be brought to bear on any part of the processing equipment.
1910.106(h)(8)(iii) “Waste and residues.” Combustible waste material and residues in a building or operating area shall be kept to a minimum, stored in closed metal waste cans, and disposed of daily.
1910.106(h)(8)(iv) “Clear zone.” Ground area around buildings and operating areas shall be kept free of tall grass, weeds, trash, or other combustible materials.
Propane (1910.110)
1910.110(b)(6) Location of containers and regulating equipment.
1910.110(b)(6)(i) Containers, and first stage regulating equipment if used, shall be located outside of buildings, except under one or more of the following:…
1910.110(b)(6)(ii) Each individual container shall be located with respect to the nearest important building or group of buildings in accordance with Table H-23.
1910.110(b)(6)(vii) The minimum separation between liquefied petroleum gas containers and flammable liquid tanks shall be 20 feet, and the minimum separation between a container and the centerline of the dike shall be 10 feet. The foregoing provision shall not apply when LP-Gas containers of 125 gallons or less capacity are installed adjacent to Class III flammable liquid tanks of 275 gallons or less capacity.
1910.110(b)(11)(iii)(i) Except as provided in (c) of this subdivision, the following minimum distances shall be maintained between direct fired vaporizers and the nearest important building or group of buildings:
Ten feet for vaporizers having a capacity of 15 gallons per hour or less vaporizing capacity.
Twenty-five feet for vaporizers having a vaporizing capacity of 16 to 100 gallons per hour.
Fifty feet for vaporizers having a vaporizing capacity exceeding 100 gallons per hour.
1910.110(b)(11)(iv)(g)
The following minimum distances shall be maintained between a storage tank heated by a direct fired tank heater and the nearest important building or group of buildings:
Ten feet for storage containers of less than 500 gallons water capacity.
Twenty-five feet for storage containers of 500 to 1,200 gallons water capacity.
Fifty feet for storage containers of over 1,200 gallons water capacity.
1910.110(b)(14)(v) Filling of fuel containers for industrial trucks or motor vehicles from industrial bulk storage containers shall be performed not less than 10 feet from the nearest important masonry-walled building or not less than 25 feet from the nearest important building or other construction and, in any event, not less than 25 feet from any building opening.
1910.110(b)(14)(vii) The filling connection and the vent from the liquid level gages in containers, filled at point of installation, shall not be less than 10 feet in any direction from air openings into sealed combustion system appliances or mechanical ventilation air intakes.
1910.110(b)(15) Tank car or transport truck loading or unloading points and operations.
1910.110(b)(15)(i) The track of tank car siding shall be relatively level.
1910.110(b)(15)(ii) A “Tank Car Connected” sign, as covered by DOT rules, shall be installed at the active end or ends of the siding while the tank car is connected.
1910.110(b)(15)(iii) While cars are on sidetrack for loading or unloading, the wheels at both ends shall be blocked on the rails.
1910.110(b)(15)(iv) The employer shall insure that an employee is in attendance at all times while the tank car, cars, or trucks are being loaded or unloaded.
1910.110(b)(15)(v) A backflow check valve, excess-flow valve, or a shutoff valve with means of remote closing, to protect against uncontrolled discharge of LP-Gas from storage tank piping shall be installed close to the point where the liquid piping and hose or swing joint pipe is connected.
1910.110(b)(15)(vi) Where practical, the distance of the unloading or loading point shall conform to the distances in subparagraph (6)(ii) of this paragraph.
1910.110(d)(7)(iv)(d) Container is located so as not to be subject to vehicular damage, or is adequately protected against such damage.
1910.110(d)(12)(iii) Suitable roadways or means of access for extinguishing equipment such as wheeled extinguishers or fire department apparatus shall be provided.
1910.110(d)(12)(iv) To minimize trespassing or tampering, the area which includes container appurtenances, pumping equipment, loading and unloading facilities, and cylinder-filling facilities shall be enclosed with at least a 6-foot-high industrial type fence unless otherwise adequately protected. There shall be at least two means of emergency access.
1910.110(d)(14)(ii) In industrial installations involving containers of 150,000 gallons aggregate water capacity or more, provision shall be made for an adequate supply of water at the container site for fire protection in the container area, unless other adequate means for fire control are provided. Water hydrants shall be readily accessible and so spaced as to provide water protection for all containers. Sufficient lengths of firehose shall be provided at each hydrant location on a hose cart, or other means provided to facilitate easy movement of the hose in the container area. It is desirable to equip the outlet of each hose line with a combination fog nozzle. A shelter shall be provided to protect the hose and its conveyor from the weather.