Liquefied petroleum gas

Scope

29 CFR 1910.110 (Storage and handling of liquefied petroleum gases) applies to your company if you store, use, or have on the premises any material that is composed predominantly of any of the following hydrocarbons, or mixtures: propane, propylene, butanes (normal butane or isobutane), and butylenes. Different sections of the regulation are in effect depending on amounts of the chemical on site.

Exemptions. This regulation does not apply to:

• Marine and pipeline terminals, natural gas processing plants, refineries, or tank farms other than those at industrial sites;
• LPG refrigerated storage systems;
• LPG when used with oxygen. The requirements of 1910.253 apply to such use;
• LPG when used in utility gas plants. (For this usage, the National Fire Protection Association Standard for the Storage and Handling of Liquefied Petroleum Gases at Utility Gas Plants, NFPA No. 59-1968, will apply.); and
• Low-pressure (not in excess of one-half pound per square inch or 14 inches water column) LPG piping systems, and the installation and operation of residential and commercial appliances including their inlet connections, supplied through such systems. (For these systems, the National Fire Protection Association Standard for the Installation of Gas Appliances and Gas Piping, NFPA 54-1969 will apply.)

Regulatory citations

• 29 CFR 1910.110 — Storage and handling of liquefied petroleum gases

Key definitions

• Containers: All vessels, such as tanks, cylinders, or drums, used for transportation or storing liquefied petroleum gases.
• Liquefied petroleum gases (LPG and LP-Gas): Any material which is composed predominantly of any of the following hydrocarbons, or mixtures of them; propane, propylene, butanes (normal butane or isobutane), and butylenes.
• Ventilation, adequate: When specified for the prevention of fire during normal operation, ventilation shall be considered adequate when the concentration of the gas in a gas-air mixture does not exceed 25 percent of the lower flammable limit.

Summary of requirements

Location of containers and regulating equipment.

1. Locate containers, and first stage regulating equipment if used, outside of buildings, except under certain conditions.
2. Place each individual container nearest to the important building or group of buildings (see Table H-23 in 29 CFR 1910.110).
3. Do not stack containers installed for use one above the other.
4. In the case of buildings devoted exclusively to gas manufacturing and distributing operations, the distances required by the table in 2 above may be reduced provided that in no case will containers of water capacity exceeding 500 gallons be located closer than 10 feet to such gas manufacturing and distributing buildings.
5. Readily ignitable material such as weeds and long dry grass must be removed within 10 feet of any container.
6. The minimum separation between liquefied petroleum gas containers and flammable liquid tanks must be 20 feet, and the minimum separation between a container and the centerline of the dike must be 10 feet. These provisions do 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.
7. Suitable means must be taken to prevent the accumulation of flammable liquids under adjacent liquefied petroleum gas containers, such as by diking, diversion curbs, or grading.
8. Do not locate liquefied petroleum gas containers may be located within the diked area.When using dikes with flammable liquid tanks, no
9. Install containers and regulating equipment outside of buildings or structures must not be buried below ground. However, this must not prohibit the installation in a compartment or recess below grade level such as a niche in a slope or terrace wall which is used for no other purpose, providing that the container and regulating equipment are not in contact with the ground and the compartment or recess is drained and ventilated horizontally to the outside air from its lowest level, with the outlet at least three feet away from any building opening which is below the level of such outlet.
10. When operational requirements make portable use of containers necessary and their location outside of buildings or structures is impractical, containers and equipment are permitted to be used inside of buildings or structures in accordance with specific provisions of the regulation.
11. Locate containers, regulating equipment, manifolds, pipe, tubing, and hose as to minimize exposure to abnormally high temperatures (such as may result from exposure to convection or radiation from heating equipment or installation in confined spaces), physical damage, or tampering by unauthorized persons.
12. Locate heat producing equipment must be used in a way that minimizes the possibility of ignition of combustibles.
13. Understand the hazards associated with LPG. LPG is flammable and is considered an asphyxiant. In its liquid form, LPG can cause freezing of tissue upon skin contact. Most manufacturers odorize LPG, so it can be detected. The odor must be detected at one-fifth of LPG’s lower flammable limit.
14. Know the exposure limits: Butane has threshold limit from the American Conference of Governmental Industrial Hygienists (ACGIH) of 800 ppm, and the threshold limit for propane is 1000 ppm.

LP-gas in buildings.

1. Vapor must be piped into buildings at pressures in excess of 20 psig only if the buildings or separate areas thereof are:
   • Constructed in accordance with the regulation;
   • Used exclusively to house equipment for vaporization, pressure reduction, gas mixing, gas manufacturing, or distribution, or to house internal combustion engines, industrial processes, research and experimental laboratories, or equipment and processes using such gas and having similar hazards; or
   • Under construction or undergoing major renovation.
2. Liquid may be permitted in buildings as follows:
   • Buildings, or separate areas of buildings, used exclusively to house equipment for vaporization, pressure reduction, gas mixing, gas manufacturing, or distribution, or to house internal combustion engines, industrial processes, research and experimental laboratories, or equipment and processes using such gas and having similar hazards; and when such buildings, or separate areas thereof are constructed according to the regulation.
   • Buildings, structures, or equipment under construction or undergoing major renovation provided the temporary piping meets conditions of piping in the regulation.
   • Liquid piping inside buildings is kept to a minimum, protected against construction hazards, securely fastened to walls or other surfaces to provide adequate protection from breakage, and located to subject the liquid line to lowest ambient temperatures.
3. Portable containers must not be taken into buildings except when operational requirements make portable use of containers necessary and their location outside of buildings or structures is impractical, containers and equipment are permitted to be used inside of buildings or structures according to specific provisions of the regulation for the following:
   • Portable Engines in Buildings,
   • LP Gas Fueled Industrial Trucks,
   • Garaged LP Gas Fueled Vehicles,
   • Stored Containers Awaiting Use or Resale,
   • Storage Within Buildings Not Frequented By The Public,
   • Storage Within Special Buildings or Rooms.

Tank car or transport truck loading or unloading points. Tank car or transport truck loading or unloading points must be located with due consideration to the following:

• Proximity to railroads and highway traffic.
• With respect to buildings on installer’s property.
• Nature of occupancy.
• Topography.
• Type of construction of buildings.
• Number of tank cars or transport trucks that may be safely loaded or unloaded at one time.
• Frequency of loading or unloading.

The filling pipe inlet terminal must not be located inside a building. For containers with a water capacity of 125 gallons or more, such terminals must be located not less than 10 feet from any building, and preferably not less than 5 feet from any driveway, and must be located in a protective housing built for the purpose.

Storage outside of buildings. Storage outside of buildings, for containers awaiting use or resale, must be located according to Table H-33 of 29 CFR 1910.110 with respect to the nearest important building or group of buildings, and busy thoroughfares.

Containers must be in a suitable enclosure or otherwise protected against tampering.

Technical specifications. Beyond the information listed in this section, the regulation contains detailed technical specifications on the following topics:

Positions involved. Ensure that an employee is in attendance at all times while the tank car, cars, or trucks are being loaded or unloaded.

Reviewing. All piping, tubing, or hose must be tested after assembly and proved free from leaks at not less than normal operating pressures. After installation, piping and tubing of all domestic and commercial systems must be tested and proved free of leaks using a manometer or equivalent device that will indicate a drop in pressure. The test must not be made with a flame.

All LP-Gas service station piping must be tested after assembly and proved free from leaks at not less than normal operating pressures.