What is “LP gas?” The “LP” stands for "liquefied petroleum." A widely used fuel, LP gas is a mixture of light hydrocarbons, predominantly any of the following or mixtures of them; propane, propylene, butanes and butylenes, which are gaseous at atmospheric pressure and temperature. Because of its absence of sulfur and its very low production of nitrogen oxides (NOx), this fuel produces low levels of toxic substances and particulates during combustion. NOx emissions are nitric oxides and nitrogen dioxides. LP gas can be easily liquefied by modestly decreasing the temperature or increasing the pressure. This makes it extremely easy to store and transport, even to remote areas.
The Occupational Safety and Health Administration (OSHA) addresses the storage and handling of LP gas in 29 Code of Federal Regulations (CFR) 1910.110.The National Fire Protection Association (NFPA) standard on LP gas, NFPA 58 Liquefied Petroleum Gas Code, covers the storage, handling, transportation, and use of LP gas. This Code was last revised in 2017.
This document focuses on the proper storage and use of portable LP gas containers - cylinders of 1,000-pounds water capacity or less at user locations – as outlined by OSHA and the NFPA.
The most common type of LP Gas container is the propane cylinder, commonly referred to as a “bottle.” Most of us are familiar with the propane bottles used to fuel gas grills. We are also familiar with the cylinders used to power forklifts.
LP Gas Cylinders Specifications
All LP gas cylinders have the same operational and safety mechanisms in place. These include:
- Relief valves
- Service valves
- Bleeder valves
- Stamped markings or nameplates
- Protective collars / neck rings
- Foot rings
The valves on LP gas cylinders must be protected by a protective cap or collar, also called a neck ring. An unprotected valve hit hard enough can break off allowing liquid gas to escape at a dangerously fast rate. The escaping gas can act as propulsion for the cylinder allowing it to become a dangerous projectile.
The bottom of all propane cylinders are required to have a foot ring. The foot ring ensures that the cylinder stands in an upright and level position.
Most LP gas cylinders are made of steel and therefore they are subject to rusting. The most common place rust is found is on the bottom of the cylinder and around the foot ring. It is important to keep those areas clean and dry.
Storage and Use
OSHA and NFPA guidelines for storing and using LP gas:
- Minimize exposure to excessive temperature rise, physical damage or tampering - store cylinders in an open-air storage unit or cage with a protective roof overhead
- Cylinders stored inside must not be located near exits, stairways, or in areas normally used, or intended to be use, for the safe exit of people.
- In buildings not frequented by the public (such as industrial facilities), not more than 300-pounds of LP gas in cylinders can be stored in one location.
- The quantity of LP gas stored in special buildings or rooms must not exceed 10,000-pounds.
- Use and store cylinders in the proper position
- Store cylinders with the relief valve in direct contact with the vapor space in the container
- Cylinders used for forklifts can be stored in either the vertical or horizontal position, but if stored horizontally the relief valve must be positioned at 12 o’clock
- Cylinder valves must be protected - screw-on type caps or collars must be securely in place on all stored cylinders regardless of whether they are full, partially full or empty, and container outlet valves must be closed
- Storage locations must be provided with at least one approved portable B:C rated fire extinguisher
- The required fire extinguisher must be located no more than 50-feet from the storage location.
Other sources of information regarding storage of LP gas cylinders can be obtained from OSHA Standard 29 CFR 1910.101 which covers general requirements regarding compressed gases. It refers to the Compressed Gas Association’s (CGA) Pamphlet P-1– Standard for Safe Handling of Compressed Gases in Containers, which was last updated in 2015. Additional information is available in Quick Tips #136: Gas Cylinder Storage and Handling. And remember, it is always important to check state and local codes and with the local authority having jurisdiction (AHJ).