Liquefied Petroleum Gas (LPG)

Exponent's capabilities include fire investigations, system failure analyses, facility inspections and safety audits, environmental impact studies and consequence modeling. We can also model fire radiation and vapor dispersion hazard zones. We provide services in process safety and construction management. We routinely assist our clients in solving performance-based design challenges and in providing technical support for regulatory applications. Exponent also provides post-incident root cause analysis and litigation support when needed.

Exponent has broad experience with the LPG industry and assists clients with:


  • Thermal and functional testing
  • Engineering design reviews
  • Loss investigations
  • Third-party evaluations, research, and development
  • Process safety/hazard assessments

Liquefied Petroleum Gas (LPG) is produced from natural gas or refining of petroleum. It is a nontoxic and odorless hydrocarbon that is used as a fuel for motorized transport as well as for a wide variety of field and industrial applications. It is also used as a propellant for aerosols and as a refrigerant. Approximately 55% of LPG is produced by natural gas refining, with the remainder from crude oil refining. LPG consists primarily of a mixture of propane and butane.

LPG is produced at refineries, then typically stored underground before being fed to a pipeline station and terminal system or ocean tanker for long-distance distribution. Once at a terminal, LPG is transferred to a bulk transport truck or rail car for short-haul transport to a retail plant. From there, it is distributed in cylinders or bulk trucks for delivery to the retail customer. Cylinders are typically constructed to ASME or DOT standards, and must be tested and requalified at periodic intervals. LPG can also be refrigerated to reduce its vapor pressure. Refrigerated LPG containers are typically constructed to API 620 specifications.

With a boiling point of approximately -44 F, LPG must be pressurized to remain in liquid form. LPG vapor has a specific gravity of approximately 1.7 so it will concentrate in low areas if released. It ignites at around 910 F and produces approximately 93,000 BTU per gallon when burned. The liquid expands when heated, and containers must be filled to less than full capacity and provide a means of pressure relief to prevent vessel rupture.

Several codes and standards apply to the production and distribution of LPG, including:


  • National Fire Protection Association (NFPA) 58 – Liquefied Petroleum Gas Code
  • NFPA 54/ANSI Z223.1 – National Fuel Gas Code
  • American Society of Testing and Materials (ASTM) D1835 – Standard Specification for LPG
  • American Petroleum Institute (API) 2510 – Design and construction of LP-Gas Installations
  • Code of Federal Regulations (CFR) Title 49, Transportation

Liquefied Petroleum Gas (LPG) is produced from natural gas or refining of petroleum. It is a nontoxic and odorless hydrocarbon that is used as a fuel for motorized transport as well as for a wide variety of field and industrial applications. It is also used as a propellant for aerosols and as a refrigerant. Approximately 55% of LPG is produced by natural gas refining, with the remainder from crude oil refining. LPG consists primarily of a mixture of propane and butane.

LPG is produced at refineries, then typically stored underground before being fed to a pipeline station and terminal system or ocean tanker for long-distance distribution. Once at a terminal, LPG is transferred to a bulk transport truck or rail car for short-haul transport to a retail plant. From there, it is distributed in cylinders or bulk trucks for delivery to the retail customer. Cylinders are typically constructed to ASME or DOT standards, and must be tested and requalified at periodic intervals. LPG can also be refrigerated to reduce its vapor pressure. Refrigerated LPG containers are typically constructed to API 620 specifications.

With a boiling point of approximately -44 F, LPG must be pressurized to remain in liquid form. LPG vapor has a specific gravity of approximately 1.7 so it will concentrate in low areas if released. It ignites at around 910 F and produces approximately 93,000 BTU per gallon when burned. The liquid expands when heated, and containers must be filled to less than full capacity and provide a means of pressure relief to prevent vessel rupture.

Several codes and standards apply to the production and distribution of LPG, including:


  • National Fire Protection Association (NFPA) 58 – Liquefied Petroleum Gas Code
  • NFPA 54/ANSI Z223.1 – National Fuel Gas Code
  • American Society of Testing and Materials (ASTM) D1835 – Standard Specification for LPG
  • American Petroleum Institute (API) 2510 – Design and construction of LP-Gas Installations
  • Code of Federal Regulations (CFR) Title 49, Transportation

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