Some Propane Basics

Propane is a versatile product with wide spread use throughout the world today. As long as it is properly handled and contained it is both very useful and safe to society. If it is improperly handled or contained, the results can be a catastrophic loss through fire or explosion. For these reasons fire and explosions investigators should have some degree of familiarity with propane and propane systems. In addition, investigators should be aware that the laws regulating this product often vary from state to state.

Propane is commonly referred to as LP-Gas or liquefied petroleum gas. Other types of LP-Gases include butane, isobutene, propylene and butylenes.

Propane is the most common type of LP-Gas. It is a liquid when stored under moderate pressures in containers. The pressure of a container of propane is proportional to the temperature of the container. Pre-calculated charts are available from many sources that provide the pressure in a tank for a given temperature. When a valve or regulator opens the pressure drops and the propane near the top of the container vaporizes to a gas. The vaporized gas is then pushed under the pressure of the tank through the piping system to the appliances where it is consumed.

Some cool facts about propane:

• It boils at -44 degrees Fahrenheit. So if it were -45 F outside you could carry it in and pour it from an open bucket like water!
• As propane vaporizes from a liquid to a gas, energy is absorbed from the surroundings. This is why you occasionally see frost forming on LP-Gas containers. It is also why you see "fog" or ice crystals in the air when it is released in the atmosphere.
• Propane gas is approximately 1.5 times heavier than air so it has a tendency to collect and accumulate in low areas. This increases the hazard associated with propane in some cases relative to natural gas, which is only half as heavy as air and has a greater tendency to dissipate.

Because propane is such a widely used product and has the potential to create catastrophic fires and explosions, there are a number of valuable resources that provide useful information to persons of interest.

By far the National Fire Protection Association document NFPA 58 Standard for the Storage and Handling of Liquefied Petroleum Gases is the leading authoritative publication on LP Gases and the systems utilizing these gases. We recommend the "LP-Gases Handbook" published by NFPA. This document contains the entire text of NFPA 58 and provides commentary and explanatory material as to how to apply the provisions of the standard.

If you are interested in other resources related to propane please visit our web site at www.warren-group.com or give us a call and we will be happy to answer your questions.