NOTE: The information contained in this section is for information only. Workers using, transporting or handling propane and/or using propane torches or burners related to roofing operations must complete appropriate propane transportation, handling, and/or torch safety course(s) resulting in appropriate certification.

Propane is the most commonly used liquefied petroleum gas used in roofing operations. It is a by-product of petroleum refining and natural gas processing which is packaged under pressure in various sized cylinders or tanks.

Propane is a clean-burning fuel that is very convenient for contractors to use. However, each year the roofing industry reports numerous accidents involving propane. In most cases, these accidents are caused by poorly trained personnel and/or poorly maintained equipment.

Propane is a non-toxic, non-poisonous, odorless and invisible gas. An identifying odorant called Ethyl Mercaptan is added to propane so that any leaks can easily be detected. This odor is similar to boiled cabbage or rotten eggs.

In the stored state, propane is a liquid but is released from a vapour withdrawal type cylinder or tank as a gas. The boiling point of propane, the point at which the liquid changes to a vapour (gas) is -42.2°C (-44°F). If the surrounding air temperature is above this, gas will form in the upper part of the cylinder.

When gas is drawn from the container at a fast rate, cylinder pressure and temperature are reduced causing frost build-up on the cylinder’s exterior.