Safe Dispensing of Propane - Propane Dispensing Unit Operator Training Manual

		SECTION 2 Safe Dispensing of Propane
		OUTSIDE TEMPERATURE AFFECTS PROPANE

PROPANE WEIGHT -- One gallon of propane weighs 4.2 pounds. HOW OUTSIDE TEMPERATURE AFFECTS PROPANE Temperature has a direct relationship to propane pressure. A pot of water placed on a stove at a high temperature will eventually boil over. In the same way, an increase in outside temperatures will cause an increase in the pressure in an LP gas container. As the pressure increases, the volume of the liquid will also expand in the container. For example, water expands 2.2 %. At a temperature rise from 160 ° F to 600 ° F, liquid propane would expand 25 % and steel would expand only 0.19 %. The fact that propane reacts more quickly to outside temperature changes and expands more rapidly emphasizes the importance of NEVER overfilling an LP gas container.
		No LP gas container should ever be filled more than 80% full.

PROPANE REACTS TO OUTSIDE TEMPERATURES

PROPANE RANGE OF FLAMMABILITY
Range of flammability is a term used to describe that certain mixture of air and LP gas, which will readily burn. Any mix outside this range will not burn easily. Propane has a relatively narrow range of flammability when compared to other petroleum products. It has a flammable range of 2.15 to 9.60. This means if propane is released to the atmosphere, a propane/air mixture containing less than 2.15 % gas is too lean to burn. If the mixture contains more than 9.6% gas, it is too rich to burn.

This range of flammability is important to remember when LP gas is being transferred or discharged. If the propane/air mixture is within the flammability range, sources of ignition could include fans, electrical switches, auto ignition, static electricity, or cigarettes.

PROPANE REACTS TO OUTSIDE TEMPERATURES