Description Propane Properties Btu per gallon: 91,502 Btu per cubic foot: 2,488 Btu per pound: 21,548 Pounds per gallon: 4.20 Cubic feet per gallon: 36.38 Cubic feet per pound: 8.66 Specific gravity of vapor: 1.50 Specific gravity of liquid: 0.504 Boiling point: -0.44 degrees f Vapor pressure at 0 degrees f: 23.5 psig Vapor pressure at 100 degrees f: 196 psig Chemical formula: C3H8 (3 parts carbon, 8 parts hydrogen) Octane number: 125 Motor fuel r/m: 104 Cubic feet of air required to burn 1 cubic foot of gas: 23.5 Ignition temperature: 920 – 1,120 degrees f Maximum flame temperature: 3,595 degrees f Flashpoint: -156 degrees f Flammability lower flammable limit (l.f.i.): 2.15 Flammability upper flammable limit (u.f.l.): 9.60 Shipping And Hazard Classification Dot shipping name: propane – liquefied petroleum gas Dot hazard class: flammable gas Dot i.d. number: un 1075 Additional Information Motor fuel and ace cylinders Bomb threat response Valves – cylinders and tanks
