Propane 101 (LPG or Liquid Propane Gas)
So why all the tales of accidents and propane lines blowing gas? Actually it was true at one time, but times have changed along with the equipment.
Prior to 1977 the majority of connections between the regulators and the propane containers (pigtail) in RVs were made of copper tubing, and were wound in a coil to take up excess tubing creating the “pigtail” coil appearance, from which they got their name. Copper, being malleable, when strained to breaking will many times reduce the inside diameter of copper tubing, either from stretching, or bending. This can restrict the flow to the point that excess flow check valves, which reduces the pressure in the propane line in case of a break or leak in the line, might not detect excess gas flow. Thus full pressure flow could occur.
In 1977 the code was changed mandating that the connections, or pigtails, between the propane container and the regulator be made of rubber and then thermoplastic tubing, which would not change diameter in a mechanical “accident,” and would activate the excess flow valves reliably when torn apart.
Here is an article in TrailerLife that explains all the things you need to know about propane (LPG)
In the RV world, LP-gas is a main source of energy to power generators and fuel appliances necessary for comfort heating, cooking and refrigeration. “LP” is an abbreviation for liquefied petroleum. The terms “LP-gas” and “LPG” are widely used to describe the hydrocarbons propane and butane, or a mixture of the two. The compounds are similar, but propane is a better fuel source at lower temperatures, making it the choice for use in RVs. Propane is likely to contain small amounts of other hydrocarbons such as butane, propylene and butylene.
LP-gas is produced by processing natural gas and refining crude oil. When LP-gas is placed under modest pressure, it liquefies and can be stored in portable cylinders used on camping trailers and truck campers and in frame-mounted tanks for motorhomes. LP-gas is colorless and odorless. For safety reasons, the chemical ethanethiol, commonly called ethyl mercaptan, is added to provide a distinct odor in the event of a leak.
LP-gas cylinders used on trailers and truck campers are different from the LP-gas tanks used on motorhomes. A DOT cylinder is a removable portable container like those that supply propane for barbecue grills and is built to U.S. Department of Transportation specifications. An ASME tank for motorhomes is a permanently mounted storage container approved by the American Society of Mechanical Engineers.
Read the full article here: