Better safe than sorry.
You should have your motor home, travel trailer or fifth-wheel propane system inspected each year by an RV dealer or by a Railroad Commission-licensed propane gas supplier. A technician will check the system for leaks and for proper regulator settings, inspect the valves and fittings and certify that tanks are free from rust and dents. Any damaged equipment should be replaced immediately.
You should also inspect the various propane-operated appliances in your RV, including your refrigerator, stove, furnace, lanterns and other devices. Be sure that the supply lines connecting these appliances to propane tanks are the correct length and properly installed, with no supply lines rubbing against sharp edges or corners.
Properly install a Propane Leak Detector based on manufacturer instructions and check it each time you use of your RV. If you suspect your RV's propane detector isn't working properly, replace it with a new one immediately.
When Full Is Too Full
One of the most common hazards with propane is overfilled tanks. Fortunately, all small propane cylinders (up to 40-lb. capacity) manufactured after September 1998 are equipped with an overfilling protection device (OPD).
Propane tanks equipped with an OPD are designed to be filled only to a certain level, which allows the fuel to expand into the vapor space as the temperature rises. Tanks filled beyond this level may leak excess pressure through the tank's relief valve and into the surrounding air. Or, propane liquid could enter the piping system, resulting in higher than normal pressure to appliances. Both scenarios present a hazard.
If you have an old cylinder, an OPD must be installed. Cylinders without OPDs can no longer be refilled.
When refilling on-board propane cylinders, turn off the RV engine, all appliances, and electronic re-igniters. Make sure no one is in the RV during refueling.
What to Do If You Suspect A Leak
If you smell gas, exit your RV immediately. Don't use electric switches or appliances. Leave the door open to air out the rig. Close the supply valve on the propane tank, and call a propane gas supplier or the fire department.
Proper Identification and Installation
Propane tanks installed in hard-to-see places must be identified by the letters "LPG" in one-inch high or larger letters. The letters must be placed in a visible spot as near the tank as possible.
Propane used with RVs is stored in one of two types of containers: DOT cylinders or ASME tanks. DOT cylinders are typically used on trailers and truck campers and must be installed vertically, while ASME tanks are used on motor homes and must be installed horizontally.
Always have your tanks refilled instead of trading in empty tanks. This ensures you know where your tank has been and how it's been treated.