Propane Filling Station

Background:
First the disclaimer:
These pages are for informational purposes only. PROPANE GAS IS AN EXTREMELY FLAMMABLE GAS UNDER PRESSURE! I am in no way responsible for what you do with this information. YOU are responsible for what you do with the information and YOUR actions. There are regulations that apply when handling propane and for good reason!

Since I have a vehicle, portable welder, foundry, and generator that run on propane I need a propane filling station. I use so much it's just not practicle to be running to the filling station all the time. The biggest problem I had was the availability during late evenings or on Sundays. The convenience stores are usually open, but no trained personel to fill tanks. There's always exchange but they are just rediculous on their prices, and I don't like exchanging my tanks. I bought mine brand new and I know where they've been, and that they've been handled properly. One other thing with some of these filling stations is probably lack of proper training. For instance, you go and have your grill tank filled, the attendant puts it on the scale, hooks up the hose and starts filling. Well, they are supposed to stop filling as soon as the scale tips, but instead of shutting the valve off they ignore the scale and keep filling until the OPD valve shuts off the flow. I've seen this happen lots of times, and it is not the correct procedure. The OPD is a safety device to prevent overfilling, not to be used as full indicator. If that device would fail the result would be overfilling the tank in the case of someone ignoring the scale as was the case with my neighbor a while back. He had taken his tank and had it filled. Later that afternoon he came over and told me that when he hooked it up to his grill the regulator was freezing up. Luckily he shut it off after seeing this. I told him it had been overfilled and it had to be moved to a safe area where we could bleed off the excess gas. Had he not asked me about it, that tank could have heated up on the grill causing the safety to release the excess pressure, and it would have been a big fire. so next time you have a tank filled and they ignore the scale you need to tell them to stop.

The Details:
There are a couple of ways you can setup a dispensing system for filling cylinders. First you need the proper training in propane dispensing. In most cases you can contact your gas supplier and they can provide you with a dispensing unit and the training you need to operate it. If you are capable of setting up the system with your own equipment then there are some regulations you will need to follow. All equipment, tanks, plumbing, and hoses must meet the requirements of NFPA 58. To give you an idea some of the requirements are:
-All threaded piping must be at least schedule 80.
-You need a hydrostatic relief valve where liquid could get trapped between 2 valves.
-Properly sized excess flow valve at the tank before the shutoff valve
-Explosion proof motors, switches and connections
-Emergency shutoff switch located away from the pump to shut it down in case of an emergency.
-Hoses must be rated for LP service, be made of a compatible material (yes certain types of materials are incompatible) be rated at 1750 psi burst pressure and 350 psi working pressure, tested at 420 psi and the dispensing valve must be also rated for LP service and have a pressure rating of 400 psi.
This is not a complete list. Your gas supplier will inspect the system and do a pressure and leak test before filling the tank. If it does not meet the requirements they will not fill it.