LP (Propane) Tanks - Various Suppliers Informative - Grilling Season Is Here - Beware Of Potentially Dangerous LP Tanks
Now that grilling season is upon us, many of us will be running down to the corner store and exchanging our empty gas grill bottle for a freshly refilled one.
But inspect that new tank carefully - apparently, the folks out there running Meth labs have been using some of these LP tanks for the storage of Anhydrous Ammonia that's used in their Meth processing. They are then returning these contaminated tanks to local stores and exchanging them. Some of these tanks are getting refilled and being sent back into the market.
The trace amounts of Ammonia in the tank will cause rapid disintegration of your grill from the inside out, but more importantly, it will degrade the valve at the top of the cylinder - with potentially disastrous results.
A contaminated valve will have a blue-green color to it, almost like aged copper. You might also notice the smell of ammonia around the tank. If you encounter one of the tanks - LEAVE IT ALONE and call your local fire department immediately.
There is more info, as well as photos of the valves in question at the Propane Gas Assocation's web site -