This is from "The Propane Tank Store"When filling your new propane cylinder for the first time, it is different than filling a used tank. When your new tank arrives, be sure to read the manufacturer's special "Purging Instructions" found on an adhesive label attached to the outside of the tank.
Caution: Do not attempt to take your new tank to a gas station or R/V dealer for the first filling and purging.
Go to a certified propane company in your community.
Once this initial process is done, you can fill your tanks any where desired.
Failure to follow these instructions will very likely result in many different problems with filling the tank and the operation of your appliances.
For more information see our blog "Why do propane tanks need to be purged?"