Do these propane tanks need to be parged before being filled with propane ?

It's been too long to remember if purged but today's tanks SAY purged but are not = you spend a bit more time at refilling station while they let the air out then check the valves, then fill it

It is a good idea to purge your cylinder before its first filling even if it has been prepurged. The cost of purging is generally a couple of dollars and purging it will give you piece of mind that everything is good to go from the cylinder perspective.