In a different but related story ... while on a layover in ANC I purchased some air conditioning freon. I assumed it was Non-flammable gas (HAZMAT). I didn't want to get "caught" sneaking it into MEM for my jumpseat home.
I took the package to the local FedEx Office, I asked about shipping "HAZ" ... the conversation went something like this,
"Mr. Mayday Mark, in order to ship hazardous material you must have attended FedEx HAZMAT shipping class." I told them I had ... "And you must have annual recurrent training." I told them I had ... They said all HAZ shipments incur a $20 surcharge. I said OK ... End of conversation.
Easy!