As of 2015 no, but that may change. 404A is an HFC refrigerant and does not harm the O-Zone layer so therefore you do not need to have any kind of certification to purchase. However, HFC refrigerants are slowly being phased out due to their high global warming potential. Nothing official has been declared yet but it won’t be long until HFCs are regulated just as CFCs and HCFCs are.
UPDATE as of December of 2016:
It is important to note that as of January 1st, 2018 you WILL need to be certified to purchase HFC refrigerants such as 410A, 134a, and 404A. Click the link on the bottom of the article for the exact wording from the EPA’s website.