Grocery stores interchange refrigerants among stores as needed. Many times the tags are missing. Additionally several tags are missing for the replacement gases. I understand that there is portable refrigerant identifier, Smartec, that can identify all the blends and low pressured refrigerant gases. Any one has used the identifier? What liability do I have if the refrigerant tanks are mis-identified and I top the refrigerant as stated on the tags into the system. The P&T charts are useless in blends. Any other ideas?