New Mexico Statutes 57-18-18. Optional licensing
The following may, but are not required to, obtain licenses as weighmasters:
A. a weights and measures officer when acting within the scope of his official duties;
B. a person weighing property, produce, commodities or articles that he or his employer is buying or selling;
C. a person weighing property, produce, commodities or articles in conformity with the requirements of federal statutes;
D. retailers weighing or measuring commodities for sale by them in retail stores directly to consumers except weighing bulk lot commodities on vehicle or hopper scales;
E. persons who measure the amount of oil, gas or other fuels for purposes of royalty computation and payment or for other operations of fuel and oil companies and their retail outlets; or
F. producers of agricultural commodities or livestock, weighing commodities produced or purchased by them or by their producer neighbors, when no charge is made for such weighing, or no signed or initialed statement or memorandum is issued of the weight upon which a purchase or sale of the commodity is based.