The following persons shall not be required, but shall be permitted, to obtain licenses as licensed public weighmasters: (1) law enforcement officers when acting within the scope of their official duties, (2) a person weighing property, produce, commodities, or articles that he or his employer, if any, is either buying or selling, and (3) a person weighing property, produce, commodities, or articles in conformity with the requirements of federal statutes or the statutes of this State relative to warehousepersons or processors. (Added 1967, No. 102, § 48, eff. April 14, 1967.)