It may be necessary for the Secretary in the performance of his
duties under the Act, to determine in some instances whether a sale or
service is recognized as a retail sale or particular industry. In the
exceptional case where the determination cannot be made on the basis of
common knowledge or readily accessible information, the Secretary may
gather the information needed for the purpose of making such
determinations. Available information on usage and practice in the
industry is carefully considered in making such determinations, but the
``word-usage of the industry'' does not have controlling force; the
Secretary ``cannot be hamstrung by the terminology of a particular
trade'' and possesses considerable discretion as the one responsible for
the actual administration of the Act. (Wirtz v. Steepleton General Tire
Co., 383 U.S. 190; and see 95 Cong. Rec. 12501-12502, 12510.) The
responsibility for making final decisions, of course, rests with the
courts. An employer disagreeing with the determinations of
the Secretary and claiming exemption has the burden of proving in a
court proceeding that the prescribed percentage of the establishment's
sales or services are recognized as retail in the industry and that his
establishment qualifies for the exemption claimed by him. (See Wirtz v.
Steepleton, cited above, and 95 Cong. Rec. 12510.)
