7 U.S.C. § 79b

(a) Random and periodic testing at least annually; fees The Secretary shall provide for the testing of all equipment used in the sampling, grading, inspection, and weighing for the purpose of official inspection, official weighing, or supervision of weighing of grain located at all grain elevators, warehouses, or other storage or handling facilities at which official inspection or weighing services are provided under this chapter, to be made on a random and periodic basis, under such regulations as the Secretary may prescribe, as the Secretary deems necessary to assure the accuracy and integrity of such equipment. Such regulations shall provide for the charging and collection of reasonable fees to cover the estimated costs to the Secretary incident to the performance of such testing by employees of the Secretary. Such fees shall be deposited into the fund created by section 79(j) of this title. (b) Personnel to conduct testing The Secretary is authorized to cause such testing provided for in subsection (a) to be performed (1) by personnel employed by the Secretary, or (2) by States, political subdivisions thereof, or persons under the supervision of the Secretary, under such regulations as the Secretary may prescribe. (c) Use of non-approved equipment prohibited Notwithstanding any other provision of law, no person shall use for the purposes of this chapter any such equipment not approved by the Secretary.