9 C.F.R. § 592.96
Inspection operating schedules for services performed pursuant to this part shall be requested in writing and approved by the appropriate District Office. Normal operating schedules for a full-week consist of a continuous 8-hour period per day (excluding but not to exceed 1 hour for lunch), 5 consecutive days per week, within the administrative workweek, Sunday through Saturday, for each shift required. Less than 8-hour schedules may be requested and will be approved if inspection program personnel are available. Clock hours of daily operations need not be specified in the request, although as a condition of continued approval, the hours of operation shall consist of a continuous 10-hour period per day (excluding but not to exceed 1 hour for lunch), 4 consecutive days per week, within the administrative workweek, Sunday through Saturday for each full shift required. Inspection program personnel are to be given reasonable advance notice by management of any change in the hours the inspection service is requested.
9 C.F.R. § 592.96