28 CFR § 540.42 - Visiting times.
(a) Each Warden shall establish a visiting schedule for the institution. At a minimum, the Warden shall establish visiting hours at the institution on Saturdays, Sundays, and holidays. The restriction of visiting to these days may be a hardship for some families and arrangements for other suitable hours shall be made to the extent practicable. Where staff resources permit, the Warden may establish evening visiting hours.
(b) Consistent with available resources, such as space limitations and staff availability, and with concerns of institution security, the Warden may limit the visiting period. With respect to weekend visits, for example, some or all inmates and visitors may be limited to visiting on Saturday or on Sunday, but not on both days, in order to accommodate the volume of visitors. There is no requirement that every visitor has the opportunity to visit on both days of the weekend, nor that every inmate has the opportunity to have visits on both days of the weekend.