37 Tex. Admin. Code § 259.746
Safety vestibules shall be provided for each inmate living area and day room used for confinement of three or more inmates with no more than three cells being served by one vestibule. All primary entrances to the security perimeter shall be provided with a safety vestibule.
Source Note:The provisions of this §259.746 adopted to be effective September 2, 1997, 22 TexReg 8405.