6 Colo. Code Regs. § 1007-1-6-B
6B.1 Space Requirements:
6B.1.1 The operator shall be allotted not less than 0.7 m2 (8 ft2) of unobstructed floor space in the booth.
6B.1.2 The operator's booth may be of any geometric configuration with no dimension less than 0.6 m (2 ft).
6B.1.3 The space shall be allotted excluding any encumbrance by the x-ray control panel, such as overhang, cables, or other similar encroachments.
6B.1.4 The booth shall be located or constructed such that unattenuated scatter radiation originating on the examination table or at the wall cassette cannot reach the operator's location within the booth.
6B.2 Structural Requirements:
6B.2.1 The booth walls shall be permanently fixed barriers at least 2 m (6.5 ft) high.
6B.2.2 When a door or movable panel is used as an integral part of the booth structure, it must have an interlock that will prevent an exposure when the door or panel is not closed in its shielding position.
6B.2.3 Shielding shall be provided to meet the requirements of Part 4.
6B.3 Viewing System Requirements:
6B.3.1 Each booth shall have at least one viewing device that will:
(1) Be so placed that the operator can view the patient during any exposure, and
(2) The device shall be so placed that the operator can have full view of any occupant of the room and should be so placed that the operator can view any entry into the room. If any door that allows access to the room cannot be seen from the booth, then that door must have either an interlock controlling the exposure that will prevent the exposure if the door is not closed; or a warning light must be activated at the control panel when the door is opened.
6B.3.2 When the viewing system is a window, the following requirements also apply:
(1) The viewing area shall be at least 0.1 m2 (1 ft2).
(2) The design of the booth shall be such that the operator's expected position when viewing the patient and operating the x-ray system is at least 0.5 m (1.5 ft) from the edge of the booth.
(3) The material constituting the window shall have at least the same lead equivalence as that required in the booth's wall in which it is mounted.
6B.3.3 When the viewing system is by mirrors, the mirror(s) shall be so located as to accomplish the general requirements of 6B.3.1.
6B.3.4 When the viewing system is by electronic means:
(1) The camera shall be so located as to accomplish the general requirements of 6B.3.1.
(2) There shall be an alternate viewing system as a backup for the primary system, unless the x-ray room is not used in the case of viewing system failure.
6 CCR 1007-1-6-B