The shielding of the door requires about 10kg/m2 sheet lead. The doors that lead to x-ray rooms should have not less than 15 kg/m2 lead. The frame of the entries is excluded from the requirement. For the necessary and maximum protection to be achieved, it is required that the steel door frames should be trifled to overlap the wall structure. An x-ray inspector service should visit the dental facility to monitor the operations, check records and perform test concerning the installation of the use of x-ray equipment to check for its compliance with the radiography Act.
Furthermore, to ensure proper radiation guidance act, According to a report of the National Council on Radiation Protection and Measurements(NCRP) published by the Conference of Radiation Control Program Directors (CRCPD):
- Rule 36(4) of the Rules necessitates protective barriers to be used with a weekly radiation shielding design objective of 0.1 mSv for persons in controlled or open areas and 0.02 mSv for persons in uncontrolled open araeas.
- The distance of the occupied area of interest should be from the source to the nearest possible approach of a person sensitive organs. For a wall, this may be assumed to be not above 0.3 m. For a source situated above potentially occupied spaces, the distance can be placed on not more than 1.7 m beyond the lower floor. Also, for ceiling transmission, a distance of at least 0.5 m above, the floor of the room above is appropriate. (NCRP Report 147, Section 4.1.2)
- According to the rules, operator barriers should be designed to be the main protective barriers and to provide protection equivalent to at least 1/16-inch lead.
- Medical, dental and veterinary radiation facilities shielded in accordance with recommendations contained in NCRP Reports No. 145, No. 147, and No. 148 (NCRP, 2003a; 2004a; 2004b) (i.e., designed should not exceed an effective dose of 1 mSv per year to the maximally exposed individual in an uncontrolled area). According to the NCRP in Statement 10 of December 2004, It necessary to provide adequate protection to employees and members of the public when accessing the uncontrolled areas. An effective dose for uncontrolled regions that does not exceed 1 mSv per year is resonable, based on the NCRP in Statement 10, by the conventional safe assumptions used in the recommended shielding design approach.
- Based on ICRP (1991), NCRP (1993) and Rule 60(1) recommendations for the yearly limit of effective dose to a member of the general public, shielding designs shall limit exposure of all individuals in open uncontrolled areas to an effective dose that does not exceed 1 mSv each year. Following a review of the application of the guidance in NCRP (1993) to medical radiation facilities, NCRP has concluded that a suitable source control for shielding individuals in open areas in or near medical radiation facilities is an effective dose of 1 mSv in each year [see Section 1.4.2 of NCRP Report # 147]. Based on the NCRP in Report 147, this recommendation can be achieved for the medical radiation facilities covered in and designed to meet Reports No. 145, No. 147, and No. 148 with a weekly shielding design aim of 0.02 mGy air kerma (i.e., an annual air-kerma value of 1 mGy) for uncontrolled open areas.
- Vertical barriers must go beyond the floor to a minimum height of 7 feet. Yet, if it is necessary to add additional shielding to the ceiling of the room, then the shielding in the walls must be extended above the 7-foot height to overlap the ceiling shielding. Also, if there is a multi-story building in close proximity of the x-ray room, and if that building has occupied space that could be exposed to scatter or secondary radiation that is not attenuated by the 7-foot-high wall shielding, then additional shielding may be necessary to protect that occupied space.