ATOMIC ENERGY REGULATORY BOARD

The Mission of the AERB is to ensure the use of ionizing radiation and nuclear energy in India does not cause unacceptable impact on workers, members of the public and to the environment.

Functions of AERB

·         Develop safety policies in both radiation and industrial safety areas:

·      Develop Safety Codes, Guides and Standards for sitting, design, construction, commissioning, operation and decommissioning of different types of nuclear and radiation facilities.

·         Ensure compliance of the regulatory requirements prescribed by AERB during all stages of consenting through a system of review and assessment, regulatory inspection and enforcement.

·         Prescribe the acceptance limits of radiation exposure to occupational workers and members of the public and approve acceptable limits of environmental releases of radioactive substances.

·       Take such steps as necessary to keep the public informed on major issues of radio logical safety significance.

Special definitioins

Cone: A device by which X-ray beam is confined to a specified area, size or dimension.

Detector: A device element of a detector unit or array which receives X-rays and responds by producing an electrical or light signal. The entire assembly of X-ray receiver may contain a single element of a detector or an array of detectors.

Focus: That area of the anode in an X-ray tube on which X-ray-producing electrons are incident.

Kilovolt Peak (kVp): The peak kilo-voltage applied across an X-ray tube.

Milliampere (mA) :A measure of the electric current through X-ray tube (also called tube current).

Noise: A point-to-point variation in image density that does not contain useful information.

Signal-to-Noise Ratio: The ratio of strength of the signal for information content in the image-to-noise level.

X-ray Equipment or X-ray Unit: The integrated assembly consisting of X-ray tube along with its housing, supporting structures, associated accessories necessary for proper operation, and inclusive of built-in radiation safety devices.

Dental X-Ray Equipment

Focus-to-Skin Distance

(a) Dental X-ray assemblies for use with intra-oral films shall be provided with dental cones ensuring the minimum focal spot to skin (FSD) distance as given in the following table:

MINIMUM FOCAL SPOT TO SKIN DISTANCES FOR DENTAL X-RAY ASSEMBLIES

Maximum rated tube potential (kVp)	Minimum focus-to-skin distance (cm)
Between 50 and 60	10
Above 60 and up to and including 75	20

(b) In case of orthopan tomography (OPG) equipment for dental panoramic tomography, the focus-to-skin distance shall be not less than 15 cm.

Dental Cones

(a) X-ray tube shall be provided with such cones that will limit the beam diameter to less than 7.5 cm at the distance specified at the cone end. Interchangeable cones with built-in diaphragm shall be marked with the diameter of cross-section of the useful beam at FSD.

(b) In case of OPG, the protective shielding to attenuate the transmitted radiation shall form an integral part of the equipment.

Control Panel

Control panel shall be provided with means to indicate and control the exposure parameters such as tube potential (kVp), tube current (mA), and beam “ON” and “OFF”.

Cable Length

X-ray unit shall be provided with an electrical cable, which shall be connected to the operating switch at its end. Its length shall be such that the operating switch can be operated from a minimum distance of 2 m from the nearest position of X-ray tube

room layout for an x-ray installation

Location of X-Ray Installation Rooms housing diagnostic X-ray units and related equipment shall be located as far away as feasible from areas of high occupancy and general traffic, such as maternity and pediatric wards and other departments of the hospital that are not directly related to radiation and its use. In case the installation is located in a residential complex, it shall be ensured that:

(i)                   wall(s) of the X-ray rooms on which primary X-ray beam falls is (are) not less than 35 cm thick brick or equivalent,

(ii)                 walls(s) of the X-ray room on which scattered X-ray fall is (are) not less than 23 cm thick brick or equivalent, and

(iii)                there is a shielding equivalent to at least 23 cm thick brick or 1.7 mm lead in front of the door(s) and windows of the X-ray room to protect the adjacent areas, either used by general public or not under possession of the owner of the X-ray room.

Shielding

Appropriate structural shielding shall be provided for walls, doors, ceiling and floor of the room housing the X-ray unit so that doses received by 20 workers and the members of public are kept to the minimum and shall not exceed the respective annual effective doses as prescribed by the competent authority.

Openings and Ventilation

Unshielded openings in an X-ray room for ventilation or natural light shall be located above a height of 2m from the finished floor level outside the X-ray room.

Requirements for Registration to use/operate X-ray equipment.
Type of X-ray unit	Requirements for Layout to install X-ray equipment			Documents to be submitted along with the Registration application
	Min. dimension requirement	Min. area requirement	Layout requirements
OPG	Any single dimension should not be less than 3 m	13 m2	-AERB Type approved X-ray unit - 23cm thick brick walls - 1.7 mm Lead lined doors - Mobile protective barrier with lead glass viewing window of 1.7 mm Pb equivalent	-Copy of layout ( already approved or due for approval) for installation of X-ray unit - Copy of valid NOC/ Type Approval certificate - Copy of RSO approval, if obtained - List of Protective accessories ( Lead apron of 0.25mm etc )
C-arm/Mobile/ Intra Oral Dental equipment	Not Applicable	Not applicable	- AERB Type approved X-ray unit	- Copy of valid NOC/ Type Approval certificate - Copy of RSO approval, if obtained - List of Protective accessories (Lead apron of 0.25mm etc)