Consenting Process for Radiation Facilities - Atomic Energy ...

deliver specified radiation dose to the malignant tissues in order to arrest
further growth and achieve regression, at the same time sparing normal healthy
tissues. Proper planning in terms of beam size, beam direction and other
parameters is necessary to achieve the objective in an optimum manner. Such
a procedure is called teletherapy.
High activity 60 Co or 137 Cs source is used in suitable devices to obtain well
defined gamma ray beams from a distance directed to the region under
treatment. Such a device is called telegamma therapy unit. The gammaknife
system (GKS) is another type of telegamma therapy unit in which
radiation from a number of 60 Co sources are focused at a single point. This is
used for radio surgery where the high radiation doses are delivered precisely
to a small lesion. All the regulatory procedures (as given in subsection 3.5.1)
for telegamma radiation therapy units will be followed for GKS and similar
equipment using radioisotopes.
Check sources are used in radiotherapy facility for checking the functionality
of the radiation measuring equipment such as secondary standard dosimeters.
The regulatory procedure to be followed for procurement of these sources is
same as that for discrete brachytherapy sources (see subsection 3.8.4).
3.5.1.2 Site and Layout Plan Approval
The room housing the telegamma unit should be located at one end of a
hospital and contiguous with other radiation therapy facilities. Basement is
desirable for location of telegamma facilities since the earth can form a cheap
and effective shielding. However, it should be ensured that site should be
free from flooding and high moisture in air. It shall be also ensured that the
floor can take the heavy shielding load of the telegamma unit. The telegamma
unit shall be housed in a room with adequate shielding and access control.
The layout of the telegamma room has to be approved by AERB prior to its
construction. The applicant should also submit the authenticated documents
issued by relevant Government agency showing the status of ownership/lease
of the premises.
The format of the application for obtaining site and layout approval for the
facility is given in Annexure 20.
3.5.1.3 Construction
The construction of the telegamma therapy facility can be started after
obtaining site and layout plan approval (see subsection 3.5.1.2) and no separate
regulatory approval is required for construction. QA manual for construction
should be prepared and implemented so that the requirements as per approved
layout plan by AERB shall be ensured during construction with respect to
material, density and thicknesses.
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