Current through Register Vol. 18, September 20, 2024
(1) The equipment
used in teletherapy shall be as follows:
(a)
The housing shall be so constructed that, at 1 meter from the source, the
maximum exposure rate does not exceed 10 milliroentgens per hour when the beam
control mechanism is in the "off" position. The average exposure rate measured
at a representative number of points about the housing, each 1 meter from the
source, shall not exceed 2 milliroentgens per hour.
(b) For teletherapy equipment installed after
the effective date of this chapter, the leakage radiation measured at 1 meter
from the source when the beam control mechanism is in the "on" position shall
not exceed 0.1% of the useful beam exposure rate.
(c) Adjustable or removable beam-defining
diaphragms shall allow transmission of not more than 5% of the useful
beam.
(d) The beam control
mechanism shall be of a positive design capable of acting in any orientation of
the housing for which it is designed to be used. In addition to an automatic
closing device, the mechanism shall be designed so that it can be manually
returned to the "off" position with a minimum risk of exposure.
(e) The closing device shall be so designed
as to return automatically to the "off" position in the event of any breakdown
or interruption of the activating force and shall stay in the "off" position
until activated from the control panel.
(f) When any door to the treatment room is
opened, the beam control mechanism shall automatically and rapidly restore the
unit to the "off" position and cause it to remain there until the unit is
reactivated from the control panel.
(g) There shall be at the housing and at the
control panel a warning device that plainly indicates whether the beam is "on"
or "off".
(h) The equipment shall
be provided with a locking device to prevent unauthorized use.
(i) The control panel shall be provided with
a timer that automatically terminates the exposure after a preset
time.
(j) Provision shall be made
to permit continuous observation of patients during irradiation.
(2) No individual shall be in the
treatment room during irradiation unless that individual is the patient.
Mechanical restraining or supporting devices shall be used for positioning the
patient, if necessary.
(3)
Teletherapy sources shall be tested for leakage and contamination in accordance
with the procedures described in ARM
37.14.1105(2).
Tests of leakage may be made by wiping accessible surfaces of the housing port
or collimator while the source is in the "off" position and measuring these
wipes for transferred contamination.
Sec.
75-3-201 and
75-3-202,
MCA; IMP, Sec.
75-3-201 and
75-3-202,
MCA;
