| April, 1994, or Task Group 142 report: Quality Assurance
of Medical Accelerators, published by American Association of Physicists
in Medicine on August 17, 2009, are accepted as an established protocol.
At a minimum, the spot check protocol shall include items in subclauses
(III) - (VI) of this clause.
(II) If a licensed medical physicist does not perform
the spot check measurements, the results of the spot check measurements
shall be reviewed by a licensed medical physicist at a frequency not
to exceed 5 treatment days and a record kept of the review. If the
output varies by more than 3.0% from the expected value, a licensed
medical physicist shall be notified immediately.
(III) The written spot check procedures shall specify
the frequency at which tests or measurements are to be performed and
the acceptable tolerance for each parameter measured in the spot check
when compared to the value for that parameter determined in the calibration.
(IV) Where a system has built-in devices that provide
a measurement of any parameter during irradiation, such measurement
shall not be utilized as a spot check measurement.
(V) A parameter exceeding a tolerance set by a licensed
medical physicist shall be corrected before the system is used for
patient irradiation.
(VI) Whenever a spot check indicates a significant
change in the operating characteristics of a system, as specified
in a licensed medical physicist's written procedures, the system shall
be recalibrated, as required in this clause of this subparagraph.
(VII) Records of spot check measurements and any necessary
corrective actions shall be maintained by the registrant in accordance
with subsection (l) of this section for inspection by the agency.
(VIII) Spot checks shall be obtained using a system
satisfying the requirements of clause (ii)(III) of this subparagraph.
(iv) Facilities with therapeutic radiation machines
with energies of 1 MeV and above shall procure the services of a licensed
medical physicist with a specialty in therapeutic radiological physics.
(I) The physicist shall be responsible for:
(-a-) calibration of radiation machines;
(-b-) supervision and review of beam and clinical dosimetry;
(-c-) measurement, analysis, and tabulation of beam
data;
(-d-) establishment of quality assurance procedures
and performance of spot check review; and
(-e-) review of absorbed doses delivered to patients.
(II) The licensed medical physicist described in subclause
(I) of this clause shall also be available and responsive to immediate
problems or emergencies.
(4) Radiation therapy simulators.
(A) General requirements. In addition to the general
requirements in paragraph (1)(B), (C), (F), and (H) of this subsection,
radiation therapy simulators shall comply with the following:
(i) Technique chart. A technique chart relevant to
the particular radiation machine shall be provided or electronically
displayed in the vicinity of the console and used by all operators.
(ii) Operating and safety procedures. Each registrant
shall have and implement written operating and safety procedures in
accordance with paragraph (1)(G) of this subsection.
(iii) Protective devices. When utilized, protective
devices shall meet the following requirements.
(I) Protective devices shall be made of no less than
0.25 mm lead equivalent material.
(II) Protective devices, including aprons, gloves,
and shields shall be checked annually for defects, such as holes,
cracks, and tears. These checks may be performed by the registrant
by visual, tactile, or x-ray imaging. If a defect is found, equipment
shall be replaced or removed from service until repaired. A record
of this test shall be made and maintained by the registrant in accordance
with subsection (l) of this section for inspection by the agency.
(iv) Viewing system. Windows, mirrors, closed circuit
television, or an equivalent system shall be provided to permit the
operator to continuously observe the patient during irradiation. The
operator shall be able to maintain verbal, visual, and aural contact
with the patient.
(v) Operator position. The operator's position during
the exposure shall be such that the operator's exposure is as low
as reasonably achievable (ALARA) and the operator is a minimum of
6 feet from the source of radiation or protected by an apron, gloves,
or other shielding having a minimum of 0.25 mm lead equivalent material.
(vi) Holding of tube. In no case shall an individual
hold the tube or tube housing assembly supports during any radiographic
exposure.
(vii) No individuals other than the patient and the
operator(s) shall be in the treatment room during operation of the
simulator.
(viii) Film processing.
(I) Films shall be developed in accordance with the
time-temperature relationships recommended by the film manufacturer.
The specified developer temperature for automatic processing and the
time-temperature chart for manual processing shall be posted in the
darkroom. If the registrant determines an alternate time-temperature
relationship is more appropriate for a specific facility, that time-temperature
relationship shall be documented and posted.
(II) Chemicals shall be replaced according to the chemical
manufacturer's or supplier's recommendations or at an interval not
to exceed 3 months.
(III) Darkroom light leak tests shall be performed
and any light leaks corrected at intervals not to exceed 6 months.
(IV) Lighting in the film processing/loading area shall
be maintained with the filter, bulb wattage, and distances recommended
by the film manufacturer for that film emulsion or with products that
provide an equivalent level of protection against fogging.
(V) Corrections or repairs of the light leaks or other
deficiencies in subclauses (II), (III), and (IV) of this clause shall
be initiated within 72 hours of discovery and completed no longer
than 15 days from detection of the deficiency unless a longer time
is authorized by the agency. Records of the correction or repairs
shall include the date and initials of the individual performing these
functions and shall be maintained in accordance with subsection (l)
of this section for inspection by the agency.
(VI) Documentation of the items in subclauses (II),
(III), and (V) of this clause shall be maintained at the site where
performed and shall include the date and initials of the individual
completing these items. These records shall be kept in accordance
with subsection (l) of this section for inspection by the agency.
(ix) Alternative processing systems. Users of daylight
processing systems, laser processors, self-processing film units,
or other alternative processing systems shall follow manufacturer's
recommendations for image processing. Documentation that the registrant
is following manufacturer's recommendations shall include the date
and initials of the individual completing the document and shall be
maintained at the site where performed in accordance with subsection
(l) of this section for inspection by the agency.
(x) Digital imaging acquisition systems. Users of digital
imaging acquisition systems shall follow quality assurance/quality
control protocol for image processing established by the manufacturer
or, if no manufacturer's protocol is available, by the registrant.
The registrant shall include the protocol, whether established by
the registrant or the manufacturer in its operating and safety procedures.
The registrant shall document the frequency at which the quality assurance/quality
control protocol is performed. Documentation shall include the date
and initials of the individual completing the document and shall be
maintained at the site where performed in accordance with subsection
(l) of this section for inspection by the agency.
(B) Additional requirements for radiation therapy simulators
used in the general radiographic mode of operation.
(i) Beam quality (HVL). The half-value layer of the
useful beam for a given x-ray tube potential shall not be less than
the values shown in the following Table IV. If it is necessary to
determine such half-value layer at an x-ray tube potential that is
not listed in Table IV, linear interpolation may be made.
Attached Graphic
(ii) Technique and exposure indicators.
(I) The technique factors to be used during an exposure
shall be indicated before the exposure begins except when automatic
exposure controls are used, in which case the technique factors that
are set prior to the exposure shall be indicated.
Cont'd... |
