Texas Register, Volume 32, Number 23, Pages 3077-3422, June 8, 2007 Page: 3,160
This periodical is part of the collection entitled: Texas Register and was provided to The Portal to Texas History by the UNT Libraries Government Documents Department.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
(iii) following any repair of the teletherapy unit that
includes removal of the sealed source or major repair of the components
associated with the sealed source exposure assembly; and
(C) at intervals not to exceed one year.
(2) Full calibration measurements shall include determina-
tion of the following:
(A) the output within plus or minus 3.0% for the range
of field sizes and for the distance or range of distances used for medical
use;
(B) the coincidence of the radiation field and the field
indicated by the light beam localizing device;
(C) uniformity of the radiation field and its dependence
on the orientation of the useful beam;
(D) timer accuracy and linearity over the range of use;
(E) "on-off" error; and
(F) the accuracy of all distance measuring and localiza-
tion devices in medical use.
(3) The licensee shall use the dosimetry system described
in subsection (iii)(1) of this section to measure the output for one set of
exposure conditions. The remaining radiation measurements required
in paragraph (2)(A) of this subsection may be made using a dosimetry
system that indicates relative dose rates.
(4) The licensee shall make full calibration measurements
required by paragraph (1) of this subsection in accordance with pub-
lished protocols accepted by nationally recognized bodies.
(5) The licensee shall mathematically correct the outputs
determined in paragraph (2)(A) of this subsection for physical decay at
intervals not to exceed one month for cobalt-60, six months for cesium-
137, or at intervals consistent with 1.0% decay for all other nuclides.
(6) Full calibration measurements required by paragraph
(1) of this subsection and physical decay corrections required by para-
graph (5) of this subsection shall be performed by an authorized med-
ical physicist.
(7) The licensee shall retain a record of each calibration in
accordance with subsection (www) of this section for inspection by the
agency. The record shall include the following:
(A) date of the calibration;
(B) manufacturer's name, model number and serial
number of the teletherapy unit's sealed source and the instruments
used to calibrate the unit;
(C) results and an assessment of the full calibrations;
and
(D) signature of the authorized medical physicist who
performed the full calibration.
(kkk) Full calibration measurements on remote afterloader
units.
(1) A licensee authorized to use a remote afterloader for
medical use shall perform full calibration measurements on each unit
as follows:
(A) before the first medical use of the unit;
(B) before medical use under any of the following con-
ditions:
(i) following replacement of the sealed source;(ii) following reinstallation of the unit in a new lo-
cation outside the facility;
(iii) following any repair of the unit that includes re-
moval of the sealed source or major repair of the components associated
with the sealed source exposure assembly;
(C) at intervals not to exceed three months for high
dose-rate, medium dose-rate, and pulsed dose-rate remote afterloader
units with sealed sources whose half-life exceeds 75 days; and
(D) at intervals not to exceed one year for low dose-rate
afterloader units.
(2) Full calibration measurements shall include, as appli-
cable, determination of the following:
(A) the output within plus or minus 5.0%;
(B) sealed source positioning accuracy to within plus or
minus millimeter (mm);
(C) sealed source retraction with backup battery upon
power failure;
(D) length of the sealed source transfer tubes;
(E) timer accuracy and linearity over the typical range
of use;
(F) length of the applicators; and
(G) function of the sealed source transfer tubes, appli-
cators, and transfer tube-applicator interfaces.
(3) A licensee shall use the dosimetry system described in
subsection (iii)(1) of this section to measure the output.
(4) A licensee shall make full calibration measurements re-
quired by paragraph (1) of this subsection in accordance with published
protocols accepted by nationally recognized bodies.
(5) In addition to the requirements for full calibrations for
low dose-rate remote afterloader units in paragraph (2) of this subsec-
tion, a licensee shall perform an autoradiograph of the sealed source(s)
to verify inventory and sealed source(s) arrangement at intervals not to
exceed three months.
(6) For low dose-rate remote afterloader units, a licensee
may use measurements provided by the sealed source manufacturer that
are made in accordance with paragraphs (1) - (5) of this subsection.
(7) The licensee shall mathematically correct the outputs
determined in paragraph (2)(A) of this subsection for physical decay at
intervals consistent with 1.0% physical decay.
(8) Full calibration measurements required by paragraph
(1) of this subsection and physical decay corrections required by para-
graph (7) of this subsection shall be performed by an authorized med-
ical physicist.
(9) The licensee shall retain a record of each calibration in
accordance with subsection (www) of this section for inspection by the
agency. The record shall include the following:
(A) date of the calibration;
(B) manufacturer's name, model number and serial
number of the remote afterloader unit's sealed source, and the instru-
ments used to calibrate the unit;
(C) results and an assessment of the full calibrations;
(D) signature of the authorized medical physicist of this
section; and32 TexReg 3160 June 8, 2007 Texas Register
Upcoming Pages
Here’s what’s next.
Search Inside
This issue can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Periodical.
Texas. Secretary of State. Texas Register, Volume 32, Number 23, Pages 3077-3422, June 8, 2007, periodical, June 8, 2007; Austin, Texas. (https://texashistory.unt.edu/ark:/67531/metapth97400/m1/83/?rotate=270: accessed July 16, 2024), University of North Texas Libraries, The Portal to Texas History, https://texashistory.unt.edu.; crediting UNT Libraries Government Documents Department.