Current through Register Vol. 51, No. 3, September 1, 2024
RELATES TO: KRS 211.842-211.852,
211.990(4)
NECESSITY, FUNCTION, AND CONFORMITY: The Cabinet for Human
Resources is authorized by
KRS
211.844 to provide by administrative
regulation for the registration and licensing of the possession or use of
sources of ionizing or electronic product radiation and the handling and
disposal of radioactive waste. The purpose of this administrative regulation is
to provide special requirements for the possession, use, and operation of
fluoroscopic x-ray systems in the healing arts.
Section 1. Applicability. This regulation
shall apply to fluoroscopic x-ray systems and to persons, equipment and
materials used in connection with the possession and use or operation of these
such systems.
Section 2. Equipment.
Fluoroscopic x-ray systems shall meet the following requirements:
(1) The tube housing assembly shall be of the
diagnostic type;
(2) Cones or
shutters used to restrict the size of the useful beam shall provide the same
degree of attenuation as required of the tube housing; and
(3) Fluoroscopic imaging devices used for
optical viewing which are not mechanically linked to the x-ray tube shall not
be utilized.
Section 3.
Protective Barrier and Field Size.
(1) The
fluoroscopic tube shall not be capable of producing x-rays unless the primary
protective barrier is in position to intercept the entire useful
beam.
(2) The entire cross-section
of the useful beam shall be intercepted by the primary protective barrier of
the fluoroscopic image assembly at every SID (e.g., source to image receptor
distance).
Section 4.
Limitation to the Imaging Surface. The x-ray field shall be restricted so that
the following requirements are met:
(1) On
nonimage-intensified fluoroscopic x-ray systems, the x-ray field shall not
extend beyond the entire visible area of the image receptor. This requirement
applies to field size during both fluoroscopic procedures and spot filming
procedures. In addition:
(a) Means shall be
provided for stepless adjustment of the field size;
(b) The minimum field size at the greatest
SID shall be equal to or less than five (5) by five (5) centimeters;
(c) Equipment manufactured after February 25,
1978, if the angle between the image receptor and the beam axis of the x-ray
beam is variable, shall be provided with the means to indicate if the axis of
the x-ray beam is perpendicular to the plane of the image receptor;
and
(d) Compliance with this
subsection shall be determined with the beam axis indicated to be perpendicular
to the plane of the image receptor.
(2) On image-intensified fluoroscopic systems
with manual shutter controls, the x-ray beam shall not exceed the area of the
largest image receptor, if measured with the fluoroscopic image assembly
positioned thirty-five and five-tenths (35.5) centimeters from the table top or
panel surface, and with the manual shutter controls opened to the fullest
extent. Collimators located between the image receptor and patients shall not
be used to fulfill this requirement. Means shall be provided to reduce the
x-ray field size to five (5) by five (5) centimeters or less at the maximum
SID; or
(3) For image-intensified
fluoroscopic equipment, neither the length nor width of the x-ray field in the
plane of the image receptor shall exceed that of the visible area of the image
receptor by more than three (3) percent of the SID. The sum of the excess
length and width shall be no greater than four (4) percent of the SID.
(a) For rectangular x-ray fields used with
circular image receptors, the error in alignment shall be determined along the
length and width dimensions of the x-ray field which pass through the center of
the visible area of the image receptor.
(b) Means shall be provided to permit further
limitation of the field. Beam-limiting devices manufactured after May 22, 1979,
and incorporated in equipment with a variable SID or a visible area of greater
than 300 square centimeters shall be provided with means for stepless
adjustment of the x-ray field. Equipment with a fixed SID and a visible area of
300 square centimeters or less shall be provided with stepless adjustment of
the x-ray field or with means to further limit the x-ray field size at the
plane of the image receptor to 125 square centimeters or less. Stepless
adjustment shall, at the greatest SID, provide continuous field sizes from the
maximum obtainable to a field size of five (5) by five (5) centimeters or
less.
(c) For equipment
manufactured after February 25, 1978, if the angle between the image receptor
and beam axis is variable, means shall be provided to indicate if the axis of
the x-ray beam is perpendicular to the plane of the image receptor.
(4) Spot film devices which are
certified components shall meet the following additional requirements:
(a) Means shall be provided between the
source and the patient for adjustment of the x-ray field size in the plane of
the film to the size of the portion of the film which has been selected on the
spot film selector. This adjustment shall be automatically accomplished except
if the x-ray field size in the plane of the film is smaller than that of the
selected portion of the film. For spot film devices manufactured after June 21,
1979, if the x-ray field size is less than the size of the selected portion of
the film, the means for adjustment of the field size shall be only at the
operator's option;
(b) It shall be
possible to adjust the x-ray field size in the plane of the film to a size
smaller than the selected portion of the film. The minimum field size at the
greatest SID shall be equal to, or less than, five (5) by five (5)
centimeters;
(c) The center of the
x-ray field in the plane of the film shall be aligned with the center of the
selected portion of the film to within two (2) percent of the SID;
and
(d) On spot film devices
manufactured after February 25, 1978, if the angle between the plane of the
image receptor and beam axis is variable, means shall be provided to indicate
if the axis of the x-ray beam is perpendicular to the plane of the image
receptor, and compliance shall be determined with the beam axis indicated to be
perpendicular to the plane of the image receptor.
(5) If a means exists to override the
automatic x-ray field size adjustments required in this section, that means:
(a) Shall be designed for use only if the
system fails:
(b) Shall incorporate
a signal visible at the fluoroscopist's position which shall indicate if the
automatic field size adjustment is overridden; and
(c) Shall be clearly and durably labeled as
follows:
"FOR X-RAY FIELD LIMITATION SYSTEM FAILURE".
Section 5. Activation
of the Fluoroscopic Tube. X-ray production in the fluoroscopic mode shall be
controlled by a device which requires continuous pressure by the fluoroscopist
for the entire time of an exposure. If recording serial fluoroscopic images,
the fluoroscopist shall be able to terminate the x-ray exposures, but means may
be provided to permit completion of a single exposure of the series in
process.
Section 6. Exposure Rate
Limits. The entrance exposure rate allowable limits and requirements are as
follows:
(1) The exposure rate at the point
where the center of the useful beam enters the patient shall not exceed ten
(10) roentgens per minute, except during recording of fluoroscopic images or if
provided with optional high level control;
(2) If provided with optional high level
control, the equipment shall not be operable at a combination of tube potential
and current which results in an exposure rate in excess of five (5) roentgens
per minute at the point where the center of the useful beam enters the patient
unless the high level control is activated.
(a) Special means of activation of high level
controls shall be required. The high level control shall only be operable if
continuous manual activation is provided by the operator.
(b) A continuous signal audible to the
fluoroscopist shall indicate that the high level control is being
employed.
(3) Certified
systems which do not incorporate an automatic exposure control shall not be
operable at a combination of tube potential and current which results in an
exposure rate in excess of five (5) roentgens per minute at the point where the
center of beam enters the patient except during recording of fluoroscopic
images or if provided with an optional high level control;
(4) Compliance with the entrance exposure
rate limits shall be determined as follows:
(a) Movable grids and compression devices
shall be removed from the useful beam during the measurement;
(b) If the source is below the table,
exposure rate shall be measured one (1) centimeter above the tabletop or
cradle;
(c) If the source is above
the table, the exposure rate shall be measured at thirty (30) centimeters above
the tabletop with the end of the beam limiting device or spacers positioned as
closely as possible to the point of measurement;
(d) C-arm fluoroscopes, both stationary and
mobile, shall meet the entrance exposure rate limits in subsections (1), (2)
and (3) of this section thirty (30) centimeters from the input surface of the
fluoroscope imaging assembly with the source positioned at an available SID if
the end of the spacer assembly or beam-limiting device is not closer than
thirty (3) centimeters from the input surface of the fluoroscopic imaging
assembly.
(5) Periodic
measurements of the exposure rate shall be made. An adequate period for these
measurements shall be annually or after maintenance of the system which might
affect the exposure rate;
(a) Results of these
measurements shall be posted where a fluoroscopist has ready access to them
while using that fluoroscopic x-ray system and in the records required by these
administrative regulations. Results of the measurements shall include the
exposure rate in roentgens per minute, as well as the physical factors used to
determine the data, the name of the person who performed the measurements, and
the date the measurements were performed;
(b) Conditions of periodic measurement of
entrance exposure rate are as follows:
1. The
kVp shall be the kVp typical of clinical use of the x-ray system;
2. The measurement shall be made under the
conditions of subsection (4) of this section;
3. Fluoroscopic x-ray system(s) that
incorporate automatic exposure control (e.g., automatic brightness control)
shall have sufficient material placed in the useful beam to produce a
milliamperage typical of the use of the fluoroscopic x-ray system;
and
4. Fluoroscopic x-ray system(s)
that do not incorporate automatic exposure control shall utilize a
milliamperage typical of the clinical use of the fluoroscopic x-ray system.
Materials (e.g., an attenuation block) shall be placed in the useful beam to
protect the imaging system.
Section 7. Radiation Rate Limits Transmitted
Through the Primary Barrier. The exposure rate due to transmission through the
primary protective barrier with the attenuation block in the useful beam,
combined with radiation from the image intensifier, if provided, shall not
exceed two (2) milliroentgens per hour at ten (10) centimeters from accessible
surfaces of the fluoroscopic imaging assembly beyond the plane of the image
receptor for each roentgen per minute of entrance exposure rate. The
transmitted exposure rate shall be measured so that the following requirements
are met:
(1) The exposure rate due to
transmission through the primary protective barrier combined with radiation
from the image intensifier shall be determined by measurements averaged over an
area of 100 square centimeters with no linear dimension greater than twenty
(20) centimeters;
(2) If the x-ray
source is below the table top, the measurement shall be made with the input
surface of the fluoroscopic imaging assembly positioned thirty (30) centimeters
above the table top;
(3) If the
x-ray source is above the table top and the SID is variable, the measurement
shall be made with the end of the beam limiting device or spacer as close to
the table top as it can be placed, except that it shall not be closer than
thirty (30) centimeters;
(4)
Movable grids and compression devices shall be removed from the useful beam
during the measurement; and
(5) The
attenuation block shall be positioned in the useful beam ten (10) centimeters
from the point of measurement of the entrance exposure rate and between this
point and the input surface of the fluoroscopic imaging assembly.
Section 8. Indication of Tube
Potential and Current. During fluoroscopy and cinefluorography, x-ray tube
potential and current shall be continuously indicated on the control panel or
within view of the fluoroscopist.
Section
9. Source to Skin Distance. The source to skin distance shall not
be less than:
(1) Thirty-eight (38)
centimeters on stationary fluoroscopes certified under the federal performance
standard;
(2) Thirty-five and
five-tenths (35.5) centimeters on stationary fluoroscopes which are not
certified under the federal performance standard;
(3) Thirty (30) centimeters on mobile
fluoroscopic x-ray systems; or
(4)
Twenty (20) centimeters for image-intensified fluoroscopes used for specific
surgical applications. The written safety procedures shall provide
precautionary measures to be adhered to during the use of this
device.
Section 10.
Fluoroscopic Timer. A means shall be provided to preset the cumulative on-time
of the fluoroscopic x-ray system. The fluoroscopic x-ray system shall not be
able to be activated without this timer also being activated. The end of the
predetermined period of irradiation shall be indicated by an audible signal.
The audible signal shall continue until the timing device is reset. The maximum
cumulative time of the timing device shall not exceed five (5) minutes without
resetting.
Section 11. Mobile
Fluoroscopes. Mobile fluoroscopic systems shall be provided with image
intensification. It shall be impossible to operate mobile fluoroscopic systems
unless the useful beam is intercepted by the image intensifier.
Section 12. Control of Scattered Radiation.
(1) Fluoroscopic table designs combined with
procedures utilized shall expose no unprotected part of staff or an ancillary
person's body to unattenuated scattered radiation which originates from under
the table. The attenuation required shall not be less than 0.25 mm lead
equivalent; and
(2) Equipment
configuration design combined with procedures shall expose no portion of staff
or an ancillary person's body, except the extremities, to the unattenuated
scattered radiation emanating from above the tabletop unless that individual:
(a) Is at least 120 cm from the center of the
useful beam, or
(b) The radiation
has passed through not less than 0.25 mm lead equivalent material (e.g., leaded
drapes, Bucky slot cover panel, or self supporting leaded curtains) in addition
to lead equivalency provided by protective aprons.
(3) Exceptions to subsection (2)(a) and (b)
of this section may be made in some special procedures if a sterile field does
not permit the use of the normal protective barriers. If the use of prefitted
sterilized covers for the barriers is practical, the cabinet shall not permit
an exception.
Section
13. Operating Procedures and Auxiliary Equipment. The following
operating procedures and auxiliary equipment shall be utilized, if applicable,
in the operation of a fluoroscopic x-ray system:
(1) Fluoroscopy performed by technologists
shall be under the direction of a radiologist and be exclusively for
localization purposes;
(2) Spot
film images shall be obtained only by a licensed practitioner of the healing
arts;
(3) Protective gloves of at
least 0.25 mm lead equivalent shall be readily available to the fluoroscopist
during every examination;
(4) The
eyes of the fluoroscopist shall be adequately dark-adapted before using
nonimageintensified fluoroscopic x-ray systems;
(5) Extraneous light that interferes with the
fluoroscopic examination shall be eliminated;
(6) Hand-held fluoroscopic screens shall not
be used;
(7) Protective aprons of
at least 0.25 mm lead equivalence shall be worn by the fluoroscopist and by
persons in the fluoroscopic room except the patient during each
examination;
(8) Fluoroscopic x-ray
systems designed strictly for fluoroscopy shall not be used for spot filming or
radiography; and
(9) Dental
fluoroscopic x-ray systems without image intensification shall not be
used.
Section 14.
Radiation Therapy Simulation Systems. Radiation therapy simulation systems
shall be exempt from the requirements of Sections 4, 6, and 10 of this
administrative regulation if:
(1) Systems are
designed and used in a manner that no individual other than the patient is in
the x-ray room if the system is producing x-rays; and
(2) Systems which do not meet the
requirements of Section 10 of this administrative regulation are provided with
a means of indicating the cumulative time that an individual patient has been
exposed to x-rays. Procedures shall require in these cases that the timer be
reset between examinations.
STATUTORY AUTHORITY:
KRS 194.050,
211.090,
211.844
