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
radiographic x-ray systems used in relation to the healing arts, except systems
used for dental intra-oral or veterinary radiography.
Section 1. Applicability. This administrative
regulation shall apply to radiographic x-ray systems used in relation to the
healing arts, except dental intra-oral, fluoroscopic, veterinary radiographic,
or computed tomography and to persons, equipment and materials used in
connection with the possession, use or operation of the systems.
Section 2. Permanent Structural Shielding.
Permanent structural shielding and protective barriers shall be used as
necessary to insure that no person other than the patient receives a dose
equivalent in excess of the limits specified in these regulations.
Section 3. Beam Limitation. The useful beam
shall be limited to the area of clinical interest as follows:
(1) General purpose stationary and mobile
x-ray systems.
(a) A means shall be provided
for stepless adjustment of the size of the x-ray field. The minimum field size
at an SID of 100 centimeters shall be equal to or less than five (5) by five
(5) centimeters;
(b) No dimension
of the x-ray field, measured in the plane of the image receptor, shall exceed
the corresponding dimension of the image receptor by more than two (2) percent
of the source to image receptor distance (SID) measured if the plane of the
image receptor is perpendicular to the primary ray of the x-ray field;
and
(c) A method shall be provided
for visually defining the perimeter of the x-ray field. The total misalignment
of the edges of the visually defined field with the respective edges of the
x-ray field along either the length or width of the visually defined field
shall not exceed two (2) percent of the distance from the source to the center
of the visually defined field when the surface upon which it appears is
perpendicular to the axis of the x-ray beam.
(d) The cabinet may grant an exemption as
provided by
902 KAR
100:015 Section 7(1) on non-certified x-ray to the
requirements of paragraphs (a) and (c) of this subsection for equipment
registered prior to the effective date of this administrative
regulation.
(2) In
addition to the requirements of subsection (1) of this section, stationary
general purpose x-ray systems, both certified and noncertified, shall meet the
following requirements:
(a) A method shall be
provided to indicate if the axis of the x-ray beam is perpendicular to the
plane of the image receptor, to align the center of the x-ray field with
respect to the center of the image receptor to within two (2) percent of the
SID and to indicate the SID to within two (2) percent.
(b) The beam limiting device shall indicate
numerically the field size in the plane of the image receptor to which it is
adjusted; and
(c) Indication of
field size dimensions and SID's shall be specified in inches or centimeters, so
that aperture adjustments result in x-ray field dimensions in the plane of the
image receptor which correspond to those indicated by the beam limiting device
to within two (2) percent of the SID if the beam axis is indicated to be
perpendicular to the plane of the image receptor.
(3) Radiographic equipment designed for only
one (1) image receptor size at a fixed SID shall be provided with means to
limit the field at the plane of the image receptor to dimensions no greater
than those of the image receptor, and to align the center of the x-ray field
with the center of the image receptor to within two (2) percent of the SID, or
shall be provided with means to both size and align the x-ray field so that the
x-ray field at the plane of the image receptor does not extend beyond any edge
of the image receptor.
(4)
Radiographic systems designed only for mammography and general purpose
radiographic systems, if special attachments for mammography are in service,
shall be provided with means to limit the useful beam so that the x-ray field
at the plane of the image receptor does not extend beyond any edge of the image
receptor at any designated SID except the edge of the image receptor designed
to be adjacent to the chest wall where the x-ray field may not extend beyond
this edge by more than two (2) percent of the SID. This requirement can be met
with a system which performs as prescribed in subsection (5)(c) of this
section. If the beam-limiting device and image receptor support device are
designed to be used to immobilize the breast during a mammographic procedure
and the SID may vary, the SID indication specified in subsection (5)(c) of this
section shall be the maximum SID for which the beam limiting device or aperture
is designed. In addition, each image receptor support intended for installation
on a system designed only for mammography shall have clear and permanent
markings to indicate the maximum image receptor size for which it is
designed.
(5) For x-ray systems
other than those described in subsections (1), (2), (3), (4) and (5) of this
section:
(a) Means shall be provided to limit
the x-ray field in the plane of the image receptor so that the field does not
exceed each dimension of the image receptor by more than two (2) percent of the
SID if the axis of the x-ray beam is perpendicular to the plane of the image
receptor and align the center of the x-ray field with the center of the image
receptor to within two (2) percent of the SID, or means shall be provided to
both size and align the x-ray field so that the x-ray field at the plane of the
image receptor does not extend beyond any edge of the image receptor;
or
(b) Shall meet the requirements
for a general purpose x-ray system as specified in subsection (1) of this
section; or
(c) If alignment means
are also provided, an assortment of removable, fixed-aperture, beam-limiting
devices sufficient to meet the requirement for each combination of image
receptor size and SID for which the unit is designed with each device having
clear and permanent markings to indicate the image receptor size and SID for
which it is designed or a beam-limiting device having multiple fixed apertures
sufficient to meet the requirement for each combination of image receptor size
and SID for which the unit is designed. Permanent, clearly legible markings
shall indicate the image receptor size and SID for which each aperture is
designed and shall indicate which aperture is in position for use.
Section 4. Field
Limitation and Alignment on General Purpose X-ray Systems.
(1) For stationary, general purpose x-ray
systems which contain a tube housing assembly, an x-ray control, and, for those
systems so equipped, a table, certified in accordance with
21 CFR
1020.30(c), positive beam
limitation shall be provided if the following conditions are met:
(a) The image receptor is inserted into a
permanently mounted cassette holder;
(b) The image receptor length and width are
each less than fifty (50) centimeters;
(c) The x-ray beam axis is within plus or
minus three (3) degrees of vertical and the SID is ninety (90) centimeters to
130 centimeters inclusive or the x-ray beam axis is within plus or minus three
(3) degrees of horizontal and the SID is ninety (90) centimeters to 205
centimeters inclusive;
(d) The
x-ray beam axis is perpendicular to the plane of the image receptor to within
plus or minus three (3) degrees;
(e) Neither tomographic nor stereoscopic
radiography is being performed; and
(f) The positive beam limitation (PBL) system
has not been intentionally overridden in accordance with subsection (3) of this
section.
(2) PBL shall
prevent the production of x-rays if;
(a)
Either the length or width of the x-ray field in the plane of the image
receptor differs, except as permitted by subsection (5) of this section, from
the corresponding image receptor dimensions by more than three (3) percent of
the SID; or
(b) The sum of the
length and width differences as stated in paragraph (a) of this subsection
without regard to sign exceeds four (4) percent of the SID.
(3) If a means of overriding the
PBL system exists, that means:
(a) Shall be
designed for use only in the event of PBL system failure or if the system is
being serviced;
(b) Shall require
that a key be utilized to defeat the PBL, that the key or key remain in place
during the entire time the PBL system is overridden and that the key switch be
clearly and durably labeled "For X-ray Field Limitation System Failure" if the
means of overriding the PBL system is in a position that the operator would
consider it part of the operational controls or if it is referenced in the
operator's manual or in other materials intended for the operator;
and
(c) Shall be used only for that
period of time necessary for the repair or service of the system.
(4) Compliance with subsection (2)
of this section shall be determined if the equipment indicates that the beam
axis is perpendicular to the plane of the image receptor and the provisions of
subsection (1) of this section are met. Compliance shall be determined no
sooner than five (5) seconds after insertion of the image receptor.
(5) The positive beam limitation system shall
be capable of operation, at the discretion of the operator, so that the size of
the field may be made smaller than the size of the image receptor through
stepless adjustment of the field size. The minimum field size at an SID of 100
centimeters shall be equal to or less than five (5) by five (5)
centimeters.
(6) The PBL system
shall be designed so that if a change in image receptor does not cause an
automatic return to PBL function as described in subsection (2) of this
section, then any change of image receptor size or SID shall cause the
automatic return.
Section
5. X-ray Control (Exposure Switch).
(1) A control shall be incorporated into each
x-ray system so such that an exposure can be terminated instantly except for
exposures of one-half (1/2) second or less, or during serial radiography a
means shall be provided to permit completion of a single exposure of the series
in process.
(2) The location of
x-ray exposure controls on stationary x-ray systems shall be regulated as
follows:
(a) Stationary x-ray systems shall be
required to have the x-ray control permanently mounted in a protected area so
that the operator is required to remain in that protected area during the
entire exposure; and
(b) The
exposure controls shall be behind a window of lead equivalent glass equal to
that required by the adjacent barrier or an appropriate viewing system shall be
provided so that the operator can see the patient without having to leave the
protected area during the exposure.
(3) Mobile and portable x-ray systems which
are used for one (1) week or more in one (1) location (one (1) room or suite),
shall be considered stationary for the purposes of this administrative
regulation and these systems shall meet the requirements of subsection (2) of
this section.
(4) Mobile and
portable x-ray systems which are used for greater than one (1) hour and less
than one (1) week in one (1) location (one (1) room or suite) shall meet the
requirement of subsection (3) of this section or be provided with a protective
barrier one and nine-tenths (1.9) meters in height having a window of lead
equivalent glass equal to that required of the barrier and placed at least one
and eight-tenths (1.8) meters from the tube housing assembly and at least one
and eight- tenths (1.8) meters from the patient.
(5) Mobile and portable x-ray systems which
are used for one (1) hour or less in one (1) location (one (1) room or suite)
shall meet the requirement of subsection (3) or (4) of this Section or be
provided with a method of x-ray control that permits the operator to be at
least three and six-tenths (3.6) meters from the tube housing assembly during
an exposure.
Section 6.
Automatic Exposure Controls (Phototimers). If an automatic exposure control is
utilized, the following requirements shall be met:
(1) An indicator shall be provided on the
control panel to indicate if this mode of operation is selected;
(2) If the x-ray tube potential is equal to
or greater than fifty (50) kVp, the minimum exposure time for field emission
equipment rated for pulsed operation shall be equal to or less than a time
interval equivalent to two (2) pulses;
(3) The minimum exposure time for equipment
other than that specified in subsection (2) of this section shall be equal to
or less than one-sixtieth (1/60) second or a time interval required to deliver
five (5) mAs, whichever is greater;
(4) The product of peak x-ray tube potential,
current, and exposure time shall be limited to not more than sixty (60) kWs per
exposure or the product of x-ray tube current and exposure time shall be
limited to not more than 600 mAs per exposure except if the x-ray tube
potential is less than fifty (50) kVp in which case the product of x-ray tube
current and exposure time shall be limited to not more than 2000 mAs per
exposure; and
(5) A visible signal
shall indicate that an exposure has been terminated at the limits described in
subsection (4) of this section, and manual resetting shall be required before
further automatic time exposures can be made.
Section 7. Source to Skin or Image Receptor
Distance.
(1) All mobile or portable
radiographic x-ray systems shall be provided with a durable, securely-fastened
means to limit the source to skin distance to not less than thirty (30)
centimeters.
(2) Radiographic x-ray
systems shall be equipped with a device or reference, other than a collimator
light localizer, which shall indicate reference, or measure the selected source
to receptor distance to within two and five-tenths (2.5) centimeters.
Section 8. Standby Radiation from
Capacitor Energy Storage Equipment. Radiation emitted from the x-ray tube if
the exposure switch or timer is not activated shall not exceed a rate of two
(2) milliroentgens per hour at five (5) centimeters from an accessible surface
of the diagnostic source assembly, with the beam-limiting device fully
open.
Section 9. Personnel
Monitoring. Personnel monitoring shall be required for individuals operating
portable or mobile x-ray systems.
Section
10. Linearity. On x-ray systems certified under the federal
performance standard, if the equipment allows a choice of x-ray tube current
settings and is operated on a power supply as specified by the manufacturer in
accordance with the requirements of applicable federal standards, for a fixed
x-ray tube potential within the range of forty (40) to 100 percent of the
maximum rating, the average ratios of exposure to the indicated
milliampere-seconds product obtained at two (2) consecutive tube current
settings shall not differ by more than one-tenth (0.1) times their sum
X1 - X2 < 0.10
(X1 + X2).
STATUTORY AUTHORITY:
KRS 194.050,
211.090,
211.844