[Code of Federal Regulations]
[Title 21, Volume 8]
[Revised as of April 1, 2008]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR1020.30]
[Page 623-635]
TITLE 21--FOOD AND DRUGS
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN
SERVICES (CONTINUED)
PART 1020_PERFORMANCE STANDARDS FOR IONIZING RADIATION EMITTING
PRODUCTS--Table of Contents
Sec. 1020.30 Diagnostic x-ray systems and their major components.
(a) Applicability. (1) The provisions of this section are applicable
to:
(i) The following components of diagnostic x-ray systems:
(A) Tube housing assemblies, x-ray controls, x-ray high-voltage
generators, x-ray tables, cradles, film changers, vertical cassette
holders mounted in a fixed location and cassette holders with front
panels, and beam-limiting devices manufactured after August 1, 1974.
(B) Fluoroscopic imaging assemblies manufactured after August 1,
1974, and before April 26, 1977, or after June 10, 2006.
(C) Spot-film devices and image intensifiers manufactured after
April 26, 1977.
(D) Cephalometric devices manufactured after February 25, 1978.
(E) Image receptor support devices for mammographic x-ray systems
manufactured after September 5, 1978.
(F) Image receptors that are electrically powered or connected with
the x-ray system manufactured on or after June 10, 2006.
(G) Fluoroscopic air kerma display devices manufactured on or after
June 10, 2006.
(ii) Diagnostic x-ray systems, except computed tomography x-ray
systems, incorporating one or more of such components; however, such x-
ray systems shall be required to comply only with those provisions of
this section and Sec. Sec. 1020.31 and 1020.32, which relate to the
components certified in accordance with paragraph (c) of this section
and installed into the systems.
(iii) Computed tomography (CT) x-ray systems manufactured before
November 29, 1984.
(iv) CT gantries manufactured after September 3, 1985.
(2) The following provisions of this section and Sec. 1020.33 are
applicable to CT x-ray systems manufactured or remanufactured on or
after November 29, 1984:
(i) Section 1020.30(a);
(ii) Section 1020.30(b) ``Technique factors'';
(iii) Section 1020.30(b) ``CT,'' ``Dose,'' ``Scan,'' ``Scan time,''
and ``Tomogram'';
(iv) Section 1020.30(h)(3)(vi) through (h)(3)(viii);
(v) Section 1020.30(n);
(vi) Section 1020.33(a) and (b);
[[Page 624]]
(vii) Section 1020.33(c)(1) as it affects Sec. 1020.33(c)(2); and
(viii) Section 1020.33(c)(2).
(3) The provisions of this section and Sec. 1020.33 in its
entirety, including those provisions in paragraph (a)(2) of this
section, are applicable to CT x-ray systems manufactured or
remanufactured on or after September 3, 1985. The date of manufacture of
the CT system is the date of manufacture of the CT gantry.
(b) Definitions. As used in this section and Sec. Sec. 1020.31,
1020.32, and 1020.33, the following definitions apply:
Accessible surface means the external surface of the enclosure or
housing provided by the manufacturer.
Accessory component means:
(1) A component used with diagnostic x-ray systems, such as a cradle
or film changer, that is not necessary for the compliance of the system
with applicable provisions of this subchapter but which requires an
initial determination of compatibility with the system; or
(2) A component necessary for compliance of the system with
applicable provisions of this subchapter but which may be interchanged
with similar compatible components without affecting the system's
compliance, such as one of a set of interchangeable beam-limiting
devices; or
(3) A component compatible with all x-ray systems with which it may
be used and that does not require compatibility or installation
instructions, such as a tabletop cassette holder.
Air kerma means kerma in air (see definition of Kerma).
Air kerma rate (AKR) means the air kerma per unit time.
Aluminum equivalent means the thickness of aluminum (type 1100
alloy)\1\ affording the same attenuation, under specified conditions, as
the material in question.
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\1\ The nominal chemical composition of type 1100 aluminum alloy is
99.00 percent minimum aluminum, 0.12 percent copper, as given in
``Aluminum Standards and Data'' (1969). Copies may be obtained from The
Aluminum Association, New York, NY.
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Articulated joint means a joint between two separate sections of a
tabletop which joint provides the capacity for one of the sections to
pivot on the line segment along which the sections join.
Assembler means any person engaged in the business of assembling,
replacing, or installing one or more components into a diagnostic x-ray
system or subsystem. The term includes the owner of an x-ray system or
his or her employee or agent who assembles components into an x-ray
system that is subsequently used to provide professional or commercial
services.
Attenuation block means a block or stack of type 1100 aluminum
alloy, or aluminum alloy having equivalent attenuation, with dimensions
20 centimeters (cm) or larger by 20 cm or larger by 3.8 cm, that is
large enough to intercept the entire x-ray beam.
Automatic exposure control (AEC) means a device which automatically
controls one or more technique factors in order to obtain at a
preselected location(s) a required quantity of radiation.
Automatic exposure rate control (AERC) means a device which
automatically controls one or more technique factors in order to obtain
at a preselected location(s) a required quantity of radiation per unit
time.
Beam axis means a line from the source through the centers of the x-
ray fields.
Beam-limiting device means a device which provides a means to
restrict the dimensions of the x-ray field.
C-arm fluoroscope means a fluoroscopic x-ray system in which the
image receptor and the x-ray tube housing assembly are connected or
coordinated to maintain a spatial relationship. Such a system allows a
change in the direction of the beam axis with respect to the patient
without moving the patient.
Cantilevered tabletop means a tabletop designed such that the
unsupported portion can be extended at least 100 cm beyond the support.
Cassette holder means a device, other than a spot-film device, that
supports and/or fixes the position of an x-ray film cassette during an
x-ray exposure.
Cephalometric device means a device intended for the radiographic
visualization and measurement of the dimensions of the human head.
Coefficient of variation means the ratio of the standard deviation
to the
[[Page 625]]
mean value of a population of observations. It is estimated using the
following equation:
[GRAPHIC] [TIFF OMITTED] TR10JN05.001
where:
s = Estimated standard deviation of the population.
X = Mean value of observations in sample.
Xi = ith observation sampled.
n = Number of observations sampled.
Computed tomography (CT) means the production of a tomogram by the
acquisition and computer processing of x-ray transmission data.
Control panel means that part of the x-ray control upon which are
mounted the switches, knobs, pushbuttons, and other hardware necessary
for manually setting the technique factors.
Cooling curve means the graphical relationship between heat units
stored and cooling time.
Cradle means:
(1) A removable device which supports and may restrain a patient
above an x-ray table; or
(2) A device;
(i) Whose patient support structure is interposed between the
patient and the image receptor during normal use;
(ii) Which is equipped with means for patient restraint; and
(iii) Which is capable of rotation about its long (longitudinal)
axis.
CT gantry means tube housing assemblies, beam-limiting devices,
detectors, and the supporting structures, frames, and covers which hold
and/or enclose these components.
Cumulative air kerma means the total air kerma accrued from the
beginning of an examination or procedure and includes all contributions
from fluoroscopic and radiographic irradiation.
Diagnostic source assembly means the tube housing assembly with a
beam-limiting device attached.
Diagnostic x-ray system means an x-ray system designed for
irradiation of any part of the human body for the purpose of diagnosis
or visualization.
Dose means the absorbed dose as defined by the International
Commission on Radiation Units and Measurements. The absorbed dose, D, is
the quotient of de by dm, where de is the mean energy imparted to matter
of mass dm; thus D=de/dm, in units of J/kg, where the special name for
the unit of absorbed dose is gray (Gy).
Equipment means x-ray equipment.
Exposure (X) means the quotient of dQ by dm where dQ is the absolute
value of the total charge of the ions of one sign produced in air when
all the electrons and positrons liberated or created by photons in air
of mass dm are completely stopped in air; thus X=dQ/dm, in units of C/
kg. A second meaning of exposure is the process or condition during
which the x-ray tube produces x-ray radiation.
Field emission equipment means equipment which uses an x-ray tube in
which electron emission from the cathode is due solely to action of an
electric field.
Fluoroscopic air kerma display device means a device, subsystem, or
component that provides the display of AKR and cumulative air kerma
required by Sec. 1020.32(k). It includes radiation detectors, if any,
electronic and computer components, associated software, and data
displays.
Fluoroscopic imaging assembly means a subsystem in which x-ray
photons produce a set of fluoroscopic images or radiographic images
recorded from the fluoroscopic image receptor. It includes the image
receptor(s), electrical
[[Page 626]]
interlocks, if any, and structural material providing linkage between
the image receptor and diagnostic source assembly.
Fluoroscopic irradiation time means the cumulative duration during
an examination or procedure of operator-applied continuous pressure to
the device, enabling x-ray tube activation in any fluoroscopic mode of
operation.
Fluoroscopy means a technique for generating x-ray images and
presenting them simultaneously and continuously as visible images. This
term has the same meaning as the term ``radioscopy'' in the standards of
the International Electrotechnical Commission.
General purpose radiographic x-ray system means any radiographic x-
ray system which, by design, is not limited to radiographic examination
of specific anatomical regions.
Half-value layer (HVL) means the thickness of specified material
which attenuates the beam of radiation to an extent such that the AKR is
reduced to one-half of its original value. In this definition the
contribution of all scattered radiation, other than any which might be
present initially in the beam concerned, is deemed to be excluded.
Image intensifier means a device, installed in its housing, which
instantaneously converts an x-ray pattern into a corresponding light
image of higher energy density.
Image receptor means any device, such as a fluorescent screen,
radiographic film, x-ray image intensifier tube, solid-state detector,
or gaseous detector, which transforms incident x-ray photons either into
a visible image or into another form which can be made into a visible
image by further transformations. In those cases where means are
provided to preselect a portion of the image receptor, the term ``image
receptor'' shall mean the preselected portion of the device.
Image receptor support device means, for mammography x-ray systems,
that part of the system designed to support the image receptor during a
mammographic examination and to provide a primary protective barrier.
Isocenter means the center of the smallest sphere through which the
beam axis passes when the equipment moves through a full range of
rotations about its common center.
Kerma means the quantity as defined by the International Commission
on Radiation Units and Measurements. The kerma, K, is the quotient of
dEtr by dm, where dEtr is the sum of the initial
kinetic energies of all the charged particles liberated by uncharged
particles in a mass dm of material; thus K=dEtr/dm, in units
of J/kg, where the special name for the unit of kerma is gray (Gy). When
the material is air, the quantity is referred to as ``air kerma.''
Last-image-hold (LIH) radiograph means an image obtained either by
retaining one or more fluoroscopic images, which may be temporally
integrated, at the end of a fluoroscopic exposure or by initiating a
separate and distinct radiographic exposure automatically and
immediately in conjunction with termination of the fluoroscopic
exposure.
Lateral fluoroscope means the x-ray tube and image receptor
combination in a biplane system dedicated to the lateral projection. It
consists of the lateral x-ray tube housing assembly and the lateral
image receptor that are fixed in position relative to the table with the
x-ray beam axis parallel to the plane of the table.
Leakage radiation means radiation emanating from the diagnostic
source assembly except for:
(1) The useful beam; and
(2) Radiation produced when the exposure switch or timer is not
activated.
Leakage technique factors means the technique factors associated
with the diagnostic source assembly which are used in measuring leakage
radiation. They are defined as follows:
(1) For diagnostic source assemblies intended for capacitor energy
storage equipment, the maximum-rated peak tube potential and the
maximum-rated number of exposures in an hour for operation at the
maximum-rated peak tube potential with the quantity of charge per
exposure being 10 millicoulombs (or 10 mAs) or the minimum obtainable
from the unit, whichever is larger;
(2) For diagnostic source assemblies intended for field emission
equipment rated for pulsed operation, the maximum-rated peak tube
potential and
[[Page 627]]
the maximum-rated number of x-ray pulses in an hour for operation at the
maximum-rated peak tube potential; and
(3) For all other diagnostic source assemblies, the maximum-rated
peak tube potential and the maximum-rated continuous tube current for
the maximum-rated peak tube potential.
Light field means that area of the intersection of the light beam
from the beam-limiting device and one of the set of planes parallel to
and including the plane of the image receptor, whose perimeter is the
locus of points at which the illuminance is one-fourth of the maximum in
the intersection.
Line-voltage regulation means the difference between the no-load and
the load line potentials expressed as a percent of the load line
potential; that is,
Percent line-voltage regulation = 100(Vn - Vi)/
Vi
where:
Vn = No-load line potential and
Vi = Load line potential.
Maximum line current means the root mean square current in the
supply line of an x-ray machine operating at its maximum rating.
Mode of operation means, for fluoroscopic systems, a distinct method
of fluoroscopy or radiography provided by the manufacturer and selected
with a set of several technique factors or other control settings
uniquely associated with the mode. The set of distinct technique factors
and control settings for the mode may be selected by the operation of a
single control. Examples of distinct modes of operation include normal
fluoroscopy (analog or digital), high-level control fluoroscopy,
cineradiography (analog or digital), digital subtraction angiography,
electronic radiography using the fluoroscopic image receptor, and
photospot recording. In a specific mode of operation, certain system
variables affecting air kerma, AKR, or image quality, such as image
magnification, x-ray field size, pulse rate, pulse duration, number of
pulses, source-image receptor distance (SID), or optical aperture, may
be adjustable or may vary; their variation per se does not comprise a
mode of operation different from the one that has been selected.
Movable tabletop means a tabletop which, when assembled for use, is
capable of movement with respect to its supporting structure within the
plane of the tabletop.
Non-image-intensified fluoroscopy means fluoroscopy using only a
fluorescent screen.
Peak tube potential means the maximum value of the potential
difference across the x-ray tube during an exposure.
Primary protective barrier means the material, excluding filters,
placed in the useful beam to reduce the radiation exposure for
protection purposes.
Pulsed mode means operation of the x-ray system such that the x-ray
tube current is pulsed by the x-ray control to produce one or more
exposure intervals of duration less than one-half second.
Quick change x-ray tube means an x-ray tube designed for use in its
associated tube housing such that:
(1) The tube cannot be inserted in its housing in a manner that
would result in noncompliance of the system with the requirements of
paragraphs (k) and (m) of this section;
(2) The focal spot position will not cause noncompliance with the
provisions of this section or Sec. 1020.31 or 1020.32;
(3) The shielding within the tube housing cannot be displaced; and
(4) Any removal and subsequent replacement of a beam-limiting device
during reloading of the tube in the tube housing will not result in
noncompliance of the x-ray system with the applicable field limitation
and alignment requirements of Sec. Sec. 1020.31 and 1020.32.
Radiation therapy simulation system means a radiographic or
fluoroscopic x-ray system intended for localizing the volume to be
exposed during radiation therapy and confirming the position and size of
the therapeutic irradiation field.
Radiography means a technique for generating and recording an x-ray
pattern for the purpose of providing the user with an image(s) after
termination of the exposure.
Rated line voltage means the range of potentials, in volts, of the
supply line specified by the manufacturer at which
[[Page 628]]
the x-ray machine is designed to operate.
Rated output current means the maximum allowable load current of the
x-ray high-voltage generator.
Rated output voltage means the allowable peak potential, in volts,
at the output terminals of the x-ray high-voltage generator.
Rating means the operating limits specified by the manufacturer.
Recording means producing a retrievable form of an image resulting
from x-ray photons.
Scan means the complete process of collecting x-ray transmission
data for the production of a tomogram. Data may be collected
simultaneously during a single scan for the production of one or more
tomograms.
Scan time means the period of time between the beginning and end of
x-ray transmission data accumulation for a single scan.
Solid state x-ray imaging device means an assembly, typically in a
rectangular panel configuration, that intercepts x-ray photons and
converts the photon energy into a modulated electronic signal
representative of the x-ray intensity over the area of the imaging
device. The electronic signal is then used to create an image for
display and/or storage.
Source means the focal spot of the x-ray tube.
Source-image receptor distance (SID) means the distance from the
source to the center of the input surface of the image receptor.
Source-skin distance (SSD) means the distance from the source to the
center of the entrant x-ray field in the plane tangent to the patient
skin surface.
Spot-film device means a device intended to transport and/or
position a radiographic image receptor between the x-ray source and
fluoroscopic image receptor. It includes a device intended to hold a
cassette over the input end of the fluoroscopic image receptor for the
purpose of producing a radiograph.
Stationary tabletop means a tabletop which, when assembled for use,
is incapable of movement with respect to its supporting structure within
the plane of the tabletop.
Technique factors means the following conditions of operation:
(1) For capacitor energy storage equipment, peak tube potential in
kilovolts (kV) and quantity of charge in milliampere-seconds (mAs);
(2) For field emission equipment rated for pulsed operation, peak
tube potential in kV and number of x-ray pulses;
(3) For CT equipment designed for pulsed operation, peak tube
potential in kV, scan time in seconds, and either tube current in
milliamperes (mA), x-ray pulse width in seconds, and the number of x-ray
pulses per scan, or the product of the tube current, x-ray pulse width,
and the number of x-ray pulses in mAs;
(4) For CT equipment not designed for pulsed operation, peak tube
potential in kV, and either tube current in mA and scan time in seconds,
or the product of tube current and exposure time in mAs and the scan
time when the scan time and exposure time are equivalent; and
(5) For all other equipment, peak tube potential in kV, and either
tube current in mA and exposure time in seconds, or the product of tube
current and exposure time in mAs.
Tomogram means the depiction of the x-ray attenuation properties of
a section through a body.
Tube means an x-ray tube, unless otherwise specified.
Tube housing assembly means the tube housing with tube installed. It
includes high-voltage and/or filament transformers and other appropriate
elements when they are contained within the tube housing.
Tube rating chart means the set of curves which specify the rated
limits of operation of the tube in terms of the technique factors.
Useful beam means the radiation which passes through the tube
housing port and the aperture of the beam-limiting device when the
exposure switch or timer is activated.
Variable-aperture beam-limiting device means a beam-limiting device
which has the capacity for stepless adjustment of the x-ray field size
at a given SID.
Visible area means the portion of the input surface of the image
receptor
[[Page 629]]
over which incident x-ray photons are producing a visible image.
X-ray control means a device which controls input power to the x-ray
high-voltage generator and/or the x-ray tube. It includes equipment such
as timers, phototimers, automatic brightness stabilizers, and similar
devices, which control the technique factors of an x-ray exposure.
X-ray equipment means an x-ray system, subsystem, or component
thereof. Types of x-ray equipment are as follows:
(1) Mobile x-ray equipment means x-ray equipment mounted on a
permanent base with wheels and/or casters for moving while completely
assembled;
(2) Portable x-ray equipment means x-ray equipment designed to be
hand-carried; and
(3) Stationary x-ray equipment means x-ray equipment which is
installed in a fixed location.
X-ray field means that area of the intersection of the useful beam
and any one of the set of planes parallel to and including the plane of
the image receptor, whose perimeter is the locus of points at which the
AKR is one-fourth of the maximum in the intersection.
X-ray high-voltage generator means a device which transforms
electrical energy from the potential supplied by the x-ray control to
the tube operating potential. The device may also include means for
transforming alternating current to direct current, filament
transformers for the x-ray tube(s), high-voltage switches, electrical
protective devices, and other appropriate elements.
X-ray subsystem means any combination of two or more components of
an x-ray system for which there are requirements specified in this
section and Sec. Sec. 1020.31 and 1020.32.
X-ray system means an assemblage of components for the controlled
production of x-rays. It includes minimally an x-ray high-voltage
generator, an x-ray control, a tube housing assembly, a beam-limiting
device, and the necessary supporting structures. Additional components
which function with the system are considered integral parts of the
system.
X-ray table means a patient support device with its patient support
structure (tabletop) interposed between the patient and the image
receptor during radiography and/or fluoroscopy. This includes, but is
not limited to, any stretcher equipped with a radiolucent panel and any
table equipped with a cassette tray (or bucky), cassette tunnel,
fluoroscopic image receptor, or spot-film device beneath the tabletop.
X-ray tube means any electron tube which is designed for the
conversion of electrical energy into x-ray energy.
(c) Manufacturers' responsibility. Manufacturers of products subject
to Sec. Sec. 1020.30 through 1020.33 shall certify that each of their
products meet all applicable requirements when installed into a
diagnostic x-ray system according to instructions. This certification
shall be made under the format specified in Sec. 1010.2 of this
chapter. Manufacturers may certify a combination of two or more
components if they obtain prior authorization in writing from the
Director of the Office of Communication, Education, and Radiation
Programs of the Center for Devices and Radiological Health.
Manufacturers shall not be held responsible for noncompliance of their
products if that noncompliance is due solely to the improper
installation or assembly of that product by another person; however,
manufacturers are responsible for providing assembly instructions
adequate to assure compliance of their components with the applicable
provisions of Sec. Sec. 1020.30 through 1020.33.
(d) Assemblers' responsibility. An assembler who installs one or
more components certified as required by paragraph (c) of this section
shall install certified components that are of the type required by
Sec. 1020.31, 1020.32, or 1020.33 and shall assemble, install, adjust,
and test the certified components according to the instructions of their
respective manufacturers. Assemblers shall not be liable for
noncompliance of a certified component if the assembly of that component
was according to the component manufacturer's instruction.
(1) Reports of assembly. All assemblers who install certified
components shall file a report of assembly, except as
[[Page 630]]
specified in paragraph (d)(2) of this section. The report will be
construed as the assembler's certification and identification under
Sec. Sec. 1010.2 and 1010.3 of this chapter. The assembler shall affirm
in the report that the manufacturer's instructions were followed in the
assembly or that the certified components as assembled into the system
meet all applicable requirements of Sec. Sec. 1020.30 through 1020.33.
All assembler reports must be on a form prescribed by the Director,
CDRH. Completed reports must be submitted to the Director, the
purchaser, and, where applicable, to the State agency responsible for
radiation protection within 15 days following completion of the
assembly.
(2) Exceptions to reporting requirements. Reports of assembly need
not be submitted for any of the following:
(i) Reloaded or replacement tube housing assemblies that are
reinstalled in or newly assembled into an existing x-ray system;
(ii) Certified accessory components that have been identified as
such to CDRH in the report required under Sec. 1002.10 of this chapter;
(iii) Repaired components, whether or not removed from the system
and reinstalled during the course of repair, provided the original
installation into the system was reported; or
(iv)(A) Components installed temporarily in an x-ray system in place
of components removed temporarily for repair, provided the temporarily
installed component is identified by a tag or label bearing the
following information:
Temporarily Installed Component
This certified component has been assembled, installed, adjusted, and
tested by me according to the instructions provided by the manufacturer.
Signature
Company Name
Street Address, P.O. Box
City, State, Zip Code
Date of Installation
(B) The replacement of the temporarily installed component by a
component other than the component originally removed for repair shall
be reported as specified in paragraph (d)(1) of this section.
(e) Identification of x-ray components. In addition to the
identification requirements specified in Sec. 1010.3 of this chapter,
manufacturers of components subject to this section and Sec. Sec.
1020.31, 1020.32, and 1020.33, except high-voltage generators contained
within tube housings and beam-limiting devices that are integral parts
of tube housings, shall permanently inscribe or affix thereon the model
number and serial number of the product so that they are legible and
accessible to view. The word ``model'' or ``type'' shall appear as part
of the manufacturer's required identification of certified x-ray
components. Where the certification of a system or subsystem, consisting
of two or more components, has been authorized under paragraph (c) of
this section, a single inscription, tag, or label bearing the model
number and serial number may be used to identify the product.
(1) Tube housing assemblies. In a similar manner, manufacturers of
tube housing assemblies shall also inscribe or affix thereon the name of
the manufacturer, model number, and serial number of the x-ray tube
which the tube housing assembly incorporates.
(2) Replacement of tubes. Except as specified in paragraph (e)(3) of
this section, the replacement of an x-ray tube in a previously
manufactured tube housing assembly certified under paragraph (c) of this
section constitutes manufacture of a new tube housing assembly, and the
manufacturer is subject to the provisions of paragraph (e)(1) of this
section. The manufacturer shall remove, cover, or deface any previously
affixed inscriptions, tags, or labels that are no longer applicable.
(3) Quick-change x-ray tubes. The requirements of paragraph (e)(2)
of this section shall not apply to tube housing assemblies designed and
designated by their original manufacturer to contain quick change x-ray
tubes. The manufacturer of quick-change x-ray tubes shall include with
each replacement tube a label with the tube manufacturer's name, the
model, and serial number of the x-ray tube. The manufacturer of the tube
shall instruct the assembler who installs the new tube to attach the
label to the tube housing assembly and to remove, cover, or deface the
previously affixed inscriptions, tags, or labels that are described by
the
[[Page 631]]
tube manufacturer as no longer applicable.
(f) [Reserved]
(g) Information to be provided to assemblers. Manufacturers of
components listed in paragraph (a)(1) of this section shall provide to
assemblers subject to paragraph (d) of this section and, upon request,
to others at a cost not to exceed the cost of publication and
distribution, instructions for assembly, installation, adjustment, and
testing of such components adequate to assure that the products will
comply with applicable provisions of this section and Sec. Sec.
1020.31, 1020.32, and 1020.33, when assembled, installed, adjusted, and
tested as directed. Such instructions shall include specifications of
other components compatible with that to be installed when compliance of
the system or subsystem depends on their compatibility. Such
specifications may describe pertinent physical characteristics of the
components and/or may list by manufacturer model number the components
which are compatible. For x-ray controls and generators manufactured
after May 3, 1994, manufacturers shall provide:
(1) A statement of the rated line voltage and the range of line-
voltage regulation for operation at maximum line current;
(2) A statement of the maximum line current of the x-ray system
based on the maximum input voltage and current characteristics of the
tube housing assembly compatible with rated output voltage and rated
output current characteristics of the x-ray control and associated high-
voltage generator. If the rated input voltage and current
characteristics of the tube housing assembly are not known by the
manufacturer of the x-ray control and associated high-voltage generator,
the manufacturer shall provide information necessary to allow the
assembler to determine the maximum line current for the particular tube
housing assembly(ies);
(3) A statement of the technique factors that constitute the maximum
line current condition described in paragraph (g)(2) of this section.
(h) Information to be provided to users. Manufacturers of x-ray
equipment shall provide to purchasers and, upon request, to others at a
cost not to exceed the cost of publication and distribution, manuals or
instruction sheets which shall include the following technical and
safety information:
(1) All x-ray equipment. For x-ray equipment to which this section
and Sec. Sec. 1020.31, 1020.32, and 1020.33 are applicable, there shall
be provided:
(i) Adequate instructions concerning any radiological safety
procedures and precautions which may be necessary because of unique
features of the equipment; and
(ii) A schedule of the maintenance necessary to keep the equipment
in compliance with this section and Sec. Sec. 1020.31, 1020.32, and
1020.33.
(2) Tube housing assemblies. For each tube housing assembly, there
shall be provided:
(i) Statements of the leakage technique factors for all combinations
of tube housing assemblies and beam-limiting devices for which the tube
housing assembly manufacturer states compatibility, the minimum
filtration permanently in the useful beam expressed as millimeters (mm)
of aluminum equivalent, and the peak tube potential at which the
aluminum equivalent was obtained;
(ii) Cooling curves for the anode and tube housing; and
(iii) Tube rating charts. If the tube is designed to operate from
different types of x-ray high-voltage generators (such as single-phase
self rectified, single-phase half-wave rectified, single-phase full-wave
rectified, 3-phase 6-pulse, 3-phase 12-pulse, constant potential,
capacitor energy storage) or under modes of operation such as alternate
focal spot sizes or speeds of anode rotation which affect its rating,
specific identification of the difference in ratings shall be noted.
(3) X-ray controls and generators. For the x-ray control and
associated x-ray high-voltage generator, there shall be provided:
(i) A statement of the rated line voltage and the range of line-
voltage regulation for operation at maximum line current;
(ii) A statement of the maximum line current of the x-ray system
based on the maximum input voltage and output
[[Page 632]]
current characteristics of the tube housing assembly compatible with
rated output voltage and rated current characteristics of the x-ray
control and associated high-voltage generator. If the rated input
voltage and current characteristics of the tube housing assembly are not
known by the manufacturer of the x-ray control and associated high-
voltage generator, the manufacturer shall provide necessary information
to allow the purchaser to determine the maximum line current for his
particular tube housing assembly(ies);
(iii) A statement of the technique factors that constitute the
maximum line current condition described in paragraph (h)(3)(ii) of this
section;
(iv) In the case of battery-powered generators, a specification of
the minimum state of charge necessary for proper operation;
(v) Generator rating and duty cycle;
(vi) A statement of the maximum deviation from the preindication
given by labeled technique factor control settings or indicators during
any radiographic or CT exposure where the equipment is connected to a
power supply as described in accordance with this paragraph. In the case
of fixed technique factors, the maximum deviation from the nominal fixed
value of each factor shall be stated;
(vii) A statement of the maximum deviation from the continuous
indication of x-ray tube potential and current during any fluoroscopic
exposure when the equipment is connected to a power supply as described
in accordance with this paragraph; and
(viii) A statement describing the measurement criteria for all
technique factors used in paragraphs (h)(3)(iii), (h)(3)(vi), and
(h)(3)(vii) of this section; for example, the beginning and endpoints of
exposure time measured with respect to a certain percentage of the
voltage waveform.
(4) Beam-limiting device. For each variable-aperture beam-limiting
device, there shall be provided;
(i) Leakage technique factors for all combinations of tube housing
assemblies and beam-limiting devices for which the beam-limiting device
manufacturer states compatibility; and
(ii) A statement including the minimum aluminum equivalent of that
part of the device through which the useful beam passes and including
the x-ray tube potential at which the aluminum equivalent was obtained.
When two or more filters are provided as part of the device, the
statement shall include the aluminum equivalent of each filter.
(5) Imaging system information. For x-ray systems manufactured on or
after June 10, 2006, that produce images using the fluoroscopic image
receptor, the following information shall be provided in a separate,
single section of the user's instruction manual or in a separate manual
devoted to this information:
(i) For each mode of operation, a description of the mode and
detailed instructions on how the mode is engaged and disengaged. The
description of the mode shall identify those technique factors and
system controls that are fixed or automatically adjusted by selection of
the mode of operation, including the manner in which the automatic
adjustment is controlled. This information shall include how the
operator can recognize which mode of operation has been selected prior
to initiation of x-ray production.
(ii) For each mode of operation, a descriptive example(s) of any
specific clinical procedure(s) or imaging task(s) for which the mode is
recommended or designed and how each mode should be used. Such
recommendations do not preclude other clinical uses.
(6) Displays of values of AKR and cumulative air kerma. For
fluoroscopic x-ray systems manufactured on or after June 10, 2006, the
following shall be provided:
(i) A schedule of maintenance for any system instrumentation
associated with the display of air kerma information necessary to
maintain the displays of AKR and cumulative air kerma within the limits
of allowed uncertainty specified by Sec. 1020.32(k)(6) and, if the
capability for user calibration of the display is provided, adequate
instructions for such calibration;
(ii) Identification of the distances along the beam axis:
(A) From the focal spot to the isocenter, and
[[Page 633]]
(B) From the focal spot to the reference location to which displayed
values of AKR and cumulative air kerma refer according to Sec.
1020.32(k)(4);
(iii) A rationale for specification of a reference irradiation
location alternative to 15 cm from the isocenter toward the x-ray source
along the beam axis when such alternative specification is made
according to Sec. 1020.32(k)(4)(ii).
(i) [Reserved]
(j) Warning label. The control panel containing the main power
switch shall bear the warning statement, legible and accessible to view:
``Warning: This x-ray unit may be dangerous to patient and operator
unless safe exposure factors, operating instructions and maintenance
schedules are observed.''
(k) Leakage radiation from the diagnostic source assembly. The
leakage radiation from the diagnostic source assembly measured at a
distance of 1 meter in any direction from the source shall not exceed
0.88 milligray (mGy) air kerma (vice 100 milliroentgen (mR) exposure) in
1 hour when the x-ray tube is operated at the leakage technique factors.
If the maximum rated peak tube potential of the tube housing assembly is
greater than the maximum rated peak tube potential for the diagnostic
source assembly, positive means shall be provided to limit the maximum
x-ray tube potential to that of the diagnostic source assembly.
Compliance shall be determined by measurements averaged over an area of
100 square cm with no linear dimension greater than 20 cm.
(l) Radiation from components other than the diagnostic source
assembly. The radiation emitted by a component other than the diagnostic
source assembly shall not exceed an air kerma of 18 microGy (vice 2 mR
exposure) in 1 hour at 5 cm from any accessible surface of the component
when it is operated in an assembled x-ray system under any conditions
for which it was designed. Compliance shall be determined by
measurements averaged over an area of 100 square cm with no linear
dimension greater than 20 cm.
(m) Beam quality--(1) Half-value layer (HVL). The HVL of the useful
beam for a given x-ray tube potential shall not be less than the
appropriate value shown in table 1 in paragraph (m)(1) of this section
under the heading ``Specified Dental Systems,'' for any dental x-ray
system designed for use with intraoral image receptors and manufactured
after December 1, 1980; under the heading ``I--Other X-Ray Systems,''
for any dental x-ray system designed for use with intraoral image
receptors and manufactured before December 1, 1980, and all other x-ray
systems subject to this section and manufactured before June 10, 2006;
and under the heading ``II--Other X-Ray Systems,'' for all x-ray
systems, except dental x-ray systems designed for use with intraoral
image receptors, subject to this section and manufactured on or after
June 10, 2006. If it is necessary to determine such HVL at an x-ray tube
potential which is not listed in table 1 in paragraph (m)(1) of this
section, linear interpolation or extrapolation may be made. Positive
means\2\ shall be provided to ensure that at least the minimum
filtration needed to achieve the above beam quality requirements is in
the useful beam during each exposure. Table 1 follows:
---------------------------------------------------------------------------
\2\ In the case of a system, which is to be operated with more than
one thickness of filtration, this requirement can be met by a filter
interlocked with the kilovoltage selector which will prevent x-ray
emissions if the minimum required filtration is not in place.
[[Page 634]]
Table 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
X-Ray Tube Voltage (kilovolt peak) Minimum HVL (mm of aluminum)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Measured Operating Specified Dental I--Other X-Ray II--Other X-Ray
Designed Operating Range Potential Systems\1\ Systems\2\ Systems\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Below 51 30 1.5 0.3 0.3
40 1.5 0.4 0.4
50 1.5 0.5 0.5
51 to 70 51 1.5 1.2 1.3
60 1.5 1.3 1.5
70 1.5 1.5 1.8
Above 70 71 2.1 2.1 2.5
80 2.3 2.3 2.9
90 2.5 2.5 3.2
100 2.7 2.7 3.6
110 3.0 3.0 3.9
120 3.2 3.2 4.3
130 3.5 3.5 4.7
140 3.8 3.8 5.0
150 4.1 4.1 5.4
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Dental x-ray systems designed for use with intraoral image receptors and manufactured after December 1, 1980.
\2\ Dental x-ray systems designed for use with intraoral image receptors and manufactured before or on December 1, 1980, and all other x-ray systems
subject to this section and manufactured before June 10, 2006.
\3\ All x-ray systems, except dental x-ray systems designed for use with intraoral image receptors, subject to this section and manufactured on or after
June 10, 2006.
[[Page 635]]
(2) Optional filtration. Fluoroscopic systems manufactured on or
after June 10, 2006, incorporating an x-ray tube(s) with a continuous
output of 1 kilowatt or more and an anode heat storage capacity of 1
million heat units or more shall provide the option of adding x-ray
filtration to the diagnostic source assembly in addition to the amount
needed to meet the HVL provisions of Sec. 1020.30(m)(1). The selection
of this additional x-ray filtration shall be either at the option of the
user or automatic as part of the selected mode of operation. A means of
indicating which combination of additional filtration is in the x-ray
beam shall be provided.
(3) Measuring compliance. For capacitor energy storage equipment,
compliance shall be determined with the maximum selectable quantity of
charge per exposure.
(n) Aluminum equivalent of material between patient and image
receptor. Except when used in a CT x-ray system, the aluminum equivalent
of each of the items listed in table 2 in paragraph (n) of this section,
which are used between the patient and image receptor, may not exceed
the indicated limits. Compliance shall be determined by x-ray
measurements made at a potential of 100 kilovolts peak and with an x-ray
beam that has an HVL specified in table 1 in paragraph (m)(1) of this
section for the potential. This requirement applies to front panel(s) of
cassette holders and film changers provided by the manufacturer for
patient support or for prevention of foreign object intrusions. It does
not apply to screens and their associated mechanical support panels or
grids. Table 2 follows:
Table 2
------------------------------------------------------------------------
Maximum Aluminum
Item Equivalent
(millimeters)
------------------------------------------------------------------------
1. Front panel(s) of cassette holders (total of all) 1.2
2. Front panel(s) of film changer (total of all) 1.2
3. Cradle 2.3
4. Tabletop, stationary, without articulated joints 1.2
5. Tabletop, movable, without articulated joint(s) 1.7
(including stationary subtop)
6. Tabletop, with radiolucent panel having one 1.7
articulated joint
7. Tabletop, with radiolucent panel having two or 2.3
more articulated joints
8. Tabletop, cantilevered 2.3
9. Tabletop, radiation therapy simulator 5.0
------------------------------------------------------------------------
(o) Battery charge indicator. On battery-powered generators, visual
means shall be provided on the control panel to indicate whether the
battery is in a state of charge adequate for proper operation.
(p) [Reserved]
(q) Modification of certified diagnostic x-ray components and
systems. (1) Diagnostic x-ray components and systems certified in
accordance with Sec. 1010.2 of this chapter shall not be modified such
that the component or system fails to comply with any applicable
provision of this chapter unless a variance in accordance with Sec.
1010.4 of this chapter or an exemption under section 534(a)(5) or 538(b)
of the Federal Food, Drug, and Cosmetic Act has been granted.
(2) The owner of a diagnostic x-ray system who uses the system in a
professional or commercial capacity may modify the system, provided the
modification does not result in the failure of the system or component
to comply with the applicable requirements of this section or of Sec.
1020.31, 1020.32, or 1020.33. The owner who causes such modification
need not submit the reports required by subpart B of part 1002 of this
chapter, provided the owner records the date and the details of the
modification in the system records and maintains this information, and
provided the modification of the x-ray system does not result in a
failure to comply with Sec. 1020.31, 1020.32, or 1020.33.
[71 FR 34028, June 10, 2006, as amended at 72 FR 17401, Apr. 9, 2007]