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between the patient and image recep ports required by subpart B of part 1002 tor, may not exceed the indicated lim of this chapter, provided the owner its. Compliance shall be determined by records the date and the details of the X-ray measurements made at a poten- modification, and provided the moditial of 100 kilovolts peak and with an x fication of the x-ray system does not ray beam that has a HVL of 2.7 milli- result in a failure to comply with neters of aluminum. This requirement $ 1020.31, § 1020.32, or $ 1020.33. applies to front panel(s) of cassette zolders and film changers provided by

(58 FR 26396, May 3, 1993, as amended at 59

FR 26403, May 19, 1994; 64 FR 35927, July 2, he manufacturer for patient support

1999; 65 FR 17138, Mar. 31, 2000) yr for prevention of foreign object inrusions. It does not apply to screens

EFFECTIVE DATE NOTE: At 70 FR 34028, June ind their associated mechanical sup

10, 2005, $1020.30 was revised, effective June

10, 2006. For the convenience of the user the sort panels or grids.

revised text is set forth as follows: TABLE II

8 1020.30 Diagnostic x-ray systems and their

major components.

Aluminum
Item

(a) Applicability. (1) The provisions of this (millimeters) section are applicable to:

(i) The following components of diagnostic ront panel(s) of cassette holder (total of all) ront panel(s) of film changer (total of all) ....

1.0

X-ray systems: radle .......

2.0 (A) Tube housing assemblies, x-ray conabletop, stationary, without articulated

trols, X-ray high-voltage generators, X-ray joint(s)

tables, cradles, film changers, vertical casabletop. movable, without articulated

sette holders mounted in a fixed location and joint(s) (including stationary subtop) .......

1.5

cassette holders with front panels, and beamabletop, with radiolucent panel having one articulated joint

1.5

limiting devices manufactured after August abletop, with radiolucent panel having two

1, 1974. or more articulated joints

(B) Fluoroscopic imaging assemblies manabletop, cantilevered

ufactured after August 1, 1974, and before abletop, radiation therapy simulator

5.0

April 26, 1977, or after June 10, 2006.

(C) Spot-film devices and image intensi(0) Battery charge indicator. On bat

fiers manufactured after April 26, 1977. ery-powered generators, visual means (D) Cephalometric devices manufactured hall be provided on the control panel after February 25, 1978. o indicate whether the battery is in a (E) Image receptor support devices for tate of charge adequate for proper op

mammographic X-ray systems manufactured ration.

after September 5, 1978.

(F) Image receptors that are electrically (p) (Reserved)

powered or connected with the x-ray system (q) Modification of certified diagnostic

manufactured on or after June 10, 2006. -ray components and systems-(1) Diag

(G) Fluoroscopic air kerma display devices ostic x-ray components and systems

manufactured on or after June 10, 2006. ertified in accordance with $ 1010.2 of (ii) Diagnostic x-ray systems, except comhis chapter shall not be modified such puted tomography X-ray systems, incorhat the component or system fails to porating one or more of such components; omply with any applicable provision

however, such X-ray systems shall be ref this chapter unless a variance in ac

quired to comply only with those provisions ordance with § 1010.4 of this chapter or

of this section and $$ 1020.31 and 1020.32,

which relate to the components certified in n exemption under sections 358(a)(5)

accordance with paragraph (c) of this section r 360B(b) of the Public Health Service

and installed into the systems. .ct has been granted.

(iii) Computed tomography (CT) x-ray sys(2) The owner of a diagnostic x-ray tems manufactured before November 29, 1984. ystem who uses the system in a pro (iv) CT gantries manufactured after Sepissional or commercial capacity may tember 3, 1985. lodify the system, provided the modi

(2) The following provisions of this section cation does not result in the failure of

and $1020.33 are applicable to CT X-ray sys

tems manufactured or remanufactured on or de system or component to comply

after November 29, 1984: ith the applicable requirements of

(i) Section 1020.30(a); his section or of g 1020.31, § 1020.32, or (ii) Section 1020.30(b) "Technique factors''; 1020.33. The owner who causes such (iii) Section 1020.30(b) "CT," "Dose," codification need not submit the re- "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);

(vii) Section 1020.33(c)(1) as it affects $ 1020.33(c)(2); and

(viii) Section 1020.33(c)(2).

(3) The provisions of this section and $ 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 88 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.

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 erposure control (AEC) means a device which automatically controls one of more technique factors in order to obtain a: 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 aris 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 Xray 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 re spect to the patient without moving the pi tient.

Cantilevered tabletop means a tabletop de signed such that the unsupported portion cao be extended at least 100 cm beyond the sup port.

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 ID tended 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 mean value of a population of observations. It is estimated using the following equation:

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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where: 1 = Estimated standard deviation of the population.

= Mean value of observations in sample. d = ith observation sampled. 1 = Number of observations sampled.

Computed tomography (CT) means the proluction of a tomogram by the acquisition nd computer processing of x-ray transnission data. Control panel means that part of the x-ray ontrol upon which are mounted the switchs, knobs, pushbuttons, and other hardware lecessary for manually setting the technique actors.

Cooling curve means the graphical relationhip between heat units stored and cooling ime. Cradle means: (1) A removable device which supports and nay restrain a patient above an x-ray table;

(2) A device; (1) Whose patient support structure is iterposed between the patient and the nage receptor during normal use; (ii) Which is equipped with means for paient restraint; and (iii) Which is capable of rotation about its ing (longitudinal) axis. CT gantry means tube housing assemblies, eam-limiting devices, detectors, and the apporting structures, frames, and covers hich hold and/or enclose these components. Cumulative air kerma means the total air erma accrued from the beginning of an exmination or procedure and includes all conributions from fluoroscopic and radioraphic irradiation. Diagnostic source assembly means the tube pusing assembly with a beam-limiting deIce attached. Diagnostic x-ray system means an x-ray sysm designed for irradiation of any part of le human body for the purpose of diagnosis : visualization. Dose means the absorbed dose as defined by le International Commission on Radiation nits and Measurements. The absorbed dose, , is the quotient of de by dm, where de is le mean energy imparted to matter of mass n; thus D=de/dm, in units of J/kg, where le special name for the unit of absorbed se 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 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 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 dEx by dm, where dEx 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=dEv/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.

teral Nuoroscope 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 as sembly 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 expo

sures 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 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 par allel 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(V.

V;)/Vi
where:
Vo = No-load line potential and
Vi = Load line potential.

Marimum 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 as sociated 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 re ceptor, and photospot recording. In a specife 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 op tical aperture, may be adjustable or may vary; their variation per se does not com prise 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 more ment 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 ralue of the potential difference across the x-ray tube during an exposure.

Primary protective barrier means the mateial, excluding filters, placed in the useful leam to reduce the radiation exposure for protection purposes.

Pulsed mode means operation of the x-ray ystem such that the x-ray tube current is ulsed by the x-ray control to produce one or nore exposure intervals of duration less han one-half second. Quick change X-ray tube means an x-ray ube designed for use in its associated tube ousing such that: (1) The tube cannot be inserted in its housng in a manner that would result in nonompliance of the system with the requirenents of paragraphs (k) and (m) of this secion: (2) The focal spot position will not cause oncompliance with the provisions of this ection or $ 1020.31 or 1020.32;

(3) The shielding within the tube housing annot be displaced; and

(4) Any removal and subsequent replacenent of a beam-limiting device during reoading of the tube in the tube housing will lot result in noncompliance of the x-ray sysem with the applicable field limitation and lignment requirements of $$ 1020.31 and 020.32.

Radiation therapy simulation system means a adiographic or fluoroscopic x-ray system inended for localizing the volume to be exosed during radiation therapy and conirming the position and size of the theraleutic irradiation field.

Radiography means a technique for generting and recording an x-ray pattern for the purpose of providing the user with an mage(s) after termination of the exposure.

Rated line voltage means the range of potenials, in volts, of the supply line specified by he manufacturer at which the x-ray mahine is designed to operate. Rated output current means the maximum llowable load current of the x-ray high-voltge generator. Rated output voltage means the allowable eak potential, in volts, at the output termials of the x-ray high-voltage generator. Rating means the operating limits specified y the manufacturer. Recording means producing a retrievable orm of an image resulting from x-ray phoons. Scan means the complete process of col'cting X-ray transmission data for the prouction of a tomogram. Data may be colcted simultaneously during a single scan or the production of one or more omograms.

Scan time means the period of time between the beginning and end of x-ray transmission data accumulation for a single scan.

Solid state I-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, Xray 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

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