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should be routinely considered for use. Electronic oscillators.

As a basis for judgment, specific area Sound amplification equipment.

testicular shielding should be considUltrasonic: Cauterizers.

ered for all examinations of male paCell and tissue disintegrators.

tients in which the pubic symphysis Cleaners.

will be visualized on the film; Diagnostic and nondestructive testing (3) Specific area gonad shielding equipment.

should never be used as a substitute for Ranging and detection equipment.

careful patient positioning, the use of

correct technique factors and film Subpart C-Radiation Protection

processing, or proper beam limitation Recommendations

(confinement of the x-ray field to the

area of diagnostic interest), because $1000.50 Recommendation for the use of specific area gonad shielding on

this could result in unnecessary doses patients during medical diagnostic

to other sensitive tissues and could adX-ray procedures.

versely affect the quality of the Specific area gonad shielding covers

radiograph; and in area slightly larger than the region

(4) Specific area gonad shielding of the gonads. It may therefore be used

should provide attenuation of x-rays at without interfering with the objectives

least equivalent to that afforded by 0.25 of the examination to protect the ger

millimeter of lead. ninal tissue of patients from radiation (b) The clinical objectives of the exExposure that may cause genetic amination will not be compromised. mutations during many medical x-ray (1) Specific area testicular shielding procedures in which the gonads lie usually does not obscure needed inforwithin or are in close proximity to the mation except in a few cases such as (-ray field. Such shielding should be oblique views of the hip, retrograde provided when the following conditions urethrograms and

voiding »xist:

cystourethrograms, visualization of (a) The gonads will lie within the pri the rectum and, occasionally, the pubic nary x-ray field, or within close prox

symphysis. Consequently, specific area mity (about 5 centimeters), despite

testicular shielding should be considproper beam limitation. Except as pro

ered for use in the majority of x-ray exvided in paragraph (b) or (c) of this sec

aminations of male patients in which tion:

the testes will lie within the primary (1) Specific area testicular shielding

beam or within 5 centimeters of its should always be used during those ex

edge. It is not always possible to posiaminations in which the testes usually

tion shields on male patients so that are in the primary x-ray field, such as

no bone is obscured. Therefore, if all examinations of the pelvis, hip, and

bone structure of the pelvic area must apper femur; (2) Specific area testicular shielding

be visualized for a particular patient, may also be warranted during other ex

the use of shielding should be carefully aminations of the abdominal region in

evaluated. The decision concerning the which the testes may lie within or in

applicability of shielding for an indiclose proximity to the primary X-ray

vidual patient is dependent upon confield, depending upon the size of the pa

sideration of the patient's unique antient and the examination techniques

thropometric characteristics and the and equipment employed. Some exam

diagnostic information needs of the exples of these are: Abdominal, lumbar

amination. spine and lumbosacral spine examina

(2) The use of specific area ovarian tions, intravenous pyelograms, and ab shielding is frequently impractical at dominal scout film for barium enemas present because the exact location of and upper GI series. Each x-ray facility the ovaries is difficult to estimate, and should evaluate its procedures, tech- the shield may obscure visualization of niques, and equipment and compile a portions of adjacent structures such as list of such examinations for which the spine, ureters, and small and large specific area testicular shielding bowels. However, it may be possible for

practitioners to use specific area ovar ian shielding during selected views in some examinations.

(c) The patient has a reasonable reproductive potential.

(1) Specific area shielding need not be used on patients who cannot or are not likely to have children in the future.

(2) The following table of statistical data regarding the average number of children expected by potential parents in various age categories during their remaining lifetimes is provided for xray facilities that wish to use it as a basis for judging reproductive potential:

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(2) Quality assurance means the planned and systematic actions that provide adequate confidence that a diagnostic X-ray facility will produce consistently high quality images with minimum exposure of the patients and healing arts personnel. The determination of what constitutes high quality will be made by the facility producing the images. Quality assurance actions include both “quality control” techniques and "quality administration" procedures.

(3) Quality assurance program means an organized entity designed to provide “quality assurance' for a diagnostic radiology facility. The nature and extent of this program will vary with the size and type of the facility, the type of examinations conducted, and other factors.

(4) Quality control techniques are those techniques used in the monitoring (or testing) and maintenance of the components of an x-ray system. The quality control techniques thus are concerned directly with the equipment.

(5) Quality administration procedures are those management actions intended to guarantee that monitoring techniques are properly performed and evaluated and that necessary corrective measures are taken in response to monitoring results. These procedures provide the organizational framework for the quality assurance program.

(6) X-ray system means an assemblage of components for the controlled production of diagnostic images with Arays. It includes minimally an x-ray high voltage generator, an X-ray control, a tube-housing assembly, a beamlimiting device, and the necessary supporting structures. Other components that function with the system, such as image receptors, image processors, view boxes, and darkrooms, are also parts of the system.

(c) Elements. A quality assurance program should contain the elements listed in paragraphs (c)(1) through (10) of this section. The extent to which each element of the quality assurance program is implemented should be determined by an analysis of the facility's objectives and resources conducted by its qualified staff or by qualified outside consultants. The extent of implementation should be determined on the

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1 Derived from data published by the National Center for Health Statistics, "Final Natality Statistics 1970," HRA 741120, vol. 22, No. 12, Mar. 20, 1974.

[41 FR 30328, July 23, 1976; 41 FR 31812, July 30, 1976)

8 1000.55 Recommendation for quality

assurance programs in diagnostic

radiology facilities. (a) Applicability. Quality assurance programs as described in paragraph (c) of this section are recommended for all diagnostic radiology facilities.

(b) Definitions. As used in this section, the following definitions apply:

(1) Diagnostic radiology facility means any facility in which an X-ray system(s) is used in any procedure that in volves irradiation of any part of the human body for the purpose of diagnosis or visualization. Offices of individual physicians, dentists, podiatrists, and chiropractors, as well as mobile laboratories, clinics, and hospitals are all examples of diagnostic radiology facilities.

sis of whether the expected benefits (vi) In large facilities, responsibility radiation exposure reduction, im- for long-range planning of quality asved image quality, and/or financial surance goals and activities should be rings will compensate for the re assigned to a quality assurance comirces required for the program.

mittee as described in paragraph (c)(9) 1) Responsibility. (i) Responsibility of this section. d authority for the overall quality (2) Purchase specifications. Before pursurance program as well as for moni- chasing new equipment, the staff of the ing, evaluation, and corrective diagnostic radiology facility should deasures should be specified and re- termine the desired performance specirded in a quality assurance manual. fications for the equipment. Initially, ii) The owner or practitioner in these specifications may be stated in arge of the facility has primary re- terms of the desired performance of the onsibility for implementing and equipment, or prospective vendors may tintaining the quality assurance pro- be informed solely of the functions the am.

equipment should be able to perform iii) Staff technologists will gen- and asked to provide the performance ally be delegated a basic quality as- specifications of items from their rance role by the practitioner in equipment line that can perform these arge. Responsibility for specific functions. In either case, the responses lality control monitoring and main of the prospective vendors should serve nance techniques or quality adminis- as the basis for negotiations to estabation procedures may be assigned, lish the final purchase specifications, ovided that the staff technologists taking into account the state of the art e qualified by training or experience and balancing the need for the specir these duties. The staff tech fied performance levels with the cost of blogists should also be responsible for the equipment to meet them. The final lentifying problems or potential prob purchase specifications should be in ms requiring actions beyond the level writing and should include perform

their training. They should bring ance specifications. The availability of iese problems to the attention of the experienced service personnel should ractitioner in charge, or his or her also be taken into consideration in epresentative, so that assistance in making the final purchase decisions. olving the problems may be obtained Any understandings with respect to 'om inside or outside the facility.

service personnel should be incor(iv) In facilities where they are avail- porated into the purchase specificable, physicists, supervisory tech- tions. After the equipment is installed, ologists, or quality control tech- the facility should conduct a testing ologists should have a major role in program, as defined in its purchase he quality assurance program. Such specifications, to ensure that the pecialized personnel may be assigned equipment meets the agreed upon specesponsibility for day-to-day adminis- ifications, including applicable Federal ration of the program, may carry out and State regulatory requirements. nonitoring duties beyond the level of The equipment should not be formally raining of the staff technologist or, if accepted until any necessary correclesired by the facility, may relieve the tions have been made by the vendor. staff technologists of some or all of The purchase specifications and the jheir basic monitoring duties. Staff records of the acceptance testing service engineers may also be assigned should be retained throughout the life responsibility for certain preventive or of the equipment for comparison with corrective maintenance actions.

monitoring results in order to assess (v) Responsibility for certain quality continued acceptability of performcontrol techniques and corrective ance. measures may be assigned to personnel (3) Monitoring and maintenance. A qualified by training or experience, routine quality control monitoring and such as consultants or industrial rep- maintenance system incorporating resentatives, from outside of the facil- state-of-the-art procedures should be ity, provided there is a written agree- established and conducted on a regular ment clearly specifying these services. schedule. The purpose of monitoring is

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to permit evaluation of the performance of the facility's X-ray system(s) in terms of the standards for image quality established by the facility (as described in paragraph (c)(4) of this section) and compliance with applicable Federal and State regulatory requirements. The maintenance program should include corrective maintenance to eliminate problems revealed by monitoring or other means before they have a serious deleterious impact on patient care. To the extent permitted by the training of the facility staff, the maintenance program should also include preventive maintenance, which could prevent unexpected breakdowns of equipment and disruption of departmental routine.

(i) The parameters to be monitored in a facility should be determined by that facility on the basis of an analysis of expected benefits and cost. Such factors as the size and resources of the facility, the type of examinations conducted, and the quality assurance problems that have occurred in that or similar facilities should be taken into account in establishing the monitoring system. The monitoring frequency should also be based upon need and can be different for different parameters.

(ii) Although the parameters to be monitored will vary somewhat from facility to facility, every diagnostic radiology facility should consider monitoring the following five key components of the x-ray system:

(a) Film processing.

(6) Basic performance characteristics of the x-ray unit.

(c) Cassettes and grids.
(d) View boxes.
(e) Darkroom.

(iii) Examples of parameters of the above-named components and of more specialized equipment that may be monitored are as follows:

(a) For film processing:
An index of speed.
An index of contrast.
Base plus fog.
Solution temperatures.
Film artifact identification.

(6) For basic performance characteristics of the x-ray unit:

(1) For fluoroscopic x-ray units: Table-top exposure rates. Centering alignment.

Collimation.
kVp accuracy and reproducibility.
mA accuracy and reproducibility.
Exposure time accuracy and reproducibility.
Reproducibility of x-ray output.
Focal spot size consistency.
Half-value layer.
Representative entrance skin exposures.

(2) For image-intensified systems:
Resolution.
Focusing.
Distortion.
Glare.
Low contrast performance.
Physical alignment of camera and colli-
mating lens.

(3) For radiographic x-ray units: Reproducibility of x-ray output. Linearity and reproducibility of mA sta

tions. Reproducibility and accuracy of timer sta

tions. Reproducibility and accuracy of kVp sta

tions.
Accuracy of source-to-film distance indica-

tors.
Light/x-ray field congruence.
Half-value layer.
Focal spot size consistency.
Representative entrance skin exposures.

(4) For automatic exposure control devices: Reproducibility. kVp compensation. Field sensitivity matching. Minimum response time. Backup timer verification.

(c) For cassettes and grids:

(1) For cassettes:
Film/screen contact.
Screen condition.
Light leaks.
Artifact identification.

(2) For grids:
Alignment and focal distance.
Artifact identification.

(d) For view boxes: Consistency of light output with time. Consistency of light output from one box to

another. View box surface conditions.

(e) For darkrooms: Darkroom integrity. Safe light conditions.

For specialized equipment: (1) For tomographic systems: Accuracy of depth and cut indicator.

Thickness of cut plane.
Exposure angle.
Completeness of tomographic motion.
Flatness of tomographic field.
Resolution.
Continuity of exposure.
Platness of cassette.
Representative entrance skin exposures.

(2) For computerized tomography:
Precision (noise).
'ontrast scale.
ligh and low contrast resolution.
Alignment.
Lepresentative entrance skin exposures.

(iv) The maintenance program should nclude both preventive and corrective spects.

(a) Preventive maintenance. Preventive naintenance should be performed on a egularly scheduled basis with the goal of preventing breakdowns due to equipnent failing without warning signs deectable by monitoring. Such actions lave been found cost effective if reponsibility is assigned to facility staff nembers. Possible preventive maintelance procedures are visual inspection If the mechanical and electrical charcteristics of the x-ray system (covring such things as checking condiions of cables, watching the tomoTaphic unit for smoothness of motion, ssuring cleanliness with respect to pilling of contaminants in the examnation room or the darkroom, and lisening for unusual noises in the movng parts of the system), following the nanufacturer's recommended procelures for cleaning and maintenance of he equipment, and regular inspection nd replacement of switches and parts hat routinely wear out or fail. The rocedures included would depend upon he background of the staff members .vailable. Obviously, a large facility vith its own service engineers can do nore than an individual practitioner's office.

(6) Corrective maintenance. For maxmum effectiveness, the quality assurince program should make provision, 18 described in paragraph (c)(5) of this lection, for ascertaining whether poential problems are developing. If poential or actual problems are deected, corrective maintenance should e carried out to eliminate them before hey cause a major impact on patient are.

(4) Standards for image quality. Standards of acceptable image quality should be established. Ideally, these should be objective, e.g., acceptability limits for the variations of parameter values, but they may be subjective, e.g., the opinions of professional personnel, in cases where adequate objective standards cannot be defined. These standards should be routinely reviewed and redefined as needed, as described in paragraph (c)(10) of this section.

(5) Evaluation. The facility's quality assurance program should include means for two levels of evaluation.

(i) On the first level, the results of the monitoring procedures should be used to evaluate the performance of the X-ray system(s) to determine whether corrective actions are needed to adjust the equipment so that the image quality consistently meets the standards for image quality. This evaluation should include analysis of trends in the monitoring data as well as the use of the data to determine the need for corrective actions on a day-byday basis. Comparison of monitoring data with the purchase specifications and acceptance testing results for the equipment in question is also useful.

(ii) On the second level, the facility quality assurance program should also include means for evaluating the effectiveness of the program itself. Possible means include ongoing studies of the retake rate and the causes of the repeated radiographs, examination of equipment repair and replacement costs, subjective evaluation of the radiographs being produced, occurrence and reasons for complaints by radiologists, and analysis of trends in the results of monitoring procedures such as sensitometric studies. Of these, ongoing studies of the retake rate (reject rate) and its causes are often the most useful and may also provide information of value in the first level of evaluation. Such studies can be used to evaluate potential for improvement, to make corrections, and to determine whether the corrective actions were effective. The number of rejects should be recorded daily or weekly, depending on the facility's analysis of its needs. Ideally, the reasons for the rejection

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