1. (a) Purpose and scope.

   1. (1) This section establishes requirements for the use of radiation machines in the healing arts and in the practice of veterinary medicine. All usage of such machines under this section shall be made by or under the supervision of a practitioner of the healing arts or licensed veterinarian. The usage of mammography radiation machines is exempt from this section and is covered in §289.230 of this title (relating to Certification of Mammography Systems), with the exceptions listed in §289.230(c)(1) and (2) of this title.
   2. (2) The registrant shall be responsible for directing the operation of the radiation machines under the administrative control of the registrant. The registrant shall assure that the requirements of this section are met in the operation of such radiation machines.
   3. (3) In addition to the requirements of this section, all registrants, unless otherwise specified, are subject to the requirements of §289.112 of this title (relating to Hearing and Enforcement Procedures), §289.114 of this title (relating to Notices, Instructions, and Reports to Workers; Inspections), §289.201 of this title (relating to General Provisions), §289.202 of this title (relating to Standards for Protection Against Radiation), §289.204 of this title (relating to Fees for Certificates of Registration, Radioactive Material(s) Licenses, Emergency Planning and Implementation, and Other Regulatory Services), and §289.226 of this title (relating to Registration of Radiation Machine Use and Services).

2. (b) Prohibitions.

   1. (1) The agency may prohibit use of machines that pose significant threat or endanger public health and safety, in accordance with §289.112 of this title and §289.201 of this title.

   2. (2) Individuals shall not be exposed to the useful beam except for healing arts purposes and unless such exposure has been authorized by a licensed practitioner of the healing arts. This provision specifically prohibits deliberate exposure for the following purposes:

      1. (A) exposure of an individual for training, demonstration, or other non-healing arts purposes;
      2. (B) exposure of an individual for the purpose of healing arts screening except as authorized by subsection (f)(1) of this section; and
      3. (C) exposure of an individual for the purpose of research except as authorized by subsection (f)(2) of this section.
   3. (3) Non-image-intensified fluoroscopic equipment shall not be used.

3. (c) Exemptions.

   1. (1) Individuals who operate only dental radiographic systems for diagnostic purposes are exempt from the personnel monitoring requirements of §289.202(q) of this title.
   2. (2) Portable units designed to be hand-held are exempt from the requirements of subsection (o)(2) of this section. The portable unit must be held by the tube housing support or handle.
   3. (3) Veterinary facilities are exempt from the aural communication requirements of computed tomography (CT) in subsection (v)(2)(A) of this section and therapy systems in subsections (x)(2)(A) and (y)(2)(D) of this section.

   4. (4) Individuals who are sole practitioners and sole operators and the only occupationally exposed individual are exempt from the following requirements:

      1. (A) 22.11 of Texas Regulations for Control of Radiation (TRCR) Part 22 as adopted by reference in §289.114 of this title; and
      2. (B) subsection (e)(2) of this section.
   5. (5) In accordance with the Dental Practice Act, Texas Civil Statutes, Article 4551o, dental practices are exempt from the Medical Physics Practice Act, Texas Civil Statutes, Article 4512n. Dentists required to have tests performed in accordance with subsection (q)(5) of this section may select any qualified person authorized by registration through the Bureau of Radiation Control.
   6. (6) Registrants are exempt from the posting of the radiation area requirements in §289.202(aa)(1) of this title provided that the operator has continuous surveillance and access control of the radiation area.
   7. (7) All healing arts and veterinary medicine registrants are exempt from the radiation protection program requirements of §289.202(e).

4. (d) Definitions. The following words and terms when used in this section shall have the following meaning unless the context clearly indicates otherwise.

   1. (1) Accessible surface--The external surface of the enclosure or housing provided by the manufacturer.
   2. (2) Aluminum equivalent--The thickness of type 1100 aluminum alloy affording the same attenuation, under specified conditions, as the material in question. The nominal chemical composition of type 1100 aluminum alloy is 99% minimum aluminum, 0.12% copper.
   3. (3) Applicator--A structure that determines the extent of the treatment field at a given distance from the virtual source.
   4. (4) Attenuation block--A block or stack, having dimensions 20 centimeters (cm) by 20 cm by 3.8 cm, of type 1100 aluminum alloy or other materials having equivalent attenuation. The nominal chemical composition of type 1100 aluminum alloy is 99% minimum aluminum, 0.12% copper.
   5. (5) Automatic exposure control (AEC)--A device that automatically controls one or more technique factors in order to obtain a required quantity of radiation at preselected locations (See definition for phototimer).
   6. (6) Automatic exposure rate control (AERC)--A device that automatically controls one or more technique factors in order to obtain a required quantity of radiation per unit time at preselected locations.
   7. (7) Barrier--(See definition for protective barrier).
   8. (8) Beam axis--A line from the source through the centers of the x-ray fields.
   9. (9) Beam indicating device--A device on dental x-ray equipment used to indicate the beam position and to establish a definite source-surface (skin) distance. It may or may not incorporate or serve as a beam-limiting device.
   10. (10) Beam quality (diagnostic x-ray)--A term that describes the penetrating power of the x-ray beam. This is identified numerically by half-value layer and is influenced by kVp and filtration.
   11. (11) Beam quality (therapy)--A term that describes the type and quality of ionizing radiation produced by a therapy system for certain machine settings.
   12. (12) Beam-limiting device--A device that provides a means to restrict the dimensions of the x-ray field.
   13. (13) Beam monitoring system--A system designed to detect and measure the radiation present in the useful beam.
   14. (14) Beam scattering foil--A foil used in order to scatter a beam of electrons.
   15. (15) Block tray--A device attached to the radiation head to support auxiliary beam blocking material.
   16. (16) Bone densitometer--A device intended for medical purposes to measure bone density and mineral content by x-ray transmission measurements through the bone and adjacent tissues.
   17. (17) Calibration of instruments--The comparative response or reading of an instrument relative to a series of known radiation values over the range of the instrument.
   18. (18) Calibration of machines--The measurement and specification of absorbed dose to a medium, or exposure in air, at a defined point in a radiation beam.
   19. (19) Central axis of the beam--A line passing through the virtual source and the center of the plane figure formed by the edge of the first beam-limiting device.
   20. (20) Certified equipment--Equipment that has been certified in accordance with 21 Code of Federal Regulations (CFR).
   21. (21) Coefficient of variation or C--The ratio of the standard deviation to the mean value of a population of observations. It is estimated using the following equation:

5. (e) General requirements for chiropractic, dental, medical, podiatric, and veterinary facilities.

   1. (1) Technique chart. A technique chart relevant to the particular x-ray unit shall be provided or electronically displayed in the vicinity of the control panel and used by all operators.
   2. (2) Operating and safety procedures. Each registrant shall have and implement written operating and safety procedures. These procedures shall be made available to each individual operating x-ray equipment, including any restrictions of the operating technique required for the safe operation of the particular x-ray system. These procedures shall include, but are not limited to, the items in subsection (cc)(3) of this section.
   3. (3) Occupational dose limitation and personnel monitoring. Except as otherwise exempted, all individuals who are associated with the operation of a radiation machine are subject to the radiation dose limits of §289.202(f), (j), and (l)-(m) of this title regarding dose limits to individuals, and the personnel monitoring requirements of §289.202(q) of this title.

   4. (4) Protective devices. Protective devices shall be utilized when required, as in subsection (i)(3) of this section, subsections (j)(2), (k)(5)(B), (r)(7), and (x)(4)(D)(iii) of this section.

      1. (A) Protective devices shall be made of no less than 0.25 millimeter (mm) lead equivalent material.
      2. (B) Protective devices, including aprons, gloves, and shields shall be checked annually for defects, such as holes, cracks, and tears. These checks may be performed by the registrant by visual, tactile, or x-ray imaging. If such defect is found, equipment shall be replaced or removed from service until repaired. A record of this test shall be made and maintained by the registrant in accordance with subsection (cc)(2) of this section for inspection by the agency.

   5. (5) Records.

      1. (A) The registrant shall maintain the following records for each radiation machine in accordance with subsection (cc)(2) of this section for inspection by the agency:

         1. (i) records of receipt;
         2. (ii) transfer;
         3. (iii) disposal;
         4. (iv) surveys;
         5. (v) calibrations;
         6. (vi) maintenance;
         7. (vii) equipment performance evaluation tests; and
         8. (viii) modifications performed on the radiation machine after April 1, 1989.

      2. (B) Records required in subparagraph (A) of this paragraph may be maintained in electronic format and shall include the following:

         1. (i) manufacturer name, model number, and serial number from the control panel or console of the radiation machine;
         2. (ii) dates of receipt, transfer, and disposal; and
         3. (iii) name of the individual recording the information.
   6. (6) Operator credentialing. Individuals who operate radiation machines shall meet the appropriate credentialing requirements of rules issued in accordance with the Medical Radiologic Technologist Act, Texas Civil Statutes, Article 4512m. Copies of the credentialing document shall be maintained at the locations(s) where the individual is working.
   7. (7) Practice of Medical Physics. Surveys, tests, or evaluations required by this section may constitute the practice of medical physics and, therefore, require a license from the Texas Board of Licensure for Professional Medical Physicists in accordance with the Medical Physics Practice Act, Texas Civil Statutes, Article 4512n.

6. (f) Healing arts screening and medical research.

   1. (1) Any person proposing to conduct a healing arts screening program for humans shall not initiate such a program without prior approval of the agency. When requesting such approval, that person shall submit the information outlined in subsection (cc)(1) of this section. If any information submitted to the agency becomes invalid or outdated, the agency shall be notified within 15 days.
   2. (2) Any research using radiation producing devices on humans must be approved by an IRB as required by 45 CFR 46 and 21 CFR 56. The IRB must include at least one practitioner of the healing arts to direct any use of radiation in accordance with §289.201(a) of this title.
7. (g) Educational facilities. Facilities conducting training using non-humans are held to all the requirements of this section except for subsection (e)(6) of this section concerning operator credentialing, subsection (h) of this section concerning radiographic entrance exposure limits, subsections (l)-(m) of this section concerning film processing, and subsection (q) of this section concerning equipment performance evaluation.
8. (h) Radiographic entrance exposure limits for chiropractic, dental, medical, and podiatric facilities. This does not apply to veterinary facilities. The in-air exposure determined for the technique used for the specified average human adult patient thickness for routine medical radiography shall not exceed the entrance exposure limits in the following Table I:

9. (i) Additional operational requirements for medical, podiatric, and chiropractic facilities.

   1. (1) Viewing system. Windows, mirrors, closed circuit television, or an equivalent system shall be provided to permit the operator to continuously observe the patient during irradiation. The operator shall be able to maintain verbal, visual, and aural contact with the patient.
   2. (2) Operator position. The operator's position during the exposure shall be such that the operator exposure is as low as reasonably achievable (ALARA) and/or protected by an apron, gloves, or other shielding having a minimum of 0.25 mm lead equivalent material.

   3. (3) Exposure of individuals other than the patient. Except for patients who cannot be moved out of the room (e.g., critical care areas, emergency rooms, or trauma units), only the staff and ancillary personnel required for the medical procedure or training shall be in the room during the radiation exposure.

      1. (A) All individuals, other than the patient being examined, shall be positioned so that exposure is ALARA and/or protected by an apron, gloves, or other shielding having a minimum of 0.25 millimeter (mm) lead equivalent material.
      2. (B) Notwithstanding the provisions of subparagraph (A) of this paragraph, other patients who are in line with the primary beam and who cannot be removed from the room, shall be protected by whole body protective barriers of a minimum of 0.25 mm lead equivalent material or so positioned that the nearest portion of their body is at least six feet from both the tube head and the nearest edge of the image receptor.
   4. (4) Gonadal shielding. Gonadal shielding shall be used on patients when the gonads are in or within 5 cm of the useful beam. This requirement does not apply if the shielding will interfere with the diagnostic procedure. Gonadal shielding shall be of at least 0.5 mm lead equivalent material.

   5. (5) Holding of patient or film. When a patient or film must be provided with auxiliary support during a radiation exposure the following shall apply.

      1. (A) Mechanical holding devices shall be used when the technique permits. The written operating and safety procedures required by subsection (e)(2) of this section shall list circumstances in which mechanical holding devices cannot be routinely utilized.
      2. (B) The requirements for selecting an individual who holds or supports the patient, and the procedure that the holder shall follow, shall be included in the written safety procedures as required by subsection (e)(2) of this section.
      3. (C) The human holder shall be protected, as required by subparagraph (A) of this paragraph.
      4. (D) In no case shall an individual hold the x-ray tube housing during any radiographic exposure.
      5. (E) In those cases where the patient must hold the film, any portion of the body other than the area of clinical interest struck by the useful beam shall be protected by not less than 0.25 mm lead equivalent material.

10. (j) Additional operational controls for dental radiographic systems.

    1. (1) Film holding devices shall be used except in individual cases in which the practitioner has determined that such holding devices are contraindicated. Written operating and safety procedures required by subsection (e)(2) of this section shall state the criteria under which the exception may apply.
    2. (2) The operator shall stand at least six feet from the useful beam or behind a protective barrier. The operator shall maintain verbal, aural, and visual contact with the patient.
    3. (3) The tube housing support shall be constructed and adjusted so that the tube housing shall not drift from its set position during an exposure. Neither the tube housing nor support housing shall be hand-held during an exposure.

11. (k) Additional operational controls for veterinary x-ray systems.

    1. (1) All exams and retakes shall be ordered by the veterinarian.
    2. (2) In no case shall an individual hold the x-ray tube during any radiographic exposure.
    3. (3) The operator's position during the exposure shall be such that the operator exposure shall be as low as reasonably achievable (ALARA) and/or protected by an apron, gloves, or other shielding having a minimum of 0.25 mm lead equivalent material.
    4. (4) No individual, other than the operator, shall be in the x-ray room or area while exposures are being made unless such individual's assistance is required.

    5. (5) When an animal must be held in position during radiography, mechanical supporting or restraining devices shall be used when technique permits.

       1. (A) A pregnant member of the public shall not hold or restrain an animal.
       2. (B) If the animal must be held by an individual, that individual shall be protected with appropriate shielding devices, such as protective gloves and apron, in accordance with subsection (e)(4) of this section and the person shall be so positioned that no part of his/her body except hands and arms will be struck by the useful beam.

12. (l) Automatic and manual film processing for chiropractic, dental, medical, podiatric, and veterinary facilities and mobile services.

    1. (1) Films shall be developed in accordance with the time-temperature relationships recommended by the film manufacturer. The specified developer temperature for automatic processing and the time-temperature chart for manual processing shall be posted in the darkroom.
    2. (2) Chemicals shall be replaced according to the chemical manufacturer's or supplier's recommendations or at an interval not to exceed three months.
    3. (3) Darkroom light leak tests shall be performed and any light leaks corrected at intervals not to exceed six months.
    4. (4) Lighting in the film processing/loading area shall be maintained with the filter, bulb wattage, and distances recommended by the film manufacturer for that film emulsion or with products that provide an equivalent level of protection against fogging.
    5. (5) Corrections or repairs of the light leaks or related deficiencies in paragraphs (3) and (4) of this subsection shall be initiated within 72 hours of discovery and completed no longer than 15 days from detection of the deficiency unless a longer time is authorized by the agency. Records of the correction or repairs shall include the date and initials of the individual performing these functions and shall be maintained in accordance with subsection (cc)(2) of this section for inspection by the agency.
    6. (6) Documentation of the items in paragraphs (2), (3), and (5) of this subsection shall be maintained at the site where performed and shall include the date and initials of the individual completing these items. These records shall be kept in accordance with subsection (cc)(2) of this section for inspection by the agency.
13. (m) Alternative processing systems. Users of daylight processing systems, laser processors, self-processing film units, or other alternative processing systems shall follow manufacturer's recommendations for image processing.

14. (n) Record requirements for mobile services and authorized use locations for chiropractic, dental, medical, podiatric, and veterinary facilities.

    1. (1) Copies of the following records shall be kept with units authorized for mobile service:

       1. (A) operating and safety procedures in accordance with subsection (e)(2) of this section;
       2. (B) credentials of operators of radiation machines operating at that location in accordance with subsection (e)(6) of this section;
       3. (C) current §289.112 of this title, §289.114 of this title, §289.201 of this title, §289.202 of this title, §289.226 of this title, and §289.227 of this title;
       4. (D) certificate of registration;
       5. (E) current film processing records for at least 90 days for on-board processors in accordance with subsection (l)(2), (3), and (5) of this section, as applicable;
       6. (F) documentation of completion of equipment performance evaluation and corrective actions in accordance with subsection (q) of this section; and
       7. (G) notice of violation from last inspection, if applicable, and documentation of corrections of any violations.

    2. (2) Copies of the following records for mobile services shall be maintained at the authorized records location:

       1. (A) current §289.112 of this title, §289.114 of this title, §289.201 of this title, §289.202 of this title, §289.204 of this title, §289.226 of this title, and §289.227 of this title;
       2. (B) certificate of registration;
       3. (C) surveys of radiation levels in unrestricted areas in accordance with §289.202(n) of this title;
       4. (D) personnel monitoring records of occupationally exposed individuals in accordance with §289.202(f), (j), or (m) of this title, as applicable;
       5. (E) documentation of annual check of protective devices in accordance with subsection (e)(4)(B) of this section;
       6. (F) records of receipt, transfer, and disposal and surveys, calibrations, maintenance, equipment performance evaluations, and modifications of radiation machines in accordance with subsection (e)(5) of this section;
       7. (G) film processing records for that location and all on-board processors in accordance with subsection (l)(2), (3), and (5) of this section, as applicable (excluding the records that are maintained on-board with the mobile service);
       8. (H) United States Food and Drug Administration (FDA) variances in accordance with subsection (p) of this section;
       9. (I) current annual survey of fluoroscopic x-ray machines being operated on-board in accordance with subsection (r)(3)(D) of this section; and
       10. (J) CT dose measurements and CT quality control films or images in accordance with subsection (v)(3)(A) and (v)(4)(B) of this section.

    3. (3) Copies of the following records shall be maintained at authorized use locations:

       1. (A) current §289.112 of this title, §289.114 of this title, §289.201 of this title, §289.202 of this title, §289.204 of this title, §289.226 of this title, and §289.227 of this title;
       2. (B) certificate of registration;
       3. (C) surveys of radiation levels in unrestricted areas in accordance with §289.202(n) of this title;
       4. (D) personnel monitoring records of occupationally exposed individuals in accordance with §289.202(f), (j), or (m) of this title, as applicable;
       5. (E) operating and safety procedures in accordance with subsection (e)(2) of this section;
       6. (F) documentation of annual check of protective devices at that location in accordance with subsection (e)(4)(B) of this section;
       7. (G) records of receipt, transfer, and disposal and surveys, calibrations, maintenance, equipment performance evaluation, and modification of radiation machines at that location in accordance with subsection (e)(5) of this section;
       8. (H) credentials of operators of radiation machines operating at that location in accordance with subsection (e)(6) of this section;
       9. (I) film processing records for that location in accordance with subsection (l)(2), (3), and (5) of this section, as applicable;
       10. (J) FDA variances of machines at that location in accordance with subsection (p) of this section;
       11. (K) current annual survey of fluoroscopic x-ray machines being operated at that location in accordance with subsection (r)(3)(D) of this section;
       12. (L) CT dose measurements and CT quality control films or images at that location in accordance with subsection (v)(3)(A) and (v)(4)(B) of this section;
       13. (M) therapy (under 500 kV) surveys and calibrations of equipment at that location in accordance with subsection (x)(4)(A)(i) and (ii) and (B)(v) of this section;
       14. (N) therapy (above 500 kV) surveys and calibrations of equipment at that location in accordance with subsection (y)(3)(C)(vi) and (D)(vii) of this section;
       15. (O) records, notices, and reports of therapy misadministrations in accordance with subsection (bb)(2) of this section; and
       16. (P) notice of violation from last inspection, if applicable, and documentation of corrections of any violations.

15. (o) General requirements for all diagnostic x-ray systems for chiropractic, dental, medical, podiatric, and veterinary facilities.

    1. (1) Warning label. The warning label will meet the requirements of §289.202(cc)(3) of this title.
    2. (2) Mechanical support of tube head. The tube housing assembly shall be adjusted to remain stable during an exposure unless tube housing movement is a designed function of the x-ray system. The tube housing assembly supports shall not be hand-held.
    3. (3) Battery charge indicator. On battery-powered x-ray 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.
    4. (4) Radiation from components other than the diagnostic source assembly. The radiation emitted by a component other than the diagnostic source assembly shall not exceed 2 mR in one 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. Measurement is averaged over an area of 100 square centimeter (cm[sup]2[/sup]) with no linear dimension greater than 20 cm.

    5. (5) Beam quality. The following requirements apply to beam quality.

       1. (A) Half-value layer.

          1. (i) The half-value layer of the useful beam for a given x-ray tube potential shall not be less than the values shown in the following Table II. If it is necessary to determine such half-value layer at an x-ray tube potential that is not listed in Table II, linear interpolation may be made.
16. (p) Certified equipment for chiropractic, medical, dental, and podiatric facilities. This subsection does not apply to veterinary facilities. In addition to the requirements of this chapter, the registrant shall not make, nor cause to be made, any modification of components or installations of components certified in accordance with the United States Food and Drug Administration (FDA) 21 CFR 1020, "Performance Standards for Ionizing Radiation Emitting Products," as amended in any manner that could cause the installations or the components to fail to meet the requirements of the applicable parts of the standards specified in 21 CFR 1020, except where a variance has been granted by the Director, Center for Devices and Radiological Health, FDA. A copy of the variance shall be maintained by the registrant in accordance with subsection (cc)(2) of this section for inspection by the agency.

17. (q) Equipment performance evaluation for chiropractic, medical, dental, and podiatric facilities. This subsection does not apply to veterinary facilities.

    1. (1) For all x-ray systems listed in paragraphs (3)-(6) of this subsection, the registrant shall perform, or cause to be performed, tests necessary to assure proper function of equipment with the indicated standard for each item specified. Such tests shall be performed at the frequency listed in subsection (cc)(4) of this section.

    2. (2) Any items not meeting the specifications of the tests shall be corrected or repaired.

       1. (A) Correction or repair shall begin within 30 days following the check and shall be performed according to a plan designated by the registrant. Correction or repair shall be completed no longer than 90 days from discovery unless authorized by the agency.
       2. (B) Records of the test results, including any numerical readings, and any corrections or repairs shall be maintained by the registrant in accordance with subsection (cc)(2) of this section for inspection by the agency.

    3. (3) Radiographic x-ray equipment performance evaluation.

       1. (A) Timer. The accuracy of the timer shall meet the manufacturer's specifications. If the manufacturer's specifications are not obtainable, the timer accuracy shall be plus or minus 10% of the indicated time with testing performed at 0.5 second.
       2. (B) Exposure reproducibility. Exposure reproducibility shall meet the requirements of subsection (s)(4) of this section.
       3. (C) Linearity. mR/mAs stations shall meet the requirements of subsection (s)(5) of this section.
       4. (D) kVp. If the registrant possesses documentation of the appropriate manufacturer's kVp specifications, the unit shall meet those specifications. If the registrant does not possess documentation of the appropriate manufacturer's kVp specifications, the indicated kVp shall be accurate to within plus or minus 10% of the indicated setting at no less than three points over the usual operating range of the machine.
       5. (E) Tube stability. The x-ray tube shall remain physically stable during exposures. In cases where tubes are designed to move during exposure, the registrant shall assure proper and free movement of the unit.

       6. (F) Collimation. The following items shall meet the requirements of subsection (s)(1) of this section:

          1. (i) numerical indicators of x-ray field size;
          2. (ii) light field versus x-ray field congruence;
          3. (iii) automatic and semi-automatic collimators unless disabled; and
          4. (iv) center of x-ray field alignment with center of image receptor.
    4. (4) Fluoroscopic x-ray systems and spot film devices equipment performance evaluation. Fluoroscopic equipment shall meet the requirements of subsection (r) of this section.

    5. (5) Dental x-ray systems equipment performance evaluation.

       1. (A) Timer. The accuracy of the timer shall meet the manufacturer's specifications. If the manufacturer's specifications are not obtainable, the timer accuracy shall be plus or minus 10% of the indicated time with testing performed at 0.5 second.
       2. (B) Exposure reproducibility. Exposure reproducibility shall meet the requirements of subsection (t)(1)(D) of this section.
       3. (C) kVp. If the registrant possesses documentation of the appropriate manufacturer's kVp specifications, the unit shall meet those specifications. If the registrant does not possess documentation of the appropriate manufacturer's kVp specifications, the indicated kVp shall be accurate to within plus or minus 10% of the indicated setting at no less than three points over the usual operable range of the machine. For units with fewer than three fixed kVp settings, the unit shall be checked at those settings.
       4. (D) Tube stability. The x-ray tube shall remain physically stable during exposures. In cases where tubes are designed to move during exposure, the registrant shall assure proper and free movement of the unit.
       5. (E) Collimation. Field limitation shall meet the requirements of subsection (t)(3) of this section.
    6. (6) CT x-ray systems equipment performance evaluation. CT x-ray systems shall meet the requirements of subsection (v) of this section.

18. (r) Fluoroscopic x-ray systems and spot-film devices for all facilities.

    1. (1) Limitation of the useful beam shall be as follows.

       1. (A) Primary barrier.

          1. (i) The fluoroscopic imaging assembly shall be provided with a primary protective barrier that intercepts the entire cross section of the useful beam at any SID.
          2. (ii) The x-ray tube used for fluoroscopy shall not produce x-rays unless the barrier is in position to intercept the useful beam and the imaging device is in place and operable.
          3. (iii) The exposure rate due to transmission through the barrier with the attenuation block in the useful beam, combined with radiation through the image intensifier if provided, shall not exceed 3.34 x 10[sup]-3[/sup]% of the entrance exposure rate at a distance of 10 cm from any accessible surface of the fluoroscopic imaging assembly beyond the plane of the image receptor.

       2. (B) Measuring compliance of barrier transmission.

          1. (i) The exposure rate due to transmission through the primary protective barrier combined with radiation through the image intensifier shall be determined by measurements averaged over an area of 100 cm[sup]2[/sup] with no linear dimension greater than 20 cm.
          2. (ii) If the source is below the tabletop, the measurement shall be made with the input surface of the fluoroscopic imaging assembly positioned 30 cm above the tabletop.
          3. (iii) If the source is above the tabletop and the SID is variable, the measurement shall be made with the end of the beam-limiting device or spacer as close to the tabletop as it can be placed, provided that it shall not be closer than 30 cm.
          4. (iv) Movable grids and compression devices shall be removed from the useful beam during the measurement.
          5. (v) The attenuation block shall be positioned in the useful beam 10 cm from the point of measurement of entrance exposure rate and between this point and the input surface of the fluoroscopic imaging assembly.
          6. (vi) The collimator shall be fully open when the measurement is made.

       3. (C) X-ray field.

          1. (i) Equipment with a fixed SID and the capability of a visible area of no greater than 300 cm[sup]2[/sup] shall be provided with either stepless adjustment of the x-ray field or a means to further limit the x-ray field at the image receptor to 125 cm[sup]2[/sup] or less. If the equipment is provided with stepless adjustment, the minimum x-ray field size at the maximum SID shall be less than or equal to 5 cm by 5 cm at the image receptor.
          2. (ii) Equipment with a variable SID or a fixed SID with the capability of a visible area of greater than 300 cm[sup]2[/sup] shall be provided with stepless adjustment of the field size. The minimum x-ray field size at the maximum SID shall be less than or equal to 5 cm by 5 cm at the image receptor.
          3. (iii) Neither the length nor the width of the x-ray field in the plane of the image receptor shall exceed that of the visible area of the image receptor by more than 3.0% of the SID. The sum of the excess length and the excess width shall be no greater than 4.0% of the SID.
          4. (iv) For rectangular x-ray fields used with circular image receptors, the error in alignment shall be determined along the length and width dimensions of the x-ray field that pass through the center of the visible area of the image receptor.
          5. (v) For fluoroscopic equipment with only a manual mode of collimation, the x-ray field produced shall be limited to the area of the spot-film cassette at 16 inches above tabletop. Additionally, during fluoroscopy, the beam shall be restricted to the area of the input phosphor.

          6. (vi) Spot-film devices shall meet the following additional requirements.

             1. (I) Means shall be provided between the source and the patient for adjustment of the x-ray field size in the plane of the film to the size of that portion of the film that has been selected on the spot-film selector.

                (-a-) Such adjustment shall be automatically accomplished except when the x-ray field size in the plane of the film is smaller than that of the selected portion of the film.

                (-b-) The total misalignment of the edges of the x-ray field with the respective edges of the selected portion of the image receptor along the length or width dimensions of the x-ray field in the plane of the image receptor shall not exceed 3.0% of the SID when adjusted for full coverage of the selected portion of the image receptor.

                (-c-) The sum, without regard to sign of the misalignment along any two orthogonal dimensions, shall not exceed 4.0% of the SID.

             2. (II) The center of the x-ray field in the plane of the film shall be aligned with the center of the selected portion of the film to within 2.0% of the SID.
          7. (vii) Compliance with subparagraph (B) of this paragraph shall be determined with the beam axis perpendicular to the plane of the image receptor.
    2. (2) Activation of the fluoroscopic tube. X-ray production in the fluoroscopic mode shall be controlled by a device that requires continuous pressure by the fluoroscopist for the entire time of the exposure (continuous pressure type switch). When recording serial fluoroscopic images, the fluoroscopist shall be able to terminate the x-ray exposures at any time, but means may be provided to permit completion of any single exposure of the series in process.

    3. (3) Entrance exposure rate allowable limits.

       1. (A) The following requirements apply to fluoroscopic equipment manufactured prior to May 19, 1995.

          1. (i) Equipment with automatic exposure rate control (AERC). Fluoroscopic equipment that is provided with AERC shall not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 2.58 x 10[sup]-3[/sup] coulomb per kilogram per minute (C/kg/min) (10 roentgens per minute (10 R/min)) at the point where the center of the useful beam enters the patient, except:

             1. (I) during recording of fluoroscopic images; or
             2. (II) when an optional high-level control is provided. When so provided, the equipment shall not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 1.29 x 10[sup]-3[/sup] C/kg/min (5 R/min) at the point where the center of the useful beam enters the patient, unless the high-level control is activated. Special means of activation of high-level controls shall be required. The high-level control shall be operable only when continuous manual activation is provided by the operator. A continuous signal audible to the fluoroscopist shall indicate that the high-level control is being employed.

          2. (ii) Equipment without AERC (manual mode). Fluoroscopic equipment that is not provided with AERC shall not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 1.29 x 10[sup]-3[/sup] C/kg/min (5 R/min) at the point where the center of the useful beam enters the patient, except:

             1. (I) during recording of fluoroscopic images; or
             2. (II) when an optional high-level control is activated. Special means of activation of high-level controls shall be required. The high-level control shall be operable only when continuous manual activation is provided by the operator. A continuous signal audible to the fluoroscopist shall indicate that the high-level control is being employed.

          3. (iii) Equipment with both an AERC mode and a manual mode. Fluoroscopic equipment that is provided with both an AERC mode and a manual mode shall not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 2.58 x 10[sup]-3[/sup] C/kg/min (10 R/min) in either mode at the point where the center of the useful beam enters the patient except:

             1. (I) during recording of fluoroscopic images; or
             2. (II) when the mode or modes have an optional high-level control, in which case that mode or modes shall not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 1.29 x 10[sup]-3[/sup] C/kg/min (5 R/min) at the point where the center of the useful beam enters the patient, unless the high level control is activated. Special means of activation of high-level control shall be required. The high level control shall be operable only when continuous manual activation is provided by the operator. A continuous signal audible to the fluoroscopist shall indicate that the high-level is being employed.

          4. (iv) Measuring compliance. Compliance with subparagraph (A) of this paragraph shall be determined as follows.

             1. (I) If the source is below the x-ray table, the exposure rate shall be measured at 1 cm above the tabletop or cradle.
             2. (II) If the source is above the x-ray table, the exposure rate shall be measured at 30 cm above the tabletop with the end of the beam-limiting device or spacer positioned as closely as possible to the point of measurement.
             3. (III) In a C-arm type of fluoroscope, the exposure rate shall be measured at 30 cm from the input surface of the fluoroscopic imaging assembly provided that the end of the beam-limiting device or spacer is no closer than 30 cm from the input surface of the fluoroscopic imaging assembly. The applicable limit shall not be exceeded at any available SID.
             4. (IV) In a lateral (horizontal) type of fluoroscope, the exposure rate shall be measured at a point 15 cm from the centerline of the x-ray table and in the direction of the x-ray source with the end of the beam-limiting device or spacer positioned as closely as possible to the point of measurement. If the table top is movable, it shall be positioned as closely as possible to the lateral x-ray source, with the end of the beam-limiting device or spacer no closer than 15 cm to the centerline of the x-ray table.

       2. (B) Entrance exposure rate limits. The following requirements apply to fluoroscopic equipment manufactured on and after May 19, 1995.

          1. (i) Fluoroscopic equipment operable at any combination of tube potential and current that will result in an exposure rate greater than 1.29 x 10[sup]-3[/sup] C/kg/min (5 R/min) at the point where the center of the useful beam enters the patient shall be equipped with AERC. Provision for manual selection of technique factors may be provided.

          2. (ii) Fluoroscopic equipment shall not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 2.58 x 10[sup]-3[/sup] C/kg/min (10 R/min) at the point where the center of the useful beam enters the patient except:

             1. (I) During the recording of images from an x-ray image-intensifier tube using photographic film or a video camera when the x-ray source is operated in a pulsed mode.
             2. (II) When the high-level control is activated, the equipment shall not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 5.16 x 10[sup]-3[/sup] C/kg/min (20 R/min) at the point where the center of the useful beam enters the patient. Special means of activation of high-level controls shall be required. The high-level control shall only be operable when continuous manual activation is provided by the operator. A continuous signal audible to the fluoroscopist shall indicate that the high-level control is being employed.

          3. (iii) Measuring compliance. Compliance with subparagraph (B) of this paragraph shall be determined as follows.

             1. (I) If the source is below the x-ray table, the exposure rate shall be measured at 1 cm above the tabletop or cradle.
             2. (II) If the source is above the x-ray table, the exposure rate shall be measured at 30 cm above the tabletop with the end of the beam-limiting device or spacer positioned as closely as possible to the point of measurement.
             3. (III) In a C-arm type of fluoroscope, the exposure rate shall be measured at 30 cm from the input surface of the fluoroscopic imaging assembly provided that the end of the beam-limiting device or spacer is no closer than 30 cm from the input surface of the fluoroscopic imaging assembly. The applicable limit shall not be exceeded at any available SID.
             4. (IV) In a lateral (horizontal) type of fluoroscope, the exposure rate shall be measured at a point 15 cm from the centerline of the x-ray table and in the direction of the x-ray source with the end of the beam-limiting device or spacer positioned as closely as possible to the point of measurement. If the table top is movable, it shall be positioned as closely as possible to the lateral x-ray source, with the end of the beam-limiting device or spacer no closer than 15 cm to the centerline of the x-ray table.
       3. (C) Hand-held fluoroscopes. For hand-held fluoroscopes, the exposure rate shall be measured at the point closest to the source.

       4. (D) Periodic measurement of entrance exposure rate. Periodic measurement of entrance exposure rate shall be performed by a licensed medical physicist with a specialty in diagnostic radiological physics as follows.

          1. (i) Such measurements shall be made within 30 days of installation, annually, and within 30 days after any maintenance of the system that might affect the exposure rate.
          2. (ii) Results of these measurements shall be posted where any fluoroscopist may have ready access to such results while using the fluoroscope and retained as required in subsections (e)(5) and (cc)(2) of this section. The measurement results shall be stated in R/min and include the technique factors used in determining such results. The name of the person performing the measurements and the date the measurements were performed shall be included in the results.

          3. (iii) Conditions of periodic measurement of entrance exposure rate are as follows.

             1. (I) The measurement shall be made in accordance with subparagraph (A)(iv) or (B)(iii) of this paragraph, as applicable.
             2. (II) X-ray systems that do not incorporate an AERC shall utilize a milliamperage and kVp typical of the clinical use of the x-ray system. Materials should be placed in the useful beam between the detection and imaging systems when conducting these periodic measurements to protect the imaging system.
             3. (III) X-ray systems that do incorporate an AERC shall have sufficient material placed in the useful beam to produce a milliamperage and kVp typical of the clinical use of the x-ray system.
    4. (4) Indication of potential and current. During fluoroscopy and cinefluorography, the kV and the mA shall be continuously indicated at the control panel and/or the fluoroscopist's position.

    5. (5) SSD. The SSD shall not be less than the following:

       1. (A) 38 cm on stationary fluoroscopes installed after March 1, 1989;
       2. (B) 35.5 cm on stationary fluoroscopes that were in operation prior to March 1, 1989;
       3. (C) 30 cm on all mobile and portable fluoroscopes;
       4. (D) 20 cm for image-intensified fluoroscopes used for examinations as specified in the registrant's operating and safety procedures. The written operating and safety procedures shall provide precautionary measures to be adhered to during the use of this device. The procedures must provide information on the means to restore the unit to a 30 cm SSD when the unit is returned to general service; and
       5. (E) the FDA approved variance for a specific manufacturer of a hand-held fluoroscope.

    6. (6) Fluoroscopic timer.

       1. (A) Means shall be provided to preset the cumulative on-time of the fluoroscopic x-ray tube. The maximum cumulative time of the timing device shall not exceed five minutes without resetting.
       2. (B) A signal audible to the fluoroscopist shall indicate the completion of any preset cumulative on-time. Such signal shall continue to sound while x-rays are produced until the timing device is reset. In lieu of such signal, the timer shall terminate the beam after the preset cumulative on-time is completed.

    7. (7) Control of scattered radiation.

       1. (A) Fluoroscopic configuration, including fluoroscopic table designs, shall not permit any portion of any individual's body, except the head, neck, and extremities, to be exposed to scattered radiation emanating from above or below the tabletop unless the radiation has passed through not less than a total of 0.25 mm lead equivalent material. The material may be, but is not limited to, drapes, self-supporting curtains, or viewing shields, in addition to any lead equivalency provided by a protective apron.

       2. (B) Where sterile fields or special procedures prohibit the use of normal protective barriers or drapes, all of the following conditions shall be met.

          1. (i) All persons, except the patient, in the room where fluoroscopy is performed, shall wear protective aprons that provide a shielding equivalent of 0.5 mm of lead.
          2. (ii) The fluoroscopic field size shall be reduced to the absolute minimum required for the procedure being performed (area of clinical interest).
          3. (iii) Operating and safety procedures shall reflect the above conditions, and fluoroscopy personnel shall exhibit awareness of situations requiring the use and/or nonuse of the protective drapes.
       3. (C) For image-intensified fluoroscopic equipment with only a manual mode of collimation, the x-ray field produced shall be limited to the area of the spot-film cassette at 16 inches above tabletop. Additionally, during fluoroscopy, the beam shall be restricted to the area of the input phosphor.

19. (s) Additional technical standards for chiropractic, medical, and podiatric facilities. This subsection does not apply to fluoroscopic, dental, veterinary, or computed tomography systems.

    1. (1) Beam limitation shall be as follows.

       1. (A) Stationary general purpose and mobile x-ray systems.

          1. (i) Beam limiting devices shall restrict the useful beam to the area of clinical interest. The x-ray field shall not exceed any one of the following:

             1. (I) 2.0% of the SID for the length or width of the image receptor for manual rectangular collimation;
             2. (II) 2.0% of the SID for the diagonal of the image receptor for circular or polygon collimation; or
             3. (III) 3.0% of the SID for the length or width or if the sum of the length and width difference, without regard to sign, exceed 4.0% of the SID for automatic or semi-automatic collimation.
          2. (ii) 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 2.0% 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.
          3. (iii) An SID indicator shall be present and shall be accurate to within 2.0% of the SID.

       2. (B) Additional requirements for stationary general purpose x-ray systems are as follows.

          1. (i) A method shall be provided to indicate when 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 2.0% of the SID and to indicate the SID to within 2.0%.
          2. (ii) The beam-limiting device shall indicate numerically the field size in the plane of the image receptor, to which it is adjusted.
          3. (iii) Indication of field size dimensions and SIDs shall be specified in inches and/or centimeters, and shall be such that aperture adjustments result in x-ray field dimensions in the plane of the image receptor that correspond to those indicated by the beam-limiting device by no more than 2.0% of the SID when the beam axis is indicated to be perpendicular to the plane of the image receptor.
          4. (iv) An SID indicator shall be present and shall be accurate to within 2.0% of the actual SID.
       3. (C) X-ray systems designed for one image receptor size. Radiographic equipment designed for only one 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 2.0% of the SID, or shall be provided with means to both size and align the x-ray field such that the x-ray field at the plane of the image receptor does not extend beyond any edge of the image receptor.

       4. (D) Special purpose x-ray systems.

          1. (i) Means shall be provided to limit the x-ray field in the plane of the image receptor so that such field does not exceed each dimension of the image receptor by more than 2.0% of the SID when the axis of the x-ray beam is perpendicular to the plane of the image receptor.
          2. (ii) Means shall be provided to align the center of the x-ray field with the center of the image receptor to within 2.0% of the SID, or means shall be provided to both size and align the x-ray field such that the x-ray field at the plane of the image receptor does not extend beyond any edge of the image receptor.

          3. (iii) Clause (i) and (ii) of this subparagraph may be met with a system that meets the requirements for a general purpose x-ray system as specified in subparagraphs (A) or (B)(i) of this paragraph or, when alignment means are also provided, may be met with either of the following:

             1. (I) 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 such device having clear and permanent markings to indicate the image receptor size and SID for which it is designed; or
             2. (II) 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.

    2. (2) Radiation exposure control devices shall include the following:

       1. (A) X-ray control. An x-ray control shall be incorporated into each x-ray system such that an exposure can be terminated by the operator at any time except for an exposure of 0.5 second or less or during serial radiography when means shall be provided to permit completion of any single exposure of the series in process. The exposure switch shall be of the continuous pressure type.
       2. (B) Timers. Means shall be provided to terminate the exposure at a preset time interval, a preset product of current and time, a preset number of pulses, or a preset radiation exposure to the image receptor. In addition it shall not be possible to make an exposure when the timer is set to a "zero" or "off" position if either position is provided.

       3. (C) AEC. When an AEC is provided, the following shall occur:

          1. (i) indication shall be made on the control panel when this mode of operation is selected;
          2. (ii) if the x-ray tube potential is equal to or greater than 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 pulses;
          3. (iii) the minimum exposure time for all equipment other than that specified in clause (ii) of this subparagraph shall be equal to or less than 0.0167 second or a time interval required to deliver 5 mAs, whichever is greater;
          4. (iv) either the product of peak x-ray tube potential, current, and exposure time shall be limited to not more than 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 that, when the x-ray tube potential is less than 50 kVp, the product of x-ray tube current and exposure time shall be limited to not more than 2000 mAs per exposure; and
          5. (v) a visible and/or audible signal shall indicate when an exposure has been terminated at the limits required by clause (iv) of this subparagraph, and manual resetting shall be required before further automatically timed exposures can be made.
       4. (D) Exposure interval reproducibility. When all technique factors are held constant, including control panel selections associated with AEC systems, the coefficient of variation of exposure interval for both manual and AEC systems shall not exceed 0.05. This requirement applies to clinically used techniques.
    3. (3) SSD. All mobile or portable radiographic systems shall be provided with means to limit the SSD to equal to or greater than 30 cm.
    4. (4) Exposure reproducibility. When all technique factors are held constant, including control panel selections associated with AEC systems, the coefficient of variation of exposure for both manual and AEC systems shall not exceed 0.05. This requirement applies to clinically used techniques.
    5. (5) Linearity.

20. (t) Additional technical standards for dental facilities.

    1. (1) General requirements are as follows.

       1. (A) Timers. Means shall be provided to terminate the exposure at a preset time interval, a preset product of current and time, a preset number of pulses, or a preset radiation exposure to the image receptor. In addition, it shall not be possible to make an exposure when the timer is set to a "zero" or "off" position if either position is provided.
       2. (B) Exposure interval reproducibility. When all technique factors are held constant, including control panel selections associated with AEC systems, the coefficient of variation of exposure interval for both manual and AEC systems shall not exceed 0.05. This requirement applies to clinically used techniques.
       3. (C) X-ray control. An x-ray control shall be incorporated into each x-ray system such that an exposure can be terminated by the operator at any time, except for exposures of 0.5 second or less. Each x-ray control shall be located in such a way as to permit the operator to remain in an area of less than 2 mR in any one hour during the entire exposure. The exposure switch shall be of the continuous pressure type.
       4. (D) Exposure reproducibility. When all technique factors are held constant, including control panel selections associated with AEC systems, the coefficient of variation of exposure for both manual and AEC systems shall not exceed 0.05. This requirement applies to clinically used techniques.

    2. (2) Additional requirements for dental intraoral systems are as follows.

       1. (A) SSD. X-ray systems designed for use with an intraoral image receptor shall be provided with means to limit SSD to not less than:

          1. (i) 18 cm if operable above 50 kVp; or
          2. (ii) 10 cm if not operable above 50 kVp.

       2. (B) Field limitation. Radiographic systems designed for use with an intraoral image receptor shall be provided with means to limit the x-ray beam such that:

          1. (i) if the minimum SSD is 18 cm or more, the x-ray field at the minimum SSD shall be restricted to a dimension of no more than 7 cm; and
          2. (ii) if the minimum SSD is less than 18 cm, the x-ray field at the minimum SSD shall be restricted to a dimension of no more than 6 cm.

    3. (3) Additional requirements for dental extraoral systems are as follows.

       1. (A) Field limitation. Dental rotational panoramic systems shall be provided with means to restrict the x-ray beam to the imaging slit in the transverse axis and shall not exceed a total of 0.5 inches larger than the imaging slit in the vertical axis.

       2. (B) All other dental extraoral radiographic systems (e.g., cephalometric) shall be provided with means to restrict the x-ray field to the area of clinical interest. The restriction may not exceed the following:

          1. (i) 2.0% of the SID for the length or width of the image receptor for rectangular collimation; or
          2. (ii) 2.0% of the SID for the diagonal of the image receptor for circular or polygon collimation.

21. (u) Additional technical standards for veterinary x-ray facilities.

    1. (1) The x-ray control shall provide visual or audible indication of the production of x-rays observable at or from the operator's protected position whenever x-rays are produced.

    2. (2) Beam limiting devices shall provide the same degree of protection as is required of the housing and shall restrict the useful beam to the area of clinical interest. A method shall be provided so that the primary beam shall be centered with the film or image receptor. The restriction may not exceed the following:

       1. (A) 2.0% of the SID for the length or width of the image receptor for rectangular collimation; or
       2. (B) 2.0% of the SID for the diagonal of the image receptor for circular collimation.
    3. (3) Means shall be provided to terminate the exposure at a preset time interval, a preset product of current and time, a preset number of pulses, or a preset radiation exposure to the image receptor. In addition, it shall not be possible to make an exposure when the timer is set to a "zero" or "off" position if either position is provided.
    4. (4) A continuous pressure type exposure switch shall be provided, together with an exposure control cord of sufficient length, so that the operator can stand out of the useful beam and at least six feet from the animal during all x-ray exposures.
    5. (5) When all technique factors are held constant, including control panel selections associated with AEC systems, the coefficient of variation of exposure for both manual and AEC systems shall not exceed 0.05. This requirement applies to clinically used techniques.
    6. (6) The technique factors to be used during an exposure shall be indicated before the exposure begins. If AECs are used, the technique factors that are set prior to the exposure shall be indicated.
    7. (7) For machines having fixed technique factors, the requirements of paragraph (6) of this subsection may be met by permanent markings on the equipment. Indication of technique factors shall be visible from the operator's position except in the case of spot films made by the fluoroscopist.
    8. (8) Fluoroscopic, CT, and therapy systems used in veterinary facilities shall meet the requirements of subsections (r), (v), (x), and (y) of this section, except the aural communications requirements of subsections (v)(2)(A), (x)(2)(A), and (y)(2)(D) of this section.
    9. (9) Portable machines shall be used in a manner that complies with this section.

22. (v) CT x-ray systems.

    1. (1) Equipment requirements shall be as follows.

       1. (A) Tomographic plane indication and alignment.

          1. (i) For any single tomogram system, means shall be provided to permit visual determination of the tomographic plane or a reference plane offset from the tomographic plane.
          2. (ii) For any multiple tomogram system, means shall be provided to permit visual determination of the location of a reference plane. The reference plane can be offset from the location of the tomographic planes.
          3. (iii) If a device using a light source is used to satisfy the requirements of clause (i) or (ii) of this subparagraph, the light source shall provide illumination levels sufficient to permit visual determination of the location of the tomographic plane or reference plane under ambient light conditions of up to 500 lux.
       2. (B) Indication of CT conditions of operation. The CT x-ray system shall be designed such that the CT conditions of operation to be used during a scan or a scan sequence are indicated prior to the initiation of a scan or a scan sequence. On equipment having all or some of these conditions of operation at fixed values, this requirement may be met by permanent markings. Indication of CT conditions of operation shall be visible from any position from which scan initiation is possible.

       3. (C) Initiation of operation shall be as follows.

          1. (i) The x-ray control and gantry shall provide visual indication whenever x-rays are produced and, if applicable, whether the shutter is open or closed.
          2. (ii) Means shall be provided to require operator initiation of each individual scan or series of scans.
          3. (iii) All emergency buttons/switches shall be clearly labeled as to their functions.

       4. (D) Termination of exposure shall be as follows.

          1. (i) Means shall be provided to terminate the x-ray exposure automatically by either deenergizing the x-ray source or shuttering the x-ray beam in the event of equipment failure affecting data collection. Such termination shall occur within an interval that limits the total scan time to no more than 110% of its preset value through the use of either a backup timer or devices that monitor equipment function.
          2. (ii) A signal visible to the operator shall indicate when the x-ray exposure has been terminated through the means required by clause (i) of this subparagraph.
          3. (iii) The operator shall be able to terminate the x-ray exposure at any time during a scan or series of scans under CT x-ray system control, of greater than 0.5 second duration. Termination of the x-ray exposure shall necessitate resetting of the CT conditions of operation prior to initiation of another scan.

       5. (E) Additional requirements applicable to CT x-ray systems containing a gantry manufactured after September 3, 1985, are as follows.

          1. (i) The total error in the indicated location of the tomographic plane or reference plane shall not exceed 5 mm.
          2. (ii) If the x-ray production period is less than 0.5 second, the indication of x-ray production shall be actuated for at least 0.5 second. Indicators at or near the gantry shall be discernible from any point external to the patient opening where insertion of any part of the human body into the primary beam is possible.
          3. (iii) The deviation of indicated scan increment versus actual increment shall not exceed plus or minus 1 mm with any mass from 0 to 100 kilograms (kg) resting on the support device. The patient support device shall be incremented from a typical starting position to the maximum incremented distance or 30 cm, whichever is less, and then returned to the starting position. Measurement of actual versus indicated scan increment can be taken anywhere along this travel.

    2. (2) Facility design requirements shall include the following.

       1. (A) Provision shall be made for two-way aural communication between the patient and the operator at the control panel.
       2. (B) Windows, mirrors, closed-circuit television, or an equivalent shall be provided to permit continuous observation of the patient during irradiation and shall be so located that the operator can observe the patient from the control panel. When the primary viewing system is by electronic means, an alternate viewing system, which may be electronic, shall be available for use in the event of failure of the primary viewing system.

    3. (3) Dose measurements of the radiation output of the CT x-ray system shall be performed by a licensed medical physicist with a specialty in diagnostic radiological physics as follows.

       1. (A) Performance of the measurements shall be:

          1. (i) at intervals not to exceed 12 months;
          2. (ii) when major maintenance, except x-ray tube replacement, that could affect radiation output is performed; and
          3. (iii) when a major change in equipment operation (e.g., introduction of a new software package) is accomplished.
       2. (B) Measurements of the radiation output of a CT x-ray system shall be performed with a calibrated dosimetry system. The dosimetry system shall have been calibrated within the preceding 24 months and shall be traceable to a national standard. During the calendar year in which the dosimetry system is not calibrated, an intercomparison to a system calibrated within the previous 12 months shall be performed.
       3. (C) Records of dose measurements shall be maintained by the registrant in accordance with subsection (cc)(2) of this section.

    4. (4) A maintenance schedule shall be developed in accordance with the manufacturer's United States Department of Health and Human Services maintenance schedule. The schedule shall include but may not be limited to the following:

       1. (A) dose measurements required by paragraph (3)(A) of this subsection; and

       2. (B) acquisition of images obtained with phantoms using the same processing mode and CT conditions of operation as are used to perform dose measurements required by paragraph (3)(A) of this subsection. The registrant shall retain either of the following in accordance with subsection (cc)(2) of this section for inspection by the agency:

          1. (i) photographic copies of the images obtained from the image display device; or
          2. (ii) images stored in digital form.

23. (w) Requirements for bone densitometers. Bone densitometers shall be exempt from this chapter except for the following:

    1. (1) §289.112 of this title, §289.114 of this title, §289.201 of this title, §289.202 of this title, §289.204 of this title, and §289.226 of this title;
    2. (2) purpose and scope in accordance with subsection (a)(1) and (2) of this section;
    3. (3) prohibitions in accordance with subsection (b)(1) and (2) of this section;
    4. (4) exemptions in accordance with subsection (c) of this section;
    5. (5) definitions in accordance with subsection (d) of this section, as applicable;
    6. (6) operating and safety procedures in accordance with subsection (e)(2) of this section;
    7. (7) records in accordance with subsection (e)(5) of this section;
    8. (8) operator credentialing in accordance with subsection (e)(6) of this section;
    9. (9) healing arts screening and medical research in accordance with subsection (f) of this section;
    10. (10) gonadal shielding in accordance with subsection (i)(4) of this section;
    11. (11) record requirements for mobile services in accordance with subsection (n)(1)(A)-(D) and (G) of this section and subsection (n)(2)(A)-(G) of this section;
    12. (12) record requirements for authorized use locations in accordance with subsection (n)(3)(A)-(I) and (Q) of this section; and
    13. (13) warning labels in accordance with subsection (o).

24. (x) X-ray therapy equipment operating below 500 kV for all facilities.

    1. (1) Equipment requirements are as follows.

       1. (A) When the tube is operated at its leakage technique factors, the leakage radiation shall not exceed the values specified at the distance stated for the classification of that x-ray system shown in the following Table III.

25. (y) X-ray and electron beam therapy equipment operating at 500 kV and above for all facilities. Section 289.119 of this title (relating to Radiation Safety Requirements for Particle Accelerators) shall apply to medical facilities using therapy systems with energies 500 kV and above, except that area monitors required by 35.11(c) of TRCR Part 35 as adopted by reference in §289.119 of this title shall be functionally tested at intervals not to exceed one year.

    1. (1) Equipment requirements are as follows.

       1. (A) For operating conditions producing maximum leakage radiation, the absorbed dose in rads due to leakage radiation, including x-rays, electrons, and neutrons, at any point in a circular plane of 2 m radius centered on and perpendicular to the central axis of the beam at the isocenter or normal treatment distance and outside the maximum useful beam size shall not exceed 0.1% of the maximum absorbed dose in rads of the unattenuated useful beam measured at the point of intersection of the central axis of the beam and the plane surface. Measurements excluding those for neutrons shall be averaged over an area up to, but not exceeding, 100 cm[sup]2[/sup] at the positions specified. Measurements of the portion of the leakage radiation dose contributed by neutrons shall be averaged over an area up to, but not exceeding, 200 cm[sup]2[/sup]. For each system, the registrant shall determine or obtain from the manufacturer the leakage radiation existing at the positions specified for the specified operating conditions. Records on leakage radiation measurements shall be maintained in accordance with subsection (cc)(2) of this section for inspection by the agency.
       2. (B) Adjustable or interchangeable beam-limiting devices shall be provided and such devices shall transmit no more than 4.0% of the useful photon beam at the normal treatment distance for the portion of the useful beam that is to be attenuated by the beam-limiting device. The neutron component of the useful beam shall not be included in this requirement.

       3. (C) Filter requirements shall be as follows.

          1. (i) Each filter that is removable from the system shall be clearly marked with an identification number. Documentation available at the control panel shall contain a description of the filter. For wedge filters, the wedge angle shall appear on the wedge or wedge tray (if permanently mounted to the tray). If the wedge tray is damaged, the wedge transmission factor shall be redetermined.
          2. (ii) If the absorbed dose rate data required by subparagraph (P) of this paragraph relates exclusively to operation with a field-flattening filter or beam scattering foil in place, such filter shall be removable only by the use of tools.

          3. (iii) For new equipment that utilizes a system of wedge filters, interchangeable field-flattening filters, or interchangeable beam scattering foils, the following shall apply:

             1. (I) irradiation shall not be possible until a selection of a filter or a positive selection to use "no filter" has been made at the treatment control panel, either manually or automatically;
             2. (II) an interlock system shall be provided to prevent irradiation if the filter selected is not in the correct position;
             3. (III) a display shall be provided at the treatment control panel showing the beam quality in use; and
             4. (IV) an interlock shall be provided to prevent irradiation if any filter selection operation carried out in the treatment room does not agree with the filter selection operation carried out at the treatment control panel.

       4. (D) Beam quality. The registrant shall determine data sufficient to assure that the following beam quality requirements in tissue equivalent material are met.

          1. (i) The absorbed dose resulting from x-rays in a useful electron beam at a point on the central axis of the beam 10 cm greater than the practical range of the electrons shall not exceed the values stated in the following Table IV. Linear interpolation shall be used for values not stated.

26. (z) Radiation therapy simulators.

    1. (1) Radiation therapy simulators are exempt from this chapter except for the following:

       1. (A) §289.112 of this title, §289.114 of this title, §289.201 of this title, §289.202 of this title, §289.204 of this title, and §289.226 of this title;
       2. (B) purpose and scope in accordance with subsection (a)(1) and (2) of this section;
       3. (C) prohibitions in accordance with subsection (b) of this section;
       4. (D) exemptions in accordance with subsection (c) of this section;
       5. (E) definitions in accordance with subsection (d) of this section, as applicable;
       6. (F) technique charts in accordance with subsection (e)(1) of this section;
       7. (G) operating and safety procedures in accordance with subsection (e)(2) of this section;
       8. (H) protective devices in accordance with subsection (e)(4) of this section;
       9. (I) records in accordance with subsection (e)(5) of this section;
       10. (J) operator credentialing in accordance with subsection (e)(6) of this section;
       11. (K) viewing systems in accordance with subsection (i)(1) of this section;
       12. (L) x-ray control in accordance with subsection (i)(2) of this section;
       13. (M) record requirements for authorized use locations as applicable in accordance with subsection (n)(3) of this section; and
       14. (N) warning labels in accordance with subsection (o) of this section.

    2. (2) Additional requirements for radiation therapy simulators used in the general radiographic mode of operation.

       1. (A) Beam quality (HVL) shall be in accordance with subsection (o)(5)(A)(i) of this section.
       2. (B) Technique and exposure indicators shall be in accordance with subsection (o)(7)(A), (C), and (D) of this section.

       3. (C) Beam limitation shall be as follows.

          1. (i) The beam limiting device (collimator) shall restrict the useful beam to the area of clinical interest.
          2. (ii) A method shall be provided to visually define the center (cross-hair centering) of the x-ray field to within a 2 mm diameter.
          3. (iii) The beam limiting device (collimator) shall numerically indicate the field size.
          4. (iv) When an optical distance indicator (ODI) is present, it shall be accurate to within 2 mm.
          5. (v) When field delineator wires are present, the coincidence with the x-ray field shall be within 2 mm.
       4. (D) X-ray control shall be in accordance with subsection (s)(2)(A) of this section.
       5. (E) Timers shall be in accordance with subsection (s)(2)(B) of this section. In addition, a visual and/or audible signal shall indicate when an exposure has been terminated.
       6. (F) AEC shall be in accordance with subsection (s)(2)(C)(i) of this section.
       7. (G) Timer reproducibility shall be in accordance with subsection (s)(2)(D) of this section.
       8. (H) Exposure reproducibility shall be in accordance with subsection (s)(4) of this section.
       9. (I) Linearity shall be in accordance with subsection (s)(5) of this section.

    3. (3) Additional requirements for radiation therapy simulators utilizing fluoroscopic capabilities are as follows.

       1. (A) Activation of the fluoroscopic tube shall be in accordance with subsection (r)(2) of this section.
       2. (B) Indication of potential and current shall be in accordance with subsection (r)(4) of this section.
       3. (C) The SSD shall be in accordance with subsection (r)(5)(D) of this section.
       4. (D) Fluoroscopic timers shall be in accordance with subsection (r)(6) of this section.
       5. (E) Simulators must duplicate the geometric conditions of the radiation therapy equipment plan and therefore spot checks regarding geometric conditions shall be performed in accordance with subsection (y)(3)(D)(i) of this section.

27. (aa) Therapy misadministrations.

    1. (1) Misadministrations involving equipment operating at 500 kV and below shall be reported when:

       1. (A) it involves the wrong individual, wrong mode of treatment, or wrong treatment site;
       2. (B) the treatment consists of three or fewer fractions and the calculated total administered dose differs from the total prescribed dose by more than 10% of the total prescribed dose;
       3. (C) the calculated weekly administered dose exceeds the weekly prescribed dose by 30% or more; or
       4. (D) the calculated total administered dose differs from the total prescribed dose by more than 20% of the total prescribed dose.

    2. (2) Misadministrations involving equipment operating above 500 kV shall be reported when:

       1. (A) it involves the wrong individual, wrong mode of treatment, or wrong treatment site;
       2. (B) the treatment consists of three or fewer fractions and the calculated total administered dose differs from the total prescribed dose by more than 10% of the total prescribed dose;
       3. (C) the calculated weekly administered dose exceeds the weekly prescribed dose by 30% or more; or
       4. (D) the calculated total administered dose differs from the total prescribed dose by more than 20% of the total prescribed dose.

28. (bb) Records, notices, and reports of misadministrations.

    1. (1) For a misadministration, a registrant shall:

       1. (A) notify the agency by telephone no later than 24 hours after discovery of the misadministration;
       2. (B) notify the referring physician and also notify the patient of the misadministration no later than 24 hours after its discovery, unless the referring physician personally informs the registrant either that he or she will inform the patient or that, based on medical judgement, telling the patient would be harmful. The registrant is not required to notify the patient without first consulting the referring physician. If the referring physician or patient cannot be reached within 24 hours, the registrant shall notify the patient as soon as possible thereafter. The registrant may not delay any appropriate medical care for the patient, including any necessary remedial care as a result of the misadministration, because of any delay in notification;

       3. (C) submit a written report to the agency within 15 days after the discovery of the misadministration. The report must not include the patient's name or other information that could lead to identification of the patient. The written report must include the following:

          1. (i) registrant's name;
          2. (ii) prescribing physician's name;
          3. (iii) a brief description of the event;
          4. (iv) why the event occurred;
          5. (v) the effect on the patient;
          6. (vi) what improvements are needed to prevent recurrence;
          7. (vii) actions taken to prevent recurrence;
          8. (viii) whether the registrant notified the patient, or the patient's responsible relative or guardian (this person will be subsequently referred to as "the patient"; and if not, why not; and
          9. (ix) if the patient was notified, what information was provided to the patient; and

       4. (D) furnish the following to the patient within 15 days after discovery of the misadministration if the patient was notified:

          1. (i) a copy of the report that was submitted to the agency; or
          2. (ii) a brief description of both the event and the consequences, as they may affect the patient, provided a statement is included that the report submitted to the agency can be obtained from the registrant.

    2. (2) Each registrant shall retain a record of each misadministration in accordance with subsection (cc)(2) of this section. The record shall contain the following:

       1. (A) the names of all individuals involved (including the prescribing physician, allied health personnel, the patient, and the patient's referring physician);
       2. (B) the patient's social security number or identification number if one has been assigned;
       3. (C) a brief description of the misadministration;
       4. (D) why it occurred;
       5. (E) the effect on the patient;
       6. (F) what improvements are needed to prevent recurrence; and
       7. (G) the actions taken to prevent recurrence.
    3. (3) Aside from the notification requirement, nothing in subsection (aa) of this section and paragraphs (1) and (2) of this subsection shall affect any rights or duties of registrants, and physicians in relation to each other, patients, or the patient's responsible relatives or guardians.

29. (cc) Appendices.

    1. (1) Information to be submitted by persons proposing to conduct healing arts screening. Persons requesting that the agency approve a healing arts screening program shall submit the following information and evaluation.

       1. (A) Administrative controls shall include the following:

          1. (i) the name and address of the applicant and, where applicable, the names and addresses of agents within Texas;
          2. (ii) the diseases or conditions for which the x-ray examinations are to be used in diagnoses;
          3. (iii) a detailed description of the x-ray examinations proposed in the screening program;
          4. (iv) a description of the population to be examined in the screening program (i.e., age, sex, physical condition, and other appropriate information); and
          5. (v) an evaluation of any known alternate methods not involving ionizing radiation that could achieve the goals of the screening program and why these methods are not used instead of the x-ray examination.

       2. (B) Operating procedures for all x-ray systems (except bone densitometers) shall include the following:

          1. (i) an evaluation of the x-ray systems to be used in the screening program. The evaluation shall be performed by a licensed medical physicist with a specialty in diagnostic radiological physics. The evaluation shall show that such systems do satisfy all requirements of this section;
          2. (ii) a description of the diagnostic film quality control program; and
          3. (iii) a copy of the technique chart for the x-ray examination procedures to be used.
       3. (C) Operating procedures for bone densitometers shall include the manufacturer's evaluation of the system to be used in the screening program. The evaluation shall show that such systems do satisfy all requirements of this section.

       4. (D) Training data shall include the following:

          1. (i) the qualifications of each individual who will be operating the x-ray systems;
          2. (ii) the qualifications of the individual who will be supervising the operators of the x-ray systems. The extent of supervision and the method of work performance evaluation shall be specified; and
          3. (iii) the name and address of the practitioner who will interpret the radiographs.

       5. (E) Records shall include the following:

          1. (i) a description of the procedures to be used in advising the individuals screened, and their private practitioners of the healing arts, of the results of the screening procedure and any further medical needs indicated; and
          2. (ii) a description of the procedures for the retention or disposition of the radiographs and other records pertaining to the x-ray examinations.
    2. (2) Retention requirements for record keeping.

Source Note:The provisions of this §289.227 adopted to be effective June 1, 1998, 23 TexReg 3467.