6 Colo. Code Regs. § 1007-1-6.7

Current through Register Vol. 47, No. 11, June 10, 2024

Section 6 CCR 1007-1-6.7 - Requirements for use of dental imaging systems

6.7.1 Administrative Controls.

6.7.1.1 Intraoral dental x-ray machines shall not be operated at less than a measured 51 kVp, after January 1, 2022.

6.7.1.2 All dental facilities using any type of x-ray equipment for dental x-ray imaging, shall:

(1) Follow the applicable requirements of 6.3 and 6.4;

(2) Follow the applicable requirements of this Section 6.7

6.7.1.3 In addition to the requirements of 6.7.1.2, dental facilities using cone beam computed tomography (CBCT) x-ray equipment for dental x-ray imaging, shall also follow the requirements of Section 6.9 that are applicable to CBCT.

6.7.1.4 Quality assurance. In addition to the general quality assurance provisions in Section 6.3, the following requirements apply to a dental facility:

(1) If using a filmless system, maintain and operate PSP and DDR systems according to manufacturer specifications, or nationally accepted standards.

(2) If using film:

(a) Maintain a light tight darkroom or processor system;

(b) Use proper safelighting and safeguards; and

(c) Evaluate darkroom or processor system integrity and daylight loading systems for film fog every six months and after a change that may impact film fog.

6.7.1.5 Each individual who operates a dental x-ray imaging system shall meet the applicable adequate radiation safety training and experience requirements of Part 2, sections 2.6.1, and specifically 2.6.1.11.

(1) Records of training shall be maintained for inspection by the Department in accordance with Part 2, Section 2.6.6.4.

6.7.2 Each dental x-ray imaging system shall meet the following equipment design and configuration requirements.

6.7.2.1 Warning Label.

(1) Warning labels shall be maintained in accordance with 6.4.2.1.

6.7.2.2 Cephalometric and volumetric dental imaging systems shall meet the equipment design and configuration requirements of 6.3.2 and 6.6.2, except that:

(1) The shielding design described in 6.3.2 is required for the imaging room(s) of any facility having a cephalometric or volumetric dental imaging system, or a system that can be operated in a cephalometric mode regardless of the occupancy of adjoining rooms.

(2) A dental facility may apply to the Department in writing and may be granted an exemption from the requirements of 6.7.2.2 for a particular room and x-ray equipment configuration.

6.7.2.3 Intraoral and panoramic dental x-ray systems shall meet the following requirements:

(1) The useful x-ray beam shall be limited to the area of clinical interest.

(2) Source-Skin Distance (SSD) for Intraoral Dental X-ray Systems.

(a) X-ray imaging system designed for use with an intraoral image receptor shall be provided with means to limit the SSD, to not less than 18 cm if operable above 50 kVp.

(3) Field Limitation for Intraoral Dental X-ray Systems.

(a) Each x-ray imaging system designed for use with an intraoral image receptor shall be provided with means to limit the beam such that:

(i) If the minimum SSD is 18 cm or more, the x-ray field, at the minimum SSD, shall be containable in a circle having a diameter of no more than 7 cm; and

(ii) If the minimum SSD is less than 18 cm, the x-ray field, at the minimum SSD, shall be containable in a circle having a diameter of no more than 6 cm.

(4) As provided in 6.3.2.4, neither the shielding design described in 6.3.2 nor the dimensional drawing, calculation or survey described in 6.3.2.3 are required for intraoral or panoramic dental equipment.

6.7.2.4 Extraoral, panoramic and cephalometric units.

(1) X-ray systems designed for use with extraoral image receptors and when used with an extraoral image receptor, shall be provided with means 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 percent of the SID, when the axis of the x-ray beam is perpendicular to the plane of the image receptor. In addition, means shall be provided to align the center of the x-ray field with the center of the image receptor to within 2 percent of the SID, or means shall be provided to both size and alignment 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.

The requirements of 6.7.2.4(1) may be met with:

(a) 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. Each such device shall have clear and permanent markings to indicate the image receptor size and SID for which it is designed; or

(b) 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.

6.7.2.5 Modification of diagnostic x-ray components and systems shall be done only in accordance with 6.3.1.2(3).

6.7.3 Each dental x-ray imaging system shall meet the following radiation exposure operational control requirements.

6.7.3.1 Cephalometric and volumetric beam dental x-ray systems shall meet the radiation exposure control requirements of 6.6.3:

6.7.3.2 Intraoral and panoramic dental x-ray systems shall meet the following radiation exposure control requirements:

(1) Timers.

(a) Means shall be provided to terminate the exposure at a preset time interval, preset product of current and time, a preset number of pulses, or a preset radiation exposure to the image receptor.

(b) 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.

(c) Termination of exposure shall cause automatic resetting of the timer to its initial setting or to "zero".

(d) Timer Reproducibility.

(i) With a timer setting of 0.5 seconds or less, the average exposure period (T_avg) shall be greater than or equal to five (5) times the maximum exposure period (T_max) minus the minimum exposure period (T_min) when four (4) timer tests are performed: T_avg>= 5(T_max - T_min).

(2) X-ray Control for Intraoral or Panoramic Dental X-ray Systems.

(a) Means shall be provided to initiate the radiation exposure by a deliberate action on the part of the operator, such as the depression of a switch. Radiation exposure shall not be initiated without such an action.

(b) A control shall be incorporated into each x-ray imaging system such that an exposure can be terminated by the operator at any time, except for exposures of one-half (0.5) second or less.

(c) Exposure control location and operator protection.

Except for units designed to be hand-held during operation, the exposure control shall allow the operator to be:

(i) Behind a protective barrier at least 2 meters (more than 6 feet) tall; or

(ii) At least 2 meters (more than 6 feet) from the patient, x-ray tube, and the useful beam, while making exposures.

(d) The requirements of Appendix 6E shall be followed for x-ray equipment intended to be hand held during operation.

(3) Accuracy.

(a) Deviation of exposure settings from indicated values shall not exceed the limits specified for that system by its manufacturer.

(b) If manufacturer specifications are not available, accuracy of all exposure factors shall be within ten (10) percent of the selected factor(s).

(4) Beam Quality.

(a) All dental x-ray systems shall have a minimum half-value layer not less than 1.5 millimeters aluminum equivalent.

(b) Systems operating above 70 kVp are subject to the filtration requirements of 6.4.2.5(1).

(c) The Half Value Layer (HVL) of the useful beam for a given x-ray tube potential shall not be less than the values shown in Appendix 6I. If it is necessary to determine such half-value layer at an x-ray tube potential which is not listed in Appendix 6I, linear interpolation or extrapolation may be made.

(i) Positive means shall be provided to ensure that at least the minimum filtration needed to achieve beam quality requirements is in the useful beam during each exposure.

(ii) In the case of a system, which is to be operated with more than one thickness of filtration, this requirement can be met by a filter interlocked with the kilovoltage selector which will prevent x-ray emissions if the minimum required filtration is not in place.

(5) Patient and image receptor holding devices shall be used when the techniques permit.

(6) Except for units designed to be hand held during operation, the tube housing and position indicating device (PID) shall not be hand-held during an exposure.

(7) The x-ray system shall be operated in such a manner that the area of the useful beam at the patient's skin is minimized while ensuring adequate coverage of relevant anatomy.

(8) Dental fluoroscopy without image intensification or direct digital receptors shall not be used.

6.7.3.3 The x-ray control shall provide:

(1) Visual indication observable at the operator's protected position whenever x-rays are produced; and

(2) A signal audible to the operator shall indicate that the exposure has terminated.

6.7.3.4 Excluding cases in which shielding would interfere with the diagnostic procedure, thyroid shielding shall be required for pediatric patients when performing intra-oral imaging.

6.7.3.5 Absent structural protection against scatter radiation, during radiation machine operation at least a 2-meter distance (more than 6 feet) shall be maintained from any bystander location and between patient operating chairs.

6.7.3.6 Multiple tubes. Where two or more radiographic tubes are controlled by one exposure switch, the tube which has been selected shall be clearly indicated prior to initiation of the exposure. Only the selected tube can be energized.

(1) This indication shall be both on the x-ray control panel and at or near the tube housing assembly which has been selected.

6.7.3.7 Mechanical support of tube head. Excluding hand-held systems, tube housing assembly supports shall be adjusted such that the tube housing assembly will remain stable during an exposure unless tube housing movement is a designed function of the x-ray system.

6.7.3.8 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.

6.7.3.9 All position locking, holding, and centering devices on the x-ray system and/or components shall function as intended.

6.7.3.10 For x-ray equipment capable of displaying technique factors, the technique factors to be used during an exposure shall be indicated before the exposure begins.

(1) If automatic exposure controls are used, the technique factors which are set prior to the exposure shall be indicated.

(2) The requirement of 6.7.3.10(1) may be met by permanent markings on equipment having fixed technique factors.

6.7.3.11 For any specific combination of selected technique factors, the coefficient of variation of the air kerma shall be no greater than 0.05.

6.7.3.12 Deviation of technique factors from indicated values shall not exceed the limits provided by the manufacturer.

(1) At a minimum, the kVp on variable kVp units shall be accurate to within 10 percent and within 20 percent on fixed kVp units.

6.7.4 For each dental x-ray imaging system, manufacturer maintenance specifications shall be followed.

6.7.5 For each dental x-ray imaging system, written quality control and quality assurance procedures shall include:

6.7.5.1 For manual processing of intraoral films, performance of the following:

(1) Follow applicable manufacturer's time and temperature specifications, which shall be available for review;

(2) Measure and log temperature each day of use; and

(3) Document in a written log the change of developer chemicals at least every month.

6.7.5.2 For volumetric dental imaging systems, conduct periodic calibrations and annual quality control tests according to the manufacturer's specifications, including any additional or more frequent testing necessary at the recommendation of the registered medical physicist or consistent with the standards of an appropriate nationally recognized organization, for example, the American Association of Physicists in Medicine.

6.7.5.3 Annual review of all quality control tests.

6 CCR 1007-1-6.7

Colorado Register, Vol 37, No. 14. July 25, 2014, effective 8/14/2014

38 CR 02, January 25, 2015, effective 2/14/2015

38 CR 05, March 10, 2015, effective 3/30/2015

38 CR 12, June 25, 2015, effective 7/15/2015

38 CR 14, July 25, 2015, effective 8/14/2015

39 CR 02, January 25, 2016, effective 2/14/2016

39 CR 16, August 25, 2016, effective 9/14/2016

39 CR 22, November 25, 2016, effective 12/15/2016

40 CR 11, June 10, 2017, effective 6/30/2017

40 CR 20, October 25, 2017, effective 11/14/2017

42 CR 24, December 25, 2019, effective 1/14/2020

43 CR 14, July 25, 2020, effective 8/14/2020

43 CR 18, September 25, 2020, effective 10/15/2020

44 CR 11, June 10, 2021, effective 7/15/2021

44 CR 14, July 25, 2021, effective 8/14/2021

45 CR 22, November 25, 2022, effective 12/15/2022

47 CR 06, March 25, 2024, effective 4/14/2024