4.14.1ApplicabilityIn addition to the applicable requirements of §§ 4.3 and 4.4 of this Part, the requirements of § 4.14 of this Part apply to dental facilities using intraoral, panoramic, and cephalometric X-ray equipment. Dental facilities using cone beam computed tomography (CBCT) technology shall follow applicable provisions of §4.7.8 of this Part.
4.14.2Warning LabelA. On systems manufactured on or before June 10, 2006, the control panel containing the main power switch shall bear the following warning statement or the warning statement in §4.14.2(B) of this Part, legible and accessible to view: "WARNING: This X-ray unit may be dangerous to patient and operator unless safe exposure factors and operating instructions are observed."B. On systems manufactured after June 10, 2006, the control panel containing the main power switch shall bear the warning statement, legible and accessible to view: "WARNING: This X-ray unit may be dangerous to patient and operator unless safe exposure factors, operating instructions and maintenance schedules are observed."4.14.3Radiation Exposure ControlMeans 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.
4.14.4Exposure Control Location and Operator ProtectionA. Except for units designed to be hand-held, the exposure control shall allow the operator to be: 1. Behind a protective barrier at least two meters (2 m) (six and one half feet (6.5')) tall or 2. At least two meters (2 m) (six and one half feet (6.5')) from the tube housing assembly, outside the path of the useful X-ray beam, while making exposures.4.14.5Administrative ControlsA. Patient and image receptor holding devices shall be used when the techniques permit.B. Except for units designed to be hand-held, the tube housing and position indicating device (PID) shall not be hand-held during an exposure.C. Dental fluoroscopy without image intensification shall not be used. 4.14.6Beam-on IndicatorsThe X-ray control shall provide visual indication whenever X-rays are produced. In addition, a signal audible to the operator shall indicate that the exposure has terminated.
4.14.7Multiple TubesWhere two (2) or more radiographic tubes are controlled by one (1) 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. This indication shall be both on the X-ray control panel and at or near the tube housing assembly which has been selected.
4.14.8Mechanical Support of Tube HeadThe 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.
4.14.9Battery Charge IndicatorOn battery-powered generators, visual means shall be provided on the control panel to indicate whether the battery is in a state of charge adequate for proper operation.
4.14.10LocksAll position locking, holding, and centering devices on X-ray system components and systems shall function as intended.
4.14.11Technique IndicatorsA. 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. If automatic exposure controls are used, the technique factors which are set prior to the exposure shall be indicated.B. The requirement of §4.14.11(A) of this Part may be met by permanent markings on equipment having fixed technique factors.4.14.12Exposure ReproducibilityFor any specific combination of selected technique factors, the estimated coefficient of variation of the air kerma shall be no greater than five one hundredths (0.05).
4.14.13TimersMeans 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.
4.14.14 Kilovolt PeakDeviation of technique factors from indicated values shall not exceed the limits provided by the manufacturer. (variation of 21 C.F.R. § 1020.31(a)(4)). At a minimum, the kVp on variable kVp units shall be accurate to within ten percent (10%) and within twenty percent (20%) on fixed kVp units.
4.14.15X-ray Beam AlignmentA. The useful X-ray beam shall be limited to the area of clinical interest.B Intraoral Dental Units1. X-ray systems designed for use with an intraoral image receptor shall be provided with means to limit the source-to-skin distance (SSD) to not less than eighteen centimeters (18 cm).2. The X-ray field at the minimum SSD shall be containable in a circle having a diameter of no more than seven centimeters (7 cm).C. Extraoral, Panoramic and Cephalometric Units1. 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 two percent (2%) 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 two percent (2%) of the SID, or means shall be provided to both size and alignment of 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. These requirements 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.4.14.16Beam QualityA. 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 §4.14.16(B) of this Part [Table 1]. If it is necessary to determine such half-value layer at an X-ray tube potential which is not listed in §4.14.16(B) of this Part, linear interpolation or extrapolation may be made. 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. In the case of a system, which is to be operated with more than one (1) 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.B. Table 1 - X-Ray Tube Voltage (kilovolt peak) | Minimum HVL (mm in Aluminum) |
Design Operating Range | Measured Operating Potential | Dental X-ray systems designed for use with intraoral image receptors and manufactured after December 1, 1980 | Dental X-ray systems designed for use with intraoral image receptors and manufactured before or on December 1, 1980 | All X-ray systems, except dental X-ray systems designed for use with intraoral image receptors, subject to §4.14.16 of this Part and manufactured on or after June 10, 2006 |
Below 51 | 30 | 1.5 | 0.3 | 0.3 |
40 | 1.5 | 0.4 | 0.4 |
50 | 1.5 | 0.5 | 0.5 |
51 to 70 | 51 | 1.5 | 1.2 | 1.3 |
60 | 1.5 | 1.3 | 1.5 |
70 | 1.5 | 1.5 | 1.8 |
Above 70 | 71 | 2.1 | 2.1 | 2.5 |
80 | 2.3 | 2.3 | 2.9 |
90 | 2.5 | 2.5 | 3.2 |
100 | 2.7 | 2.7 | 3.6 |
110 | 3.0 | 3.0 | 3.9 |
120 | 3.2 | 3.2 | 4.3 |
130 | 3.5 | 3.5 | 4.7 |
140 | 3.8 | 3.8 | 5.0 |
150 | 4.1 | 4.1 | 5.4 |
4.14.17kVp LimitationsIntraoral dental X-ray machines with a measured kVp of less than fifty-one (51) kVp shall not be used to make diagnostic dental radiographs of humans.
4.4.18Modification of Certified Diagnostic X-ray Components and EquipmentA. Diagnostic X-ray components and equipment certified in accordance with 21 C.F.R. Part 1020 shall not be modified such that the component or equipment fails to comply with any applicable provision of 21 C.F.R. Part 1020.B. The owner of a diagnostic X-ray equipment who uses the equipment in a professional or commercial capacity may modify the equipment provided the modification does not result in the failure of the equipment or component to comply with the applicable requirements of 21 C.F.R. Part 1020 . The owner who causes such modification need not submit the reports required by 21 C.F.R. Part 1020, provided the owner records the date and the details of the modification in the equipment records and maintains this information, and provided the modification of the X-ray system does not result in a failure to comply with 21 C.F.R. Part 1020.4.14.19Leakage Radiation from the Diagnostic Source AssemblyThe leakage radiation from the diagnostic source assembly measured at a distance of one meter (1 m) in any direction from the source shall not exceed eighty-eight one hundredths milligray (0.88 mGy) air kerma (vice one hundred milliroentgen (100 mR) exposure) in one (1) hour when the X-ray tube is operated at its leakage technique factors. If the maximum rated peak tube potential of the tube housing assembly is greater than the maximum rated peak tube potential for the diagnostic source assembly, positive means shall be provided to limit the maximum X-ray tube potential to that of the diagnostic source assembly. Compliance shall be determined by measurements averaged over an area of one hundred square centimeters (100 cm2) with no linear dimension greater than twenty centimeters (20 cm).
4.14.20Radiation from Components Other Than the Diagnostic Source AssemblyThe radiation emitted by a component other than the diagnostic source assembly shall not exceed an air kerma of eighteen (18) microgray (two (2) milliroentgens exposure) in one (1) hour at five centimeters (5 cm) from any accessible surface of the component when it is operated in an assembled X-ray system under any conditions for which it was designed. Compliance shall be determined by measurements averaged over an area of one hundred square centimeters (100 cm2) with no linear dimension greater than twenty centimeters (20 cm).
4.14.21Maintaining ComplianceDiagnostic X-ray systems and their associated components used on humans and certified pursuant to the Federal X-Ray Equipment Performance Standard (21 C.F.R. Part 1020) shall be maintained in compliance with applicable requirements of that standard.
216 R.I. Code R. § 216-RICR-40-20-4.14
Adopted effective 5/25/2022
Amended effective 11/28/2023