§ 175.49 Specific Requirements for Dental Facilities.
RCNY § 175.49
(a)The following specific quality assurance requirements apply to a dental facility: (1) If using a filmless system, maintain and operate PSP and DDR systems according to manufacturer specifications.
(2)The registrant must provide initial training and annual evaluations of x-ray operators to include but not limited to: positioning of the x-ray tube, image processing, operator location during x-ray exposure, source to skin distance, radiation protection, appropriate radiographic protocol and applicable regulatory requirements. Records of training and annual evaluations must be maintained for inspection by the Department.
(b)Warning label.
(1)On systems manufactured on or before June 10, 2006, the control panel containing the main power switch must bear the following warning statement, or the warning statement in paragraph (2) of this subdivision, 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." (2) On systems manufactured after June 10, 2006, the control panel containing the main power switch must 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." (c) Radiation exposure control. Means must 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 must not be initiated without such an action.
(d)Exposure control location and operator protection. Except for units designed to be hand-held, the exposure control must allow the operator to be: (1) behind a protective barrier at least 2 meters (6.5 feet) tall, or (2) at least 2 meters (6.5 feet) from the tube housing assembly, outside the path of the useful x-ray beam, while making exposures.
(e)Administrative controls.
(f)Hand-held intraoral equipment. In addition to other requirements in this Article, the following applies specifically to hand-held devices: (1) The hand-held x-ray system must be equipped with a backscatter shield of not less than 0.25 mm lead equivalent and 15.2 cm (6 inches) in diameter that is positioned as close as practicable to the distal end of the position indication device.
(3)The facility must adopt and follow protocols provided by the manufacturer, and approved by the Department, regarding the safe operation of the device.
(4)When operating a hand-held intraoral dental radiographic unit, operators must wear a 0.25 mm lead equivalent apron.
(5)If the operator has difficulty in holding the device stationary during the exposure, the operator shall use a stand to immobilize the device.
(6)The registrant must secure the hand-held device from unauthorized removal or use.
(g)Beam-on indicators. The x-ray control must provide visual indication whenever x- rays are produced. In addition, for certified x-ray units, a signal audible to the operator must indicate that the exposure has terminated.
(h)Multiple tubes. Where two or more radiographic tubes are controlled by one exposure switch, the tube which has been selected must be clearly indicated prior to initiation of the exposure. Only the selected tube can be energized. This indication must be both on the x-ray control panel and at or near the tube housing assembly which has been selected.
(i)Mechanical support of tube head. The tube housing assembly supports must 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.
(j)Battery charge indicator. On battery-powered generators, visual means must be provided on the control panel to indicate whether the battery is in a state of charge adequate for proper operation.
(k)Technique indicators.
(l)Exposure reproducibility. For any specific combination of selected technique factors, the estimated coefficient of variation of the air kerma must be no greater than 0.05.
(m)Timers. Means must 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.
(n)Kilovolt peak. At a minimum, the kVp must be accurate to within 10 percent on variable kVp units and within 20 percent on fixed kVp units.
(o)X-ray beam alignment.
(ii)The x-ray field at the minimum SSD must be containable in a circle having a diameter of no more than 7 cm.
(p)Beam quality. The Half Value Layer (HVL) of the useful beam for a given x-ray tube potential must not be less than the values shown in Table 1 of 24 RCNY Health Code § 175.47(u). If it is necessary to determine such half-value layer at an x-ray tube potential which is not listed in Table 1, linear interpolation or extrapolation may be made.
(q)Conditions of use.
(r)Facilities possessing a Cone Beam Computed Tomography (CBCT) unit.
(iii)Semi-annual QA tests to determine image noise, image uniformity, reconstructed image measurement accuracy, high contrast spatial resolution of the CBCT unit.
(iv)Dental facilities possessing a CBCT unit must use a medical physicist who is a QMP in performing its QA activities.
(v)The logbook for CBCT exams must contain all relevant diagnostic examination information, including but not limited to, x-ray technique, scan time, anatomical exam site and reason for examination. (Added City Record 4/24/2019, eff. 5/24/2019)
