6 CCR 1007-1
PART 6 X-RAYS IN THE HEALING ARTS RH 6.1 Purpose and Scope.
This Part establishes requirements, for which a registrant is responsible, for use of x-ray equipment by or under the supervision of an individual authorized by and licensed in accordance with State statutes to engage in the healing arts or veterinary medicine. The provisions of this Part are in addition to, and not in substitution for, other applicable provisions of these Regulations. RH 6.2 Definitions.
“Accessible surface” means the external surface of the enclosure or housing provided by the manufacturer.
“Added filtration” means any filtration which is in addition to the inherent filtration. “Aluminum equivalent” means the thickness of type 1100 aluminum alloy 1 affording the same attenuation, under specified conditions, as the material in question. “Attenuation block” means a block or stack, having dimensions 20 centimeters by 20 centimeters by 3.8 centimeters, of type 1100 aluminum alloy 1 , or other materials having equivalent attenuation. 1 The nominal chemical composition of type 1100 aluminum alloy is 99.00 percent minimum aluminum, 0.12 percent copper. “Automatic exposure control” means a device which automatically controls one or more technique factors in order to obtain at a preselected location a required quantity of radiation (See also “Phototimer” ). “Barrier” (See “Protective barrier” ).
“Beam axis” means a line from the source through the centers of the x-ray field. “Beam-limiting device” means a device which provides a means to restrict the dimensions of the x-ray field.
“C-arm x-ray system” means an x-ray system in which the image receptor and x-ray tube housing assembly are connected by a common mechanical support system in order to maintain a desired spatial relationship. This system is designed to allow a change in the projection of the beam through the patient without a change in the position of the patient.
“Cephalometric device” means a device intended for the radiographic visualization and measurement of the dimensions of the human head.
“Certified components” means components of x-ray systems which are subject to regulations promulgated under Public Law 90-602, the Radiation Control for Health and Safety Act of 1968. “Certified system” means any x-ray system which has one or more certified component(s). “Changeable filters” means any filter, exclusive of inherent filtration, which can be removed from the useful beam through any electronic, mechanical, or physical process under operator control. “Coefficient of variation” or “C” means the ratio of the standard deviation to the mean value of a population of observations. It is estimated using the following equation: where s = Estimated standard deviation of the population.
n = Number of observations in sample.
“Computed tomography” means the production of a tomogram by the acquisition and computer processing of x-ray transmission data.
“Control panel” means that part of the x-ray control upon which are mounted the switches, knobs, pushbuttons, and other hardware necessary for the operator's use for manually setting the technique factors.
“Cooling curve” means the graphical relationship between heat units stored and cooling time. “CT” (See “Computed tomography” ).
“Dead-man switch” means a switch so constructed that a circuit closing contact can be maintained only by continuous pressure on the switch by the operator.
“Detector” (See “Radiation detector” ).
“Diagnostic source assembly” means the tube housing assembly with a beam-limiting device attached. “Diagnostic x-ray system” means an x-ray system designed and used for irradiation of any part of the human or animal body for the purpose of diagnosis or visualization. “Diagnostic x-ray imaging system” means an assemblage of components for the generation, emission, and reception of x-rays and the transformation, storage and visual display of the resultant x-ray image. “Direct scattered radiation” means that scattered radiation which has been deviated in direction only by materials irradiated by the useful beam (See “Scattered radiation” ). “Entrance exposure rate” means the exposure per unit time at the point where the center of the useful beam enters the patient.
“Equipment” (See “x-ray equipment” ).
“Field emission equipment” means equipment which uses an x-ray tube in which electron emission from the cathode is due solely to the action of an electric field. “Filter” means material placed in the useful beam to preferentially absorb selected radiations. “Fluoroscopic imaging assembly” means a subsystem in which x-ray photons produce a visible image. It includes the image receptor(s) such as the image intensifier and spot-film device, electrical interlocks if any, and structural material providing linkage between the image receptor and diagnostic source assembly.
“Focal spot (actual)” means the area projected on the anode of the x-ray tube bombarded by the electrons accelerated from the cathode and from which the useful beam originates. “General purpose radiographic x-ray system” means any radiographic x-ray system which, by design, is not limited to radiographic examination of specific anatomical regions. “Gonad shield” means a protective barrier for the testes or ovaries. “Half-value layer (HVL)” means the thickness of specified material which attenuates the beam of radiation to an extent such that the exposure rate is reduced by one-half of its original value. In this definition, the contribution of all scattered radiation, other than any which might be present initially in the beam, is deemed to be excluded.
“Healing arts screening” means the testing of human beings using x-ray machines for the detection or evaluation of health indications when such tests are not specifically and individually ordered by a licensed practitioner of the healing arts legally authorized to prescribe such x-ray test for the purpose of diagnosis or treatment.
“Image intensifier” means a device, installed in its housing, which instantaneously converts an x-ray pattern into a corresponding visible light image and electronically amplifies the brightness of that visible image.
“Image receptor” means any device, such as a fluorescent screen or radiographic film, which transforms incident x-ray photons either into a visible image or into another form which can be made into a visible image by further transformations.
“Image receptor support” means, for mammographic systems, that part of the system designed to support the image receptor perpendicular to the beam axis during a mammographic examination. “Inherent filtration” means the filtration of the useful beam provided by the permanently installed components of the tube housing assembly.
“Irradiation” means the exposure of matter to ionizing radiation. “Kilovolts peak” (See “Peak tube potential” ).
“kV” means kilovolts.
“kVp” (See “Peak tube potential” ).
“kWs” means kilowatt second.
“Lead equivalent” means the thickness of lead affording the same attenuation, under specified conditions, as the material in question.
“Leakage radiation” means radiation emanating from the diagnostic source assembly except for the useful beam.
“Leakage technique factors” means the technique factors associated with the diagnostic source assembly which are used in measuring leakage radiation. They are defined as follows:
(1) For diagnostic source assemblies intended for capacitor energy storage equipment, the maximum- rated peak tube potential and the maximum-rated number of exposures in an hour for operation at the maximum-rated peak tube potential with the quantity of charge per exposure being 10 millicoulombs, i.e., 10 milliampere seconds, or the minimum obtainable from the unit, whichever is larger;
(2) For diagnostic source assemblies intended for field emission equipment rated for pulsed operation, the maximum-rated peak tube potential and the maximum-rated number of x-ray pulses in an hour for operation at the maximum-rated peak tube potential.
(3) For all other diagnostic source assemblies, the maximum-rated peak tube potential and the maximum-rated continuous tube current for that potential. “Light field” means that area of the intersection of the light beam from the beam-limiting device, and one of the set of planes parallel to, and including, the plane of the image receptor, whose perimeter is the locus of points, at which the illumination is one-fourth of the maximum in the intersection. “Line-voltage regulation” means the difference between the no-load and the load line potentials expressed as a percent of the load line potential. It is calculated using the following equation: Percent line-voltage regulation = 100 (V -V )/V n l l where:
“mAs” means milliampere second.
“Maximum line current” means the root-mean-square current in the supply line of an x-ray machine operating at its maximum rating.
“Mini c-arm x-ray system(s)” means a system that meets the following criteria: source-image receptor distance less than or equal to 50 cm; field of view less than or equal to six (6) inches; kVp less than or equal to 75 kVp; mA less than or equal to 0.25 mA; and entrance exposure rate less than or equal to 10 roentgen (1.29 mC/kg) per minute at the exit port.
“Mobile x-ray equipment” (See “x-ray equipment” ).
“Optical Density (OD)” = Log (1/Transmittance), where the transmittance of the film is the fraction of incident light transmitted by the film.
“Patient” means an individual or animal subjected to healing arts examination, diagnosis, or treatment. “Peak tube potential” means the maximum value of the potential difference across the x-ray tube during an exposure.
“Phantom” means an object designed such that the interaction of ionizing radiation with the object is suitable for the evaluation of the particular characteristics of the x-ray system or anatomic region under consideration.
“Phototimer” means a method for controlling radiation exposure to image receptors by the amount of radiation which reaches a radiation monitoring device(s). The radiation monitoring device(s) is part of an electronic circuit which controls the duration of time the tube is activated (See “Automatic exposure control” ).
“Position indicating device (PID)” means 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.
“Positive beam limitation (PBL)” means the automatic or semi-automatic adjustment of an x-ray beam to the size of the selected image receptor, whereby exposures cannot be made without such adjustment. “Protective apron” means an apron made of radiation absorbing materials used to reduce radiation exposure to the wearer.
“Protective barrier” means a barrier of radiation absorbing material(s) used to reduce radiation exposure. The types of protective barriers are as follows:
(1) “Primary protective barrier” means the material, excluding filters, placed in the direct useful beam, for protection purposes, to reduce the radiation exposure;
(2) “Secondary protective barrier” means the material which attenuates stray radiation. “Protective glove” means a glove made of radiation absorbing materials used to reduce radiation exposure to the wearer.
“Radiation detector” means a device which in the presence of radiation provides a signal or other indication suitable for use in measuring one or more quantities of incident radiation. “Radiation therapy simulation system” means a radiographic or fluoroscopic x-ray system intended for localizing the volume to be exposed during radiation therapy and confirming the position and size of the therapeutic irradiation field.
“Radiograph” means an image receptor on which the image is created directly or indirectly by an x-ray pattern and results in a permanent record.
“Radiographic imaging system” means any system whereby a permanent or semipermanent image is recorded on an image receptor by the action of ionizing radiation. “Rating” means the operating limits as specified by the component manufacturer. “Recording” means producing a permanent form of an image resulting from x-ray photons. “Response time” means the time required for an instrument system to reach 90 percent of its final reading when the radiation-sensitive volume of the instrument system is exposed to a step change in radiation flux from zero sufficient to provide a steady state midscale reading. “Scattered radiation” means radiation that, during passage through matter, has been deviated in direction (See “Direct scattered radiation” ).
“Shutter” means a device attached to the tube housing assembly which can intercept the entire cross sectional area of the useful beam and which has a lead equivalency not less than that of the tube housing assembly.
“Single occupancy room” means a room which has walls on all sides (excluding the room entrance) of a minimum of seven (7) feet high that has an x-ray attenuation (for the x-ray beam in use at the facility) equivalent to at least two (2) thicknesses of one-half inches of gypsum wallboard which is occupied by one individual at a time. This only applies to rooms with dental intraoral or panoramic machines. “Source” means the focal spot of the x-ray tube.
“Source-image receptor distance (SID)” means the distance from the source to the center of the input surface of the image receptor.
“Spot check” means a procedure which is performed to assure that a previous calibration continues to be valid.
“Spot film” means a radiograph which is made during a fluoroscopic examination to permanently record conditions which exist during that fluoroscopic procedure. “Spot-film device” means a device intended to transport and/or position a radiographic image receptor between the x-ray source and fluoroscopic image receptor. It includes a device intended to hold a cassette over the input end of an image intensifier for the purpose of making a radiograph. “Source to skin distance (SSD)” means the distance between the source and the skin of the patient. “Stray radiation” means the sum of leakage and scattered radiation. “Technique chart” means a chart which specifies, for common examinations performed with a specific system, the following information:
(1) technique factors to be utilized versus patient's anatomical size;
(2) type and size of the film or film-screen combination to be used;
(3) type and focal distance of the grid to be used, if any; and (4) source to image receptor distance to be used.
“Technique factors” means the following conditions of operation:
(1) For capacitor energy storage equipment, peak tube potential in kV and quantity of charge in mAs;
(2) For field emission equipment rated for pulsed operation, peak tube potential in kV, and number of x- ray pulses;
(3) For CT x-ray systems designed for pulsed operation, peak tube potential in kV, scan time in seconds, and either tube current in mA, x-ray pulse width in seconds, and the number of x-ray pulses per scan, or the product of tube current, x-ray pulse width, and the number of x-ray pulses in mAs;
(4) For CT x-ray systems not designed for pulsed operation, peak tube potential in kV, and either tube current in mA and scan time in seconds, or the product of tube current and exposure time in mAs and the scan time when the scan time and exposure time are equivalent; and (5) For all other equipment, peak tube potential in kV, and either tube current in mA and exposure time in seconds, or the product of tube current and exposure time in mAs. “Termination of irradiation” means the stopping of irradiation in a fashion which will not permit continuance of irradiation without the resetting of operating conditions at the control panel. “Tomogram” means the depiction of the x-ray attenuation properties of a section through the body. “Traceable to a national standard” means that a quantity or a measurement has been compared to a national standard directly or indirectly through one or more intermediate steps and that all comparisons have been documented.
“Tube” means an x-ray tube, unless otherwise specified. “Tube housing assembly” means the tube housing with tube installed. It includes high-voltage and/or filament transformers and other appropriate elements when such are contained within the tube housing. “Tube rating chart” means the set of curves which specify the rated limits of operation of the tube in terms of the technique factors. These curves are typically displayed on a graph. “Useful beam” means the radiation emanating from the tube housing port or the radiation head and passing through the aperture of the beam limiting device when the exposure controls are in a mode to cause the system to produce radiation.
“Variable-aperture beam-limiting device” means a beam-limiting device which has capacity for stepless adjustment of the x-ray field size at a given SID.
“Visible area” means that portion of the input surface of the image receptor over which incident x-ray photons are producing a visible image.
“Wedge filter” means an added filter effecting continuous progressive attenuation on all or part of the useful beam.
“X-rayexposure control” means a device, switch, button or other similar means by which an operator initiates and/or terminates the radiation exposure. The x-ray exposure control may include such associated equipment as timers and back-up timers.
“X-ray equipment” means an x-ray system, subsystem, or component thereof. Types of x-ray equipment are as follows:
(1) “Mobile x-ray equipment” means x-ray equipment mounted on a permanent base with wheels and/or casters for moving while completely assembled.
(2) “Portable x-ray equipment” means x-ray equipment designed to be hand-carried.
(3) “Stationary x-ray equipment” means x-ray equipment which is installed in a fixed location. “X-ray field” means that area of the intersection of the useful beam and any one of the set of planes parallel to and including the plane of the image receptor, whose perimeter is the locus of points at which the exposure rate is one-fourth of the maximum in the intersection. “X-ray high-voltage generator” means a device which transforms electrical energy from the potential supplied by the x-ray control to the tube operating potential. The device may also include means for transforming alternating current to direct current, filament transformers for the x-ray tube(s), high-voltage switches, electrical protective devices, and other appropriate elements. “X-ray subsystem” means any combination of two or more components of an x-ray system. “X-ray table” means a patient support device with its patient support structure (tabletop) interposed between the patient and the image receptor during radiography and/or above table fluoroscopy. This includes, but is not limited to, any stretcher equipped with a radiolucent panel and any table equipped with a cassette tray (or bucky), cassette tunnel, image intensifier, or spot-film device beneath the tabletop. “X-ray tube” means any electron tube which is designed to be used primarily for the production of x- rays.
General Regulatory Provisions RH 6.3 General Requirements .
Effective July 1, 1995, all human use radiation machines used in Colorado shall meet the Federal Performance Standards, Subchapter J - Radiological Health, 21 CFR 1020.30 through 1020.33, effective April 1, 1997. The Department may grant exemptions to machines manufactured prior to August 4, 1974, provided the registrant can demonstrate that the exemption will not result in undue risk from excessive exposure and will benefit the patient.
6.3.1 Administrative Controls .
6.3.1.1 Registrant. The registrant shall be responsible for directing the operation of the x-ray system(s) under his administrative control. The registrant or the registrant's agent shall assure that the requirements of RH 6.3.1 are met in the operation of the x-ray system(s), including the use of licensed/certified/registered persons or companies (providers) to provide services to the facility. Such services include the operation of x-ray equipment, interpretation of exams, inspection of x- ray machines and facilities, installation, service and/or calibration of x-ray machines.
exposure required to produce images of acceptable diagnostic quality.
panel;
calibrations, maintenance, and modifications performed on the x-ray system(s) with the names of persons who performed such services;
adopt a continuous, documented sensitometric quality control program.
method used to monitor and/or determine processing time.
constructed as to exclude light from the darkroom when cassettes are placed in or removed from the boxes, and shall incorporate adequate shielding from stray radiation to prevent exposure of undeveloped film.
6.3.2 Plan Review and Shielding Design.
6.3.2.1 Prior to the construction of a new x-ray facility, the floor plans and equipment arrangement shall be submitted to a qualified expert for the determination of shielding requirements. Prior to the modification or renovation of an existing x-ray facility, or installation of a new x-ray machine in an existing x-ray facility, the plans and equipment arrangements shall be submitted to a qualified expert for determination of shielding requirements when there is a change in primary beam orientation, or a change in primary shielding due to the modification or renovation of a facility, or there is a projected increase in the x-ray workload from that which was used for the original x-ray shielding design. In such cases shielding shall meet the criteria in Appendix B and the recommendations of the qualified expert. The required information is denoted in Appendices A and B of this Part.
6.3.2.2 The review of such plans, and determination of shielding requirements, shall not preclude the requirement of additional modifications should a subsequent analysis of operating conditions indicate the possibility of an individual receiving a dose in excess of the limits prescribed in RH 4.6, 4.12, 4.13, and 4.14 of these Regulations.
Diagnostic X-Ray Systems RH 6.4 General Requirements for All Diagnostic X-Ray Systems. In addition to other requirements of this Part, all diagnostic x-ray systems shall meet the following requirements:
6.4.1 Warning Label.
The control panel containing the main power switch shall bear this or an equivalent warning statement, 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.”
6.4.2 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.
6.4.3 Leakage Radiation from the Diagnostic Source Assembly.
The leakage radiation from the diagnostic source assembly measured at a distance of 1 meter in any direction from the source shall not exceed 25.8 µC/kg (100 milliroentgen) in one hour when the x-ray tube is operated at its leakage technique factors. Compliance shall be determined by measurements averaged over an area of 100 square centimeters with no linear dimension greater than 20 centimeters.
6.4.4 Radiation from Components Other Than the Diagnostic Source Assembly.
The radiation emitted by a component other than the diagnostic source assembly shall not exceed 0.516 µC/kg (2 milliroentgen) in one hour at 5 centimeters 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 100 square centimeters with no linear dimension greater than 20 centimeters.
6.4.5 Beam Quality.
6.4.5.1 Half-Value Layer .
. . Other Systems Dental Systems Below 50 30 0.3 1.5 . 40 0.4 1.5 . 49 0.5 1.5 50 to 70 50 1.2 1.5 . 60 1.3 1.5 . 70 1.5 1.5 Above 70 71 2.1 2.1 . 80 2.3 2.3 . 90 2.5 2.5 . 100 2.7 2.7 . 110 3.0 3.0 . 120 3.2 3.2 . 140 3.8 3.8 . 150 4.1 4.1
Table II - Filtration Required vs. Operating Voltage Operating Voltage Total Filtration Other Systems Dental Systems
Below 50 . . . . . . . . . . . . . . . . . . . . . 0.5 1.5 .
50 - 70 . . . . . . . . . . . . . . . . . . . . . 1.5 1.5 .
Above 70 . . . . . . . . . . . . . . . . . . . . . 2.5 2.5 .
6.4.5.2 Filtration Controls. For x-ray systems which have variable kVp and variable filtration for the useful beam, a device shall link the kVp selector with the filter(s) and shall prevent an exposure unless the minimum amount of filtration required by RH 6.4.5.1 is in the useful beam for the given kVp which has been selected.
6.4.6 Multiple Tubes.
Where two or more radiographic tubes are controlled by one exposure switch, the tube or tubes which have been selected shall be clearly indicated prior to initiation of the exposure. This indication shall be both on the x-ray control and at or near the tube housing assembly which has been selected.
6.4.7 Mechanical Support of Tube Head.
The 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.
6.4.7.1 Locks . All position locking, holding, and centering devices on x-ray systems components and system shall function as designed.
6.4.8 Technique Indicators .
6.4.8.1 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.
6.4.8.2 The requirement of RH 6.4.8.1 may be met by permanent markings on equipment having fixed technique factors.
RH 6.5 Fluoroscopic X-Ray Systems Except for Computed Tomography X-Ray Systems. All fluoroscopic x-ray systems shall meet the following requirements:
6.5.1 Limitation of Useful Beam.
6.5.1.1 Primary Barrier .
6.5.1.2 X-Ray Field.
between the image receptor and beam axis is variable, means shall be provided to indicate when the axis of the x-ray beam is perpendicular to the plane of the image receptor; and the entire cross section of the useful beam shall be intercepted by the primary protective barrier at any SID.
perpendicular to the plane of the image receptor. Measurement shall be made in perpendicular directions corresponding to the vertical and horizontal directions on the video/tv monitor image. For collimating systems which are not circular, measurement shall be made along the directions closest to the vertical and horizontal direction on the video monitor image yielding the smallest dimension in each direction.
FOR X-RAY FIELD LIMITATION SYSTEM FAILURE
6.5.2 Activation of the Fluoroscopic Tube.
X-ray production in the fluoroscopic mode shall be controlled by a device which requires continuous pressure by the operator for the entire time of any exposure. When recording serial fluoroscopic images, the operator shall be able to terminate the x-ray exposure(s) at any time.
6.5.3 Exposure Rate Limits.
6.5.3.1 Entrance Exposure Rate Limits for Fluoroscopic Equipment Manufactured Before May 19, 1995 .
6.5.3.2 Entrance Exposure Rate Limits For Fluoroscopic Equipment Manufactured On and After May 19, 1995.
6.5.3.3 Compliance with the requirements of RH 6.5.3 shall be determined as follows:
follows:
the requirements of RH 6.5.3.3;
x-ray system;
control shall have the beam collimated to the size of the detector and have sufficient material placed in the useful beam to intercept the entire beam so that output of the machine is a maximum for the x-ray system; and 6.5.3.3.5.2.4 X-ray system(s) that do not incorporate an automatic exposure rate control shall utilize the maximum milliamperage typical of the clinical use of the x-ray system. 2 2 Materials should be placed in the useful beam when conducting these periodic measurements to protect the imaging system.
6.5.4 Barrier Transmitted Radiation Rate Limits .
6.5.4.1 The exposure rate due to transmission through the primary protective barrier with the attenuation block in the useful beam, combined with radiation from the image intensifier, if provided, shall not exceed 0.516 µC/kg per hour (2 milliroentgen) at 10 centimeters from any accessible surface of the fluoroscopic imaging assembly beyond the plane of the image receptor for each roentgen per minute of entrance exposure rate.
6.5.4.2 Measuring Compliance of Barrier Transmission.
6.5.5 Indication of Potential and Current.
During fluoroscopy and cinefluorography the kV and the mA shall be continuously indicated on certified units.
6.5.6 Source-to-Skin Distance.
The SSD shall not be less than:
6.5.6.1 38 centimeters on stationary fluoroscopes installed after September 1, 1992, 6.5.6.2 35.5 centimeters on stationary fluoroscopes which were in operation on or before September 1, 1992,
6.5.6.3 30 centimeters on all mobile fluoroscopes;
6.5.6.4 20 centimeters for fluoroscopes used for specific surgical application. The written safety procedures must provide precautionary measures to be adhered to during the use of these systems; and
6.5.6.5 9 centimeters for mini c-arms.
6.5.7 Fluoroscopic Timer.
6.5.7.1 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 (5) minutes without resetting.
6.5.7.2 A signal to the operator 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
6.5.8 Control of Scattered Radiation.
6.5.8.1 Conventional fluoroscopic table designs when combined with procedures utilized shall be such that no unprotected part of any staff or ancillary individual's body shall be exposed to unattenuated scattered radiation which originates from under the table. The attenuation required shall be not less than 0.25 millimeter lead equivalent.
6.5.8.2 Equipment configuration when combined with procedures shall be such that no portion of any staff or ancillary individual's body, except the extremities or head, shall be exposed to the unattenuated scattered radiation emanating from above the tabletop unless that individual:
6.5.8.3 The Department may grant exemptions to RH 6.5.8.2 where a sterile field will not permit the use of the normal protective barriers. Where the use of prefitted sterilized covers for the barriers is practical, the Department shall not permit such exemption.
6.5.8.4 The Department may grant exemptions to RH 6.5.8.2 when the use of drapes or self-supporting curtains are contra indicated and the diagnosis could be compromised.
6.5.9 Radiation Therapy Simulation Systems.
Radiation therapy simulation systems shall be exempt from all the requirements of RH 6.5.1, 6.5.3, 6.5.4, and 6.5.7 provided that:
6.5.9.1 such systems are designed and used in such a manner that no individual other than the patient, required staff and ancillary personnel are in the x-ray room during periods of time when the system is producing x-rays; and 6.5.9.2 systems which do not meet the requirements of RH 6.5.7 are provided with a means of indicating the cumulative time that an individual patient has been exposed to x-rays. Procedures shall require in such cases that the timer be reset between examinations. RH 6.6 Radiographic Systems Other Than Fluoroscopic, Dental Intraoral, Veterinary, Computed Tomography, or Mammography X-Ray Systems.
6.6.1 Beam Limitation.
The useful beam shall be limited to the area of clinical interest.
6.6.1.1 General Purpose Stationary and Mobile X-Ray Systems .
6.6.1.2 Additional Requirements for Stationary General Purpose X-Ray Systems. In addition to the requirements of RH 6.6.1.1, stationary general purpose x-ray systems, shall meet the following requirements:
6.6.1.3 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 two (2) percent 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.
6.6.1.4 X-Ray Systems Other Than Those Described in RH 6.6.1.1, 6.6.1.2 and 6.6.1.3.
6.6.2 Radiation Exposure Control Devices.
6.6.2.1 Timers. 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. 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.
6.6.2.2 X-Ray Control.
6.6.2.3 Automatic Exposure Controls. When an automatic exposure control is provided:
6.6.2.4 Timer Reproducibility. With a timer setting of 0.5 seconds or less, the average exposure period (T ) shall be greater than or equal to five (5) times the maximum exposure period (T ) minus avg max the minimum exposure period (T ) when four (4) timer tests exposures are performed: min T ≥ 5(T - T ).
6.6.3 Source-to-Skin Distance.
All mobile or portable radiographic systems shall be provided with means to limit the source-to-skin distance to equal to or greater than 30 centimeters.
6.6.4 Exposure Reproducibility.
When all technique factors are held constant, including control panel selections associated with automatic exposure control systems, the coefficient of variation of exposure for both manual and automatic exposure control systems shall not exceed 0.05. The facility registrant may request an exemption for any machines manufactured prior to 1974, which cannot meet this requirement. The exemption request must verify that this exposure reproducibility variation will not result in unnecessary patient radiation exposure due to the need for repeat examinations.
6.6.5 Radiation from Capacitor Energy Storage Equipment in Standby Status.
Radiation emitted from the x-ray tube when the exposure switch or timer is not activated shall not exceed a rate of 0.516 µC/kg (2 milliroentgen) per hour at 5 centimeters from any accessible surface of the diagnostic source assembly, with the beam-limiting device fully open.
6.6.6 Additional Requirements Applicable to Certified Systems Only.
Diagnostic x-ray systems incorporating one or more certified component(s) shall be required to comply with the following additional requirement(s) which relate to that certified component(s).
6.6.6.1 Linearity. When the equipment allows a choice of x-ray tube current or mAs settings for any fixed x-ray tube potential within the range of 40 to 100 percent of the maximum rating, the average ratio of exposure to the indicated milliampere-seconds product obtained at any two (2) consecutive tube current or mAs settings shall not differ by more than 0.10 times their sum: | 1 - 2 | ≤ 0.10 ( 1 + 2 ), where 1 and 2 are the average mR/mAs (microcoulomb/kilogram per mAs) values obtained at each of two (2) consecutive tube current settings or at two settings differing by no more than a factor of two (2) when the mAs selector provides continuous selection.
6.6.6.2 Accuracy. Deviation of technique factors from indicated values shall not exceed the limits specified for that system by its manufacturer. If manufacturer specifications are not available, the following criteria shall be used:
6.6.6.3 Beam Limitation for Stationary and Mobile General Purpose X-Ray Systems .
Column 1 Column 2 Ambient Light Net Minimum Light Illuminance Illuminance Above Ambient 5 to 25 lux 25 lux 26 to 50 lux 50 lux 51 to 75 lux 75 lux 76 to 100 lux 100 lux 101 to 159 lux 100 lux
6.6.6.4 Beam Limitation for Portable X-Ray Systems. Beam limitation for portable x-ray systems shall meet the beam limitation requirements of RH 6.6.1.1 and 6.6.6.3.
6.6.6.5 Positive Beam Limitation (PBL).
labeled as follows:
FOR X-RAY FIELD LIMITATION SYSTEM FAILURE
6.6.6.6 Timers. Except for dental panoramic systems, termination of exposure shall cause automatic resetting of the timer to its initial setting or to “zero” . RH 6.7 Intraoral Dental Radiographic Systems.
In addition to the provisions of RH 6.3 and 6.4, the requirements of RH 6.7 apply to x-ray equipment and associated facilities used for dental radiography. Requirements for extra-oral dental radiographic systems are covered in RH 6.6.
6.7.1 Source-to-Skin Distance (SSD).
X-ray systems designed for use with an intraoral image receptor shall be provided with means to limit SSD, to not less than:
6.7.1.1 18 centimeters if operable above 50 kVp, or
6.7.1.2 10 centimeters if not operable above 50 kVp.
6.7.2 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:
6.7.2.1 if the minimum SSD is 18 centimeters or more, the x-ray field, at the minimum SSD, shall be containable in a circle having a diameter of no more than 7 centimeters; and 6.7.2.2 if the minimum SSD is less than 18 centimeters, the x-ray field, at the minimum SSD, shall be containable in a circle having a diameter of no more than 6 centimeters.
6.7.3 Timers.
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. In addition:
6.7.3.1 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.
6.7.3.2 Termination of exposure shall cause automatic resetting of the timer to its initial setting or to “zero” .
6.7.3.3 Timer Reproducibility. With a timer setting of 0.5 seconds or less, the average exposure period (T ) shall be greater than or equal to five (5) times the maximum exposure period (T ) minus avg max the minimum exposure period (T ) when four (4) timer tests are performed: min T ≥ 5(T - T ).
6.7.4 X-Ray Control .
6.7.4.1 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 one-half (0.5) second or less.
6.7.4.2 Each x-ray control shall be located in such a way as to meet the following requirements:
6.7.4.3 The x-ray control shall provide visual indication observable at or from the operator's protected position whenever x-rays are produced.
6.7.5 Exposure reproducibility.
The estimated coefficient of variation of radiation exposure shall be no greater than 0.05, for any specific combination of selected technique factors.
6.7.6 Linearity.
When the equipment allows a choice of x-ray tube current settings and is operated on a power supply as specified by the manufacturer in accordance with the requirements of applicable Federal standards, for any fixed x-ray tube potential within the range of 40 to 100 percent of the maximum rating, the average ratios of exposure to the indicated milliampere-seconds product obtained at any two (2) consecutive tube current or mAs settings shall not differ by more than 0.10 times their sum: | 1 - 2 | ≤ 0.10 ( 1 + 2 ), where 1 and 2 are the average mR/mAs values obtained at each of two (2) consecutive tube current or mAs settings.
6.7.7 Accuracy.
Deviation of technique factors from indicated values shall not exceed the limits specified for that system by its manufacturer. If those are not available, accuracy of all exposure factors shall be within ten (10) percent of the selected factor(s).
6.7.8 Beam Quality.
All certified dental x-ray systems manufactured on and after December 1, 1980, shall have a minimum half-value layer not less than 1.5 millimeters aluminum equivalent Systems operating above 70 kVp are subject to the filtration requirements of RH 6.4.5.1.
6.7.9 Administrative Controls.
6.7.9.1 Patient and film holding devices shall be used when the techniques permit.
6.7.9.2 The tube housing and the PID shall not be hand-held during an exposure.
6.7.9.3 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.
6.7.9.4 Dental fluoroscopy without image intensification shall not be used.
Other Diagnostic X-Ray Systems RH 6.8 Veterinary Medicine Radiographic Installations.
6.8.1 Equipment.
6.8.1.1 The protective tube housing shall be equivalent to the requirements of RH 6.4.3.
6.8.1.2 Diaphragms or cones shall be provided for collimating the useful beam to the area of clinical interest and shall provide the same degree of protection as is required of the housing.
6.8.1.3 The total filtration permanently in the useful beam shall meet the requirement of RH 6.4.5.1.
6.8.1.4 Exposure Reproducibility. The coefficient of variation of exposure shall not exceed 0.10 when all technique factors are held constant.
6.8.1.5 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 5 (five) percent 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.
6.8.1.6 A device shall be provided to terminate the exposure after a preset time or exposure.
6.8.1.7 A dead-man type of exposure switch shall be provided, together with an electrical cord of sufficient length, so that the operator can stand out of the useful beam.
6.8.2 Structural Shielding.
All wall, ceiling, and floor areas shall be equivalent to or provided with applicable protective barriers to assure compliance with RH 4.6, 4.12, 4.13, and 4.14 of these Regulations.
6.8.2.1 Veterinary facilities are exempt from the requirements of Appendix B, provided that the operator is adequately protected by distance and/or shielding.
6.8.3 Operating Procedures .
6.8.3.1 Whenever possible, the operator shall stand well away from the useful beam and the animal during radiographic exposures.
6.8.3.2 No individual, other than the operator, shall be in the x-ray room while exposures are being made, unless such individual's assistance is required and the person is adequately protected by shielding and/or distance.
6.8.3.3 When an animal must be held in position during radiography, mechanical supporting or restraining devices should be used. If the animal must be held by an individual, that individual shall be protected with appropriate shielding devices, such as protective gloves and apron, and he/she shall be so positioned that no part of his/her body will be struck by the useful beam. The exposure of any individual used for this purpose shall be maintained below the limits specified in RH 4.6, 4.12, and 4.13.
6.8.3.4 No human shall hold the image receptor during radiography unless that individual is protected with appropriate shielding devices, such as protective gloves and apron, and that any part of his/her body struck by the useful beam shall be monitored. The exposure of any individual used for this purpose shall be maintained below the limits specified in RH 4.6, 4.12, and 4.13. RH 6.9 Computed Tomography X-Ray Systems.
6.9.1 Definitions.
In addition to the definitions provided in RH 1.4 and 6.2 of these Regulations, the following definitions shall be applicable to RH 6.9:
This definition assumes that the dose profile is centered around z=0 and that, for a multiple tomogram system, the scan increment between adjacent scans is nT. “Contrast scale (CS)” means the change in the linear attenuation coefficient per CTN relative to water, that is:
w (CTN) = CTN of the material of interest.
x (CTN) = CTN of water.
w “CT conditions of operation” means all selectable parameters governing the operation of a CT x- ray system including, but not limited to, nominal tomographic section thickness, filtration, and the technique factors as defined in RH 6.2.
“CT gantry” means the tube housing assemblies, beam-limiting devices, detectors, and the supporting structures and frames which hold these components. “CT number (CTN)” means the number used to represent the x-ray attenuation associated with each elemental area of the CT image.
w “Dose profile” means the dose as a function of position along a line. “Elemental area” means the smallest area within a tomogram for which the x-ray attenuation properties of a body are depicted. (See also “Picture element” ).
“Multiple tomogram system” means a computed tomography x-ray system which obtains x-ray transmission data simultaneously during a single scan to produce more than one tomogram. “Noise” means the standard deviation of the fluctuations in CTN expressed as a percentage of the attenuation coefficient of water. Its estimate (S ) is calculated using the following expression: n where:
“Nominal tomographic section thickness” means the full width at half-maximum of the sensitivity profile taken at the center of the cross-sectional volume over which x-ray transmission data are collected.
“Picture element” means an elemental area of a tomogram. “Reference plane” means a plane which is displaced from and parallel to the tomographic plane.
“Scan” means the complete process of collecting x-ray transmission data for the production of a tomogram. Data can be collected simultaneously during a single scan for the production of one or more tomograms.
“Scan increment” means the amount of relative displacement of the patient with respect to the CT x-ray system between successive scans measured along the direction of such displacement. “Scan sequence” means a pre-selected set of two or more scans performed consecutively under pre-selected CT conditions of operation.
“Scan time” means the period of time between the beginning and end of x-ray transmission data accumulation for a single scan.
“Single tomogram system” means a CT x-ray system which obtains x-ray transmission data during a scan to produce a single tomogram.
“Tomographic plane” means that geometric plane which is identified as corresponding to the output tomogram.
“Tomographic section” means the volume of an object whose x-ray attenuation properties are imaged in a tomogram.
6.9.2 Requirements for Equipment.
6.9.2.1 Termination of Exposure.
6.9.2.1.1 Means shall be provided to terminate the x-ray exposure automatically by either de-energizing 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 percent of its preset value through the use of either a backup timer or devices which monitor equipment function.
6.9.2.1.2 A visible signal shall indicate when the x-ray exposure has been terminated through the means required by RH 6.9.2.1.1.
6.9.2.1.3 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 one-half second duration.
6.9.2.2 Tomographic Plane Indication and Alignment.
6.9.2.2.1 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.
6.9.2.2.2 For any multiple tomogram system, means shall be provided to permit visual determination of the location of a reference plane. This reference plane can be offset from the location of the tomographic planes.
6.9.2.2.3 If a device using a light source is used to satisfy RH 6.9.2.2.1 or 6.9.2.2.2, 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 (46 foot candles).
6.9.2.3 Beam-On and Shutter Status Indicators and Control Switches.
6.9.2.3.1 The CT x-ray control and gantry shall provide visual indication whenever x-rays are produced and, if applicable, whether the shutter is open or closed.
6.9.2.3.2 Each emergency button or switch shall be clearly labeled as to its function.
6.9.2.4 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 shall be 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.
6.9.2.5 Extraneous Radiation.
When data are not being collected for image production, the radiation adjacent to the tube port shall not exceed that permitted by RH 6.4.3.
6.9.2.6 Additional Requirements Applicable to CT X-Ray Systems Containing a Gantry Manufactured After September 2, 1992.
6.9.2.6.1 The total error in the indicated location of the tomographic plane or reference plane shall not exceed 5 millimeters.
6.9.2.6.2 If the x-ray production period is less than one-half second, the indication of x-ray production shall be actuated for at least one-half 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.
6.9.2.6.3 The deviation of indicated scan increment versus actual increment shall not exceed plus or minus 1 millimeter with any mass from 0 to 100 kilograms resting on the support device. The patient support device shall be incremented from a typical starting position to the maximum incremented distance or 30 centimeters, whichever is less, and then returned to the starting position. Measurement of actual versus indicated scan increment may be taken anywhere along this travel.
6.9.2.6.4 Premature termination of the x-ray exposure by the operator shall necessitate resetting of the CT conditions of operation prior to the initiation of another scan.
6.9.3 Facility Design Requirements.
6.9.3.1 Aural Communication.
Provision shall be made for two-way aural communication between the patient and the operator at the control panel.
6.9.3.2 Viewing Systems.
6.9.3.2.1 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.
6.9.3.2.2 Patient scanning shall be allowed only when a viewing system is available and in use.
6.9.4 Surveys, Evaluations, Calibrations, Spot Checks, and Operating Procedures.
6.9.4.1 Surveys and Evaluations.
6.9.4.1.1 All CT x-ray systems installed after September 1, 1992 and those systems not previously surveyed shall have a shielding survey made by, or under the direction of, a qualified expert. In addition, such surveys shall be done after any change in the facility or equipment which might cause a significant increase in radiation hazard.
6.9.4.1.2 The registrant shall obtain a written report of the survey from the qualified expert, and a copy of the report shall be made available to the Department upon request.
6.9.4.1.3 Notwithstanding the provisions of RH 2.5.1.2, CT x-ray systems that have undergone a tube change within 12 months of the last annual evaluation do not require a complete calibration provided that the CT x-ray system operation after the tube change meets the criteria established by the qualified expert. The certification evaluation (CE) need not be performed each time an x- ray tube is replaced. However, each CT system shall receive a CE at least within one year of the previous CE.
6.9.4.2 Radiation Calibrations.
6.9.4.2.1 The calibration of the radiation output of the CT x-ray system shall be performed by, or under the direction of, a qualified expert who is physically present at the facility during such calibration.
6.9.4.2.2 The calibration of a CT x-ray system shall be performed at intervals, not exceeding one year, specified by a qualified expert.
6.9.4.2.3 The calibration of the radiation output of a CT x-ray system shall be performed with a calibrated dosimetry system. The calibration of such system shall be traceable to a national standard. The dosimetry system shall have been calibrated within the preceding two (2) years.
6.9.4.2.4 CT dosimetry phantom(s) shall be used in determining the radiation output of a CT x-ray system. Such phantom(s) shall meet the following specifications and conditions of use:
6.9.4.2.5 The calibration shall be required for each common type of head, body, or whole-body scan performed at the facility.
6.9.4.2.6 Calibration shall meet the following requirements:
4 For the purpose of determining the CTDI, the manufacturer's statement as to the nominal tomographic section thickness for that particular system may be utilized.
6.9.4.2.7 Calibration procedures shall be in writing. Records of calibrations performed shall be maintained for a period of three (3) years for inspection by the Department.
6.9.4.3 Spot Checks.
6.9.4.3.1 The spot-check procedures shall be in writing and shall have been developed by a qualified expert.
6.9.4.3.2 The spot-check procedures shall incorporate the use of a CT performance phantoms which has a capability of providing an indication of contrast scale, noise, nominal tomographic section thickness, the resolution capability of the system for low and high contrast objects, and measuring the mean CTN for water or other reference material.
6.9.4.3.3 All spot checks shall be included in the calibration required by RH 6.9.4.2 and at time intervals and under system conditions specified by a qualified expert.
6.9.4.3.4 Spot checks shall include acquisition of images obtained with the CT performance phantom(s) using the same processing mode and CT conditions of operation as are used to perform calibrations required by RH 6.9.4.2. The images shall be retained, until a new calibration is performed, as follows:
6.9.4.3.5 Written records of the spot checks performed shall be maintained for inspection by the Department.
6.9.4.4 Operating Procedures
6.9.4.4.1 The CT x-ray system shall not be operated except by an individual who has been specifically trained in its operation.
6.9.4.4.2 Information shall be available at the control panel regarding the operation of the system. Information regarding calibration of the system shall be readily available. Such information shall include the following:
6.9.4.4.3 If the calibration or spot check of the CT x-ray system identifies that a system operating parameter has exceeded a tolerance established by the qualified expert, use of the CT x-ray system on patients shall be limited to those uses permitted by established written instructions of the qualified expert.
RH 6.10 Mammography.
6.10.1 Definitions.
“Continuing education unit (CEU)” means one contact hour of training or education, which is documentable.
“Established operating level” means the value of a particular quality assurance parameter that has been established as an acceptable normal level by the facility's quality assurance program. “Facility” means a hospital, outpatient Department, clinic, radiology practice, mobile unit, office of a physician, or other facility that conducts mammography activities, including the following: operation of equipment to produce a mammogram, initial interpretation of the mammogram, and maintaining viewing conditions for that interpretation.
“Laterality” means the designation of either the right or left breast. “Mammogram” means a radiographic image produced through mammography. “Mammography” means radiography of the breast, but for the purposes of this Part, does not include: radiography of the breast performed during invasive interventions for localization or biopsy procedures; or radiography of the breast performed with an investigational mammography device as part of a scientific study conducted.
“Mammography phantom” means a test object used to simulate radiographic characteristics of compressed breast tissue and containing components that radiographically model aspects of breast disease and cancer. For the purpose of this section, phantom means mammography phantom. “Mammography medical outcomes audit” means a systematic collection of mammography results and the comparison of those results with outcomes data.
“Patient” means any individual who undergoes a mammography evaluation in a facility, regardless of whether the person is referred by a physician or is self-referred. “Standard breast” means a 4.2 centimeter (cm) thick compressed breast consisting of fifty(50) percent glandular and fifty (50) percent adipose tissue.
6.10.2 Quality Standards.
6.10.2.1 Personnel.
6.10.2.1.1 Radiologic Technologists. All mammographic examinations shall be performed by a person who meets the following requirements.
6.10.2.1.2 Qualified Inspectors. All qualified inspectors conducting mammography facility and x-ray machine evaluations shall meet the requirements of Appendix B, c. of Part 2.
6.10.2.2 Equipment.
Only x-ray systems meeting the following standards shall be used:
6.10.2.2.1 System Design. The x-ray system shall be specifically designed for mammography; and 6.10.2.2.2 Image Receptor Sizes. Systems using screen-film image receptors shall provide, at a minimum, for operation with image receptors of 18 x 24 centimeters (cm) and 24 x 30 cm. The image receptors shall be equipped with moving grids matched to all image receptor sizes provided. Systems used for magnification procedures shall be capable of operation with the grid removed from between the source and image receptor;
6.10.2.2.3 Beam Limitation and Light Fields. All systems shall have beam-limiting devices that allow the useful beam to extend to or beyond the chest wall edge of the image receptor and shall meet the requirement of RH 6.10.2.6.8. When a light localizer is used to define the x-ray field, it shall meet the requirement of RH 6.6.6.3.2.
6.10.2.2.4 Magnification. Systems used to perform noninterventional problem solving procedures shall have radiographic magnification capability available for use by the operator. Systems used for magnification procedures shall provide, as a minimum, at least one magnification value within the range of 1.4 to 2.0.
6.10.2.2.5 Focal Spot Selection. When more than one focal spot is provided, the system shall indicate, prior to the exposure, which focal spot is selected. When more than one target material is provided, the system shall indicate, prior to the exposure, the preselected target material. When the target material and/or focal spot is automatically selected by the machine, the system shall display, after the exposure, the used target material and/or focal spot.
6.10.2.2.6 Compression . All mammography systems shall incorporate a compression device.
6.10.2.2.7 Technique Factor Selection and Display. Manual selection of milliampere seconds (mAs) or at least one of its component parts [milliampere (mA) and time] shall be available.
6.10.2.2.8 Automatic Exposure Control. All systems shall provide an AEC mode that is operable in all combinations of equipment configuration provided, i.e., grid, nongrid, magnification, non- magnification, and various target-filter combinations.
6.10.2.2.9 X-ray Film and Intensifying Screens. The registrant shall use x-ray film and intensifying screens that have been designated by the manufacturers as appropriate and screen/film compatible for mammography.
6.10.2.2.10 Film Processing Solutions. The registrant shall use chemical solutions that are capable of developing the mammography films in a manner equivalent to the minimum requirements specified by the film manufacturer.
6.10.2.2.11 Lighting. Hot lights, capable of producing light levels greater than that provided by the view box, shall be available for use.
6.10.2.2.12 Film Masking Devices. The registrant shall ensure that film masking devices that can limit the illuminated area to a region equal to or smaller than the exposed portion of the film are available and used.
6.10.2.2.13 Viewboxes used for interpreting mammograms and clinical quality review by the technologist shall be capable of producing a luminance of at least 3,000 candela per square meter (cd/m ).
6.10.2.3 Medical Records And Mammography Reports.
6.10.2.3.1 Contents and Terminology. The registrant shall prepare a written report of the results of each mammography examination performed. The report shall include: the name of the patient and an additional patient identifier; the date of the examination; the name of the interpreting physician who interpreted the mammogram; and the overall final assessment of findings.
6.10.2.3.2 Communication of Mammography Results to the Patient. The registrant shall maintain a system to ensure that the results of each mammography examination are communicated to the patient in a timely manner.
6.10.2.3.3 Communication of Mammography Results to Health Care Providers. When the patient has named a referring health care provider, the registrants shall provide a written report of the mammography examination, within thirty (30) days from the date of the exam, to that provider.
6.10.2.3.4 Record Keeping. The registrant shall maintain mammography films and reports in a permanent medical record of the patient for a period of not less than five (5) years, or not less than ten (10) years if no additional mammograms of the patient are performed at the facility.
6.10.2.3.5 Mammographic Image Identification. Each mammography image shall clearly indicate the patient's name and an additional patient identifier; the date of the examination; the view and laterality; the facility name and location; the technologist identification; the cassette/screen identification; and the mammography unit.
6.10.2.4 Quality Assurance - General Requirements.
The registrant shall establish and maintain a quality assurance program to ensure the safety, reliability, clarity, and accuracy of mammography services performed at the facility.
6.10.2.5 Quality Assurance - Quality Control of Mammography Operations.
6.10.2.5.1 All tests specified in RH 6.10.2.5 shall be performed by a qualified mammographer or provisional mammographer.
6.10.2.5.2 Daily Quality Control Tests. Film processors used to develop mammograms shall be adjusted and maintained to meet the technical development specifications for the mammography film in
6.10.2.5.3 Weekly Quality Control Tests. Facilities with screen-film systems shall perform an image quality evaluation test, using an FDA-approved phantom, at least weekly. The test shall include the following assessment:
6.10.2.5.4 Quarterly Quality Control Tests. Facilities with screen-film systems shall perform the following tests at least quarterly:
6.10.2.5.5 Semiannual Quality Control Tests. Facilities with screen-film systems shall perform the following tests at least semiannually:
6.10.2.6 Quality Assurance - Facility and Equipment Evaluation.
Facilities with screen-film systems shall perform the following tests at least annually.
6.10.2.6.1 All tests specified in RH 6.10.2.6 shall be performed by a mammography approved qualified inspector.
6.10.2.6.2 Automatic Exposure Control Performance. The AEC shall be capable of maintaining film optical density within + or - 0.30 of the mean OD when thickness of a homogeneous material is varied over a range of 2 to 6 cm and the kVp is varied appropriately for such thicknesses over the kVp range used clinically. If this requirement cannot be met, a technique chart shall be developed showing appropriate techniques (kVp and density control settings) for different breast thicknesses and compositions that must be used so that an OD within + or - 0.30 of the average under phototimed conditions can be produced.
6.10.2.6.3 kVp Accuracy and Reproducibility. The kVp shall be accurate within + or - five (5) percent of the indicated kVp at:
6.10.2.6.4 Focal Spot Condition. Focal spot condition shall be evaluated either by determining system resolution or by measuring focal spot dimensions. After October 28, 2002, facilities shall evaluate focal spot condition only by determining the system resolution.
6.10.2.6.5 Beam Quality and Half-value Layer (HVL ). The HVL shall meet the following specifications for minimum HVL.
6.10.2.6.6 Breast Entrance Air Kerma and AEC Reproducibility. The coefficient of variation for both air kerma and mAs shall not exceed 0.05.
6.10.2.6.7 Dosimetry. The average glandular dose delivered during a single cranio-caudal view of an FDA-accepted phantom simulating a standard breast, using the clinical technique factors and conditions for that phantom, shall not exceed 3.0 milligray (0.3 rad) per exposure.
6.10.2.6.8 X-ray Field/Light Field/Image Receptor/Compression Alignment. All systems shall have beam -limiting devices that allow the useful x-ray beam to extend to or beyond the edges of the image receptor but by no more than two (2) percent of the SID at the chest wall side.
6.10.2.6.9 Uniformity of Screen Speed. Uniformity of screen speed of all the cassettes shall be tested and the difference between the maximum and minimum optical densities shall not exceed 0.3. Screen artifacts shall also be evaluated during this test.
6.10.2.6.10 System Artifacts. System artifacts shall be performed for all cassettes sizes using a grid appropriate for the cassette size being tested. System artifacts shall also be evaluated for all available focal spot sizes and target filter combinations used clinically.
6.10.2.6.11 Radiation Output. The system shall be capable of producing a minimum output of 4.5 mGy air kerma per second (513 milliroentgen per second) when operating at 28 kVp in the moly/moly mode at any SID where the system is designed to operate and when measured by a detector with its center located 4.5 cm above the breast support surface with the compression paddle in place as clinically used. After October 28, 2002, the system, under the same measuring conditions shall be capable of producing a minimum output of 7.0 mGy air kerma per second (800 milli roentgen per second).
6.10.2.6.12 Decompression. If the system is equipped with a provision for automatic decompression after completion of an exposure or interruption of power to the system, the system shall be tested to confirm that it provides:
6.10.2.7 Additional Mammography Equipment Evaluations.
An evaluation of mammography units or image processors shall be conducted whenever a new unit or processor is installed, a unit or processor is dissembled and reassembled at the same or new location, or major components of a mammography unit or processor equipment are changed or repaired. These evaluations shall be performed by a mammography approved qualified inspector.
6.10.2.8 Quality Control Tests-Other Modalities.
For systems with image receptor modalities other than screen-film, the quality assurance program shall be substantially the same as the quality assurance program recommended by the image receptor manufacturer, except that the maximum allowable dose shall not exceed the maximum allowable dose for screen-film systems as specified in RH 6.10.2.6.6.
6.10.2.9 Mobile Units.
Mobile mammography systems shall meet the requirements of RH 6.10.2.5 through 6.10.2.8. In addition, at each examination location, the registrant shall verify satisfactory performance of such units using a test method that establishes the adequacy of the image quality produced by the unit, prior to its use on patients.
6.10.2.10 Facility Cleanliness.
The registrant shall establish and implement adequate protocols for maintaining darkroom, screen, and view box cleanliness. The registrant shall document that all cleaning procedures are performed at the frequencies specified in the protocols.
6.10.2.11 Infection Control.
The registrant shall establish and comply with a system specifying procedures to be followed by the facility for cleaning and disinfecting mammography systems after contact with blood or other potentially infectious materials.
6.10.2.12 Quality Assurance-Mammography Medical Outcomes Audit.
Each registrant shall establish and maintain a mammography medical outcomes audit program to follow up positive mammographic assessments and to correlate pathology results with the interpreting physician's findings. The facility's first audit analysis shall be initiated no later than twelve (12) months after the date the facility becomes certified, or twelve (12) months after the effective date of these Regulations whichever date is latest. This audit analysis shall be completed within an additional twelve (12) months to permit completion of diagnostic procedures and data collection. Subsequent audit analyses will be conducted at least once every twelve (12) months.
6.10.2.13 All mammography facilities which have a current MQSA certificate or provisional certificate and a certification evaluation (not exceeding twelve (12) months old) performed by a qualified inspector authorized in mammography are considered to have met the requirements of RH 6.10, only if any deficiencies or violations cited have been corrected within thirty (30) days. RH 6.11 Severability.
The provisions of these Regulations are severable, and if any provisions or the application of the provisions to any circumstances is held invalid, the application of such provision to other circumstances, and the remainder of these Regulations shall not be affected thereby. PART 6 APPENDIX A. INFORMATION ON RADIATION SHIELDING REQUIRED FOR PLAN REVIEWS In order to provide an evaluation, technical advice, and official approval on shielding requirements for a radiation installation, the following information shall be submitted to the qualified expert.
1. The plans shall show, as a minimum, the following:
2. Information on the anticipated workload of the x-ray system(s). PART 6 APPENDIX B. DESIGN REQUIREMENTS FOR AN OPERATOR'S BOOTH DESIGN REQUIREMENTS FOR AN OPERATOR'S BOOTH 5 5 Exceptions from the above design requirements may be granted by the Department. To apply for such an exception, the facility registrant must submit a facility design review from a Qualified Expert to the Department. The review must specify the reason for the exception and it must demonstrate that the operator will have equivalent protection from radiation by use of the proposed shielding design.
1. Space Requirements:
2. Structural Requirements:
3. Viewing System Requirements:
1. Name and address of the applicant and, when applicable, the names and addresses of all locations within this State, where the service will be provided.
2. Diseases or conditions for which the x-ray examinations are to be used in diagnoses.
3. A detailed description of the x-ray examinations proposed in the screening program.
4. Description of the population to be examined in the screening program, i.e., age, sex, physical condition, and other appropriate information.
5. An evaluation of any known alternate methods not involving ionizing radiation which could achieve the goals of the screening program and why these methods are not used instead of the x-ray examinations.
6. An evaluation by a qualified expert of the x-ray system(s) to be used in the screening program prior to being placed into operation. The evaluation by the qualified expert shall show that such system(s) do satisfy all requirements of these Regulations.
7. A description of the diagnostic film quality control program, if applicable.
8. A copy of the technique chart for the x-ray examination procedures to be used.
9. The qualifications of each individual who will be operating the x-ray system(s). In the case of non- licensed operators of bone densitometry unit(s), include a copy of the waiver granted by the Board of Medical Examiners to the non-licensed operators from taking the limited scope examination.
10. The qualifications of the individual who will be supervising the operators of the x-ray system(s). The extent of supervision and the method of work performance evaluation shall be specified.
11. The name and address of the individual who will interpret the radiograph(s) or other results from the x-ray examinations.
12. Name and current license from Board of Medical Examiners of Physician(s) who will oversee the program.
13. A copy of the order prescribed by a Colorado licensed practitioner for the healing art screening program to be conducted.
14. 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.
15. A description of the procedures for the retention or disposition of the radiographs, if applicable, and other records pertaining to the x-ray examinations.