Arizona Administrative Code
Title 9 - HEALTH SERVICES
Chapter 7 - DEPARTMENT OF HEALTH SERVICES - RADIATION CONTROL
Article 6 - USE OF X-RAYS IN THE HEALING ARTS
Section R9-7-602 - Definitions
The following definitions apply in this Article, unless the context otherwise requires:
"Accessible surface" means the external surface of the enclosure or housing provided by the manufacturer.
"Added filter" means the filter added to the inherent filtration.
"Aluminum equivalent" means the thickness of aluminum (type 1100 alloy) that affords equivalent attenuation, under specified conditions, as the material in question. (The nominal chemical composition of type 1100 aluminum alloy is 99.00 percent minimum aluminum, 0.12 percent copper).
"Annual" means annually within two months of the anniversary due date as determined by the original installation date, inspection date, survey date, or a reset date created by conducting a full survey before the anniversary date has arrived.
"Assembler" means any person engaged in the business of assembling, replacing, or installing one or more components into an x-ray system or subsystem.
"Attenuation block" means a block or stack, having dimensions 20 cm by 20 cm by 3.8 cm (7.9 inches by 7.9 inches by 1.5 inches) of type 1100 aluminum alloy or other materials that afford equivalent attenuation.
"Automatic exposure control" means a device that automatically controls one or more technique factors in order to obtain, at a preselected location or locations, a required quantity of radiation.
"Barrier" (See "Protective barrier")
"Beam axis" means a line from the source through the center of the x-ray field.
"Beam-limiting device" means a device that provides a means to restrict the dimensions of the x-ray field.
"C-arm x-ray system" means an x-ray system that has the image receptor and x-ray tube housing assembly connected by a common mechanical support system 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.
"Changeable filter" means any filter, exclusive of inherent filtration, which can be removed from the useful beam by an electronic, mechanical, or physical process.
"Cinefluorography" means fluorography that uses a movie camera to record fluorograph images on film for later playback.
"Coefficient of variation" means the ratio of the standard deviation to the mean value of a population of observations.
"Collimator" means an adjustable device, generally made of lead, that is fixed to an x-ray tube housing to intercept or collimate the useful beam and, if not made of lead, has a lead equivalency of not less than that of the tube housing assembly.
"Compression device" means a device used to bring object structures closer to the image plane of a radiograph and make a part of the human body a more uniform thickness so the optical density of the radiograph will be more uniform.
"Computed tomography" means the production of a tomogram by the acquisition and computer processing of x-ray transmission data. For purposes of these rules this term has the same meaning as "CT."
"Contact therapy system" means that the x-ray tube port is put in contact with or within 5 centimeters (2 inches) of the surface being treated.
"Control panel" means that part of the x-ray machine where switches, knobs, push-buttons, or other hardware necessary for manually setting the technique factors are located.
"Cooling curve" means the graphical relationship between heat units stored and cooling time.
"CT gantry" means the tube housing assemblies, beam-limiting devices, detectors, and the supporting structure, frame, and cover which hold or enclose these components.
"Dead-man switch" means a switch constructed so that a circuit-closing contact can be maintained only by continuous pressure on the switch by the operator.
"Diagnostic source assembly" means the tube housing assembly with a beam-limiting device attached.
"Diagnostic x-ray system" means an x-ray system designed for irradiation of any part of a human or animal body for the purpose of diagnosis or visualization.
"Direct scattered radiation" means scattered radiation that has been deviated in direction only by materials irradiated by the useful beam (see "Scattered radiation").
"Electronic brachytherapy" means a method of radiation therapy where an electrically generated source of ionizing radiation is placed in or near the tumor or target tissue to deliver therapeutic radiation dosage.
"Entrance exposure rate" means the roentgens per unit time at the point where the center of the useful beam enters the patient.
"Equipment" (See "X-ray equipment")
"Filter" means material placed in the useful beam to absorb undesirable radiation.
"Fluoroscopic imaging assembly" means a subsystem in which x-ray photons produce a fluoroscopic image. It includes the image receptor or receptors such as the image intensifier and spot-film device, electrical interlocks, if any, and structural material that provides a linkage between the image receptor and diagnostic source assembly.
"Fluoroscopic system" means a radiographic x-ray system used to directly visualize internal structure, the motion of internal structures, and fluids in real time, or near real-time, to aid in the treatment or diagnosis of disease, or the performance of other medical procedures.
"Focal spot" means the region of the anode target in an x-ray tube where electrons from the cathode interact to produce x-rays.
"General purpose radiographic x-ray system" means any radiographic x-ray system that, by design, is not limited to radiographic examination of a specific anatomical region.
"Gonadal shield" means a protective barrier for the testes or ovaries.
"Grid" means a device used to improve the image detail in a radiograph by reducing the intensity of x-ray scatter radiation exiting the film side of the patient.
"Half-value layer" or "HVL" means the thickness of a specified material that attenuates the beam of radiation to an exposure rate that is one-half of its original value. In this definition, the contribution of any scattered radiation, other than that which is present initially in the beam, is excluded.
"Healing arts radiography" means the application of x-radiation to human patients for diagnostic or therapeutic purposes by a licensed practitioner or a person certified in accordance with R9-7-603(B)(1), at the direction of a licensed practitioner. Healing arts radiography includes:
Positioning the x-ray beam with respect to the patient,
Anatomicalpositioning of the patient,
Selecting exposure factors, or
Initiating the exposure.
"Healing arts screening" means the application of radiation from an x-ray machine to a human for the detection or evaluation of health indications when the tests are not specifically and individually ordered by a licensed practitioner.
"Image intensifier" means an electronic device, installed in an x-ray system housing, which instantaneously converts an x-ray pattern into a corresponding light image of higher intensity.
"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 transformation.
"Inherent filtration" means the filtration of the useful beam by permanently installed components of the tube housing assembly.
"Kilovolts peak" or "kVp" (See "Peak tube potential")
"Lateral fluoroscope" means the x-ray tube and image receptor combination in a biplane system dedicated to the lateral projection. It consists of the lateral x-ray tube housing assembly and the lateral image receptor that are fixed in position relative to the table with the x-ray beam axis parallel to the plane of the table.
"Lead equivalent" means the thickness of lead affording the same attenuation, under specified conditions, as the material in question.
"Leakage radiation" means all radiation emanating from the tube housing except the useful beam and radiation produced when the exposure switch or timer is not activated.
"Leakage technique factors" means the technique factors associated with the diagnostic source assembly that are used in measuring leakage radiation. Included are:
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 (mAs) or the minimum obtainable from the unit, whichever is larger,
For field emission equipment rated for pulsed operation, the maximum-rated peak tube potential and maximum-rated number of x-ray pulses in an hour for operation at the maximum-rated peak tube potential; and
For all other source assemblies, the maximum-rated peak tube potential and maximum-rated continuous tube current for the maximum-rated peak tube potential.
"mA" means milliampere.
"Mammographic x-ray system" means an x-ray system that is specifically engineered to image human breasts.
"mAs" means milliampere second.
"Mobile equipment" (See "X-ray equipment")
"Peak tube potential" means the maximum value of the potential difference across the x-ray tube during an exposure.
"Phantom" means a volume of material that behaves in a manner similar to tissue with respect to the attenuation and scattering of radiation. (i.e. "Breast phantom" means an artificial test object that simulates the average composition of, and various structures in the breast.)
"Phototimer" (See "Automatic exposure control")
"Portable equipment" (See "X-ray equipment")
"Primary protective barrier" (See "Protective barrier")
"Protective apron" means an apron made of radiation, absorbing material used to reduce radiation exposure.
"Protective barrier" means a barrier of radiation-absorbing material used to reduce radiation exposure.
"Primary protective barrier" means the material, excluding filters, placed in the useful beam.
"Secondary protective barrier" means the material which attenuates stray radiation.
"Protective glove" means a glove made of radiation-absorbing material used to reduce radiation exposure.
"Radiologic physicist" means an individual who:
Is certified by the American Board of Radiology, American Board of Medical Physics, or the American Board of Health Physics;
Possesses documentation of state approval;
Holds a master's degree or higher in a physical science; and
Meets the training and certification requirements in R9-7-615(A)(1)(c).
"Scattered radiation" means radiation that, during passage through matter, has been deviated in direction. (See "Direct scattered radiation")
"Screen" or "intensifying screen" means a device that converts the energy of the x-ray beam into visible light that interacts with the radiographic film, forming a latent image, or contains photostimulable phosphor plates that upon exposure, emit visible or nonvisible light to create an image.
"Secondary protective barrier" (See "Protective barrier")
"Shutter" (See "Collimator")
"Source" means the focal spot of the x-ray tube.
"Source-to-image receptor distance" or "SID" means the distance from the source to the center of the input surface of the image receptor.
"Spot check" means an abbreviated calibration procedure which is performed to assure that a previous calibration continues to be valid. Also, a spot film may be taken to improve visualization by arresting motion and to document medical observations. Note that in some cases, a film may not be created.
"Stationary equipment" (See "X-ray equipment")
"Stray radiation" means the sum of leakage and scattered radiation.
"System" (See "X-ray system")
"Technique chart" means a tabulation of technique factors.
"Technique factors" means the following conditions of operation:
For capacitor energy storage equipment, peak tube potential in kV and quantity of charge in mAs;
Forfield emission equipment rated for pulsed operation, peak tube potential in kV, and number of x-ray pulses;
ForCT 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 number of x-ray pulses per scan, or the product of tube current, x-ray pulse width, and number of x-ray pulses in mAs;
ForCT 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, exposure time in mAs, when the scan time and exposure time are equivalent; and
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.
"Treatment simulator" means a diagnostic x-ray system that duplicates a medical particle accelerator or other tele-therapy in terms of its geometrical, mechanical, and optical qualities; the main function of which, is to display radiation treatment fields so that the target volume may be accurately included in the area of irradiation without delivering excess radiation to surrounding normal tissue.
"Tube" means x-ray tube unless otherwise specified.
"Tube housing assembly" means the tube housing with the tube installed. It includes high-voltage or filament transformers and other elements contained within the tube housing.
"Tube rating chart" means the set of curves that specify the rated limits of operation of the tube in terms of the technique factors.
"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 that causes the system to produce radiation.
"Visible area" means that portion of the input surface on the image receptor over which incident x-ray photons are producing a visible image.
"X-ray equipment" means an x-ray system, subsystem, or component described further by the following terms:
"Hand-held" means x-ray equipment designed to be held by an operator while being used.
"Mobile" means x-ray equipment mounted on a permanent base with wheels or casters for moving while completely assembled.
"Portable" means x-ray equipment designed to be hand-carried, but used with a cord or delayed timer system that allows the operator to be six feet or more away from the useful beam.
"Stationary" means x-ray equipment installed in a fixed location.
"Transportable mobile" means x-ray equipment installed in a vehicle or trailer.
"X-ray system" means an assemblage of components for the controlled production of x-rays. It includes, at minimum, an x-ray high-voltage generator, an x-ray control, a tube housing assembly, a beam-limiting device, and the necessary supporting structures. Additional components that function with the system are considered integral parts of the system.
"X-ray tube" means any electron tube that is designed for the conversion of electrical energy into x-ray energy. For purposes of the rules contained in 9 A.A.C. 7, this term is synonymous with "tube."
