Illinois Administrative Code › Title 32 - ENERGY › Part 360 - USE OF X-RAYS IN THE HEALING ARTS INCLUDING MEDICAL, DENTAL, PODIATRY, AND VETERINARY MEDICINE › Section 360.20 - Definitions

Current through Register Vol. 48, No. 28, July 12, 2024
As used in this Part, the following definitions apply:
"Accelerator" (also "particle accelerator") means any
				therapeutic machine capable of producing a useful beam of x-rays or charged
				particles with energies of 1 MeV or greater. Accelerators include cyclotrons,
				betatrons and linear accelerators.
"Accelerator facility" means the location at which one or more
				particle accelerators are installed and are operated under the same
				administrative control.
"Agency" means the Illinois Emergency Management Agency.
"Aluminum equivalent" means the thickness of type 1100 aluminum
				alloy affording the same 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.
"Applicator" means a structure which determines the extent of
				the treatment field at a given distance from the source of the beam.
"Attenuation block" means a block or stack, having dimensions
				20 centimeters by 20 centimeters by 3.8 centimeters, of aluminum equivalent.
				Copper may be substituted for aluminum if an appropriate thickness is used for
				the kVp selected, as indicated below:
kVp
Millimeters of Copper Equivalent to 3.8 centimeters of
						  aluminum
99 or less
2.0
100 to 125
2.5
greater than 125
3.0
"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 (see
				"Phototimer").
"Barrier" (see "Protective barrier").
"Beam" means a flow of electromagnetic or particulate radiation
				that passes through the opening in the beam limiting device and that is used
				for diagnosis or treatment.
"Beam axis" (see "Central axis of the beam").
"Beam-limiting device" means a device that provides a means to
				restrict the dimensions of the x-ray field (see "Collimator", "Diaphragm" and
				"Shutter").
"Beam monitoring system" means a system of devices that will
				monitor the useful beam during irradiation and will terminate irradiation when
				a preselected number of monitor units has been accumulated.
"Beam scattering filter" means a filter placed in an electron
				beam in order to scatter the beam and provide a more uniform distribution of
				electrons in the beam.
"Central axis of the beam" means the line passing through the
				source of the beam and the center of the plane formed by the edge of the first
				beam-limiting device.
"Charged particle beam" (see "Beam").
"Coefficient of variation" means the ratio of the standard
				deviation to the mean value of a population of observations.
"Collimator" means a device or mechanism by which the x-ray
				beam is restricted in size (see "Beam-limiting device").
"Computed tomography" or "CT" means the production of a
				tomogram by the acquisition and computer processing of x-ray transmission
				data.
"Computed tomography dose index" or "CTDI" means the integral
				of the dose profile along a line perpendicular to the tomographic plane divided
				by the product of the nominal tomographic section thickness and the number of
				tomograms produced in a single scan.
"Contact hour" means the number of hours an individual is in
				contact with an instructor. One contact hour equals 50 minutes.
"Contact therapy system" means an x-ray system used for therapy
				that is designed for very short treatment distances (5 centimeters or less),
				usually employing peak tube potentials in the range of 20 to 50 kVp.
"Control panel" means that part or parts of the x-ray system
				upon which are mounted the switches, knobs, pushbuttons and other hardware
				necessary for setting the technique factors prior to initiating an x-ray
				exposure.
"CT gantry" means the tube housing assemblies, beam-limiting
				devices, detectors and the supporting structures and frames that hold 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 imaging specialist" means a person who possesses
				the knowledge, training and experience to apply the principles of radiological
				physics to diagnostic x-ray applications. The diagnostic imaging specialist
				shall be approved and registered by the Agency pursuant to 32 Ill. Adm. Code
				410.
"Diagnostic source assembly" means an x-ray tube housing
				assembly, designed for use in diagnostic x-ray applications, with a
				beam-limiting device attached.
"Diaphragm" means a device or mechanism by which the x-ray beam
				is restricted in size (see "Beam-limiting device").
"Direct supervision" means an individual is in the physical
				presence of a licensed practitioner who assists, evaluates and approves of the
				individual's performance of the various tasks involved in the application of
				ionizing radiation.
"Electronic brachytherapy" means a method of radiation therapy
				in which an electrically generated source of ionizing radiation is placed in or
				near the tumor or target tissue to deliver a therapeutic radiation
				dosage.
"Electronic brachytherapy device" means the system used to
				produce and deliver therapeutic radiation, including x-ray tube, the control
				mechanism, the cooling system and the power source.
"Electronic brachytherapy device operator" means a radiation
				therapist accredited in accordance with 32 Ill. Adm. Code 401 or a
				physician.
"Electronic brachytherapy source" means the x-ray tube
				component used in an electronic brachytherapy device.
"Field flattening filter" means a filter used to provide dose
				uniformity over the area of a useful beam of x-rays at a specified
				depth.
"Filter" means material placed in the useful beam to absorb,
				preferentially, radiations based on energy level or to modify the spatial
				distribution of the beam.
"Gantry" means that part of the system supporting and allowing
				possible movements of the radiation head.
"General purpose x-ray system" means any radiographic x-ray
				system that, by design, is not limited to radiographic examination of specific
				anatomical regions.
"Gonad shield" means a protective device for the testes or
				ovaries that provides a minimum of 0.5 millimeter lead equivalent
				protection.
"Half-value layer" or "HVL" means the thickness of a specified
				material that attenuates the beam of radiation to an extent such that the
				exposure rate is reduced to one-half of its original value.
AGENCY NOTE: The contribution of all scattered radiation, other
				than any that might be present initially in the beam concerned, should be
				minimized.
"Healing arts screening" means the examination of human beings
				using x-ray machines for the detection or evaluation of potential diseases when
				the examinations are not specifically ordered by a licensed practitioner of the
				healing arts legally authorized to prescribe such x-ray examinations for the
				purpose of diagnosis or treatment. However, healing arts screening does not
				include mammography on self-referred patients.
"Image intensifier" means a device, installed in a housing,
				that converts an x-ray pattern into a corresponding light image, usually by
				electronic means.
"Image receptor" means any device, such as a fluorescent screen
				or radiographic film, that transforms incident x-ray photons either into a
				visible image or into another form that can be made into a visible image by
				further transformations.
"Institutional review board" means a committee that has been
				formally designated by the registrant to approve, monitor and review biomedical
				and behavioral research involving humans.
"Interlock" means a device arranged or connected such that the
				occurrence of an event or condition is required before a second event or
				condition can occur or continue to occur.
"Isocenter" means a fixed point in space located at the center
				of the smallest sphere through which the central axis of the useful beam passes
				at any beam orientation.
"Kilovolts peak" or "kVp" means the crest value, in kilovolts,
				of the electric potential applied to the x-ray tube between the cathode and
				anode of a pulsating electric potential generator.
"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
				diagnostic source assembly except for:
The useful beam; and
The radiation produced when the exposure switch or timer is not
				activated.
"Leakage technique factors" means the technique factors used to
				measure leakage radiation from the diagnostic source assembly. They are defined
				as follows:
For capacitor energy storage equipment, the maximum-rated peak
				tube potential and the maximum-rated number of exposures in 1 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.
For field emission equipment rated for pulsed operation, the
				maximum-rated peak tube potential and the maximum-rated number of x-ray pulses
				in 1 hour for operation at the maximum-rated peak tube potential.
For all other equipment, the maximum-rated peak tube potential
				and the maximum-rated continuous tube current for the maximum-rated peak tube
				potential.
"Light field" means that area of the intersection of the light
				beam from the beam-limiting device and any one of the sets of planes parallel
				to and including the plane of the image receptor. The edge of the light field
				is defined as the locus of points at which the illumination is 25 percent of
				that at the center of the light field.
"Medical event" means an event that meets the criteria in
				Section
				360.120(i)(3).
"Medical radiographer" means a person other than a licensed
				practitioner, accredited in accordance with the provisions of 32 Ill. Adm. Code
				401, or an individual exempt from the provisions of 32 Ill. Adm. Code 401, who
				performs medical radiation procedures and applies x-radiation, to any part of
				the human body, for diagnostic purposes while under the supervision of a
				licensed practitioner.
"Mobile equipment" (see "X-ray equipment").
"Monitor unit" means a unit response from the beam monitoring
				system from which the absorbed dose can be calculated.
"Moving beam therapy" means radiation therapy in which there is
				displacement of the useful beam relative to the patient. Moving beam therapy
				includes arc therapy, skip therapy and rotational beam therapy.
"Operator" means an individual who applies ionizing radiation
				for diagnostic or therapeutic purposes.
"Phototimer" means a method for controlling radiation exposures
				to image receptors by the amount of radiation that reaches a radiation
				monitoring devices. The radiation monitoring devices is part of an electronic
				circuit that controls the duration of time the tube is activated (see
				"Automatic exposure control").
"Portable equipment" (see "X-ray equipment").
"Portable x-ray service provider" means a registrant who, under
				a physician's authorization, provides x-ray procedures with hand-held or mobile
				radiographic equipment in a patient's place of residence.
"Position indicating device" means a device on intraoral dental
				x-ray equipment used to indicate the beam position and to establish a definite
				source-skin distance.
"Prescribed dose" means the total dose and dose per fraction as
				documented in the written directive. The prescribed dose is an estimation from
				measured data from a specified therapeutic machine using assumptions that are
				clinically acceptable for that treatment technique and historically consistent
				with the clinical calculations previously used for patients treated with the
				same clinical technique.
"Primary protective barrier" (see "Protective barrier").
"Protective apron" means an apron of radiation absorbing
				materials, at least 0.25 millimeter lead equivalent, used to reduce exposure
				from leakage and scatter radiation.
"Protective barrier" means a barrier of radiation absorbing
				materials used to reduce radiation dose. The types of protective barriers are
				as follows:
"Primary protective barrier" means the material, excluding
				filters, placed in the useful beam to reduce the radiation dose.
"Secondary protective barrier" means a barrier sufficient to
				attenuate the leakage and scatter radiation to the required degree.
"Protective glove" means a glove made of radiation absorbing
				materials, at least 0.25 millimeter lead equivalent, used to reduce dose from
				leakage and scatter radiation.
"Radiation beam" (see "Beam").
"Radiation therapy simulation system" means a radiographic/
				fluoroscopic x-ray system used exclusively for localizing the volume to be
				exposed during radiation therapy and confirming the position and size of the
				therapeutic irradiation field.
"Radiologist assistant" means a person, other than a licensed
				practitioner, who, as a medical radiographer with advanced-level training and
				certification, performs a variety of activities under the supervision of a
				radiologist certified by the American Board of Radiology or the American
				Osteopathic Board of Radiology, in the areas of patient care, patient
				management, clinical imaging and interventional procedures. The radiologist
				assistant may not interpret images, make diagnoses or prescribe medications or
				therapies.
"Reference plane" means a plane that 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 support device with respect to the CT x-ray system between
				successive scans measured along the direction of such displacement.
"Scatter radiation" means radiation that, during passage
				through matter, has been deviated in direction.
"Secondary protective barrier" (see "Protective
				barrier").
"Shadow tray" means a device attached to the radiation head to
				support auxiliary beam-limiting material.
"Shutter" means an adjustable beam-limiting or attenuating
				device, usually made of lead, fixed to an x-ray tube housing to intercept or
				collimate the useful beam (see "Beam-limiting device").
"SID" means source-image receptor distance (see "Source-image
				receptor distance").
"Source" means the focal spot of the x-ray tube.
"Source-image receptor distance" means the distance from the
				source to the center of the input surface of the image receptor.
"Source to skin distance" or "SSD" means the distance measured
				along the central ray from the center of the front surface of the x-ray focal
				spot to the surface of the irradiated object.
"Special purpose x-ray system" means any radiographic x-ray
				system that, by design, is limited to radiographic examination of a specific
				anatomical region or to the extremities collectively.
"Spot film" means a radiograph that is made during a
				fluoroscopic examination to permanently record conditions that exist during
				that fluoroscopic procedure.
"Stationary beam therapy" means radiation therapy in which
				there is no displacement of the useful beam relative to the patient during
				irradiation.
"Stationary equipment" (see "X-ray equipment").
"Supervision" means responsibility for and control of quality,
				radiation safety and protection, and technical aspects of the application of
				ionizing radiation to human beings for diagnostic and/or therapeutic
				purposes.
"Technique factors" means the electrical potential (kilovolts),
				current (milliamperes), exposure time parameters (seconds or pulses) or a
				combination thereof, selectable at the control panel of an x-ray system (see
				"Control panel").
"Therapeutic radiological physicist" means an individual who
				has the knowledge, training and experience to measure ionizing radiation,
				evaluate safety techniques, advise regarding radiation protection needs and
				apply the principles of radiological physics to clinical radiation therapy. The
				therapeutic radiological physicist shall be approved and registered by the
				Agency pursuant to 32 Ill. Adm. Code 410.
"Tomogram" means the depiction of the x-ray attenuation
				properties of a section through the body.
"Tomographic plane" means that geometric plane that 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.
"Useful beam" (see "Beam").
"X-ray equipment" means an x-ray system, sub-system or
				component thereof. Types of x-ray equipment are as follows:
"Mobile x-ray equipment" means x-ray equipment mounted on a
				permanent base with wheels and/or casters for moving while completely
				assembled. Mobile x-ray equipment includes x-ray equipment permanently mounted
				in vehicles.
"Portable x-ray equipment" means x-ray equipment designed to be
				hand-carried.
"Stationary x-ray equipment" means x-ray equipment that is
				installed in a fixed location.
"X-ray field" means, for diagnostic purposes, 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. The edge of the x-ray field is
				defined as the locus of points at which the exposure is 25 percent of that at
				the center of the x-ray field.
"X-ray system" means an assemblage of components for the
				controlled production of x-rays. It includes minimally an x-ray high-voltage
				generator, an x-ray control panel, an x-ray 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 systems include diagnostic systems, therapeutic systems and
				accelerator systems.