HAR §11-45-2. Definitions

As used in this chapter: "Absorbed dose" means the energy imparted by ionizing radiation per unit mass of irradiated material. The units of absorbed dose are the gray (Gy) and the rad. "Accelerator-produced material" means any material made radioactive by a particle accelerator. "Accessible surface" means the external surface of the enclosure or housing of an x-ray system component provided by the manufacturer. "Activity" means the rate of disintegration or transformation or decay of radioactive material. The units of activity are the becquerel (Bq) and the curie (Ci). "Added filtration" means any filtration which is in addition to the inherent filtration. "Address of use" means the building or buildings that are identified on the license and where radioactive material may be §11-45-2 45-8 produced, prepared, received, used, or stored. "Adult" means an individual eighteen or more years of age. "Air kerma" (K) means the kinetic energy released in air by ionizing radiation. Kerma is determined as the quotient of dE by dM, where dE is the sum of the initial kinetic energies of all the charged ionizing particles liberated by uncharged ionizing particles in air of mass dM. The SI unit of air kerma is joule per kilogram and the special name for the unit of kerma is the gray (Gy). "Airborne radioactive material" means any radioactive material dispersed in the air in the form of dusts, fumes, particulates, mists, vapors, or gases. "Airborne radioactivity area" means a room, enclosure, or area in which airborne radioactive materials exist in concentrations: (1) In excess of the derived air concentrations (DACs) specified in Appendix B, Table I, of subchapter 4, or (2) To such a degree that an individual present in the area without respiratory protective equipment could exceed, during the hours an individual is present in a week, an intake of 0.6 percent of the annual limit on intake (ALI) or twelve DAC-hours. "Aluminum equivalent" means the thickness of type 1100 aluminum alloy affording the same attenuation, under specified conditions, as the material in question. "Analytical x-ray equipment" means equipment used for x-ray diffraction or fluorescence analysis. "Analytical x-ray system" means a group of components utilizing x or gamma rays to determine the elemental composition or to examine the microstructure of materials. "Annual limit on intake" (ALI) means the derived limit for the amount of radioactive material taken into the body of an adult worker by inhalation or ingestion in a year. ALI is the smaller value of intake of a given radionuclide in a year by the reference man that would result in a committed effective dose equivalent of five rems (0.05 sievert) or a committed dose equivalent of fifty rems (0.5 sievert) to any individual organ or tissue. ALI values for intake by ingestion and by inhalation of selected radionuclides are given in Table I, Columns 1 and 2, of Appendix B of subchapter 4. "Applicator" means a structure which determines the extent of the treatment field at a given distance from the virtual source. "Area of use" means a portion of a physical structure that has been set aside for the purpose of producing, preparing, receiving, using, or storing radioactive material. "As low as is reasonably achievable" (ALARA) means making every reasonable effort to maintain exposures to radiation as far below the dose limits in these rules as is practical, consistent with the purpose for which the licensed activity is undertaken, taking into account the state of technology, the economics of improvements in relation to state of technology, the economics of improvements in relation to benefits to the public health and safety, and other societal and socioeconomic considerations, and §11-45-2 45-9 in relation to utilization of nuclear energy and licensed sources of radiation in the public interest. "Assembler" means any person engaged in the business of assembling, replacing, or installing one or more components into an x-ray system or subsystem. The term includes the owner of an x-ray system or his or her employee or agent who assembles components into an x-ray system that is subsequently used to provide professional or commercial services. "Attenuation block" means a block or stack of type 1100 aluminum alloy or aluminum alloy having equivalent attenuation with dimensions twenty centimeters by twenty centimeters by 3.8 centimeters, of type 1100 aluminum alloy or other materials having equivalent attenuation. "Automatic exposure control" means a device which automatically controls one or more technique factors in order to obtain at a preselected location(s) a required quantity of radiation. (Includes devices such as phototimers and ion chambers.) "Background radiation" means radiation from cosmic sources; naturally-occurring radioactive materials, including radon, except as a decay product of source or special nuclear material, and including global fallout as it exists in the environment from the testing of nuclear explosive devices. "Background radiation" does not include sources of radiation from radioactive materials regulated by the department. "Beam axis" means a line from the source through the centers of the x-ray fields. "Beam-limiting device" means a device which provides a means to restrict the dimensions of the x-ray field. "Beam scattering filter" means a filter used in order to scatter a beam of electrons. "Becquerel" (Bq) means the SI unit of activity. One becquerel is equal to one disintegration or transformation per second (s-1). "Bioassay" means the determination of kinds, quantities or concentrations, and, in some cases, the locations of radioactive material in the human body, whether by direct measurement, in vivo counting, or by analysis and evaluation of materials excreted or removed from the human body. For purposes of these rules, "radiobioassay" is an equivalent term. "Byproduct material" means: (1) Any radioactive material, except special nuclear material, yielded in or made radioactive by exposure to the radiation incident to the process of producing or utilizing special nuclear material; and (2) The tailings or wastes produced by the extraction or concentration of uranium or thorium from ore processed primarily for its source material content, including discrete surface wastes resulting from uranium or thorium solution extraction processes. Underground ore bodies depleted by these solution extraction operations do not constitute "byproduct material" within this definition. "C-Arm x-ray system" means an x-ray system in which the §11-45-2 45-10 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. "Cabinet radiography" means industrial radiography conducted in an enclosure or cabinet shielded so that radiation levels at every location on the exterior meet the limitations specified in subchapter 4 of these rules. "Cabinet x-ray system" means an x-ray system with the x-ray tube installed in an enclosure independent of existing archi- tectural structures except the floor on which it may be placed. The cabinet x-ray system is intended to contain at least that portion of a material being irradiated, provide radiation attenuation, and exclude personnel from its interior during generation of radiation. Included are all x-ray systems designed primarily for the inspection of carry-on baggage at airline, railroad, and bus terminals, and in similar facilities. An x-ray tube used within a shielded part of a building, or x-ray equipment which may temporarily or occasionally incorporate portable shielding, is not considered a cabinet x-ray system. "Calendar quarter" means not less than twelve consecutive weeks nor more than fourteen consecutive weeks. The first calendar quarter of each year shall begin in January and subsequent calendar quarters shall be so arranged such that no day is included in more than one calendar quarter and no day in any one year is omitted from inclusion within a calendar quarter. No licensee shall change the method observed by him of determining calendar quarters for purposes of this chapter except at the beginning of a calendar year. "Calibration" means the determination of: (1) The response or reading of an instrument relative to a series of known radiation values over the range of the instrument; or (2) The strength of a source of radiation relative to a standard. "Carrier" means a person engaged in the transportation of passengers or property by land or water as a common, contract, or private carrier, or by civil aircraft. "Central axis of the beam" means a line passing through the virtual source and the center of the plane figure formed by the edge of the first beam limiting device. "Cephalometric device" means a device intended for the radiographic visualization and measurement of the dimensions of the human head. "Certified cabinet x-ray system" means an x-ray system which has been certified in accordance with 21 C.F.R. ? 1010.2 as being manufactured and assembled pursuant to the provisions of 21 C.F.R. ? 1020.40. "Certified components" means components of x-ray systems which are subject to regulations promulgated under Public Law 90- 602, Radiation Control for Health and Safety Act of 1968. "Certified system" means any x-ray system which has one or more certified component(s). §11-45-2 45-11 "C.F.R." means Code of Federal Regulations. "Changeable filters" means any filter, exclusive of inherent filtration, which can be removed from the useful beam through any electronic, mechanical, or physical process. "Chelating agent" means amine polycarboxylic acids, hydroxycarboxylic acids, gluconic acid, and polycarboxylic acids. "Class" means a classification scheme for inhaled material according to its rate of clearance from the pulmonary region of the lung. Materials are classified as D, W, or Y, which applies to a range of clearance half-times: for Class D, Days, of less than ten days, for Class W, Weeks, from ten to one hundred days, and for Class Y, Years, of greater than one hundred days. For purposes of these rules, "lung class" and "inhalation class" are equivalent terms. "Coefficient of variation" means the ratio of the standard deviation to the mean value of a population of observations. "Collective dose" means the sum of the individual doses received in a given period of time by a specified population from exposure to a specified source of radiation. "Collimator" means a device used to limit the size, shape, and direction of the primary radiation beam. "Committed dose equivalent" (HT,50) means the dose equivalent to organs or tissues of reference (T) that will be received from an intake of radioactive material by an individual during the fifty-year period following the intake. "Committed effective dose equivalent" (HE, 50) is the sum of the products of the weighting factors applicable to each of the body organs or tissues that are irradiated and the committed dose equivalent to each of these organs or tissues (HE,50 = Σ wT,HT,50). "Computed tomography" (CT) means the production of a tomogram by the acquisition and computer processing of x-ray transmission data. "Contrast scale" means the change in the linear attenuation coefficient per CTN relative to water, that is: µx - µw CS = (CTN)x - (CTN)w where: µx = Linear attenuation coefficient of the material of interest. µw = Linear attenuation coefficient of water. (CTN)x = CTN of the material of interest. (CTN)w = CTN of water. "Control panel" means that part of the x-ray control upon which are mounted the switches, knobs, push buttons, and other hardware necessary for setting the technique factors. "Controlled area" means an area, outside of a restricted area but inside the site boundary, access to which can be limited by the licensee for any reason. "Cooling curve" means the graphical relationship between heat units stored and cooling time. §11-45-2 45-12 "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. "CT gantry" means the tube housing assemblies, beam-limiting devices, detectors, and the supporting structures and frames which hold these components. "Curie" (Ci) means a unit of quantity of radioactivity. One curie is that quantity of radioactive material which decays at the rate of 3.7 x 1010 transformations per second (tps). "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. "Declared pregnant woman" means a woman who has voluntarily informed her employer, in writing, of her pregnancy. "Deep dose equivalent" (Hd), which applies to external whole body exposure, means the dose equivalent at a tissue depth of one centimeter (one-thousand milligrams per square centimeter). "Department" means the department of health. "Derived air concentration" (DAC) means the concentration of a given radionuclide in air which, if breathed by the reference man for a working year of two thousand hours under conditions of light work, results in an intake of one ALI. For purposes of these rules, the condition of light work is an inhalation rate of 1.2 cubic meters of air per hour for two thousand hours in a year. DAC values are given in Table I, Column 3, of Appendix B of subchapter 4. "Derived air concentration-hour" (DAC-hour) means the product of the concentration of radioactive material in air, expressed as a fraction or multiple of the derived air concentration for each radionuclide, and the time of exposure to that radionuclide, in hours. A licensee may take two thousand DAC-hours to represent one ALI, equivalent to a committed effective dose equivalent of five rems (0.05 sievert). "Detector" (See "Radiation detector"). "Diagnostic clinical procedures manual" means a collection of written procedures that describes each method (and other instructions and precautions) by which the licensee performs diagnostic clinical procedures; where each diagnostic clinical procedure has been approved by the authorized user and includes the pharmaceutical, dosage, and route of administration. "Diagnostic source assembly" means the tube housing assembly with a beam-limiting device attached. "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. "Diagnostic x-ray system" means an x-ray system designed for irradiation of any part of the human or animal body for the purpose of diagnosis or visualization. "Direct scattered radiation" means that scattered radiation which has been deviated in direction only by materials irradiated by the useful beam (See "Scattered radiation"). "Director" means the director of the department of health, §11-45-2 45-13 State of Hawaii, or a duly authorized agent. "Dose" is a generic term that means absorbed dose, dose equivalent, effective dose equivalent, committed dose equivalent, committed effective dose equivalent, or total effective dose equivalent. For purposes of these rules, "radiation dose" is an equivalent term. "Dose equivalent" (HT) means the product of the absorbed dose in tissue, quality factor, and all other necessary modifying factors at the location of interest. The units of dose equivalent are the sievert (Sv) and rem. "Dose limits" means the permissible upper bounds of radiation doses established in accordance with these rules. For purposes of these rules, "limits" is an equivalent term. "Dose monitoring system" means a system of devices for the detection, measurement, and display of quantities of radiation. "Dose monitor unit" means a unit response from the dose monitoring system from which the absorbed dose can be calculated. "Dose profile" means the dose as a function of position along a line. "Dosimetry processor" means person that processes and evaluates individual monitoring devices in order to determine the radiation dose delivered to the monitoring devices. "Effective dose equivalent" (HE) means the sum of the products of the dose equivalent to each organ or tissue (HT) and the weighting factor (wT) applicable to each of the body organs or tissues that are irradiated (HE = Σ wTHT). "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"). "Embryo/fetus" means the developing human organism from conception until the time of birth. "Entrance or access point" means any opening through which an individual or extremity of an individual could gain access to radiation areas or to licensed radioactive materials. This includes entry or exit portals of sufficient size to permit human entry, irrespective of their intended use. "Entrance exposure rate" means the exposure free in air per unit time at the point where the center of the useful beam enters the patient. "Existing equipment" means therapy systems subject to subchapter 14 which were manufactured on or before January 1, 1985. "Explosive material" means any chemical compound, mixture, or device which produces a substantial instantaneous release of gas and heat spontaneously or by contact with sparks or flame. "Exposure" means, when used as a verb, being exposed to ionizing radiation or to radioactive material. When used as a noun, "exposure" means the quotient of dQ by dm where "dQ" is the absolute value of the total charge of the ions of one sign produced in air when all the electrons (negatrons and positrons) liberated by photons in a volume element of air having mass "dm" are completely stopped in air. The special unit of exposure is the roentgen (R). One roentgen is equal to 2.58 x 10-4 coulombs per kilogram of air. §11-45-2 45-14 "Exposure rate" means the exposure per unit of time, such as roentgen per minute and milliroentgen per hour. "External dose" means that portion of the dose equivalent received from any source of radiation outside the body. "Extremity" means hand, elbow, arm below the elbow, foot, knee, and leg below the knee. "Eye dose equivalent" means the external dose equivalent to the lens of the eye at a tissue depth of 0.3 centimeter (three hundred milligrams per centimeter squared). "Facility" means the location at which one or more devices or sources are installed and/or located within a building, office, vehicle, or under one roof. "Fail-safe characteristics" mean a design feature which causes beam port shutters to close, or otherwise prevents emergence of the primary beam, upon the failure of a safety or warning device. "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. "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. "Field size" means the dimensions along the major axes of an area in a plane perpendicular to the specified direction of the beam of incident radiation at the normal treatment distance and defined by the intersection of the major axes and the fifty percent isodose line. Material shall be placed in the beam such that dose maximum is produced at the normal treatment distance when field size is being determined. "Filter" means material placed in the useful beam to absorb preferentially selected radiations. "Fissile material" means any special nuclear material consisting of or containing one or more fissile radionuclides. Fissile radionuclides are plutonium-238, plutonium-239, plutonium- 241, uranium-233, and uranium-235. Neither natural nor depleted uranium is fissile material. "Fluoroscopic imaging assembly" means a subsystem in which x-ray photons produce a fluoroscopic 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 on the anode of the x-ray tube bombarded by the electrons accelerated from the cathode and from which the useful beam originates. "Gantry" means that part of the system supporting and allowing possible movements of the radiation head. "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. "Giga-" (G) means one billion times when used in conjunction with a specified unit. "Gonad shield" means a protective barrier for the testes or ovaries. "Gray" (Gy) means the SI unit of absorbed dose. One gray is §11-45-2 45-15 equal to an absorbed dose of one joule per kilogram (one hundred rads). "Half-value layer" means the thickness of specified material which attenuates the beam of radiation to an extent such that the exposure rate is reduced to 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 concerned, is deemed to be excluded. "Hazardous waste" means those wastes designated as hazardous by U.S. Environmental Protection Agency regulations in 40 C.F.R. Part 261. "Healing arts" means the medical, dental, chiropractic, podiatric, and veterinary professions. "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 tests for the purpose of diagnosis or treatment. "High radiation area" means an area, accessible to individuals, in which radiation levels could result in an individual receiving a dose equivalent in excess of 0.1 rem (one millisievert) in one hour at thirty centimeters from any source of radiation or from any surface that the radiation penetrates. For purposes of these rules, rooms or areas in which diagnostic x-ray systems are used for healing arts purposes are not considered high radiation areas. "HRS" means Hawaii Revised Statutes. "Human use" means the internal or external administration of radiation or radioactive material to human beings. "HVL" See "Half-value layer". "Image intensifier" means a device, installed in its housing, which instantaneously converts an x-ray pattern into a corresponding light image of higher energy density. "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 during mammography. "Individual" means any human being. "Individual monitoring" means the assessment of: (1) Dose equivalent by the use of individual monitoring devices or by the use of survey data; or (2) Committed effective dose equivalent by bioassay or by determination of the time-weighted air concentrations to which an individual has been exposed, that is, DAC- hours. "Individual monitoring devices" means devices designed to be worn by a single individual for the assessment of dose equivalent. For purposes of these rules, individual monitoring equipment and personnel monitoring equipment are equivalent terms. Examples of individual monitoring devices are film badges, §11-45-2 45-16 thermoluminescent dosimeters (TLDs), pocket ionization chambers, and personal air sampling devices. "Industrial radiography" means the examination of the macroscopic structure of materials by nondestructive methods using sources of ionizing radiation to produce radiographic images. "Inherent filtration" means the filtration of the useful beam provided by the permanently installed components of the tube housing assembly. "Inspection" means an official examination or observation including but not limited to, tests, surveys, and monitoring to determine compliance with rules, orders, requirements, and conditions of the department. "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. "Internal dose" means that portion of the dose equivalent received from radioactive material taken into the body. "Interruption of irradiation" means the stopping of irradiation with the possibility of continuing irradiation without resetting of operating conditions at the control panel. "Ionizing radiation" means any radiation consisting of charged particles having sufficient kinetic energy to produce ionization by collision, or uncharged particles which can liberate directly ionizing particles or can initiate a nuclear transformation, or a mixture of both charged and uncharged particles. "Irradiation" means the exposure of matter to ionizing radiation. "Isocenter" means a fixed point in space located at the center of the smallest sphere through which the central axis of the beams passes in all conditions. "Kilo-" (k) means one thousand times when used in conjunction with a specified unit. "Kilovolts peak" (See "Peak tube potential"). "kV" means kilovolts. "kVp" (See "Peak tube potential"). "kWs" means kilowatt second. "Landfill" means a disposal facility or part of a facility at which solid waste is permanently placed in or on land and which is not a landspreading facility. "Landspreading facility" means a facility that applies sludges or other solid wastes onto or incorporates solid waste into the soil surface at greater than vegetative utilization and soil conditioner and/or immobilization rates. "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 or therapeutic source assembly except for: (1) The useful beam; and (2) Radiation produced when the exposure switch or timer is not activated. "Leakage technique factors" means the technique factors associated with the diagnostic source assembly which are used in §11-45-2 45-17 measuring leakage radiation. They are defined as follows: (l) 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 ten millicoulombs, i.e., ten 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 the maximum-rated peak tube potential. "License" means a written authorization issued by the department in accordance with the rules adopted by the department, when used without reference to the U.S. Nuclear Regulatory Commission, agreement state, or other state. "Licensee" means any person who is issued a license by the department and is legally obligated to have a license with the department pursuant to these rules. "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. "Limits" (See "Dose limits"). "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 (Vn-Vl)/Vl where Vn = No-load line potential and Vl = Load line potential. "Local components" mean part of an analytical x-ray system and include areas that are struck by x-rays such as radiation source housings, port and shutter assemblies, collimators, sample holders, cameras, goniometers, detectors, and shielding, but do not include power supplies, transformers, amplifiers, readout devices, and control panels. "Lost or missing licensed material" means licensed material whose location is unknown. This definition includes licensed material that has been shipped but has not reached its planned destination and whose location cannot be readily traced in the transportation system. "mA" means milliampere. "mAs" means milliampere second. "Major processor" means a user processing, handling, or manufacturing radioactive material exceeding Type A quantities as unsealed sources or material, or exceeding four times Type B quantities as sealed sources, but does not include nuclear medicine programs, universities, industrial radiographers, or §11-45-2 45-18 small industrial programs. Type A and B quantities are defined in 10 C.F.R. §71.4. "Maximum line current" means the root-mean-square current in the supply line of an x-ray machine operating at its maximum rating. "Mega-" (M) means a million times when used in conjunction with a specified unit. "Member of the public" means an individual in a controlled or unrestricted area. However, an individual is not a member of the public during any period in which the individual receives an occupational dose. "Micro-" (µ) means one-millionth of when used in conjunction with a specified unit. "Milli-" (m) means one-thousandth of when used in conjunction with a specified unit. "Minor" means an individual less than eighteen years of age. "Misadministration" means the administration of: (1) External beam radiation therapy involving the wrong patient, wrong treatment modality, or wrong treatment site; when the treatment consists of three or fewer fractions and the calculated total administered dose differs from the total prescribed dose by more than ten percent of the total prescribed dose; when the calculated weekly administered dose is thirty percent greater than the weekly prescribed dose; or when the calculated total administered dose differs from the total prescribed dose by more than twenty percent of the total prescribed dose; (2) A therapeutic radiopharmaceutical dosage involving the wrong patient, wrong radiopharmaceutical, or wrong route of administration, or when the administered dosage differs from the prescribed dosage by more than twenty percent of the prescribed dosage; (3) A gamma stereotactic radiosurgery radiation dose involving the wrong patient or wrong treatment site, or when the calculated total administered dose differs from the total prescribed dose by more than ten percent of the total prescribed dose; (4) A teletherapy radiation dose involving the wrong patient, wrong mode of treatment, or wrong treatment site, or when the treatment consists of three or fewer fractions and the calculated total administered dose differs from the total prescribed dose by more than ten percent of the total prescribed dose, or when the calculated weekly administered dose is thirty percent greater than the weekly prescribed dose, or when the calculated total administered dose differs from the total prescribed dose by more than twenty percent of the total prescribed dose; (5) A brachytherapy radiation dose involving the wrong patient, wrong radionuclide, or wrong treatment site (excluding, for permanent implants, seeds that were implanted in the correct site but migrated outside the treatment site), or involving a sealed source that is §11-45-2 45-19 leaking, or when, for a temporary implant, one or more sealed sources are not removed upon completion of the procedure, or when the calculated administered dose to the treatment site differs from the prescribed dose by more than twenty percent of the prescribed dose; (6) A diagnostic radiopharmaceutical dosage, both involving the wrong patient, wrong radiopharmaceutical, wrong route of administration, or when the administered dosage differs by more than twenty percent of the prescribed dosage, and when the dose to the patient exceeds five rems (fifty millisieverts) effective dose equivalent or fifty rems (five hundred millisieverts) dose equivalent to any individual organ. "Mobile nuclear medicine service" means the transportation and medical use of radioactive material. "Mobile x-ray equipment" (See "X-ray equipment"). "Monitoring" means the measurement of radiation, radioactive material concentrations, surface area activities or quantities of radioactive material and the use of the results of these measurements to evaluate potential exposures and doses. For purposes of these rules, radiation monitoring and radiation protection monitoring are equivalent terms. "Moving beam therapy" means radiation therapy with relative displacement of the useful beam and the patient during irradiation. It includes arc therapy, skip therapy, and rotational therapy. "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. "Nano-" (n) means one-billionth of when used in conjunction with a specified unit. "NARM" means any naturally-occurring and/or accelerator- produced radioactive material. It does not include byproduct, source, or special nuclear material. "Natural radioactivity" means radioactivity of naturally occurring nuclides. "New equipment" means systems subject to subchapter 14 which were manufactured after January 1, 1985. "Noise" means the standard deviation of the fluctuations in CTN expressed as a percentage of the attenuation coefficient of water. Its estimate (Sn) is calculated using the following expression: Sn = 100 x CS x s µw where: CS = Contrast scale µw = Linear attenuation coefficient of water. s = Estimated standard deviation of the CTN of picture elements in a specified area of the CT image. "Nominal tomographic section thickness" means the full width §11-45-2 45-20 at half-maximum of the sensitivity profile taken at the center of the cross-sectional volume over which x-ray transmission data are collected. "Nonstochastic effect" means a health effect, the severity of which varies with the dose and for which a threshold is believed to exist. Radiation-induced cataract formation is an example of a nonstochastic effect. For purposes of these rules, a "deterministic effect" is an equivalent term. "Normal operating procedures" mean step-by-step instructions necessary to accomplish the analysis. These procedures shall include sample insertion and manipulation, equipment alignment, routine maintenance by the licensee, and data recording procedures, which are related to radiation safety. "Normal treatment distance" means: (1) For electron irradiation, the virtual source to surface distance along the central axis of the useful beam as specified by the manufacturer for the applicator; and (2) For x-ray irradiation, the virtual source to isocenter distance along the central axis of the useful beam. For non-isocentric equipment, this distance shall be that specified by the manufacturer. "Occupational dose" means the dose received by an individual in a restricted area or in the course of employment in which the individual's assigned duties involve exposure to sources of radiation, whether in the possession of the licensee, or other person. Occupational dose does not include dose received: from background radiation, as a patient from medical practices, from voluntary participation in medical research programs, or as a member of the public. "Open-beam configuration" means an analytical x-ray system in which an individual could accidentally place some part of his body in the primary beam path during normal operation. "Package" means the packaging together with its radioactive contents as presented for transport. "Particle accelerator" means any machine capable of accelerating electrons, protons, deuterons, or other charged particles in a vacuum and of discharging the resultant particulate or other radiation into a medium at energies usually in excess of one megaelectron volt. "Patient" means an individual or animal subjected to healing arts examination, diagnosis, or treatment. "PBL" (See "Positive Beam Limitation"). "Peak tube potential" means the maximum value of the potential difference across the x-ray tube during an exposure. "Permanent radiographic installation" means an installation or structure designed or intended for radiography and in which radiography is regularly performed. "Person" means any individual, partnership, firm, association, public or private corporation, trust estate or any other legal entity. "Personal supervision" means guidance and instruction provided to a radiographer trainee by a radiographer instructor who is present at the site, in visual contact with the trainee §11-45-2 45-21 while the trainee is using sources of radiation, and in such proximity that immediate assistance can be given if required. "Personnel monitoring equipment" (See "Individual monitoring devices"). "Phantom" means a volume of material behaving in a manner similar to tissue with respect to the attenuation and scattering of radiation. This requires that both the atomic number (Z) and the density of the material be similar to that of tissue. "Picture element" means an elemental area of a tomogram. "Pico-" (p) means one-trillionth of when used in conjunction with a specified unit. "PID" (See "Position indicating device"). "Planned special exposure" means an infrequent exposure to radiation, separate from and in addition to the annual occupational dose limits. "Portable x-ray equipment" (See "X-ray equipment"). "Position indicating device" 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" means the automatic or semi- automatic adjustment of an x-ray beam to the selected image receptor size, whereby exposures cannot be made without such adjustment. "Prescribed dosage" means the quantity of radiopharmaceutical activity as documented: (1) In a written directive; or (2) Either in the diagnostic clinical procedures manual or in any appropriate record in accordance with the directions of the authorized user for diagnostic procedures. "Prescribed dose" means: (1) The total dose and dose per fraction as documented in the written directive for external beam radiotherapy which is an estimation from measured data from a specified therapeutic radiation 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; or (2) The total dose as documented in the written directive for gamma stereotactic radiosurgery; or (3) The total dose and dose per fraction as documented in the written directive for teletherapy; or (4) Either the total source strength and exposure time, or the total dose, as documented in the written directive for brachytherapy. "Primary beam" means radiation which passes through an aperture of the source housing by a direct path from the x-ray tube or a radioactive source located in the radiation source housing. "Primary protective barrier" See "Protective barrier". "Protective apron" means an apron made of radiation absorbing materials used to reduce radiation exposure. §11-45-2 45-22 "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 useful beam. (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. "Public dose" means the dose received by a member of the public from exposure to sources of radiation either within a licensee's controlled area or in unrestricted areas. It does not include occupational dose, dose received from background radiation, dose received as a patient from medical practices, or dose from voluntary participation in medical research programs. "Qualified health physicist" means a physicist licensed to provide health physics services. "Qualified medical physicist" means a physicist licensed to provide medical physics services. "Quality factor" (Q) means the modifying factor that is used to derive dose equivalent from absorbed dose. "Quarter" means a period of time equal to one-fourth of the year observed by the licensee, approximately thirteen consecutive weeks, providing that the beginning of the first quarter in a year coincides with the starting date of the year and that no day is omitted or duplicated in consecutive quarters. "Rad" means the special unit of absorbed dose. One rad is equal to an absorbed dose of one hundred erg per gram or 0.01 joule per kilogram (0.01 gray). "Radiation" means alpha particles, beta particles, gamma rays, x-rays, neutrons, high-speed electrons, high-speed protons, and other particles capable of producing ions. For purposes of these rules, ionizing radiation is an equivalent term. Radiation, as used in these rules, does not include non-ionizing radiation, such as radiowaves or microwaves, visible, infrared, or ultraviolet light. "Radiation area" means any area, accessible to individuals, in which radiation levels could result in an individual receiving a dose equivalent in excess of 0.005 rem (0.05 millisievert) in one hour at thirty centimeters from the source of radiation or from any surface that the radiation penetrates. "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 head" means the structure from which the useful beam emerges. "Radiation machine" means any device capable of producing radiation except those devices with radioactive material as the only source of radiation. "Radiation safety officer" means an individual who has the knowledge and responsibility to apply appropriate radiation protection regulations. "Radiation therapy simulation system" means a radiographic or fluoroscopic x-ray system intended for localizing the volume to §11-45-2 45-23 be exposed during radiation therapy and confirming the position and size of the therapeutic irradiation field. "Radioactive material" means any solid, liquid, or gas which emits radiation spontaneously. "Radioactivity" means the transformation of unstable atomic nuclei by the emission of radiation. "Radiobioassay" (See "Bioassay"). "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. "Radiographer" means any individual in industrial radiography who performs or personally supervises industrial radiographic operations, or any individual in the healing arts who practices radiography on human patients as specified in chapter 11-44. "Radiographer instructor" means any radiographer who has been authorized by the department to provide on-the-job training to radiographer trainees, relative to industrial radiography. "Radiographer trainee" means any individual who, under the personal supervision of a radiographer instructor, uses sources of radiation, related handling tools, or radiation survey instruments during the course of his instruction, relative to industrial radiography. "Radiographic imaging system" means any system whereby a permanent or temporary image is recorded on an image receptor by the action of ionizing radiation. "Radiographic personnel" means any radiographer, radiographer instructor, or radiographer trainee, relative to industrial radiography. "Rating" means the operating limits as specified by the component manufacturer. "Recordable event" means the administration of: (1) An external beam radiation therapy dose when the calculated weekly administered dose is fifteen percent greater than the weekly prescribed dose; (2) A radiopharmaceutical or radiation without a written directive where a written directive is required; (3) A radiopharmaceutical or radiation where a written directive is required without daily recording of each administered radiopharmaceutical dosage or radiation dose in the appropriate record; (4) A therapeutic radiopharmaceutical dosage when the administered dosage differs from the prescribed dosage by more than ten percent of the prescribed dosage; (5) A teletherapy radiation dose when the calculated weekly administered dose is fifteen percent greater than the weekly prescribed dose; or (6) A brachytherapy radiation dose when the calculated administered dose differs from the prescribed dose by more than ten percent of the prescribed dose. "Recording" means producing a permanent form of an image resulting from x-ray photons. "Reference man" means a hypothetical aggregation of human physical and physiological characteristics determined by §11-45-2 45-24 international consensus. These characteristics may be used by researchers and public health workers to standardize results of experiments and to relate biological insult to a common base. "Reference plane" means a plane which is displaced from and parallel to the tomographic plane. "Regulations of the U.S. Department of Transportation" means the regulations in 49 C.F.R. Parts 100-189. "Rem" means the special unit of any of the quantities expressed as dose equivalent. The dose equivalent in rem is equal to the absorbed dose in rad multiplied by the quality factor (one rem = 0.01 sievert). "Research and development" means: (1) Theoretical analysis, exploration, or experimentation; or (2) The extension of investigative findings and theories of a scientific or technical nature into practical application for experimental and demonstration purposes, including the experimental production and testing of models, devices, equipment, materials, and processes. Research and development does not include the internal or external administration of radiation or radioactive material to human beings. "Residential location" means any area where structures in which people lodge or live are located, and the grounds on which such structures are located including, but not limited to, houses, apartments, condominiums, and garages. "Respiratory protective equipment" means an apparatus, such as a respirator, used to reduce an individual's intake of airborne radioactive materials. "Restricted area" means any area access to which is limited by the licensee for purposes of protection of individuals against undue risks from exposure to sources of radiation. A restricted area does not include areas used as residential quarters, but separate rooms in a residential building may be set apart as a restricted area. "Roentgen" (R) means the special unit of exposure. One roentgen (R) equals 2.58 x 10-4 coulombs per kilogram of air. (See "Exposure"). "Sanitary sewerage" means a system of public sewers for carrying off waste water and refuse, but excluding sewage treatment facilities, septic tanks, and leach fields owned or operated by the licensee. "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 preselected set of two or more scans performed consecutively under preselected CT conditions of operation. "Scan time" means the period of time between the beginning §11-45-2 45-25 and end of x-ray transmission data accumulation for a single scan. "Scattered radiation" means radiation that, during passage through matter, has been deviated in direction. (See "Direct scattered radiation"). "Sealed source" means radioactive material that is permanently bonded or fixed in a capsule or matrix designed to prevent release and dispersal of the radioactive material under the most severe conditions which are likely to be encountered in normal use and handling. "Secondary protective barrier" (See "Protective barrier"). "Shadow tray" means a device attached to the radiation head to support auxiliary beam limiting material. "Shallow dose equivalent" (Hs), which applies to the external exposure of the skin or an extremity, means the dose equivalent at a tissue depth of 0.007 centimeter (seven milligrams per centimeter squared) averaged over an area of one square centimeter. "Shielded-room radiography" means industrial radiography conducted in a room shielded so that radiation levels at every location on the exterior meet the limitations specified in subchapter 4 of these rules. "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. "SI" means an abbreviation of the International System of Units. "SID" (See "Source-image receptor distance"). "Sievert" (Sv) means the SI unit of any of the quantities expressed as dose equivalent. The dose equivalent in sievert is equal to the absorbed dose in gray multiplied by the quality factor (one sievert = one hundred rem). "Single tomogram system" means a CT x-ray system which obtains x-ray transmission data during a scan to produce a single tomogram. "Site boundary" means that line beyond which the land or property is not owned, leased, or otherwise controlled by the licensee. "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 material" means: (1) Uranium or thorium, or any combination thereof, in any physical or chemical form; or (2) Ores that contain by weight one-twentieth of one percent (0.05 percent) or more of uranium, thorium or any combination of uranium and thorium. Source material does not include special nuclear material. "Source material milling" means any activity that results in the production of byproduct material as defined by definition (2) of byproduct material. "Source of radiation" means any radioactive material or any device or equipment emitting, or capable of producing radiation. "Special form radioactive material" means radioactive §11-45-2 45-26 material which satisfies the following conditions: (1) It is either a single solid piece or is contained in a sealed capsule that can be opened only by destroying the capsule; (2) The piece or capsule has at least one dimension not less than five millimeters (0.197 inch); and (3) It satisfies the test requirements specified by the U.S. Nuclear Regulatory Commission. A special form encapsulation designed in accordance with the U.S. Nuclear Regulatory Commission requirements in effect on June 30, 1983, and constructed before July 1, 1985, may continue to be used. A special form encapsulation either designed or constructed after June 30, 1985, shall meet requirements of this definition applicable at the time of its design or construction. "Special nuclear material" means: (1) Plutonium, uranium-233, uranium enriched in the isotope 233 or in the isotope 235, and any other material that the U.S. Nuclear Regulatory Commission, pursuant to the provisions of section 51 of the Atomic Energy Act of 1954, as amended, determines to be special nuclear material, but does not include source material; or (2) Any material artificially enriched by any of the foregoing but does not include source material. "Special nuclear material in quantities not sufficient to form a critical mass" means uranium enriched in the isotope U-235 in quantities not exceeding three hundred fifty grams of contained U-235; uranium-233 in quantities not exceeding two hundred grams; plutonium in quantities not exceeding two hundred grams; or any combination of them in accordance with the following formula: For each kind of special nuclear material, determine the ratio between the quantity of that special nuclear material and the quantity specified above for the same kind of special nuclear material. The sum of such ratios for all of the kinds of special nuclear material in combination shall not exceed one. For example, the following quantities in combination would not exceed the limitation and are within the formula: 175(grams contained U-235)+ 50(grams U-233)+50(grams Pu) = 1 350 200 200 "Specific activity" of a radionuclide means the radioactivity of a radionuclide per unit mass of that nuclide. The specific activity of a material in which the radionuclide is essentially uniformly distributed is the radioactivity per unit mass of the material. "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 §11-45-2 45-27 intensifier for the purpose of making a radiograph. "SSD" means the distance between the source and the skin entrance plane of the patient. "Stationary beam therapy" means radiation therapy without relative displacement of the useful beam and the patient during irradiation. "Stationary x-ray equipment" (See "X-ray equipment"). "Stochastic effect" means a health effect that occurs randomly and for which the probability of the effect occurring, rather than its severity, is assumed to be a linear function of dose without threshold. Hereditary effects and cancer incidence are examples of stochastic effects. For purposes of these rules, probabilistic effect is an equivalent term. "Storage" means a condition in which a device or source is not being used for an extended period of time, and has been made inoperable. "Storage area" means any location, facility, or vehicle which is used to store, to transport, or to secure an x-ray system when it is not in use and which is locked or has a physical barrier to prevent accidental exposure, tampering with, or unauthorized removal of the device. "Stray radiation" means the sum of leakage and scattered radiation. "Survey" means an evaluation of the radiological conditions and potential hazards incident to the production, use, transfer, release, disposal, or presence of sources of radiation. When appropriate, such evaluation includes, but is not limited to, tests, physical examinations, and measurements of levels of radiation or concentrations of radioactive material present. "Target" means that part of a radiation head which by design intercepts a beam of accelerated particles with subsequent emission of other radiation. "Technique factors" means the following conditions of operations: (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 §11-45-2 45-28 and exposure time in mAs. "Temporary job site" means any location where industrial radiography is performed other than the location(s) listed on the license. "Termination of irradiation" means the stopping of irradiation in a fashion which shall not permit continuance of irradiation without the resetting of operating conditions at the control panel. "Test" means the process of verifying compliance with an applicable provisions of this chapter. "Tomogram" means the depiction of the x-ray attenuation properties of a section through a body. "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. "Total effective dose equivalent" (TEDE) means the sum of the deep dose equivalent for external exposures and the committed effective dose equivalent for internal exposures. "Transport index" means the dimensionless number, rounded up to the first decimal place, placed on the label of a package to designate the degree of control to be exercised by the carrier during transportation. The transport index is the number expressing the maximum radiation level in millirem per hour at one meter from the external surface of the package. "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. "Type A quantity" means a quantity of radioactive material, the aggregate radioactivity of which does not exceed A1 for special form radioactive material or A2 for normal form radioactive material. "Uncontrolled area" means any area access to which is not controlled by the licensee for purposes of protection of individuals from exposure to radiation and radioactive material, and any area used for residential quarters. "Unrefined and unprocessed ore" means ore in its natural form prior to any processing, such as grinding, roasting, beneficiating, or refining. "Unrestricted area" means an area, access to which is neither limited nor controlled by the licensee. For purposes of these rules, "uncontrolled area" is an equivalent term. "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. §11-45-2 45-29 "Very high radiation area" means an area, accessible to individuals, in which radiation levels could result in an individual receiving an absorbed dose in excess of five hundred rads (five grays) in one hour at one meter from a source of radiation or from any surface that the radiation penetrates. (At very high doses received at high dose rates, units of absorbed dose, rad and gray, are appropriate, rather than units of dose equivalent, rem and sievert.) "Virtual source" means a point from which radiation appears to originate. "Visible area" means that portion of the input surface of the image receptor over which incident x-ray photons are producing a visible image. "Waste" means those low-level radioactive wastes that are acceptable for disposal in a land disposal facility. For the purposes of this definition, low-level waste has the same meaning as in the Low-Level Radioactive Waste Policy Act, P.L. 96-573, as amended by P.L. 99-240, effective January 15, 1986; that is, radioactive waste (a) not classified as high-level radioactive waste, spent nuclear fuel, or byproduct material as defined in Section 11e.(2) of the Atomic Energy Act (uranium or thorium tailings and waste) and (b) classified as low-level radioactive waste consistent with existing law and in accordance with (a) by the U.S. Nuclear Regulatory Commission. "Waste handling licensees" mean persons licensed to receive and store radioactive wastes before disposal. "Week" means seven consecutive days starting on Sunday. "Weighting factor" wT for an organ or tissue (T) means the proportion of the risk of stochastic effects resulting from irradiation of that organ or tissue to the total risk of stochastic effects when the whole body is irradiated uniformly. For calculating the effective dose equivalent, the values of wT are: ORGAN DOSE WEIGHTING FACTORS Organ or Tissue wT ___________________________________ Gonads 0.25 Breast 0.15 Red bone marrow 0.12 Lung 0.12 Thyroid 0.03 Bone surfaces 0.03 Remainder 0.30a ___________________________________ Whole Body 1.OOb ____________________________________ a 0.30 results from 0.06 for each of five "remainder" organs, excluding the skin and the lens of the eye, that receive the highest doses. §11-45-2 45-30 b For the purpose of weighting the external whole body dose, for adding it to the internal dose, a single weighting factor, wT = 1.0, has been specified. The use of other weighting factors for external exposure shall be approved on a case-by-case basis until such time as specific guidance is issued. "Whole body" means, for purposes of external exposure, head, trunk including male gonads, arms above the elbow, or legs above the knee. "Worker" means an individual engaged in work licensed and controlled by a licensee, but does not include the licensee. "Working level" (WL) means any combination of short-lived radon daughters in one liter of air that shall result in the ultimate emission of 1.3 x 105 mega electron volts of potential alpha particle energy. The short-lived radon daughters are -- for radon-222: polonium-218, lead-214, bismuth-214, and polonium-214; and for radon-220: polonium-216, lead-212, bismuth-212, and polonium-212. "Working level month" (WLM) means an exposure to one working level for one hundred seventy hours -- two thousand working hours per year divided by twelve months per year is approximately equal to one hundred seventy hours per month. "Written directive" means an order in writing for a specific patient, dated and signed by an authorized user before the administration of a radiopharmaceutical or radiation, except as specified in (6) containing the following information: (1) For external beam radiotherapy, total dose, dose per fraction, treatment site and overall treatment period; or (2) For a therapeutic administration of a radiopharmaceutical; the radiopharmaceutical, dosage, and route of administration; or (3) For gamma stereotactic radiosurgery: target coordinates, collimator size, plug pattern, and total dose; or (4) For teletherapy: the total dose, dose per fraction, treatment site, and overall treatment period; or (5) For high-dose-rate remote afterloading brachytherapy: the radionuclide, treatment site, and total dose; or (6) For all other brachytherapy, before implantation: the radionuclide, number of sources, and source strengths; and after implantation but before completion of the procedure: the radionuclide, treatment site, and total source strength and exposure time (or, equivalently, the total dose). "X-ray exposure 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 such as timers and back-up timers. "X-ray equipment" means an x-ray system, subsystem, or §11-45-4 45-31 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 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, a tube housing assembly, a beam-limiting device, and the necessary supporting structures. Additional components which function with the system are considered integral parts of the system. "X-ray tube" means any electron tube which is designed to be used primarily for the production of x-rays. "Year" means the period of time beginning in January used to determine compliance with the provisions of these rules. The licensee may change the starting date of the year used to determine compliance provided that the change is made at the beginning of the year and that no day is omitted or duplicated in consecutive years. [Eff 11/12/99] (Auth: HRS §§321-10, 321-11, 321-71) (Imp: HRS §§321-1, 321-11(21), 321-71)