| (87) Radiograph--An image receptor on which the image is created directly or indirectly by an x-ray exposure and results in a permanent record. (88) Registrant--Any person issued a certificate of registration by the agency in accordance with the Act and this chapter. (89) Regulation--(See definition for rule.) (90) Rem--The special unit of any of the quantities expressed as DE. The DE in rem is equal to the absorbed dose in rad multiplied by the quality factor (1 rem = 0.01 sievert (Sv)). (91) Remote inspection--An examination by the agency of information submitted by the registrant on a form provided by the agency. (92) Research and development--Research and development is defined as: (A) theoretical analysis, exploration, or experimentation; or (B) 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. (93) Restricted area--An area, access to which is limited by the registrant for the purpose of protecting individuals against undue risks from exposure to radiation. 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. (94) Roentgen (R)--The special unit of exposure. One roentgen (R) equals 2.58 x 10-4 C/kg of air. (See definition for exposure.) (95) Rule--Any agency statement of general applicability that implements, interprets, or prescribes law or policy, or describes the procedure or practice requirements of an agency. The term includes the amendment or repeal of a prior section but does not include statements concerning only the internal management or organization of any agency and not affecting private rights or procedures. The word "rule" was formerly referred to as "regulation." (96) Scan--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. (97) Scan time--The period of time between the beginning and end of x-ray transmission data accumulation for a single scan. (98) Scattered radiation--Radiation that has been deviated in direction during passage through matter. (99) Secondary protective barrier--(See definition for protective barrier.) (100) Severity level--A classification of violations based on relative seriousness of each violation and the significance of the effect of the violation on the occupational or public health or safety or the environment. (101) Shallow dose equivalent (SDE)--The DE at a tissue depth of 0.007 cm (7 mg/cm2 ) that applies to the external exposure of the skin of the whole body or the skin of an extremity. (102) Shutter--A device attached to the tube housing assembly that can totally intercept the useful beam and that has a lead equivalency not less than that of the tube housing assembly. (103) SI--The abbreviation for the International System of Units. (104) Sievert (Sv)--The SI unit of any of the quantities expressed as DE. The DE in sievert is equal to the absorbed dose in gray multiplied by the quality factor (1 Sv = 100 rem.) (105) Source--The focal spot of the x-ray tube. (106) Source of radiation--Any radioactive material, or any device or equipment emitting or capable of producing radiation. (107) Source-to-image receptor distance (SID)--The distance from the source to the center of the input surface of the image receptor. (108) Source-to-skin distance (SSD)--The distance from the source to the skin of the patient. (109) Special units--The conventional units historically used by registrants, for example, rad (absorbed dose), and rem (DE). (110) Spot film--A radiograph that is made during a fluoroscopic examination to permanently record conditions that exist during that fluoroscopic procedure. (111) Stationary x-ray equipment--(See definition for x-ray equipment.) (112) Stray radiation--The sum of leakage and scattered radiation. (113) Supervision--The delegating of the task of applying radiation in accordance with this section to persons who perform tasks under the veterinarian's control. The veterinarian assumes full responsibility for these tasks and shall assure that the tasks will be administered correctly. (114) Survey--An evaluation of the radiological conditions and potential hazards incident to the production, use, transfer, disposal, and/or presence of radiation machines. When appropriate, such survey includes, but is not limited to, tests, physical examination of location of equipment, measurements of levels of radiation present, and evaluation of administrative and/or engineered controls. (115) Technique chart--A chart that provides all necessary generator control settings and geometry needed to make clinical radiographs when the radiography system is in manual mode. (116) Technique factors--The conditions of operation that are specified as follows: (A) for capacitor energy storage equipment, peak tube potential in kV and quantity of charge in mAs; (B) for field emission equipment rated for pulsed operation, peak tube potential in kV and number of x-ray pulses; (C) for CT equipment designed for pulsed operations, 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; (D) for CT equipment 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 when the scan time and exposure time are equivalent; and (E) 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. (117) Termination--A release by the agency of the obligations and authorizations of the registrant under the terms of the certificate of registration. It does not relieve a person of duties and responsibilities imposed by law. (118) Texas Regulations for Control of Radiation (TRCR)--All sections of Title 25 Texas Administrative Code (TAC), Chapter 289. (119) Total effective dose equivalent (TEDE)--For external exposures only to x-ray radiation from radiation machines, the TEDE is equal to the DDE. If an individual receives an occupational dose from both radiation machines and radioactive materials, the TEDE is the sum of the DDE for external exposures and the committed effective dose equivalent for internal exposures as defined in §289.201(b) of this title. (120) Tube--An x-ray tube, unless otherwise specified. (121) Tube housing assembly--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. (122) Unrestricted area (uncontrolled area)--An area, access to which is neither limited nor controlled by the registrant. For purposes of this chapter, "uncontrolled area" is an equivalent term. (123) Useful beam--Radiation that passes through the window, aperture, cone, or other collimating device of the source housing. Also referred to as the primary beam. (124) Veterinarian--An individual licensed by the Texas Board of Veterinary Medical Examiners. (125) Very high radiation area--An area, accessible to individuals, in which radiation levels from radiation machines external to the body could result in an individual receiving an absorbed dose in excess of 500 rads (5 grays) in one hour at 1 meter (m) from a radiation machine or from any surface that the radiation penetrates. At very high doses received at high dose rates, units of absorbed dose, gray and rad, are appropriate, rather than units of DE, Sv and rem. (126) Violation--An infringement of any rule, license or registration condition, order of the agency, or any provision of the Act. (127) Whole body--For purposes of external exposure, head, trunk including male gonads, arms above the elbow, or legs above the knee. (128) Worker--An individual engaged in work under a certificate of registration issued by the agency and controlled by a registrant, but does not include the registrant. Cont'd... |
