DHS 157.03(70)(a)(a) A radiation shield that is placed on the end of the guide tube or directly onto a radiographic exposure device to restrict the size of the radiation beam when the sealed source is moved into position to make a radiographic exposure.

DHS 157.03(71)(71) “Commission” means the United States nuclear regulatory commission.

DHS 157.03(72)(72) “Committed dose equivalent” or “CDE” means the dose equivalent to organs or tissues of reference that will be received from an intake of radioactive material by an individual during the 50-year period following the intake.

DHS 157.03(73)(73) “Committed effective dose equivalent” or “CEDE” 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.

DHS 157.03 NoteNote: Committed effective dose equivalent (HE,50) equals the sum of the weighting factor (wT,) times the committed dose equivalent (HT,50).

DHS 157.03(74)(74) “Computed tomography” or “CT” means the production of a tomogram by the acquisition and computer processing of x-ray transmission data.

DHS 157.03(75)(a)(a) “Computed tomography dose index” or “CTDI” means the integral from -10T to +10T 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, that is:

DHS 157.03(75)(b)(b) The definition of “computed tomography dose index” assumes that the dose profile is centered around z=0 and that, for a multiple tomogram system, the scan increment between adjacent scans is nT.

DHS 157.03(75m)(75m) “Consignment” means each shipment of a package or groups of packages or load of radioactive material offered by a shipper for transport.

DHS 157.03(75r)(75r) “Consortium” means an association of medical use licensees and a PET facility in the same geographical area, physically located at an educational institution, a federal facility or a medical facility, that jointly own or share in the operation and maintenance cost of the PET facility that produces PET radionuclides for use in producing radioactive drugs within the consortium for noncommercial distributions among its associated members for medical use.

DHS 157.03(76)(76) “Constraint” means a value above which specified licensee or registrant actions are required.

DHS 157.03(77)(77) “Contact therapy system” means a therapeutic radiation machine with a short target to skin distance, usually less than 5 centimeters.

DHS 157.03(77m)(77m) “Contamination” means the presence of a radioactive substance on a surface in quantities in excess of 0.4 Bq/cm2 (1x10-5 microcurie/cm2) for beta and gamma emitters and low toxicity alpha emitters, or 0.04 Bq/cm2 (1x10-6 microcurie/cm2) for all other alpha emitters.

DHS 157.03(78)(78) “Control cable” means the cable that is connected to the source assembly and used to drive the source to and from the exposure location.

DHS 157.03(79)(79) “Control drive mechanism” means a device that enables the source assembly to be moved into and out of the exposure device.

DHS 157.03(80)(80) “Control panel” means that part of an x-ray control upon which are mounted the switches, knobs, pushbuttons and other hardware necessary for manually setting the technique factors.

DHS 157.03(81)(81) “Control tube” means a protective sheath for guiding the control cable. The control tube connects the control drive mechanism to the radiographic exposure device.

DHS 157.03(82)(82) “Controlled area” means an area, outside of a restricted area but inside the site boundary, access to which may be limited by the licensee or registrant for any reason.

DHS 157.03(82m)(82m) “Conveyance” means any one of the following:

DHS 157.03(82m)(a)(a) For transport by public highway or rail, any transport vehicle or large freight container.