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milliroentgens in one hour when the tube is operated at any of the tube’s specified ratings;
(21) “diaphragm” means a beam restricting device that is made of a flat piece of attenuating material with an aperture that restricts the useful beam;
(22) “dose”
(A) means
(i)the quantity of radiation absorbed, per unit of mass,…#
(i) the quantity of radiation absorbed, per unit of mass, by the whole body or by any portion of the body;
(ii)in connection with a period of time, the total quantity…#
(ii) in connection with a period of time, the total quantity of radiation absorbed, per unit of mass, during that period of time;
(B) includes
(i) absorbed dose;
(ii) committed dose equivalent;
(iii) committed effective dose equivalent;
(iv) dose equivalent;
(v) effective dose equivalent; and
(vi)total effective dose equivalent;#
(vi) total effective dose equivalent;
(23) “dose equivalent” means the product of the absorbed dose in tissue, quality factor, and all other necessary modifying factors at the location of interest, and a unit of which is the rem and sievert;
(24) “effective dose equivalent” means the sum of the products of the dose equivalent to the organ or tissue and the weighting factors applicable to each of the body organs or tissues that are irradiated;
(25) “enclosure” means a cabinet, box, or other container, provided by the manufacturer or user of a radiation machine, from which the source of the radiation cannot be removed without destroying the function of the source;
(26) “exposure” means being exposed to ionizing radiation or to radioactive material;
(27) “FDA” means the Food and Drug Administration;
(28) “field radiography” means industrial radiography using ionizing radiation machines, except for cabinet radiography and shielded room radiography;
(29) “filter” means material placed in a useful beam to preferentially absorb less penetrating radiations;
(30) “gray” means the SI unit of absorbed dose that is equal to an absorbed dose of one