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(81) “shallow-dose equivalent whole body” means the dose equivalent at a tissue depth of 0.007 centimeter based on the external radiation exposure of the skin of the whole body;

(82) “shielded room radiography” means industrial radiography, with the use of ionizing radiation machines, that is conducted in an enclosed room, in which

(A) the interior is not occupied during radiographic operations;

(B) is shielded so that every location on the exterior meets conditions for an uncontrolled area as specified in 7 AAC 18.240; and

(C) the only access is through openings which are interlocked so that the ionizing radiation machine will not operate unless all openings are securely closed;

(83) “shutter” means an adjustable device, generally consisting of lead, fixed to an x-ray tube housing to intercept the useful beam;

(84) “sievert” means the SI unit of any of the quantities expressed as dose equivalent, in which the dose equivalent is equal to the absorbed dose in grays multiplied by the quality factor;

(85) “source material”

(A) means uranium or thorium, or any combination of uranium or thorium, in any physical or chemical form or ores which contain 0.05 percent or more of uranium, thorium, or any combination of them;

(B) does not include special nuclear material;

(86) “special nuclear material” means Uranium233, Uranium235, and plutonium;

(87) “stochastic effects” means health effects, including hereditary effects and cancer incidence, 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;

(88) “stray radiation”

(A) means radiation not serving any useful purpose; and

(B) includes leakage radiation and scattered radiation;

(89) “survey”

(A) means an evaluation of radiation protection practices;

(B) includes