outside the general radiation field. However, the problem is more complex since the hands may come into contact with contaminated surfaces many times i larger in ares than the hands, with an undetermined percentage of activity being tran:ferred to the hards. Of course, an added uncertainty is the frequency of washing af the kencés and/or the rubbing off of the materiel from the hands. Further, one might speculate that a given surface could have sig- oy nificantly higher contamination than the general area and that the hand— ling of such a surface could constitute a greater risk. This might te | true beceuse of the greater amount of activity transferred to the hands or because of the doses delivered during the time of actually hindling the object. The uncerisinty of the percentage of trausfer of material has been nsntioned. Ome uncertainty in the second case is the lensth cf time the object would ts hendled. Bascd on calculations in appendices B snd D, when an object is held in a hand, a rough estixete of the ratio of dose rates of bets to the basal Isyer of the epidermis to that of the gamma reading con a survey meter held four inches away from an object two inches in radius (outside @ genera! radiation field) might be 5,000 to 1 (appendix I,). Thus, if a Phe: wesc bre this object were contaminated with the seme activity per unit area that would produce an infinity 10-rcoentgen whole-body gamma dose from general contamination of the area, it would produce ebout 50 mr/hr gamma at four inches away at H # 1 hours, and about 250 reps/hour at a depth of 7 mg/cem”.* Since the palms of the hands have an approximate epidermal layer of about 40 ng/em the beta dose to the basal layer would te about 170reps/hour,(Thetime of Ex lw elected to show about. the *These numbers agree fairly well with the computations in "Beta-contact Hazards Associated with Gamma-radiation Measurements of Mixed Fission Products", Teresi, J. D., USNRDL-383 (CONFIDENTIAL). Hi i: