states "It appears, then, that strontium 9° is not a current threat, but if there were any substantial increase in the rate of contamination of the atmosphere, it could become one." The conclusions are to all intents and purposes identical to those of the National Academy of Sclences report, 1. Adequate justification should be required for the employment of any source of ionizing radiation on however small a scale. This is not explicitly stated in the National Academy of Sciences report but is inherent in it. 2, Dose levels to the individual - 0,3r per week - 200r in a lifetime for occupational exposures and no more than 50r the first 30 years of life, 3.No more than twice natural background from manmade sources for the population as a whole, 4, The present and foreseeable hazards from external radiation due to fallout at present rate of testing 18 insignificant, As to internal hazards from strontium at its present level no detectable increase in the incidence of ill-effects is to be expected, "Nevertheless, recognizing all the inadequacy of our present knowledge, we cannot ignore the possibility, that if the rate of firing increases and particularly if greater numbers of thermonuclear weapons are used, we could within the life~ time of some now living, be approaching levels at which lil-effects might be produced in a small number of the population,” This is a rather roundabout way of saying, "let's be careful,” 5. a, All sources of radiation should be under close inspection, A personal record not only of doses of radiation received during occupation but also of exposure from all other sources such as medical diagnostic radiology should be kept for all persons whose occupation exposes them to additional sources of radiation, The National Academy of Seiences report would seem to include the whole population in its Similar recommendations, b. Present practices in medical diagnostic radiology should be reviewed with the object of clarifying the indications for different special types of examination now being carried out and defining more closely, both in relation to the patient and to the operators, the conditions which should be observed in their performance. This says, in effect, "let's tighten up on unnecessary exposures," ec, The uses of radiotherapy in non-malignant conditions should be critically examined--again, a Warning to tighten up on unnecessary exposures, - 22 - Enclosure III