This document consists of Copy No. TOR SECRET By authors -Conmiss Peme Joe 10 2 Serles B of U.S, Atomic , bok pages le Enerey~ i (bo © birdopp _-EGE, SECRET UNITED STATES ATOMIC ENERGY COMMISSION WASHINGTON 25, D.C, April 8, 1958 Dear Mr. Durham: rasanwwe F They are expected to give us valuable and essential information with respect to various effects that occur following a nuclear detonation above the greater portion of the earth's atmosphere, It is expected that the results of these tests will prove of great significance in the development of our defensive capabilities including possible defensive measures against intercontinental Yallistic missiles, Since the initial conception of these tests, we have, of course, studied exhaustively the. safety aspects of their conduct, One of these aspects concerns the distances to which the visible light from these explosions might cause damage to the human eye, Our first studies indicated that these distances were small N 0 eesi» fa ARS BY AUT! rydlioe aa ne z~ee : Ics DAgs I CEANGED te Fit im err ns al He Vl 9-5 Fe enough to be confined to our test area and therefore created no uncontrollable problem with respect to the safe conduct of the two tests, New theoretical calculations as to the amount of energy from these shots that will appear in the form of visible radiation have increased materially our estimate of the range at whichsome damage “might be caused to the human eye, This increased range includes a number of the inhabited atolls of the Marshall Islands... We have studied ways and means of controlling the conduct of these tests so as to insure that the natives of these islands could under no condition receive eye damage, We have, for instance, considered the stationing of American personnel, including Trust. Territory officials, on the various atolls and taking as positive measures. as possible to insure that no one was looking directly at the detonation at the time of its occurrence, However, it is felt that, despite an almost unlimited expenditure of our personnel RESTRICTED # This document contains