aL Joint Task Force SEVEN ins Task Group 7.3 Washington 25, D. C. 7 December 1953, 1200R Appendix V to Annex G Additional RadSafe Measures Directed for Shot Times Y9 FolderTE 7 CT6 73-OPEeATIDN Prawn cr No./ 53q w om i. If decks and structures are kept wet prior to fallout there is less likeihiood of radioactive fallout being absorbed into porous materials and cracks. oD. Access No. 6/A 1740 Box oye Location AGENy “’ 374 DerBwse Nuctgan Operation plan. G 7.3 No. 1-53 In addition to RadSafe Instructions listed elsewhere, it is directed that ships within eighty miles of the shot site from D Day to D/2-day observe following procedures: a. From H410 minutes to H+h hours: _ (1) Clear topsides of all non-essential personnel. (2) Close all doors, hatches, and ports from topside to the interior of the ship. (3) Continue to operate the ventilation systems at the discretion of the Commanding Officer, but monitor air coming from topside. (4) Keep the washdown equipment ready for immediate use. (5) Maintain the topside in a wet condition by continuous or intermittent use of the washdown system. In order to avoid grounding numerous antennas, ESTES shall not use the washdown system until and unless fallout is detected. (6) Maintain a constant watch for radioactive fallout on topsides except when washdown system is turned on. b. From H/4 hours to H448 hours (1) Keep the washdown system ready for immediate use, except when this interferes with essential ship activities. 3. AIL TG 7.3 ships in the =NIWETOK/BIKINI Danger Area shall: a. From H/4 hours to Hf36 hours, check the topsides for radioactive fallout every twenty minutes... b. From H4/36 hours to H/72 hours, check the topsides for radioactive DNA. every hour, c. From H/72 hours to D plus7 days, check the topsides for radioactive fall- out every four hours. d. Maneuver to avoid rainfall and low clouds, as practicable. ~<a ora CHM M9!