i.SEI (20%) Project 2.71 - Relative Importance of the Various Radiation Sources to the Ship Shielding Problem - H. R. Rinnert OBJECTIVES | To determine the relative radiation dose rates contributed by contamination of the air envelope, water envelope, and the ship's weather surfaces, To determine the time dependent gamma ray combined absorption and seattering coefficients of stecl to be used in future calculations of shielding effectiveness, Te ficli test new ani improved detector systems. To obtain gamma radiation measurements at various points on and in the ship as a function of timc for the following purposes: Cheek points for future shielding calculations. Petermination of the radislogical situation at various locations aboard ship for Projects 2.63 and 2.10, to be used for Operational control of the test ships. INSTRUMTT ATION YAG-40 received enough contamination to supply data to satisfy all objectives. Only YAG-40 data have been reduced to date. The in- strumontation performed satisfactorily. RUSULTS Relative Gamna Radiation Fielis Contributed by Various Radiation Sources "Free field" measurements were compared, these free fields are defined as follows: Water free field - 4 pi radiation field at a water COMIP eae 3 L ~ 50 = QI depth of between 20 and 30 feet; Air free field - 2 pi radiation field

Select target paragraph3