topside give the shielding factor for deposited contamination. Ixtra- polation of this factor to earlier times will give an estimate of the | shielding factor for deposited contamination during the event~-and hence of the dose rate in shielded locations due to contamination. The difference between this value and that actually recorded gives the estimated dose rate from airborne activity. The ratio of the shielded dose rate for airborne activity to the unshielded value then gives the shielding factor for airborne activity. Continuous dose-rate measurements will be made on deck inside a series of 8 pipes of varying thicknesses. Details are given in Tab B. From these data, absorption curves can be made for any time after activity has arrived at the snip, to give an estimate of the effective photon energy for transmission through steel. This information will be used in corre- lating computed with experimental values. 3.2 Total Dose Measurements As a check on integrated doses, simple integrating dosimeters of the film badge type will be installed at the same locations. Ratios of total doses at shielded locations to those at unshielded locations will give an overall shielding factor. However, this factor is applicable only to the particular conditions of the test. 5.3 Gamma Field Surveys Gamma field surveys topside will be made in connection with Project 6.4a. In addition, similar surveys will be made in interior compartments for two reasons. First, compartments where instruments are located x.sill be surveyed to determine the magnitude and nature of variation in the radietion field. Second, to check on the recorded dose rates and to extend decay-rate data, dose rates will be measured as soon as possible at the locations of the recording instruments, and thereafter at intervals for as long as is practicable. 4. ADUISISTRaTIVE AND LOGISTICAL MATTORS Rollup) 4.1 (Test Preparation, Support and Pre-Test Work at USNRDL 4.2.1 Ship Shielding Characteristics For correlation with the test results, a simplified shielding experiment using a source of known energy will be conducted at USNRDL. For details of this experiment see Tab C by the Nucleonics Division. 4.1.2 Instruments ST, LOUIS FRC Fixed gamma recording instruments are being developed by the JRDL Laboratory Instrumentation Branch. Standard dosimetric devices and raciac sets will be used for thetotal dose and survey measurements. 4 ee