APPENDIX E STANDARD OPERATING PROCEDURE eration of each counting setup will be checked by the daily determination of standard factors Ma eats ease and periodic determination of chi-square values. The nine-tenths error of the raw counts wil! be maintained at a level below 1 per cent. The over-all precision of the results will be held to a maximum spread of +5 per cent. Results will be reported on standardized forms to RIC. 83 ae The mission of the Radiological Field Laboratory is to perform radiological assays of liquids, solids, and airborne particulate matter for the Rad-Safe Officer in connection with the health-physics program of Operation Ivy. The following discussion will indicate how this mission will be accomplished. Samples will be received aboard the USS Rendova, where the field laboratory is stationed. These will ke monitored, and representative samples will be taken for assay. The techniques to be followed will vary with the data desired and the type of sample submitted. The standard operating procedures described in detail in the “Manual for the Radiological Field Laboratory” will be adhered to. Expected samples include salt water from the Eniwetok Lagoon, fresh water from the effluents of drinking-water purification plants, soil taken at various distances from ground zero, and airborne material collected on filter paper and cascade-impactor slides. Thefield laboratory will determine, as requircd, the activity of alpha, beta, and gamma radiations; the energy of beta and gammaradiations; and the decay rates of the various activities. Beta and gamma measurementswill be taken primarily by means of end-window G-M tubes coupled to either decade or binary scalers. Rough and rapid gamma activities can also be obtained by dip counting using a Marinelli type beaker coupled to a scaler. Alpha activities will be measured with a scintillation counter plus a scaler. Beta energies will be obtained by Feather analysis using aluminum absorbers; gamma energies will be determined with lead absorbers. Decay rates will be primarily determined by manual counting at definite time intervals. Rapidly decaying activities will, however, be followed with a counting rate meter and automatically recorded. The accuracy of the data will be ensured by calibration against standard sources. The op- Pe aNpeering of FOR RADIOLOGICAL FIELD LABORATORY