4.1.1 Overall supervisor must keep constant watch to see that personnel do not inadvertently remain for long times close to high inten- sity sources of radiation such as filter units, "cave" with filter paper in it, box with empty filter holders and scrap safety wire, or filled pigs on trailer number three, He must monitor positions of personnel relative to each other and their handling of removal tools so that "hot" tools do not accidently touch personnel, He must insure that casual observer personnel do not get in way of removal operations, In case of accident or equipment failure, supervisor mist determine appropriate action to be taken, Caution: In no case is it permissable for personnel to use their hands (even protected by leather palmed gloves) to restrain or maneuver "hot" filter paper, 4.2 Information, 2.1 A single filter paper from a B-57B aircraft may frequently have a gamma radiation intensity of 100 rfhr at one foot. At 25 feet the back~ ground radiation intensity from this source alone will be approximately 0.5 r/hr, Distances from aircraft for trailer and for personnel positions mst be chosen as compromise between high background radiation and time required for critical operations such as carrying the filter in filter holder from airplane to cave, The success of removal operations as described above represents compromises between protection by shielding or by distance from source and time required to perform operations swiftly and safely, The basic philosophy underlying this operation, as for other phases of sampling, - is that radiation exposures will be held to the minimum practicable to accomplish the job. In general, Los Alamos scientists held that once experienced personnel were transferred or disbanded, the task for rebuilding a sampling unit would be difficult if testing resumed after sporadic periods, “unique and existed for highly specified conditions, 225 AFWUt The function was Of necessity, many SWEH-2-0034 pt