In addition, task group personnel were to be guided by Navy Instruc~ tions USF 82 and 85, which dealt with standard decontamination procedures and contaminated waste disposal TASK GROUP 7.4. (Reference 12, Annex G). Each unit of TG 7.4 was required to train radsafe monitors, including one airborne monitor for each multiengine aircraft. Although all assigned personnel were supposed to receive basic radsafe training, there is no indication that this actually occurred. SAFETY CRITERIA Radsafe criteria based on AEC industrial safeguards were approved by the Surgeons General of the Army and Air Force, the Chief of the Navy Bureau of Medicine and Surgery, and the Director, AEC Division of Biology and Medicine. uations aS CJTF 7 disseminated operational rules for radiological sit- an Annex to the JTF 7 Operation Order (Reference 19). Each task group implemented the annex with its own orders or plans. The radsafe criteria measuring units were the roentgen (R) and the rem. The roentgen, a meaSure of radiation in air, denotes an exposure intensity. The rem is a unit of radiation dose, i.e., a measure of radiation energy deposited within the body that takes into account its capability of causing an effect. It is measurable in fractions of a rem, such as a millirem (mrem), which is 1/1,000th of a rem. For most forms of ionizing radiation, such as beta and gamma, the rem dose is less than the roentgen exposure, for not all of the energy measurable in air penetrates body tissues. ther unit often used in discussing radiation doses is the rad. Ano- The rad is a Measure of radiation energy deposited in any material; for biological tissue, a rad of low-quality radiation such as from gamma- or X-rays es- sentially equals a rem. At the time of the CASTLE series the distinction was usually not made between exposure dose (properly expressed in units of roentgens) and absorbed (properly expressed in units of rem, although at the time often ex- pressed in roentgens); presumably external whole-body exposure and absorbed dose were assumed equivalent. This history expresses the measured data in 94