The MPE's do not represent limits within which there can be a complete disregard of exposure. (The exposure to ionizing radiation should be kept to an absolute minimum in all circumstances.) Radsafe Instrumentation ares The majority of the TU 7,monitor ing was done with the AN/POR-T1B ion chamber (IPO 132.1TU1#615, p. 29). on loan from AFSWP. Fifty-five of these instruments were The instrument electronics had been modified atthe Nevada Test Site to eliminate switching transients resulting from changes in scale. A new ion-chamber instrument developed by the Army Signal Corps, IM-71/PD(XE-1), called the "Jasper," was tested and used after humidity leaks were corrected. available to the task force. Twenty-five of these instruments were A letter to CTG 132.4 indicated that "for some instruments" the meter needle would not return to zero when subjected to high temperature. , This would not affect the reading above 1 R/hr but . . Persona ev mnAAT could cause some inaccuracies in the lower ranges. [Was dene or. a Hats with the MX-5 and AN/POR-T27 Geiger-Mueller instruments. Table 2.3 lists the instruments used by TG 132.3. In order to protect vessels from contamination by radioactive material in lagoon waters, periodic samples were collected from the lagoon, analyzed in the laboratory van aboard the Rendova, and, in the event contamination was indicated, CTG 132.3 was notified. 2-43 s