Chapter 4—Monitoring Accidental Radiation Releases @ 67 Figure 4-6—Typical RAMsArray for Tunnel Shot (‘Mission Cyber,” Dec. 2, 1988) Surtace Locations Subsurface Locations @ RAM Locations Scale -—4 = 200 A total of 41 RAMs (15 abovethe surface, 26 belowground) are used to monitor the containmentof radioactive material from a horizontal tunnel test. SOURCE: Modified from Department of Energy. Thermoluminescent Dosimeter (TLD): When heated (thermo-), the TLD releases absorbed energy in the form oflight (-luminescent). The intensity of the light is proportional to the gammaradiation absorbed, allowing calculation of the total gamma radiation exposure. GammaRadiation Exposure Rate Recorder: A pressurized ion chamberdetector for gammaradiation is connected to a recorder so that a continuous record of gammaradiation is obtained and changes in the normal gammaradiation level are easily seen. Microbarograph: This instrument measures and records barometric pressure. The data are useful in interpreting gammaradiation exposure rate records. At lower atmospheric pressure, naturally occurring radioactive gases (like radon) are released in greater amounts from the Earth’s surface and their radioactive decay contributes to total radiation exposure.