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Passive dosimeters have been extensively used to measure space radiation exposures to crewmembers for over three decades. Although a significant evolution in materials, processes, readout, and analysis techniques for these sensors has been witnessed during this period, these simple devices remain the backbone of the current operational dosimetry program for the Space Shuttle. Indeed, the utilization of passive dosimeters is also planned for the space station as well as advanced manned exploration programs, i.e., Lunar Base and Mars missions. Sensor materials and types have included thermoluminescent dosimeters, radiation-sensitive films and emulsions, and plastic nuclear track detectors. Early, transitional, and current passive dosimeter materials, systems, and techniques to measure space radiation are described and discussed, with major emphasis on the development of thermoluminescent dosimetry (TLD) techniques.

Longer on-orbit crew stay times anticipated during the construction and habitation of the International Space Station (ISS) will necessarily require the development of a new generation of radiation measurement instrumentation. The planned orbit of 51.6° inclination at 470 km will result in significantly higher daily crew exposures than experienced during the bulk of previous U.S. space missions. In addition, the National Commission for Radiation Protection and Measurement (NCRP) is revising the guidelines for crew radiation exposures. It is anticipated that the new guidelines will call for dose and dose-equivalent limits that are substantially less than those currently used in the space program. The cornerstone elements of the planned radiation measurement instrumentation for the ISS are a tissue-equivalent proportional counter (TEPC) and a directional charged particle spectrometer. These active systems will be supported by NASA's standard passive (thermoluminescent) dosimetry system.