External dosimetry and personnel monitoring

The early history of our profession, as well as the discoveries that form its foundations, provide an interesting background on which to assess our progress in measuring exposure to ionizing radiation (i.e., dosimetry). One of the first challenges faced by scientists working with radiation and radioactivity was appropriate measurement techniques. Frame (2004) has provided an excellent review of the history and development of radiation detection techniques and devices. In the early 20th century, some of these techniques were extended to measurements of the doses received by the individual scientists although it is not known exactly when organized personnel monitoring actually began. This manuscript will discuss some of the history of external dosimetry (specifically personnel monitoring), consider the developments that led to improved monitoring, attempt to assess the current status of the field and, also, to try to predict the future. The focus of this review will be primarily on personnel monitoring or personnel dosimetry. Obviously, it will not be possible to discuss every development in the field in detail and some choices have been made as to what to include and what to ignore. The author takes full responsibility for these choices. However, the goal is to provide sufficient coverage that the current situation and the future of personnel monitoring can be understood in the context of past developments. The discussion of the current status of external dosimetry will include some recent developments that hold great promise. In addition, a concern will be raised regarding the interpretation of the current U.S. federal regulations and the impact of the regulations on personnel dosimetry. Finally, there will be a discussion of what the future may hold in terms of the types of dosimeters and the approaches to personnel monitoring, in particular.