Tissue-equivalent proportional counters in radiation protection dosimetry: expectations and present state

A survey is given of the application of low-pressure tissue-equivalent proportional counters (TEPC) in radiation protection dosimetry. The original motivation to use this technique and the related expectations are reviewed and the properties of instruments already available are evaluated. The numerous measurements carried out with such instruments in the past few years in various radiation fields show the large demand for 'intelligent' survey instruments. The implications of the new ICRP recommendation for the quality factor on the operational characteristics of TEPC-based instruments are investigated by re-evaluation of results from an intercomparison. It is shown that a simple modification of the evaluation procedure will make it possible to cope with the new situation. (author)