Dosimetry serves important functions in radiation processing, where large absorbed doses and dose rates from photon and electron sources have to be measured with reasonable accuracy. Proven dosimetry systems are widely used to perform radiation measurements in development of new processes, validation, qualification, and verification (quality control) of established processes and archival documentation of day-to-day and plant-to-plant processing uniformity.
Proper calibration and traceability of routine dosimetry systems to standards are crucial to the success of many large-volume radiation processes. Recent innovations and advances in performance of systems that enhance radiation measurement assurance and process diagnostics include dosemapping media (new radiochromic film and solutions), optical waveguide systems for food irradiation, solid-state devices for real-time and passive dosimetry over wide dose-rate and dose ranges. and improved analytical instruments and data acquisition. Calibration; dose mapping; dosimetry systems; electron processing; gamma-ray processing; highdose dosimetry: novel dosimeters: radiochromic dosimeters; solid-state dosimeters INTRODL!CTION Industrial radiation applications of ionizing radiation sources of photons (x-and gamma rays) and electrons (accelerators) encompass a wide range of absorbed doses. D (about six orders of magnitude), dose rates, a (twelve orders of magnitude), and energies, E (over two orders of magnitude.
It is the quantity. D. that must be measured (or calculated) by dosimetry (or computational characterization of parameters) (McLaughlin rr (II., 1989a;Seltzer and Berger, 1987;McKeown and Drewell, 1994). The aim here is to feature essential dosimetry concepts and advances which have arisen since the IMRP8 meeting in Beijing (Huang Qitao et al., 1993). Table 1 gives a synopsis of systems. read-out methods, and useable dose ranges.
*The mention of commrrclal products throughout this paper does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the products identified are necessarily the best available for the purpose.