Application of different TL detectors for the photon dosimetry in mixed radiation fields used for BNCT.

Different approaches for the measurement of a relatively small gamma dose in strong fields of thermal and epithermal neutrons as used for Boron Neutron Capture Therapy (BNCT) have been studied with various thermoluminescence detectors (TLDs). CaF(2):Tm detectors are insensitive to thermal neutrons but not tissue-equivalent. A disadvantage of applying tissue-equivalent (7)LiF detectors is a strong neutron signal resulting from the unavoidable presence of (6)Li traces.

Experience in long-term neutron dose equivalent measurements using etched track detectors with (n,alpha) converters in moderators.

Etched track Makrofol detectors combined with Kodak BN-1 boron (n,alpha) converters were used inside a 30 cm diameter polyethylene (PE) sphere for the measurement of the neutron ambient dose equivalent. We found unexpectedly high values for the neutron dose equivalent of about 250 microSv instead of 25 microSv for 3 months' exposure in the natural environment. Results from such detectors etched in the authors' labortories revealed that the tracks could only be induced by spontaneous particle emission from the converter.

[The use of thermoluminescent dosimetry systems in individual dosimetry and environmental monitoring].

A brief survey is given of the application of TLD systems, above all in neutron dosimetry, dosimetry in the irradiation of body parts and beta-radiation as well as in the environment monitoring. Recent communications of literature are mentioned, also concerning the practical application of thermoluminescent dosimetry in the cited fields.