R J Tanner, D J Thomas, D T Bartlett, L G Hager, N Horwood and G C Taylor
Publication date: September 2002
A large set of neutron energy distributions was classified by workplace to provide sets of neutron fields to which workers in particular industries may be exposed. These were folded with personal dosemeter response characteristics to determine the systematic errors in values of neutron personal dose equivalent that those dosemeters would give in workplaces. Data for neutron effective dose equivalent recorded for UK classified workers have been taken from the Central Index of Dose Information (CIDI) reports for the years from 1990 to 2001, and related to the results from the folding process. Hence, it has been possible to determine the probable systematic errors that result from the use of the currently available neutron personal dosemeters.
The main conclusions that may be drawn from this work are as follows.
Consequently, in terms of the practical implications it is possible to state that there is no evidence of widespread restrictions on working practice caused by the energy dependence of response of neutron personal dosemeters; overestimates of dose will be infrequent. There is, however, significant potential for underestimates of dose because dosemeters fail to detect with adequate efficiency the whole energy range of workplace neutron spectra. The most significant influence that this may have is on the reporting of false negative doses rather than the underestimation of reported doses.
The study has been hampered by the limited availability of measured or calculated UK workplace energy distributions. Some workplaces are poorly covered by measured or calculated energy distributions that are in the public domain. Difficulties were also encountered in linking CIDI workplace categories to working practices.
Areas that require further study are listed below.
Last reviewed: 29 July 2009