Neutron spectrometry and dosimetry in specific locations at two CANDU power plants

Neutron monitoring was carried out in locations of interest to the health physics staff at two CANDU power plants in Ontario, Canada. Spectrometry and dosimetry were performed using Bonner sphere and TEPC systems, a moderator-type dose equivalent meter (a SNOOPY) and a damage track dosemeter (CR-39). The purposes of this investigation were to compare dose equivalent estimates from different measuring systems and to determine neutron fluence spectra for evaluation of instrument dose equivalent response. The fluence spectra were found to be fairly soft in general, with at least 50% of the total fluence falling below 200 keV. Relative to ambient dose equivalents derived from the Bonner sphere system, SNOOPY readings were typically 1 to 2 times larger, measured CR-39 values were within a factor of around 2 and measured TEPC data were 0.4 to 0.8 times as large. (Author)