title: Practical implications of neutron survey instrument performance.
abstract: Improvements have been made to the Monte Carlo modelling used to calculate the response of the neutron survey instruments most commonly used in the UK, for neutron energies up to 20 MeV. The improved modelling of the devices includes the electronics and battery pack, allowing better calculations of both the energy and angle dependence of response. These data are used to calculate the response of the instruments in rotationally and fully isotropic, as well as unidirectional fields. Experimental measurements with radionuclide sources and monoenergetic neutron fields have been, and continue to be made, to test the calculated response characteristics. The enhancements to the calculations have involved simulation of the sensitivity of the response to variations in instrument manufacture, and will include the influence of the user and floor during measurements. The practical implications of the energy and angle dependence of response, variations in manufacture, and the influence of the user are assessed by folding the response characteristics with workplace energy and direction distributions.
authors.affiliation: National Radiological Protection Board, Chilton, Didcot, Oxon OX11 0RQ, UK. rick.tanner@nrpb.org
authors.forename: R J
authors.initials: RJ
authors.lastname: Tanner
authors.forename: D T
authors.initials: DT
authors.lastname: Bartlett
authors.forename: L G
authors.initials: LG
authors.lastname: Hager
authors.forename: L N
authors.initials: LN
authors.lastname: Jones
authors.forename: C
authors.initials: C
authors.lastname: Molinos
authors.forename: N J
authors.initials: NJ
authors.lastname: Roberts
authors.forename: G C
authors.initials: GC
authors.lastname: Taylor
authors.forename: D J
authors.initials: DJ
authors.lastname: Thomas
mesh_terms: D000465:Algorithms; D001822:Body Burden; D002138:Calibration; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis / Q000379:methods*; D006801:Humans; D009502:Neutrons; D016273:Occupational Exposure / Q000032:analysis*; D011785:Quality Assurance, Health Care / Q000379:methods; D011829:Radiation Dosage; D011835:Radiation Protection / Q000295:instrumentation* / Q000379:methods; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D012062:Relative Biological Effectiveness; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods* / Q000639:trends; D012307:Risk Factors; D017751:Safety Management / Q000379:methods; D012680:Sensitivity and Specificity