BS ISO 20785-4:2019 pdf free

BS ISO 20785-4:2019 pdf free.Dosimetry for exposures to cosmic radiation in civilian aircraft
The ambient dose equivalent calculated by the codes shall be validated by a comparison with measured or reference data. The general approach is to perform a comparison with a selection of data from a representative selection of routes with a range of altitude, latitude, longitude and solar activity. The dose measurements shall be performed according to the other parts of the ISO 20785 series, i.e. ISO 20785-1, ISO 20785-2 and ISO 20785-3.
ICRU has published reference values of the dose rate[8]. The purpose of the ICRU report is to provide reference data derived from measurements against which the results of routine methods of assessing annual doses using calculations can be compared (benchmarked) for validation purposes.The cut-off rigidity is not a standard input parameter for flight codes as are position and altitude. There are many points with identical vertical cut-off but different non-vertical cut-offs and hence different dose rates. Comparison of the results for locations with a certain vertical cut-off can be used as a test of the code, but it does not consider the local dose rates which shall be integrated for a flight dose.Therefore, using ICRU 84 cannot be the only test of a code.
The agreement between dose values calculated using a code and the comparison data should be as good as possible taking into account the uncertainties of the measurements. The dependence of re is to be determined on the basis of different routes over a large range of the magnetic latitude Bm (from the equator to the polar regions), which allows the code validation to be formulated based on either of the following criteria.
In order to check the correctness and reliability of the validated code in routine use, regular comparison flights on representative routes should be used to allow dose values obtained by measurements to be directly compared with the values determined by the code. The measurement procedure shall be in accordance with ISO 20785-3.BS ISO 20785-4 pdf free download.