BS EN ISO 20785-2:2020 pdf free.Dosimetry for exposures to cosmic radiation in civilian aircraft. Characterization of instrument response.
BS EN ISO 20785-2 This document specifies methods and procedures for characterizing the responses of devices used for the determination of ambient dose equivalent for the evaluation of exposure to cosmic radiation in civilian aircraft. The methods and procedures are intended to be understood as minimum requirements.The following five documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO/IEC Guide 98-1, Uncertainty of measurement一Part 1: Introduction to the expression of uncertainty in measurement
ISO/IEC Guide 98-3, Uncertainty of measurement一Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) operation that, under specified conditions, establishes a relation between the conventional quantity,Ho, and the indication, G .Note 1 to entry: A calibration can be expressed by a statement, calibration function, calibration diagram,calibration curve or calibration table. In some cases, it can consist of an additive or multiplicative correction of the indication with associated measurement uncertainty.Note 2 to entry: It is important not to confuse calibration with adjustment of a measuring system, often mistakenly called “self-calibration’ ‘，or with verification of calibration.The primary galactic cosmic radiation (and energetic solar particles) interact with the atomic nuclei of atmospheric constituents, producing a cascade of interactions and secondary reaction products that contribute to cosmic radiation exposures that decrease in intensity with depth in the atmosphere from aviation altitudes to sea level[15][16]. Galactic cosmic radiation [GCR) can have energies up to 1020 eV, but lower-energy particles are the most frequent. After the GCR penetrates the magnetic field of the solar system, the peak of its energy distribution is at a few hundred MeV to 1 GeV per nucleon, depending on solar magnetic activity, and the spectrum follows a power function of the form E-2,7 eV up to 1015 eV;above that energy, the spectrum steepens to E-3. The fluence rate of GCR entering the solar system is fairly constant with time, and these energetic ions approach the Earth isotropically.The magnetic fields of the Earth and sun alter the relative number of GCR protons and heavier ions
reaching the atmosphere. The GCR ion composition on the fluence basis for low geomagnetic cut-off and low solar activity is approximately 90 % protons, 9 % He ions and 1 % heavier ions; at a vertical cut-off of 15 GV, the composition is approximately 83 % protons, 15 % He ions and nearly 2 % heavier
ions[1Z][18].BS EN ISO 20785-2 pdf download.