title: Overview on experience to date on human exposure to space radiations.
abstract: The human exposure in space depends on the three factors: the flight trajectory, its date and duration and the cyclogram of the cosmonaut's activities. In the near-Earth orbits the daily dose varies within the limits of (1.5-5.0) 10(-4) Gy day-1 and greatly increases if the altitude increases. The mean daily quality factor is 1.6-2.0. Strong solar proton events in the orbits with the inclination of < 52 degrees result in the dose rate increase up to 2-3 cGy day-1.  On the surface of the orbital spacecrafts the daily dose reaches 2 Gy. The neutron dose depends on the shielding mass distribution varying within the limits of 6%-30% of the charged particles dose. In deep space the dose is mainly formed by the galactic and solar cosmic rays(GCR,SCR). Behind the shielding of 2-3 g cm-2 Al the GCR dose varies in the range of (20-30) 10(-5) Gy day-1. The SCR dose can reach hundreds of cSv.
authors.affiliation: Institute of Biomedical Problems, Moscow, Russia.
authors.forename: V M
authors.initials: VM
authors.lastname: Petrov
mesh_terms: D003359:Cosmic Radiation; D004583:Electrons; D006801:Humans; D018499:Linear Energy Transfer; D008452:Maximum Allowable Concentration; D019047:Phantoms, Imaging; D011522:Protons; D011829:Radiation Dosage; D011835:Radiation Protection; D012062:Relative Biological Effectiveness; D019445:Solar Activity; D013026:Space Flight / Q000592:standards*; D018531:Spacecraft / Q000592:standards; D013819:Thermoluminescent Dosimetry
chemical_list: D011522:Protons