Search results
Results From The WOW.Com Content Network
Airline crews flying long-distance high-altitude routes can be exposed to 2.2 mSv of extra radiation each year due to cosmic rays, nearly doubling their total exposure to ionizing radiation. Average annual radiation exposure ( millisieverts )
There are three fundamental ways to reduce exposure to ionizing radiation: [32] increasing the distance from the radiation source; reducing the exposure time; shielding (i.e.: a physical barrier) Shielding is a plausible option, but due to current launch mass restrictions, it is prohibitively costly.
Orion's orientation during flight affected radiation exposure, which dropped by half when the spacecraft made a 90-degree turn flying past the inner Van Allen belt.
Flying 12 km (39,000 ft) high, passengers and crews of jet airliners are exposed to at least 10 times the cosmic ray dose that people at sea level receive. Every few years, a geomagnetic storm permits a solar particle event to penetrate down to jetliner altitudes. Aircraft flying polar routes near the geomagnetic poles are at particular risk.
Radiation has also recently been linked to a higher incidence of cataracts in astronauts. Outside the protection of low Earth orbit, galactic cosmic rays present further challenges to human spaceflight, [45] as the health threat from cosmic rays significantly increases the chances of cancer over a decade or more of exposure. [46]
Animal behavior studies indicate that high-HZE radiation has a high RBE, but the data are not consistent. Other uncertainties include: age at exposure, radiation quality, and dose-rate effects, as well as issues regarding genetic susceptibility to CNS risk from space radiation exposure. More research is required before CNS risk can be estimated.
Flight-time equivalent dose (FED) is an informal unit of measurement of ionizing radiation exposure. Expressed in units of flight-time (i.e., flight-seconds, flight-minutes, flight-hours), one unit of flight-time is approximately equivalent to the radiological dose received during the same unit of time spent in an airliner at cruising altitude.
EPCARD allows calculation of a simulated dose from most important components of penetrating cosmic radiation on any aviation route and for any flight profile at altitudes from 5 to 25 km. EPCARD helps airlines monitor radiation exposure, and comply with regulations relating to this area.