The government plans to ask Japanese airlines to take steps to protect their cockpit and cabin crews from exposure to cosmic radiation during high-altitude flight, it was learned Thursday.
The Education, Culture, Sports, Science and Technology Ministry will ask the airlines to introduce voluntary standards that will limit air crews' exposure to radiation to about 5 millisieverts a year, ministry officials said.
To achieve the objective, the ministry will soon draft guidelines that will require airlines to measure crews' exposure to radiation from their flight times and routes in order to reflect such data in their work records.
The ministry says 5 millisieverts of radiation equals the amount of radiation one would get after 1,000 hours of flying a year. Typically, air crews are exposed to 3 to 4 millisieverts a year, it said.
"This is not a level of radiation that requires immediate medical attention," a ministry official said.
The high-altitude environment has more cosmic radiation than the environment at ground level, experts say.
The International Commission on Radiological Protection issued two advisories, in 1990 and in 1997, asking authorities to treat air crews' radiation exposure as something inherent in their work.
The Airline Pilots Association of Japan and various cabin crew unions have asked for protective measures.