EC Article 42, Council Directive 96/29/ Euratom of 13 May 1996, states:
Each member state shall make arrangements for undertakings operating aircraft to take account of exposure to cosmic radiation of aircrew who are liable to be subject to exposure of more than 1 millisievert (mSv) per year.*
The undertakings shall take appropriate measures, in particular:
a. to assess the exposure of the crew concerned;
b. to take into account the assessed exposure when organising working schedules with a view to reducing the doses of highly exposed aircrew;
c. to inform the workers concerned of the health risks their work involves;
d. to apply Article 10 of the Directive to female aircrew. (Article 10 calls for special protection during pregnancy and breastfeeding. As soon as a pregnant woman informs her employer that she is expecting a child, her working conditions shall "therefore be such that the equivalent dose to the child to be born will be as low as reasonably achievable and that it will be unlikely that this dose will exceed 1mSv during at least the rest of the pregnancy".)
*According to the UK's National Radiological Protection Board, aircrew receive an average radiation dose of 4.6mSv a year - compared to 3.6mSv received by nuclear workers.
Source: Flight International