|As far as the aircrew exposure issue is concerned, a deep change appeared in the committee’s approach compared to its publication 60, i.e. “exposure to cosmic rays at altitudes above ground level may be considered as a candidate for either exclusion from legislation or generic exemption from most regulatory requirements, depending on the legislative system and national arrangements in place”.
This approach is not correct for the following reasons:
- The effective dose received by aircraft crews is between 1 and 6 mSv per year for long haul flights. It is clearly above the dose limit for the general public and comparable or even higher than doses received by the great majority of nuclear workers. So, why, for categories exposed to the same or an higher magnitude of risk, is there different ways to manage this risk? Further, can we accept to definitively say that this source of human exposure is “unamenable to control by any reasonable means” whereas the means of assessing the individual doses exist?
- For the most exposed crew members (routes at high latitude), the dose can be used to manage the activity.
- There is the situation of the pregnant women even if specific dispositions may already be taken for aircraft crew members.
- A lot of civil aviation companies (especially in Europe) have already taken dispositions to evaluate and record the individual doses aboard aircraft. So, we may fear that a change in the rules in an opposite way will cause a negative perception of radiation protection management in general.
- More than 50% of exposed persons are women in reproductive age and the radiation protection aspect will be correctly taken into account only in case of an appropriate survey.
- More than 50 % of the effective dose is received from radiation with high LET. This is unique among the professional exposure and leads to keep a specific dose assessment.
- The case of a heavy GLE should be named, even if the probability of such an event is very low, that aircraft crews may be exposed in the order of mSv during a single flight.
In conclusion, while it is justified to exclude doses from cosmic radiation at ground level from the scope of radiation protection regulations, the exemption of human activities such as civil aviation which result in increased doses to a large global workforce is unacceptable.