As discussed elsewhere in this chapter, the law im­poses radiation dose limits on several categories of person, but principally persons at work are ‘allowed’ to receive 50 mSv per year. However, if they are non-classified workers this drops to 15 mSv per year. Members of the public may receive 5 mSv per year.

The dose to the general public from radiation ori­ginating from the power station is controlled by the positioning of the site boundary fence. The radiation dose to non-classified persons on a licensed site (e. g., administration staff, canteen staff, etc.) are limited by the positioning of the controlled area. The controlled area boundary encompasses the reactor building, al­though with the provision of additional facilities, for instance a laundry building, it may be necessary to have other parts of a site contained within a controlled area fence. Access to the controlled area on a day — to-day basis is restricted to classified personnel and is made via a guardians post. All classified staff must wear a whole-body film badge whilst in the controlled area. All other personnel (e. g., visitors and contractors) are only allowed into the controlled area under specified procedures.

Section 4,3 of this chapter on the Radiological Safety Rules, describes how a nuclear site is zoned in terms of both radiation and contamination levels and how access to the various zones is controlled. This ensures that under normal working conditions that annual dose limits, or any other imposed level, cannot be exceeded.