Control zones will be established for controlling movement of radiation sources and personnel. These zones will protect personnel and property from accidental contamination and unnecessary radiation exposure. Every individual working or visiting such areas should observe signs and directions indicating actions to be taken in a specified area.
The control zones are designated as follows:
- A restricted area is an area where access is controlled for purposes of personnel protection. State and federal regulations place the following restrictions on elevated radiation areas:
- Radiation Area: A radiation area is defined as any area, accessible to personnel, in which radiation levels could result in an individual receiving a dose equivalent in excess of 5 millirems at a distance of 30 cm in one hour from a radiation source. These areas must be posted.
- High Radiation Area: This area is defined as any area, accessible to personnel when radiation levels could result in individuals receiving a dose equivalent in excess of 100 millirems in one hour at 30 cm from the radiation source or boundary. High Radiation Areas require access control measures to be instituted as prescribed in l0 CFR20.l60l.
- Contamination Zone--an area where controlled access is maintained for the purpose of contamination control. Persons should not enter such a zone without authorization and proper personnel protection. The following defines a contaminated zone in restricted areas:
Removable Contamination
| Type of Radiation | Limits (dpm/100 cm2) |
|---|---|
| Beta(except tritium) | 500 |
| Tritium | 1000 |
| Alpha | 50 |