At what radiation level should the perimeter of the cold zone be established?

The correct choice for establishing the perimeter of the cold zone in relation to radiation levels is based on safety protocols for first responders and the public. A perimeter set at 1.0 m/R is a precautionary distance that allows for a sufficient buffer zone where radiation levels are considered safe for personnel not equipped for direct radiation exposure.

This specific distance is balanced to ensure that the risk from radiation is effectively minimized, reducing the potential for harmful exposure while still allowing for effective management of the incident. It reflects the guidelines developed through established safety criteria in hazardous environments, specifically those dealing with radiological materials.

Higher radiation levels would necessitate a larger perimeter, while lower levels might allow for a smaller designated zone. The choice of 1.0 m/R is thus an essential standard for maintaining safety during operations involving radiation, ensuring that personnel can work effectively without the added risk of radiation exposure.