What is the dose limit for radiation exposure to the general public per year?

The correct dose limit for radiation exposure to the general public per year is 0.5 rem. This limit is established to protect individuals who are not occupationally exposed to radiation as part of their job. The rationale behind this limit is to minimize the risk of harmful effects from radiation exposure, which can include an increased chance of cancer and other health issues over time.

Regulatory bodies, such as the Environmental Protection Agency (EPA) and the National Council on Radiation Protection and Measurements (NCRP), emphasize the importance of keeping radiation exposure as low as reasonably achievable (ALARA) for the general public. Setting the limit at 0.5 rem acknowledges the need for protection while also considering the potential for natural background radiation and occasional medical exposures that a person may encounter. The threshold aims to balance safety with the realities of environmental and medical exposure scenarios.

In comparison, the other options reflect higher limits that are not applicable to the general public but might relate to specific occupational exposures or controlled environments, where individuals may have additional safety measures in place. These figures serve a different purpose and are not considered appropriate for the general population, who should have the lowest possible exposure risk.