Background radiation averages

Acute radiation damage

Annual adult worker radiation limits

Annual minor worker radiation limits

Nonoccupational annual radiation dose limits
Also, the dose to an individual in any unrestricted area from external sources shall not exceed 0.002 rem (2 mrem) in any one hour.

The Nuclear Regulatory Commission (NRC) and the Minnesota Department of Health (MDH) both require individuals who use sources of ionizing radiation be monitored for radiation exposure if their potential for exposure from external and/or internal radiation sources exceed certain levels. These levels are currently 10% of the annual occupational dose limits.

Appropriate shielding must be provided so that the exposure rate from radiation sources is less than 2.5 mR/hr. at 12 inches in any controlled area and less than 0.25 mR/hr. in any uncontrolled area.

gamma_attenuation.xlsx