Because the radiation levels in the area where you will be working are required by law to be kept quite low, there is not considered to be significant health risk to individual adult employees. The dose from natural radiation is higher in some states, such as Colorado, Wyoming, and South Dakota, primarily because of cosmic radiation. In these states the average person gets 1,000 mrem every eight years. Natural background radiation levels are also much higher in certain local areas. A dose of 1,000 mrem may be received in some areas on the beach at Quarapari, Brazil, in only about nine days, and some people in Kerala, India, get a dose of 1,000 mrem every five months.
Many people receive additional radiation for medical reasons.
The annual radiation dose averaged over the U.S. population from diagnostic X-rays is 40 mrem per year. The possible annual dose from working eight hours a day near a granite wall at the Redcap Stand in Grand Central Station, New York City, is 200 mrem, and the average annual dose in the United States from TV, consumer products, and air travel is 2.6 mrem. Radiation, like many things, can be harmful. Control of exposure to radiation is based on the assumption that any exposure, no matter how small, involves some risk. The occupational exposure limits are set so low, however, that medical evidence gathered over the past 50 years indicates no clinically observable injuries to individuals due to radiation exposures when the established radiation limits are not exceeded.