University of Virginia
Physics Department

Personal Exposure to Radiation

A Physical Science Activity

Student Activity




  1. List 3 sources of radiation that you think have the most potential danger.
  2. Fill in the activity sheet.
  3. Compare sources of radiation that you thought were most dangerous to the chart of radiation exposure doses. How does nuclear energy risk compare to other forms of exposure?


Activity Sheet


Average Personal Radiation Dose

Every day each of us is exposed to radiation: ultraviolet light from the sun, x-rays, warmth from other people, and a vast spectrum of electromagnetic waves. Some of these are very high energy and potentially dangerous. Exposure to these should be limited. Some radiation exposure is unavoidable, such as the cosmic radiation from space. Some radiation is permitted for medical or health benefits.

Use the information below to calculate your exposure to radiation for the past calendar year. This is only an estimated value.

Type of Radiation

Amount of Radiation in mrem

From Space


Cosmic radiation at sea level - 26


For your elevation (in feet) add:


1000 feet add 2


2000 feet add 5


3000 feet add 9


4000 feet add 15


From the Ground


(for the Atlantic Gulf Coastal Plain)


From Food, Water and Air


From Building Materials


If you live in a wooden structure -5


If you live in a brick structure -7


From Jet Plane Travel


For each 2500 miles add 1


From Nuclear Fuel Plants


Average dose is .1 mrem if there are one or more plants in your state.


Virginia has two nuclear plants.


From Radioactive Waste Disposal


Average US dose is 1.0


From Medical Diagnosis


x-rays: chest - 6


pelvis and hips - 65


arms, hands, legs, feet - 1


skull, head, neck - 20


mammogram - 400


From Cigarette Smoke


If you are exposed to cigarette smoke on a regular basis add 100-500


(Add 500 if you are exposed every day for 8 hours or more)


If you smoke one pack of cigarettes or more a day add 1500