Each of us is exposed to radiation from radioactive materials that exist in nature, including the sun and earth. Small traces of radiation are even present in food and water. Radiation is also released from man-made sources such as x-ray machines, television sets and microwave ovens. Nuclear power plants use the heat generated from nuclear fission in a contained environment to convert water to steam, which powers generators to produce electricity.
Atoms are the building blocks of all material. If an atom is unstable – meaning it contains excess energy – it emits radiation.
Millions of packages of radioactive materials are transported in the United States annually. Most shipments consist of medical and industrial products. Other shipments include nuclear power plant fuel, nuclear weapons and weapons material, and radioactive waste generated by hospital, laboratories, nuclear reactors, and military facilities.
In general, radiation has a cumulative effect. The longer a person is exposed to radiation, the greater the risk. A high exposure to radiation can cause serious illness or death. Studies show that any negative health effects that might be caused by low-level exposure to radiation cannot be distinguished from those caused by other environmental hazards.
Radioactive material deposited in undesired locations is called radioactive contamination. The difference between contamination and radiation is important to understand. You can be exposed to radiation without becoming contaminated. When you are exposed to radiation, the radiation does it's damage, expends all it's energy, and is gone. If you carry contamination on your clothes or body, the material continues to emit radiation as long as it is radioactive.
In general there are three ways to minimize radiation exposure to your body: distance, shielding and time.
- Distance: The more distance between you and the source of the radiation, the better. In a serious radioactive material accident, local authorities will call for an evacuation – to increase the distance between you and the radiation.
- Shielding: Like distance, the more heavy, dense material between you and the source of the radiation, the better. This is why local authorities could advise you to remain indoors if an accident occurs at a nearby power plant.
- Time: Most radioactivity loses it's strength fairly quickly. In a power plant accident, local authorities will monitor any release of radiation and determine when the threat has passed.
Know the terms used to describe a nuclear emergency:
- Notification of unusual event means a small problem has occurred at the plant. No radiation leak is expected. Federal, state and county officials will be told right away. No action on your part will be necessary.
- Alert means a small problem has occurred, and small amounts of radiation could leak inside the plant. This will not affect you. Federal, state and county officials will stand by. You should not have to do anything.
- A site area emergency is a more serious problem. Small amounts of radiation could leak from the plant. If necessary, state and county officials will act to assure public safety. Area sirens may be sounded. Listen to your radio or television for safety information.
- A general emergency is the most serious problem. Radiation could leak outside the plant and off the plant site. The sirens will sound. Tune to your local radio or television station for reports. State and county officials will act to assure public safety. Be prepared to follow their instructions promptly.
If you have been outdoors during a radiological leak, take a thorough shower. Change your clothes and shoes. Put the items you were wearing in a plastic bag. Seal the bag and store it out of the way. Put food in covered containers or in the refrigerator. Food not previously in covered containers should be washed first.
If an accident involving radioactive material were to release radiation in your area, the City of Ann Arbor’s Siren Warning System would be activated. In the event that the sirens are activated due to a Radiological Emergency you will hear a three-minute steady tone - TAKE COVER IMMEDIATELY!!! Tune your battery-operated radio to WAAM 1600 AM, WEMU 89.1 FM, or KOOL 107.1 FM for more information.