Question

Describe the difference between exposure and contamination and why this distinction is important. Give an example to illustrate your description.

Answer 1

Exposure vs. Contamination

Exposure – Radiation waves or particles penetrate the body. If someone is exposed to external radiation:

 Do not become radioactive

 Pose no hazard to nearby individuals

 Do not become contaminated

Contamination – Unwanted radioactive material in or on the body, or spread about the environment (radioactive material in unwanted places). If someone is externally contaminated, they can spread contamination:

 About 80% can be removed by taking of clothing

 Most remaining contamination can be removed by gently washing skin and hair

Internal Contamination – Can result from inhalation, ingestion, absorption, puncture or open wound. Internally contaminated persons present a minimal risk to responders, but are usually externally contaminated as well.

A person exposed to radiation is not necessarily contaminated with radioactive material. For a person to be contaminated, radioactive material must be on or inside of his or her body.

For example, when an individual has a chest x-ray, he or she is exposed to radiation. To prevent occupational harm, the radiology technician is protected through distance and shielding. To prevent harm to the patient, the duration of exposure is carefully controlled. People do not become radioactive after exposure to common radioactive sources. After a chest x-ray, a person is not contaminated and does not pose a risk to others.