Chronic radiation doses - hdbk1130cn20075

DOE-HDBK-1130-98

Module 2 Biological Effects

Instructor's Notes

Ionizing radiation is used to treat cancer

in these patients because cancer cells

are rapidly dividing and therefore

sensitive to ionizing radiation. Some of

the side effects of people undergoing

radiation therapy are hair loss, nausea,

and tiredness.

Probability of a large acute dose

What is important to understand is that it takes a

large acute dose of radiation before any physical

effect is seen. These acute doses have

occurred in Hiroshima/Nagasaki, and in a few

radiation accidents, including Chernobyl. The

possibility of a radiological worker receiving a

large acute dose of ionizing radiation on the job is

extremely low. Typically, radioactive materials

are handled in small quantities that do not

produce a large amount of radiation. Where

there is a potential for larger exposures, many

safety features are required.

Chronic radiation doses

A chronic radiation dose is typically a small amount

EO5 Define the terms "acute

of radiation received over a long period of time. An

dose" and "chronic dose."

example of a chronic dose is the dose we receive

EO6 State examples of

from natural background every day of our lives. The

chronic radiation dose.

body's cell repair mechanisms are better able to

repair a chronic dose than an acute dose.

The body has time to repair damage because a

smaller percentage of the cells need repair at

any given time.

The body also has time to replace dead or non-

functioning cells with new, healthy cells.