Module Outline - hdbk1130cn20068

DOE-HDBK-1130-98

Module 2 Biological Effects

Instructor's Notes

The fourth and largest group of individuals are patients

who have undergone radiation therapy for cancer and

other diseases.

MODULE OUTLINE

Introduce objectives

II.

A. Sources of Radiation

We live in a radioactive world and always have. In fact,

the majority of us will be exposed to more ionizing

radiation from natural background radiation than from our

jobs.

Natural sources

There are several sources of radiation that occur

EO1 Identify the major

naturally. The radiation emitted from these sources

sources of natural background

is identical to the radiation that results from

and manmade radiation.

manmade sources.

The four major sources of naturally occurring

radiation exposures are:

Cosmic radiation

Sources in the earth's crust, also referred to as

terrestrial radiation

Sources in the human body, also referred to as

internal sources

Radon

Cosmic radiation (total average dose ~

28 mrem/yr)

Cosmic radiation comes from the sun and

outer space. It consists of positively

charged particles and gamma radiation.

At sea level, the average annual cosmic

radiation dose is about 26 mrem.

At higher elevations, the amount of

atmosphere shielding cosmic rays

decreases; therefore, the dose increases.