Introduction - DOE-HDBK-1141-2001

Radiological Assessor Training

DOE-HDBK-1141-2001

Instructor's Guide

Show OT 6.1 and OT 6.2.

Introduction

State objectives.

The guidance in DOE-STD-1136-2000, Guide of

Good Practices for Occupational Radiological

Show OT 6.3.

Protection in Uranium Facilities, should be reviewed

in detail prior to conducting an assessment of

uranium facilities. The following is a brief overview

of the radiological aspects of uranium.

II.

Radiological aspects of uranium

Obj. 1

Identify the radiological properties

A. Radiological properties of uranium

of uranium.

Fifteen radioisotopes exist, but the three of most

Review DOE-STD-1136-2000,

Guide of Good Practices for

concern to the uranium industry are:

Occupational Radiological

Protection in Uranium Facilities

Uranium-238:

99.7% abundant in natural uranium;

half-life = 4.5 billion yrs,

specific activity = 3.3 E-7 Ci/g

Uranium-235:

0.72% abundant;

half-life = 710 million yrs,

specific activity = 2.1 E-6 Ci/g

Uranium-234:

0.006% abundant;

half-life = 247 thousand yrs,

specific activity = 6.2 E-3 Ci/g

Enriched uranium has a higher content of

Uranium-235 than found in nature. Typical

enrichment values are:

2%-3% Uranium-235: power reactor grade

fuel

>90% Uranium-235: weapons grade material

Module 6 3