ML20215M877

Rev 2 to Training Lesson Plan GE-LP-001, Radiation Protection - Fundamentals

ML20215M877
Person / Time
Site:	Vogtle
Issue date:	03/06/1986
From:	Green L GEORGIA POWER CO.
To:
Shared Package
ML20215M870	List: ML20215M869 ML20215M874 ML20215M877 ML20215M881 ML20215M887 ML20215M890 ML20215M892
References
GE-LP-001, GE-LP-1, NUDOCS 8611030400
Download: ML20215M877 (16)

Text

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VOGTLE ELECTRIC GENERATING PLANT g2 TRAINING LESSON PLAN TITLE: RADIATION PROTECTION - FUNDAMENTALS GE-LP-001 NUMBER:

PROGRAM: GET (BADGE TRAINING) GE-001 REVISION: 2 AUTHOR: LEATRICE G. GREEN DATE: 3/6/86 APPROVED: W (h, DATE: 2 /c/gf.,

INSTRUCTORGUIDElNNES:

I. LESSON PRESENTATION - 1 HOUR, 40 MINUTE LECTURE INCLUDING REVIEW FOLLOWED BY A 10 MINUTE FORMATIVE TEST.

II. MATERIALS REQUIRED:

A. SLIDES, TRANSPARENCIES B. FRISKER C. ALPHA, BETA, GAMMA SOURCES D. SHIELDING MATERIALS (PAPER, PLASTIC, PLYWOOD, Al, Pb)

E. CONSUMER PRODUCTS AS RADIATION SOURCES (LANTERN MANTLE, ETC.)

F. SLIDE PROJECTOR G. OVERHEAD PROJECTOR H. DOSIMETRY (TLD, POCKET DOSIMETER)

I. HANDOUTS J. VCR AND VIDEOTAPE: " RADIATION NATURALLY" i

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1. PURPOSE STATEMENT:

THIS LESSON WILL INTRODUCE THE TRAINEE TO THE RADIOLOGICAL HAZARDS THAT EXIST IN NUCLEAR POWER PLANTS AND WILL PROVIDE HIM WITH A KNOWLEDGE WHICH WILL FACILITATE FURTHER STUDY OF RADIOLOGICAL PROTECTION TOPICS.

II. LIST OF. OBJECTIVES:

This lesson is designed to enable tht trainee to:

1. Identify the following:

a. Atoms

b. Elements

c. Protons

d. Electrons

e. Neutrons

2. Distinguish between Radioactivity and Radiation. Identify the type of radiation that can cause materials to become radioactive.

3. State the relationship between radioactive contamination and radiation.

4. Identify correct statements pertaining to each of the four types of ionizing radiation (Alpha, Beta, Gamma, Neutron) to include:

a. Source (where the types of radiation occur in the plant)

b. Biological hazard (how and where they most often cause damage to the body)

c. Required means of detection

d. Shielding (hcw they can be stopped)

e. Possibility of exposure (how likely you are to be exposed to them)

5. Identify the purpose for which each of the following instruments is used:

a. Frisker

b. TLD

c. Pocket Dosimeter

6. Identify the units used to measure Radioactivity and Radiation.

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7. Convert any given number of rem to millirem or any number of millirem to rem.

8. Identify the average yearly dose range of background radiation received by the general public in the United States.

9. Given several radiation sources, identify those which are scurces of background radiation and classify each source identified as either natural or man-made.

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10. Given several sources of radiation, select the one which is the greatest source of radiation exposure to the average person irt the United States.

11. Given a description of a work environment, identify the types of radiation which a worker might be exposed to in that environment.

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CLTP 001

. REF5RENCES:

1. 10CFR19 and 10CFR20

2. USNRC REG. GUIDES 8.13, 8.27, 8.29

3. VEGP - 40000 SERIES PROCEDURES

4. " HEALTH PHYSICS FUNDAMENTALS"- GENERAL PHYSICS CORPORATION

5. " RADIATION PROTECTION"- GENERAL PHYSICS CORPORATION

6. " FUNDAMENTALS OF PHYSICAL SCIENCE"- GENERAL PHYSICS CORPORATION

7. " BASIC RADI0 CHEMISTRY"- J.F. ALLEN AND A.K. B0yNETTE

8. " INTRODUCTORY HEALTH PHYSICS COURSE"- HOUSTON HOU6 TON LIGHTING AND PdWER CO.

9. " RADIATION RISKS FOR NUCLEAR WORKERS"- ATOMIC INDUSTRIAL FORUM

10. " BASIC RADIATION PROTECTION SLIDE SERIES"- NUCLEAR SUPPORT SERVICES, INC.

11. " RADIATION SAFETY TECHNICIAN TRAINING COURSE"- H. J. MOE 3

r GE-LP-001 Ill. LESSON OUTLINE: NOTES A. INTRODUCTION ,

Although many jobs have health risks associated with them, most of those risks are readily apparent. The hazard of radiation is more subtle. A person may be exposed to signi-ficant levels of radiation without knowing it since human senses cannot detect ionizing radiation. Federal regulations require that individuals working in the nuclear industry be given instruction in radiation protection in an effort to insure that .ccupational radiation exposures are kept as low as is reasonably achievable. This lesson and the following eight are designed to fulfill this requirement.

Importance of the B. OVERVIEW OF A PWR gross structure and functions of the The most common method of supplying mechanical power to rotate major plant generator shafts in power plants is by Steam Turbines. The components are as difference between one power plant and another is how steam is follows:

produced. Whatever method is used, it must supply heat in 1) Primary large quantities to generate the steam required to drive steam containment is turbines. In nuclear power plants, heat results from nuclear designed to prevent fission in the uranium fuel. The heat generated in the accidental release of nuclear fuel is transferred to a fluid called the reactor radioactive material coolant that flows pass the fuel., to the environment.

2) The reactor VEGP is a PWR facility. It uses H O as the Rx coolant; the coolant water and the 2

' reactor coolant is kept at high pressure and it does not boil biological shield appreciably. The reactor coolant heats up as it flows pass serve to protect the nuclear fuel and it is then pumped to large heat exchangers, personnel from steam generators, where it gives up this heat to a completely radiation originating separate system also containing H 0. This H O is at a lower in the reactor core 2 2 pressure than the reactor coolant. It boils when heated and while the reactor is is thereby converted to steam for use in the turbine. operating.

3) The reactor The steam expands through a turbine causing the turbine and coolant is circulated generator shaft to rotate. The steam is condensed and throughout the returned to the place where it was generated, the steam primary system to generator. produce steam in the secondary system.

C. BASIC STRUCTURE OF MATTER Prior to understanding radiation and radioactive material, you should understand some basic concepts of matter because radiation and radioactive material are matter.

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GE-LP-001 Ill. LESSON OUTLINE: NOTES

1. Basic Structure of Matcer

a. Matter is a term used to describe all substances or material. Example:

b. Matter is defined as anything that occupies space H O (liquid) 2 and has weight. ice (solid)

c. Matter exists in one of three physical states: steam (gas)

Physical changes in

1. Solid no way changed the

11. Liquid chemical nature of 111. Gas matter. Chemical nature of a substance In addition to physical changes, atoms and molecules is a function of its undergo chemical reactions. This is an important concept atomic structure.

to grasp because radioactive material remains radioactive H 0, ice, and steam 7

regardless of any physical or chemical changes it may are all composed of undergo. the same atoms, 2 hydrogen atoms and 1 Radioactive hydrogen remains radioactive if the water oxygen atoms. H 0.

2 which contains the hydrogen is converted to either steam or ice. The hydrogen would also remain radioactive even when water which contains the radioactive hydrogen undergoes a chemical reaction to produce hydrogen gas.

2. Nature of the Atom

a. Atoms Inside every atom are 2 forces:

Atoms are the building blocks of which elements are 1) Electrostatic-like made. Each element is made of its own unique type charges repel each of atom. This is what makes one element different other p-p, tend to from another. push the n-n nucleus of an atom

b. Elements apart.

2) Binding Energy -

Chemical substance that cannot be divided into a Counter acts the simpler substance by chemitsi means. All matter is electrostatic, composed of one or more elements. More than 100 holds the protons elements are known to exist, most of which occur in & neutrons together nature. However, a few are man-made or " synthetic" in the nucleus, elements. p-p, n-n, n-p

c. Atomic Structure Any atom consists of two parts - the nucleus and The balance of these electron orbitals which surround the nucleus. Three two forces determine types of particles are found in these two parts of if the atom is stable the atom. They are: or unstable (radio-active).

i. Protons - positively charged particles located in the nucleus. (+)

3 11. Neutrons - electrically neutral particles

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located in the nucleus. ()

iii. Electrons - negatively charged particles located in the electron orbitals (-)

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GE-LP-001 111. LESSON OUTLINE:' NOTES

d. Isotopes:,

i. When atoms of an element have the same number of protons in the nucleus but differ in the number of t.autrous they are said to be isotopes of that element.

ii. The number of protons (referred to as the atomic number) will remain the same for the isotopes of the same element, however, the total number of, protons and neutrons (referred to as the mass number) will be different.

Example:

Element Protons Neutrons Oxygen 8 8 8 9 8 10

3. Radiation Some atoms have unstable nuclei. These nuclei spontaneously undergo change,s in order to achieve a more stable condition. In so doing, they emit particles, and energy. These emissions are called radiation.

The substances which emit such radiation are said to be radioactive.

a. Definitions

1. Radioactivity - the spontaneous disintegration or decay of radioactive nuclei with the accompanying emission of radiation.

11. Radiation - the particles and energy released during radioactive decay.

137 iii. Half-life (t ) - the time required for half of Cs -t = 0 yrs 60 the radioactive atoms in a sample to decay. Co -t = 5.27 yrs iv. Radioactive Contamination - Radioactive material anywhere it is not wanted.

The instructor should emphasize that radiation and ccntamination are not the same. Note practical difference between the two.

b. Ionizing Radiation - Many types of radiation exist but the types which we are concerned are called ionizing radiation because of their capacity to form cicetrically charged particles or ions as they pass through matter. When these charged particles are produced in living cells, the cell chemistry 9

is altered, resulting in abnormal cell growth or cell destruction.

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GE-LP-001

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lli. LESSON OUTLINE: NOTES Ion - Atog or molecule that has lost or gained electrons.

c. Types of Ionizing Radiation ACTIVITY: Trainees will complete chart (handout) as each type of radiation is discussed.

i. Alpha - slow moving positively charged particles with little penetrating power.

a) Sources - Uranium fuel (New and old fuel during receiving and/or refueling operations) b) Biological hazard - internal The alpha radiation source must be inside the body to do damage.

c) Means of detection - instruments Details later in d) Shielding requirements - thin sheet of lesson.

paper, clothing, top dead layers of skin, etc.

e) Importance _s exposure source - minor (exposure maprobable).

ii. Beta - relatively fast moving negatively charged particles with moderate penetrating power.

a) Sources - radioactive waste, contaminated tools and equipment, most open fluid transfer system in the plant.

b) Biological hazard - primarily external to skin and eyes. It does not penetrate deeply enough to.cause damage to internal organs.

Explair. that an "eiternal" hazard is also an internal hazard.

c) Means of detection - instruments.

d) Shielding requirements - plastic, aluminum, plywood. '

e) Importance as exposure source - major.

iii. Gamma - Highly penetrating electromagnetic radiation.

Mention X-Radiation as being similar to gamma. Note, however, that x-rays originate in the electron orbi-tals, not in the nucleus as do gamma rays.

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GE-LP-001 ill. LESSON OUTLINE: NOTES a) _ , Sources - radioactive waste, contaminated tools and equipment, most fluid transfer systems in plant.

b) Biological hazard - external to all body tissues.

c) Means of detection - instruments.

d) Shie1 ding requirements - lead, steel, concrete.

e) Importance as exposure source - major.

iv. Neutron - highly penetrating electrically neutral particles, a) Sources - operating reactor (fission During shutdown most process). of the neutrons are b) Biological hazard - external to all absorbed by control body tissues. rods which are c) Means of detection - instruments. located in the d) Shielding requirements - water, hydro- reactor vessel with genous materials /(e.g. paraffin). the fuel rods.

e) Importance as exposure source - minor Production of (exposure improbable). neutrons from the fission process has

v. Neutron Activation - Neutron radiation can been stopped when cause certain non-radioactive atoms to become the reactor is shut-radioactive. This process is called " neutron down.

activation". For example:

Sources of neutrons 59 ON 60 in the Co Co RADIATION a. Primary Stable Radioactive

1) Pu-Be (OPTIONAL) P u--- Pu +

DEMONSTRATION: Show slides that illustrate relative penetrating power and ranges in air of alpha, beta, t = 94 yrs gamma radiation. Use , , sources and detector g g to demonstrate effectiveness of various shielding 9Be + 4 d materials. Points of interest that can be used t 4 2 6' +0" 1

enhance demonstration are as follows: 2) 25295 1+FF2 + 0"

1. After showing the class the Polonium 210 alpha FF (Spontaneous source, point out: a) it is naturally occurring Factor) in earth; b) it grows into our food chain; c) the average cigarette smoker receives several Stellite REM of expumure to his lungs every year from the alpha decay of Polonium 210. b. Secondary

2. After showing the beta source, point out: a) a hand laid over the source shields out all the antimony-beryllium betas, b) strontium 90 was being released into type the atmosphere in large quantities during above g g ground nuclear bomb test.

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3. Af ter showing the gamma source, point out: a) Co- 53 b+0" - 51 Sb g g ,

60 is a major gamma source in the plant. b) Co-60 8 e+B +

51 52 is formed from neutron activation of materials in the plant such as stellite. t = 60 dayo

CE-LP-001 111. LESSON OUTLINE: NOTES

4. The demonstration is a good opportunity to show Biological Effective-how rapidly the count rate will fall off for ness: The time re-various types of radiation as the distance from quired for the body the source is increased. to eliminate half of the radioactive material ingested through biological CAUTION processes.

It should be pointed out to the class that the frisker is a beta / gamma detector and not used in the plant for alpha detection.

vi. Summary remarks D. Units of Radioactivity and Radiation Dose

1. Radioactivity

a. DPM - Disintegrations per minute - measure of the rate of decay of the radioactive material,

b. Curie - Atoms decaying per unit of time; equivalent to 3.7 x 10E10 or 2.22 x 10E12 atoms decaying pre minute or second.

c. Radioactive material or contamination present.

2. Radiation

a. Roentgen - Unit of exposure IR = 1000mR R = Roentgen mR = milliroentgen

b. Rad - Unit of absorbed dose; the amount of any type Exposure-Unit used to of ionizing radiation that causes the absorption define the amount of of 100 Ergs /g of body tissue. ion pair formation by X or gamma radiation 1 Rad = 1000 millirad in air. X or gamma radiation interacts with orbital electrons to create ion pairs.

c. Radiation Dose Equivalent - Rem (Roentgen Equivalent Erg - Unit of Energy Man - Quantity of any form of of ionizing radiation tha.t has the same biological effect as one roentgen of X or gamma radiation.

Rem = Rad XQF The Rem takes into account the relative biological QF = Qualify Factor damage done by absorbed doses of various types of A number scientifi-radiation as well as the differences among the types. cally determined that compensates for the

3. Unit Conversions - the prefix " milli " means one different that one-thousandth (1/1000). Therefore, a millirem (mrem) biological effects is one one-thousandth of a rem. Conversely, there caused by equal are 1000 millirem in one rem. absorbed doses of ionizing radiation.

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GE-LP-001 Ill.

LESSON OUTLINE: NOTES

a. To convert, rem to millirem, multiply the given number of rem by 1000.

b. To convert millirem to rem, divide the given number of millirem by 1000,

c. Examples:

ACTIVITY: after demonstrating examples, have trainees try additional conversions on their own.

3 rem = mrem 2000 mrem = rem 0.1 rem = mrem 500 mrem = rem NOTE: Emphasis is placed on the rem.

E. Instruments for detecting radioactivity and measuring radiation dose equivalent.

Point out that the following is just a brief intro-duction to these instruments and that more detailed instructions for the use of each one will be presented later in the class.

1. Frisker - This instrument will detect the presence of radioactive materials that emit or radiation.

Although it can detect radiation under ideal conditions ,

it is a poor detector and is not normally used as such. Radioactive contamination emits radiation, in most cases or or both. Thus, a frisker can be used to detect the presence of radioactiye contamination on personnel or equipment.

2. TLD - This device is used to measure the radiation dose (amount of radiation) received by personnel. It consists of a small plastic case containing three LiF crystals and can detect , , and neutron radiation. Only one of the three crystals is located behind a thin section of the case (called a - window) that will admit - radiation. Thus, it is possible to determine what part of the dose one receives is due to - radiation. A special instrument is required for reading the dose measured by a TLD. It cannot be read by the person wearing it.

3. Pocket Dosimeter - This device is also used to measure radia-tion dose received by personnel. Unlike the TLD, it can be read by the person wearing it. However, it measures only 3 - radiation.

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GE-LP-001 lil.

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LESSON OUTLINE: NOTES The pocket dosimeter can also measure x-rays but this is not a primary concern at a nuclear plant.

This is a good stopping point for class break.

F. Background Radiation Everyone from the moment of conception is exposed to ionizing radiation from several sources. Our environment and even the human body contains naturally occurring radioactive materials that contribute some of the back-ground radiation we receive.

Low levels of radiation that we are exposed to from natural and man-made sources is collectively referred to as Background Radiation.

Show videotape, " Radiation Naturally", then summarize using the information that appears below.

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Table 1 (Attachment 1) shows estimated average individual exposure in millirem from natural background and other sources of radiation.

The average individual in the general population receives about 0.2 rem of radiation exposure each year from sources that are a part of our natural and man-made environment. By age 20, an individual has accumulated about 4 rems. The most likely target for reduction of population exposure is medical uses.

1. Some sources of background radiation are:

a. Cosmic Rays - originate in outer space; partial Building materials protection is afforded by Earth's atmosphere. - natural radioactiv-

b. Terrestrial Radiation - from radioactive elements ity from Granite, in the earth's crust (including certain Uranium (mill building materials). tailings)

c. Radionuclidgginghebody-fromfood, g water, - man-made from phos-and air. (K ,C most abundant) phates added to materials

2. Man-Made Sources

a. Medical Irradiation - diagnostic x-rays and Medical therapeutic uses. Ba eneman 875 mrem

b. Consumer Products - television sets, luminous Chest x-ray 10-15 watch dials. Static illuminators, smoke detectors, mrem a coleman lantern mantles. Skull exam 78 mrem

c. Fallout from nuclear weapons testing. Dental x-ray (Pan)

d. Nuclear power plants. 700-800 mrem 12

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GE-LP-001 lil. LESSON OUTLINE:

NOTES (OPTIONAL)

DEMONSTRATE: Use detector on several consumer products as demonstration.

G. The Radiation Hazard - Why does it exist in nuclear power plants?

This question can be answered by considering the history of a typical nuclear power plant to include construction, fuel loading, initial start-up and subsequent operation and maintenance activities.

1. Construction Period - While the plant was under construction no nuclear fuel was on site and the reactor was, of course, not operational. At this time, the only radiation sources on site were radiography sources used by radiographers to x-ray pipe welds to check for defects.

Such sources are potentially very hazardous to people.

However, if they are properly used and controlled as required by law, they present no threat to workers in general.

2. Fuel Loading - During initial fuel loading there is a potential -radiation hazard to those working directly with the fuel due to the pr'sence e of finely powered UO 2 (Tramp Uranium) on the outside of the cladding that surrounds the fuel pellets.

3. After operation begins - Once the reactor is operational radiological problems becomes more complex and widespread.

. Radiation levels in the immediate vicinity of the operating reactor are very high. However, personnel working in the plant are effectively shielded from this high-level radiation by the primary containment structure. Biological shield.

Unfortunately, problems associated with radioactive contamination and the radiation that these contaminants emit extend beyond 16n 16 gggreactorvesselandcontainment. When nuclear fission of 0 _-- N t 59 n 939Uoccurs,anumberofradioactivefissiongroduf5f",r*

g 60 d uced. Among the more abundant ones are Sr, I and Co Co t 5.27 Cs. In addition, impurities contained in the reactor coolant vrs water, as well as the elements composing the water itself, are subject to ne'utron activation, resulting in the production of Tertiary Fission:

such activation products as:

60Co, 3H, 16 N, 597,, 65Zn, 24Na. 3 H is also produced due to tertiory fission and boron activation. Most of the fission products and activation products produced are considerably more radicactive than the new uranium fuel that was loaded into the reactor.

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r 1 GE-LP-001 111. LESSON OUTLINE: NOTES Now, ideally, all the fission products produced should remain inside the cladding which surrounds the U0, fuel pellets.

In practice, things don't quite work out tHat way. As a result of imperfections in the fuel cladding, some of the fission products leak into the reactor coolant water and are circulated throughout the primary system along with the numerous activation products described above. Thus, the stage is set for dealing with the radiological problems that will be discussed throughout this course. ,

Return to introductory slides and illustrate contain-ment structure and basic flow of reactor coolant

.during this discussion.

IV. SUMHARY Review objectives using examples to illustrate how each might be tested.

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e-GE-LP-001 TEST 1 - FUNDAMENTALS NAME

. TIME ALLOWED: 10 MINUTES ESN

1. In your own words, explain the relationship between the terms " Radioactivity" and " Radiation".

2. Write the unffs used to measure:

a. Radiation Dose -

b. Radioactivity -

3. Perform the following conversions:

a. 300 mrea = Rem

, b. 0.5 Rem = mrem

4. Circle the letter preceeding each of the following which is a source of background radiation. Beside each source circled, write the word natural or man-made.

a. Cosmic radiation

b. Building materials such as bricks and concrete

c. Medical and dental x-rays

d. Fallout from nuclear weapons testing

e. Television sets

f. Nuclear power reactors

g. Certain foods Which of the circled items represents the greatest source of radiation exposure to the average person ijs the United States?

5. Indicate the type of radiation described by each phrase by writing the word (s)

" Alpha", " Beta", " Gamma" or " Neutron" in the blank provided.

a. Positively charged particle

b. Can be shielded by plastic or plywood

c. High energy electromagnetic radiation

d. Negatively charged particles

e. Best shielding is water and other hydrogenous material

f. Primarily an internal hazard

g. Substantial thickness of lead or concrete required for shielding

h. Most common source is a nuclear reactor

1. Can be shielded by a sheet of paper 15 l- __ ___ _ _ _ _

GE-LP-001

6. A worker is performing maintenance on a valve which controls the flow of contaminated water. No water is leaking from the valve and the valve has not yet been removed from the pipe in which it is installed. To what type (s) of radiation, if any, is the worker likely to be exposed?

7. Consider the situation described above. Assume that the worker has just removed the valve, exposing an open pipe. A small amount of water and some solid residue are, visible just inside the pipe. To what type (s).of radiation, if.any, is the worker likely to be exposed?

8. Which of the following types of radiation can cause materials to become radioactive?

a. Alpha

b. Beta

c. Gamma

d. Neutron

9. Which of the following is used to detect radioactive contamination?

a. Frisker

b. TLD

c. Pocket dosimeter

d. Both b and c above

10. Which of the following is used to measure radiation dose received by personnel?

a. Frisker

b. TLD

c. Pocket dosimeter

d. Both b and c above

11. Which of the following statements is correct?

a. Radiation is found only in and around nuclear power plants

b. Radioactive contamination emits radiation

c. Radiation and contamination are the same thing

d. None of the above

12. The pocket dosimeter measures .

a. Neutron radiation

b. Alpha radiation

c. Gamma radiation

d. All of the above i

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RADIATION PROTECTION - FUNDAMENTALS TABLE 1 U.S. General Population Exposure Estimates (1978)"

AVERAGE INDIVIDUAL SOURCE DOSE (mrem / year)

Natural background (average in U.S.) 100 Release of radioactive material in natural gas, mining, milling, etc. 5 Medical (whole-body equivalent) 90 Nuclear Weapons (primarily fallout) 5-8 Nuclear energy 0.28 Consumer products 0.03 Total - 200 mrem / year

" Adapted from a report by the Interagency Task Force on the Health Effects of Ionizing Radiation published by the Department of Health, Education, and Welfare.

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