Introduction to Radiography and Safety

8/19/2019 Introduction to Radiography and Safety

1/66

Introduction toRadiography Industrial

application& Safety Aspects

1


2/66

O utline

ElectromagneticRadiation

General Principlesof Radiography

Sources of

Radiation – Gamma Radiography

– X-ray Radiography

• Imaging Modalities – Film Radiography – Computed Radiography – Real-Time Radiography

•Radiation Safety

•Advantages andLimitations

•Glossary of Terms


3/66

Introduction

Radiography uses penetrating radiationthat is directed towards a component.

The component stops some of theradiation. The amount that is stoppedor absorbed is aected by materialdensity and thicness dierences.

These dierences in !absorption" canbe recorded on #lm$ or electronically.


4/66

G eneral Principles of Radiography

Top view of developed film

X-ray film

The part is plaed !etween the

radiation soure and a piee of film"

The part will stop some of the

radiation" Thi#er and more dense

area will stop more of the radiation"

$ more e%posure

$ less e%posure

The film dar#ness

&density' will vary with

the amount of radiation

reahing the filmthrough the test o!(et"


5/66

G eneral Principles of Radiography

The energy of the radiation aects itspenetrating power. %igher energy radiationcan penetrate thicer and more densematerials.

The radiation energy and&or e'posure timemust be controlled to properly image theregion of interest.Thin Walled Area

Low Energy Radiation High energy Radiation


6/66

W hat is Radiation? Form of energy (e.g. Chemical, Magnetic,

Electrical, Heat, Sound, Radiation) Radiation Energy: Emitted by nucleus of

atom or orbital electron

Released in form of electromagneticwaves or particles

6


7/66

The Electrom agnetic Spectrum

W aveform of Radiation

NONIONIZING IONIZING

Radio

Microwaves

Inrared

!isi"le light

#ltraviolet

$%rays

Ga&&a rays

7


8/66

D ifference bet een ioni!ing and non"ioni!ing radiation

Energy le(els) Ionizing radiation has enough energy to brea

apart (ionize) material with which it comes incontact (noc o! e")

#on ionizing radiation does not

8


9/66

Sources of Radiation Exposure

#aturally occurring sources $ ground% atmosphere%cosmic

Environmental radiation $ power plants% nuclear

ships & submarine

'edical procedures (patient) $ "ray% chemo"therapy

ccupational sources (worer) " airports% metros%industrial radiography

9


10/66

Radiation Sources

Two of the most commonly used sourcesof radiation in industrial radiography are'-ray generators and gamma ray sources.*ndustrial radiography is often subdi(idedinto !X-ray Radiography" or !Gamma

Radiography"$ depending on the source ofradiation used.


11/66

)R*)+RT, *F GAMMA RA,S

Electromagnetic rays lie *"rays

+aving a ,nite energy

-ble to interact with matter

illing a of cell by splitting /#- or

0y forming free radicals

11


12/66

S+S *F GAMMA RA,S FR*M IS*T*)+S

+E,**E

/GR*01T0RE

*,0STR2

%E1/T% /RE

RESE/R%

12


13/66

LIST *F IS*T*)+S

0.66Fission

yield~ 6

Fission30 ye

ars

Cs137

0.06

4,0.052

130

barns

Tm169

(n, )Tm170127

da ys

Tm170

1.17

1.33

37barn

s

Co59 (n, )Co60

5.27 years

Co60

0.29

6o0.613

370

barns

!r 191 (n, )

!r 192

74.4

da ys

!r 192

γ -Energy

MeV

Act.crosssecti

on

ProductionProcess

Halflife

!soo"e

13


14/66

#"Ray

1enetrating electromagnetic waves $ cancause internal damage

2an pass through soft tissue% but not bone

riginate in outer part of atom

3sed in medical procedures (diagnostic% 24%Fluoroscopy" is an imaging techni6ue that uses *"rays to obtainreal"time moving images of the internal structures of a patient through

the use of a 7uoroscope)

Energy inversely proportional to wavelength

4he shorter the wave% the stronger the energy 14


15/66

G am m a Radiography

Gamma rays are produced bya radioisotope.

/ radioisotope has anunstable nuclei that does notha(e enough binding energy tohold the nucleus together.

The spontaneous breadownof an atomic nucleus resultingin the release of energy andmatter is nown as radioacti(edecay.


16/66


$cont%&0nlie X-rays$ which areproduced by a machine$ gammarays cannot be turned o.Radioisotopes used for gammaradiography are encapsulated

to pre(ent leaage of thematerial.

The radioative .apsule/ is

attahed to a a!le to formwhat is often alled a .pigtail"/

The pigtail has a speialonnetor at the other end

that attahes to a drive a!le"


17/66


$cont%&/ de(ice called a !camera" is used to store$transport and e'pose the pigtail containingthe radioacti(e material. The cameracontains shielding material which reduces

the radiographer3s e'posure to radiationduring use.


18/66


$cont%&/ hose-lie de(icecalled a guidetube is connected

to a threaded holecalled an !e'itport" in thecamera.

The radioacti(ematerial will lea(eand return to thecamera through

this opening whenerformin an


19/66


$cont%&/ !dri(e cable" isconnected to the otherend of the camera. Thiscable$ controlled by the

radiographer$ is used toforce the radioacti(ematerial out into theguide tube where thegamma rays will pass

through the specimenand e'pose the recordingde(ice.


20/66

#"ray Radiography

0nlie gamma rays$ '-rays are produced byan X-ray generator system. These systemstypically include an X-ray tube head$ a high(oltage generator$ and a control console.


21/66

#"ray Radiography $cont%&

X-rays are produced by establishing a (ery high (oltagebetween two electrodes$ called the anode and cathode.

To pre(ent arcing$ the anode and cathode are locatedinside a (acuum tube$ which is protected by a metalhousing.


22/66


23/66

#"ray Radiography $cont%&

The cathode contains asmall #lament much thesame as in a light bulb.

urrent is passed through

the #lament which heats it.The heat causes electronsto be stripped o.

The high (oltage causesthese !free" electrons tobe pulled toward a target

material 5usually made oftungsten6 located in theanode.

The electrons impactagainst the target. This

impact causes an energye'change which causes '-

0igh +letrial )otential

+letrons

-1

2-ray Generator

or Radioative

Soure Creates

Radiation

+%posure Reording 3evie

Radiation)enetratethe Sample


24/66

- unit is necessary for the measurement

of any physical 6uantity.

4he International 2ommission on

Radiation 3nits and 'easurements(I2R3) reviews and updates

""""3nits of radiology

- few of the 6uantities and units that areused in the ,eld of ionizing radiation.

UNITS AND MEASUREMENT


25/66

'ctivity $'&

*t is de#ned as the number of nuclear

transformation 5or disintegration6 per secondfor radioacti(e material.

0nit ) 7ec8uerel 5786

9 78 : 9 transformation per second

: 9 dps

;ld unit of acti(ity is urie 5i6

9 i : 9> 78

:


26/66

Exposure (X)

It is a measure of amount of photons ("rays or gamma rays) present in a locationof interest. (1hoton Flu).

Eposure is de,ned as the amount ofcharge ( in coulomb) produced by radiationin 8 g of air.

9I 3nit : 2oulomb per g (2g)

ld unit : Roentgen (R)

8 R ; 8electrostatic unit of charge(E93)

8 cc of air at (941)

; 8?"@ 2g


27/66

/bsorbed dose 5,6

It is the amount of energy absorbed perunit mass of matter at the point of interest.

,) absorbed dose

E) energy absorbed by material of

mass @m3

/ose of 8 Ay corresponds to energyabsorption of 8 Boule per 8 ilogram of theirradiated material.

D = E/m


28/66

(ER) ' $(& ER'-" inetic Energy Released in the

'edium. It is a measure of amount of total energy

transferred by photons ("rays or gammarays) interacting in the medium.

erma is de,ned as the sum of the initialinetic energies of all charged particlesliberated by radiation in material of mass8 g.

3nit : Boule per g (Bg) 9I 3nit : Aray (Ay)

Chen the reference material is air% the6uantity is called air erma


29/66

* + ITS O , '-SO R-ED D O SE

The SI unit: Gray (Gy) 1 Gy = 1 joule/kilogram

Old unit : rad (Radiation Aborbed!oe)

9 rad : 9>> ergs & gm : 9>-

A Gy

1 Gy=1"" rad(1 erg = 9>-= Boules6


30/66

O ld . + e * nits

QuantityUnit

RelationshipOld New

Radioactivity Ci ! 1 ! " #$27 % 1#&1# Ci

'%posu(e R C ) *+ 1 C *+ &1 " 3876 R

,i( *e(-a & .y 1 ,i( *e(-a " 114 R

/ose Rad .y 1 .y " 1## Rad

'!uivalent/ose

Re- 0v 1 0v " 1## (e-s


31/66

31

RT TECHNIQUES


32/66

32

CASSETTE HOLDER

FILM SCREEN

RA'IOGRA(H)

SOURCE

WELD

JOB

I#I

&R,0 ) .,, R,0


33/66

33

RT % TE*HNI+#E,

1 SWSI

CIRC. SEAM OF PIPES

FILM

4 PANORAMIC

CIRC. SEAM OF PIPES

FILM

3 DWDI

CIRC. SEAM OF PIPES

FILM

2 DWSI

CIRC. SEAM OF PIPES

FILM

- 'IRE*TIONAL

LONG ,EAM

FILM

RA'IOGRA(H)


34/66

34

RT - PLANNING

CONTROL

UNIT

CONDUIT

JOB

FILM

GUIDE

TUBE

SHIELDING

SHIELDING

STAND

TROLLEY

CAMERA

CORDONNED AREA

RA'IOGRA(H)

WELD

Ope(ato(


35/66

3

• IRI!I$% & 1' O*A+T & ,"

RA'IOGRA(H)

GAMMA RAY SOURCESGAMMA RAY SOURCES

RA'IOGRA(H)


36/66

36

GAMMA - SOURCE PRODUCTION

RA'IOGRA(H)

IRIDIUM

192

PLATINUM

192

LOADED IN

RT CAMERA ROOM TEMP. NEUTRONS

FROM REACTORSGAMMA RAYS

IRIDIUM

191

5al lie 7 days

Non(adioactive (adioactive

Non(adioactive

disposed

RA'IOGRA(H)


37/66

37

GAMMA - SOURCE PRODUCTION

RA'IOGRA(H)

NICKEL

6

COBALT

!9COBALT

6

LOADED IN

RT CAMERA ROOM TEMP. NEUTRONS

FROM REACTORS

GAMMA RAYS

5al lie yea(s

Non(adioactive (adioactive

Non(adioactive

disposed


38/66

39

CAMERA SET UP

RA'IOGRA(H)

*ONTRO

L

#NIT

.A*/

0RONT

G#I'ET#.E

,O#R*E

*AMERA

#RANI#M 1 LEA'

,HIEL'ING

TI(

GA(


39/66

Contact & /0


40/66

'lliptical & //


41/66

0in+le wall sin+le view


42/66

43

ADVANTAGES OF RT

RA'IOGRA(H)


43/66

44

2" RT - FILM IS A )+RMA4+4T R+C*R3 *FT+STI4G I4 T0+ F*RM *F 0AR3-R+)*RT"

5" T6*-3IM+4SI*4AL- IMAG+ *F 3+F+CT IS

MC0 +ASI+R A43 CL+AR T* I4T+R)R+T"

7" *)+RAT*R 3+)+43+4C+ IS MI4IMM AS +AC0

FILM IS 8ALIFI+3 6IT0 .)+4+TRA M+T+R/

9" +:ALATI*4 *F 6+L3 IS )*SSI;L+ AT A

3ISTA4T )LAC+ A6A, F*RM


44/66

4

LIMITATIONS OF RT

RA'IOGRA(H)


45/66

46

=" ;*T0 SRFAC+S *F T0+


46/66

47

$ '/ 0UR:,C' ;N/;C,


47/66

48

RADIATION SAFETY

RA'IATION ,A0ET)


48/66

49

'I,(LA) RE' WARNING LIGHT AT ENTR) (OINT4

SAFE PRACTICE

RA'IATION ,A0ET)

1


49/66

#

'I,(LA) RADIATION BOARD

AT ENTR) (OINT4

2

SAFE PRACTICE

RA'IATION ,A0ET)

R , / ; , < ; O

N

* ' ' > , ,


50/66

1

*OR'ON % O00 ,A0E 'I,TAN*E WITH 0LAGGE' %

RO(E 0OR LO*ATION, OTHER THAN EN*LO,#RE4

"

SAFE PRACTICE

RA'IATION ,A0ET)


51/66

2

E!A*#ATE *OR'ONNE' O00 AREA .E0ORE,TARTING O0 RA'IOGRA(H)4

#

SAFE PRACTICE

RA'IATION ,A0ET)

NO

OCCUPANCY ZONE

P i ibl di ti d


52/66

Perm issible exposure radiation doses

3

+yes=@? mSvS#in

@?? mSv

+l!owsto hands@?? mSv

neesto feet

@?? mSv

Corers

Eecti(e dose A> mS(&yr a(eraged

o(er D years D> mS( in any single

yearE8ui(alent dose

to the lens of the eye

9D> mS(&a e'tremities 5hands

and feet6 or the sinD>> mS(&a

-pprentices andstudents of 8D " 8>

years of age Eecti(e dose

mS(&a in a year E8ui(alent dose

to the lens of the eyeD> mS(&a

e'tremities 5handsand feet6 or the sin


53/66

Public Dose Lim its

4

+embers of the public Eecti(e dose

8 mS(&yr in special

circumstances D mS(

in a single yearpro(ided that 9mS(&yr a(eragedo(er D years is note'ceeded

E8ui(alent dose to the lens of the

eye 9D mS(&yr e'tremities 5hands

and feet6 or the sinD> mS(&yr


54/66

Bioloical Effects of Radiation Somatic

-!ects cells originallyeposed (cancer)

-!ects blood% tissues%organs% possibly

entire body E!ects range from

slight sin reddeningto death (acute

radiation poisoning)

Genetic -!ects cells of

future generations

eep levels as lowas possible (wearlead)

Reproductive cellsmost sensitive


55/66

Effects of ioni!in radiation is

determ ined b" Energy of radiation 'aterial irradiated

ength of eposure 4ype of e!ect /elay before e!ect seen

-bility of body to repair itself

6


56/66

Basic Safet" #actors

eep eposures -s ow -s Reasonably-chievable (/1/R/)

4ime " eep eposure times to a minimum

/istance " Inverse s6uare law: by doublingdistance from a source% eposure is dec by afactor of @

9hielding $ wear lead$ use lead wall

7


57/66

Radiation E'posure Eects on Personnel

?"?.


58/66

9

International 5 .lac6 7 )ellow

#4,4 5 Magenta 7 )ellow

Radiation ,y&"ol


59/66

$ onitorin %nstrum ents

1ersonal monitoring: Film badges% bracelet% rings

1ocet dosimeter

6#


60/66

Basic Safet" #actors

9hielding

61

RA'IATION ,A0ET) 3


61/66

62

RA'IATION ,A0ET)

UNDERSTANDING RADIATION EFFECTS

3

# ? chance o death

4= ## = ### - R

8 in a single shot 9

ocal (eddenin+ o s@in

1= #= ### - R

8 in a single shot 9

oss o e(tility

6= ##= ### - R8 in a single shot 9

RA'IATION ,A0ET)


62/66

63

=" C*4TACT ,*R S)+R:IS*R"

5" GI:+ F*LL6I4G 3+TAILS T* S)+R:IS*R• 60+R+ 0+ 6AS STA,I4G B• 0*6 MC0 TIM+ 0+ 6AS STA,I4G B•

0*6 A43 60+4 0+ CAM+ T* 4*6 A;*T RT B

7" S)+R:IS*R 6ILL C*4SLT RS* *F 43+

9" RS* 6ILL CALCLAT+ RA3IATI*4 3*S+ R+C+I:+3 A43 C*M)AR+

IT 6IT0 A44AL 3*S+ LIMIT

@" RS* 6ILL GI:+ T0+ 3+TAILS T* S)+R:IS*R

RA'IATION ,A0ET)

INCIDENTAL EXPOSURE TO RADIATION

RA'IATION ,A0ET)


63/66

64

RA'IOGRA(HER

24 (#T LIGHT 7 RO(E

34 !A*ATE THE AREA .E0ORE RT

:4 O(ERATE *AMERA

,ITE IN*HARGE

24 E,TIMATE AREA 0OR *OR'ONING

34 GI!E RT TE*HNI+#E

:4 ARRANGE ,HIEL'ING 0OR RA'IATION

R,O

24 GI!E ,A0E

(RO*E'#RE 0OR RT 34 'E,IGN EN*LO,#RE, AN' GET .AR*

A((RO!AL

:4 *O%OR'INATE WITH

A#THORITIE,

;4 E'#*ATE (ER,ONNEL A.O#T RA'IATION

RA'IATION ,A0ET)

RESPONCEBILITIES OF RADIATION PERSONNEL

RA'IATION ,A0ET)


64/66

6

RA'IATION ,A0ET)

COMPETANT AUTHORTY FOR RADIATION SAFETY

, ' R

• :(a-es (e+ulations and

a-ends (ules

• /i(ects ,RC to i-ple-ent

the (e+ulations

•

>uAlication o codes andstanda(ds

, R C

• ,pp(oves saety

p(actices

• 0u(vey o (adiation &

wo(@ places

• Ce(tiication o (adiation pe(sonnel


65/66

66

RESPECT BUT

DO NOT FEARRADIATION


66/66

T%/F 2;0

Introduction to Radiography and Safety

Documents

Transcript of Introduction to Radiography and Safety