rt 1 discussion

8/12/2019 RT 1 Discussion

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Select the most appropriate answer from the following:

RADIATION CONCEPTS

Gamma emitting radionclides are widel! sed forindstrial radiograph!" #h! are

the! sita$le%

a) Because of the significant penetrating power of gamma radiation.

b) Because such radionuclides are widely available and are inexpensive.

c) Because all of the emitted radiation is absorbed in the sample under investigation.

d) Because they emit electromagnetic radiation.

Isotopes of an element ha&e

a) the same mass number but different atomic number

b) same atomic number but different mass number

c) same atomic number and same mass number

d) different atomic number and different mass number

In the isotopes of an element the nm$er of protons will

$e

a) same

b) different

c) greater than the number of electrons

d) never equal to the number of neutrons

The half'life of iridim'()* is +, da!s" The acti&it! of an iridim'()*sorce on the (

-ne is .+/ G01 " #hat will the appro2imate acti&it! $e on the (.

Agst %

a) 296 GBq b) !" GBq c) !" #Bq d) $%& GBq



#hat 3ind of e2posre does one recei&e in indstrial

radiograph! %

a) 'nternal exposure as a result of radioactive contamination

b) (either external nor internal

c) xternal and internal exposure are equally li*ely.

d) xternal exposure.

The radiograph! sorces4 5/Co and ()*Ir

a) occur in nature

b) are produced in nuclear reactors

c) are produced by + ray machines

d) are produced be medical cyclotrons



The damaging effects of the radiations sed in

indstrial radiograph! are cased $!

ioni6ation" #hat is ioni6ation %

a) ,he process by which radioactive materials are created.

b) - form of particle radiation.

c) ,he process where sufficient energy is imparted to an

atom to remove an orbiting

electron from the electric field of the nucleus.

d) ,he absorption of radiation energy in sample materialsunder radiographic

inspection.



#hat is radioacti&e contamination %

a) - form of particle radiation

b) ,he process of ioniation.

c) lectromagnetic radiation.

d) ,he spread of unsealed radioactive material.

RADIATION 78ANTITIES AND 8NITS

#hich of the following terms represents the amont of a

radionclide at an! gi&en

time%

a) quivalent dose

b) xposurec) /ievert

d) -ctivity



The SI nit of acti&it! is the $ec1erel" The acti&it! of

gamma sorces sed for

indstrial radiograph! is sall! of the order of :'

a) GBq 0Gigabecquerel)

b) #Bq 0#egabecquerel)

c) 1Bq 0*ilobecquerel)

d) Bq 0microbecquerel)

#hich of the following sorces has the highest acti&it! %

a) % ,Bq obalt36&

a) % i obalt36&

b) %9! GBq obalt36&

c) % i 'ridium392



The term effecti&e dose is sed to descri$e whole'$od!

radiation dose" #hat is the SI

nit of effecti&e dose %

a) /ievert 0/v)

b) Gray 0Gy)

c) Becquerel 0Bq)

d) urie 0i)

#hat is dose'rate%

a) ,he spread of unsealed radioactive material.

b) - measure of the dose received at a location over a

period of time.

c) ,he amount of a radionuclide at a given time.

d) - measure of the radiation energy absorbed by a target.



T9E DAAGING E;;ECTS O; RADIATION

#hat is a stochastic <pro$a$ilistic= radiation effect %

a) 4ne that will not occur below a certain threshold level of

dose.

b) - radiation burn.

c) 4ne which only occurs following an inta*e of

radioactive materials

d) 4ne where the probability of the effect occurring is proportional to the sie of the dose received but for which

there is no threshold level of dose.



#hat is a deterministic radiation effect %

a) 4ne that will not occur below a certain threshold level of

dose.

b) - radiation burn.

c) 4ne which only occurs following an inta*e of

radioactive materials

d) 4ne where the probability of the effect occurring is

proportional to the sie of the dose received but for which

there is no threshold level of dose.

#hat is the primar! re1irement on radiation

protection and safet! %

a) ,o *eep individual doses below dose limits.

b) ,o *eep individual doses as low as is reasonablyachievable.

c) ,o ensure that deterministic effects will not occur.

d) ,o ensure that individual doses do not exceed &.& m/v.



#hat will $e the effect on an indi&idal following a

whole $od! radiation dose of

(// mS& %

a) ,emporary loss of hair

b) ,here will be no effect.

c) /mall increase in the ris* of developing cancer in later

life.

d) /evere radiation sic*ness.

INTROD8CTION TO >EGIS>ATION

In terms of radiation protection and safet!4 indstrial

radiograph! is considered to $e

a ?practice@" #hat is a practice %

a) -n activity that introduces additional sources of

exposure.

b) - measure ta*en to reduce individual exposure.

c) -ny new activity involving radioactive materials

d) -ny activity which could result in radiation exposures to

members of the public.

#ORP>ACE ONITORING



Dring rotine monitoring arond a shielded enclosre

a &ale of 5/ /v5h is measred arond the access door"

The dose that wold $e recei&ed $! a person who wor3s

there for (B mintes is

a= (B /v

b) " /v5h

c) 9&& /v

d) " m/v5h



A significant proportion of accidental e2posres in

indstrial radiograph! occrs as a reslt of inade1ate

dose'rate monitoring" #h! is dose'rate monitoring

essential %

a) ose3rate monitoring is the only effective method of

assessing the level of radiation haard in a wor*ing area

b) 't is required by the 7egulatory -uthority

c) 't is the only way of confirming that all safety and

warning systems are operating satisfactorily

d) 't is the only means of assessing the dose received by

radiographers

The acti&it! of an iridim'()* sorce is +, G01" The

radiation le&el at ( m from the sorce is

a) 2& m/v5h

b) & m/v5h

c) " m/v5h

d) 2 m/v5h



The radiation le&el at ( m from an iridim'()* sorce is

B/ mS&h" The acti&it! of the sorce is

a) 8$ GBq

b) $% GBq

c) 8$& GBq

d) && i



TRANSPORT of RADIOACTIE ATERIA>S

The maorit! of gamma sorces sed for indstrial

radiograph! are ?special form@

sorces" #hat is meant $! ?special form ? %

a) ,he sources do not require any special containers or

pac*aging in order to be

transported

b) /pecial form sources may only be transported by roadthey are not suitable for

transport by any other means

c) /pecial form sources have been constructed in

accordance with rigorous tests

specified in the '-- ,ransport 7egulations

d) /pecial form sources have an activity below specifiedlimits.



The dose'rate at the srface of a gamma sorce

transport container is (F/ mS&h and

the dose'rate at ("/ meter from the srface is 5/

microS&h" #hat is the transport inde2 <TI=%

a) 6

b) !&

c) 2

d) &.6

The transort inde2 <TI= for a gi&en sorce container is

/"B" #hat categor! of container

la$el shold $e sed on the container %

a) :hite3'

b) ;ellow3''

c) ;ellow3'''

d) (one is required.



INDIID8A> ONITORING

Dring which of the following scenarios mst an

indstrial radiographer not wear his

dose meter %

a) :hile entering a controlled area

b) :hile entering a supervised area

c) :hile transporting a source in its container

d) :hile undergoing a medical x3ray

#hat is an o&ere2posre %

a) - radiation dose in excess of m/v

b) - radiation dose which exceeds the dose limit specified by the 7egulatory -uthority

c) - radiation dose which results in deterministic effect

d) - radiation dose which results in a stochastic effect



PRINCIP>ES of PROTECTION

The dose'rate at ("/ meter from a ,// G01 sorce is B/

mS&h " #hat is the dose'rate

at *"/ meters from an F// G01 sorce <same

radioncclide= %

a) "& m/v5h

b) 2" m/v5h

c) 2." m/v5h

d) 6.2" m/v5h

The gamma dose'rate at ("/ meter from an F// G01

iridim'()* sorce is (// mS&h"

#hat dose wold a radiographer recei&e if he stood at

*"/ meters from the e2posed

sorce for * hors%

a) && m/v

b) "& m/v

c) "& /v

d) 2." m/v



The otpt of a .//34B mA 2'ra! set is +"B mS&h at ("/

meter" The 9T for .// 3 2ra!s is +"B cms of lead"

#hat wold the dose'rate redce to after transmission

throgh (, cms of lead %

a) 8.$" /v5h

b) .!! /v5h

c) .!! m/v5h

d) &.9% /v5h

The otpt of an 2'ra! set operating at (B/ 34 (/ mA is

(/ S&h at ("/ meter" #hat is

the otpt if the set is operating at (B mA %

a) & /v5h

b) " /v5h

c) " /v5h

d) "& /v5h



The radiation le&el at a location is ,/ mS&h" The

shielding re1ired to redce it to ( S&h is

a) 2 <=, > ,=,

b) 2 ,=, > 2 <=,

c) 2 <=, > 2 ,=,

d) 2 ,=, > <=,

PRACTICA> PROTECTION

#hat is the primar! re1irement for radiation

protection and safet! in indstrial

radiograph! %

a) ,o use gamma sources in preference to x3ray sets

b) ,o *eep radiation exposures as low as reasonably

achievable

c) ,o have good local rules

d) (ot to exceed dose limits specified by the 7egulatory

-uthority



#hich of the following statements is tre %

a) Beam collimation is not required for radiography in

shielded enclosures

b) ollimation is only necessary when panoramic

exposures are required.

c) Beam collimation should be used whenever practicable

d) Beam collimation is only required during site

radiography



SA;ETH and SEC8RITH of SO8RCES

#hich of the following wold $e sita$le for the storage

of gamma sorces sed for

indstrial radiograph! %

a) - loc*able filing cabinet made from " mm thic* steel

b) - bric* building used to store site explosives and plant

machinery

c) - small otherwise empty loc*able room with wallsconstructed of approximately 2" cms of concrete

d) - des* drawer



#h! is it important to ha&e good sealed sorce accontanc! %

a) /o that the whereabouts of radioactive materials are *nown at all

times and any losses may be quic*ly identified b) /o that the total inventory of sources held by the licensee is

*nown

c) /o that the number of radionuclides held on site is *nown

d) /o that there is an indication of the radiation haard on the

premises



EERGENCH P>ANS

Emergenc! plans shold specif! the actions re1ired to

minimi6e the conse1ences

of an accident" #hen damage to an 2'ra! set is

sspected4 following a fire or other

accident4 which of the following actions shold $e

carried ot first %

a) (otify the 7egulatory -uthority ? b) (otify the 7@4

c) 'solate the set from the power supply in order to prevent

further use

d) #a*e an assessment of potential exposures in the event

of use.

The annal a&erage dose limit for occpational

e2posre is

a) m/v

b) "& m/v

c) 2& m/vd) && m/v

The annal a&erage dose limit for p$lic e2posre is



a) m/v

b) " m/v

c) 2 m/v

d) & m/v

Dose limits for occpational e2posre

a) includes only the dose received during wor* with

radiation

b) includes 0a) and the dose from natural bac*ground

radiation

c) excludes 0a) and includes the dose from natural

bac*ground radiation

d) are the same for public exposure also



ar3 tre or false

. :hen an +3ray machine is switched off radiation

emission from the machine stops.

2. ,he activity of a source becomes A of the original

value after 2 half lives.

8. 'f the energy of gamma radiation is more it can

penetrate a material more.

%. ,he half value thic*ness reduces the intensity of

radiation to half the original value.". 'n the isotopes of an element the number of protons

will be different.

6. 'n the isotopes of an element the number of neutrons

will be different.

$. 7adiation causes biological effects in the person who

received the dose.

!. ,he unit of absorbed dose is Gray

9. ,he unit of equivalent dose is Becquerel

&. ,he unit of activity is /ievert

. ,he annual average dose limit for occupational

exposure is 2& m/v.

2. ,he annual average dose limit for public

exposure is m/v.

8. ,he dose limits specified for wor*ers excludes

natural bac*ground dose.



%. ,he dose limits specified for public includes

natural bac*ground dose.

". ven a small dose has a small probability of

causing cancer in the exposed person.6. 'f a radiography company has enough area

monitors there is no need for individual monitors.

$. 7adiography sources have to be designed and

manufactured to meet '/4 or equivalent standards.

!. ,he radiation level at 2 m from a source would be

become half after one half life.

9. ,he benefits from industrial radiography carried

out according regulatory standards are more than the

ris* resulting from industrial radiography.

2&. ,wo ,=,s reduce the radiation level by &.

2. or reducing the radiation level from 2& C/v5h to

C/v5h the shielding required is ,=, > 2 <=,.

22. Dicence is required for handling radiographysources.

28. (o licence is required for handling + ray

machine.

2%. 'f a person has received a radiation dose of more

than 2"& m/v he should be sent for blood test.

2". ,he ,D badge is used for conducting routinearea survey of a radiography facility.

26. 4ne /v of gamma dose is equivalent to one /v of

alpha dose.



2$. 4ne Gy of alpha dose is equivalent to 2& Gy of

gamma dose.

2!. /urveymeters measure the radiationlevel in

m/v5h.29. ,D badge measures the radiation level in

m/v5h.

8&. :e receive natural radiation from the stars and

the earth.



Part C

Answer an! * 1estions from Part C"

Each 1estion in Part C carries (/ mar3s"

. escribe in & lines the actions you will ta*e if during

radiography wor* the source gets stuc* in the guide tube.

2. ,he radiation level at 2 m from a cobalt36& source is %&&

m/5h. -nswer the following questionsE

a) at m from the source what would be the radiationlevel?

b) at % m from the source what would be the radiation

level?

c) if a person has to wor* at % m from the source for 2

hours how much dose will he get?

d) if the radiation level at % m from the source has to be

reduced to m/v5h how many ,=, or <=, should be provided for shielding?

e) if the radiation level at % m from the source has to be

reduced to & C/v5h how many ,=, or <=, should be

provided for shielding?



8. 'f you are given a gamma source a radiation

surveymeter and some lead sheets describe how you will

find out the <=, of lead for the radiation from the source.

%. :hat are the precautionary measures would you ta*e for

radiation safety before starting the operation of a

radiography device for open field radiography?

". ,he radiation level at 2 m from an iridium392 source is

&& m/v5h. -nswer the following questionsE

a) :hat is the radiation level at m from the source?

b) :hat is the activity of the source?

c) :hat is the radiation level at % m from the source?

d) 'f a radiographer wor*s at % m from the source for 2

hours how much dose will he receive?

e) 's the dose more than the average annual dose limit for

occupational exposure?

6. :rite & lines on some of the important biological

effects of radiation.

rt 1 discussion

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