SouthwestemEn i i CA SUBSIDIARYOF CRONUSINDUSTRIES,lNC. g neer ngo.

2702 WEST 9th STREET

' ' JOPLIN, MISSOURI 64801TELEPHONE e 417 782-5080EKJCTMGDJanuary 12, 1987

United States NuclearRegulatory Commission

Region IIINuclear Materials Safety &

Safeguards Brench799 Roosevelt RoadGlen Ellyn, Illinois 60137

Reference: License No. 24-19500-01

Gentlemen:

This letter is in reference to the phone conversation with W. P. Reichold ofyour office on November 25, 1986, requesting additional information on South-Western Engineering Company's Radiographer Training Program.

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As a result of the NRC Safety Inspection of June 10 & 11, 1986 by Mr. Reicholdand D. R. Gibbons of NRC, a discrepancy was found in the answer key of the teston two (2) questions. I feel at this time it should be noted again, that thisbeing the third correspondence involving additional information to Mr. Reicholdon SEC0's Radiographer Exam which was reviewed and approved by the NRC Mater-ials Licensing Section, Mr. John R: Madera April 21, 1986 in accordance withAppendix A 10 CFR Part 34.

Find attached a copy of revised Radiographer Exam with answers submitted at thistime for review by NRC and Mr. Reichold.

Upon review and approval of exam and notification of acceptance, Southwestern En-gineering Company at that time will submit a request for an amendment to incorp-orate the revised Radiographer Exam into the structure of Southwestern Engineer-ing Company Radiographer Training Program.

Other additional information requested by Mr. Reichold was explained in lengthduring the June 10 and 11, 1986 Safety Inspection, that the occurrence in questionwas never documented, but only mentioned briefly during a monthly plant safety

,g meeting. Also, it should he stated that Personnel involved were NOT knowledge-o n. able of Radiation Safety Procedures, and have no way of knowing if a violation@ or exposure even took place at that time. The Radiographer who would have com-g mitted the violation is no longer employed at SEC0 as of August 7,1985, which <

j again was explained during the June 10 and 11,1986~ Safety Inspection.enigg Hopefully, with attached information and previous phone discussions and writteno in correspondences, that this will satisy both the NRC and Mr. Reichold that the

8@ n '. new " Radiation Safety & Training Program" which Southwestern Engineering Companyog employees at this time, and was approved by the " Materials Licensing Branch" of

| Ea:m NRC is a safe and effective program concerning the protection of Shop Personnel,

| and handling of Radioactive Material in a safe and cautious manner.Si cerely,

.51f M@| Tim L. Harris pg 14 gft| Radiation Safety Officer|

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| EXAMINATI0fl FOR RADIOGRAPHER'

| NDT LEVEL II SPECIFICf

Read the question. Select the correct answer (s) or write your answer in t'hespace provided. hiae limit is one hour.

1. Name three NDT inspection forms which are commonly used at SouthwesternEngineering Company in recording radiographic examination results. I

1. Q.C. 401 $

2. R.T. Reader (Technique) Sheet

3. Radiographic Request

b2. Name two radiation sources which are used at Southwestern Engineering Company.

1. IR-192 -

2. C0 $_

3. Describe in general terms, the type of storage area which should be used for .

unexposed or unprocessed film.

Dry, cool area shielded from all radiation.

(X or Gamma)

4. What is the minimum radiographic film density permitted by ASME Code? 2.0What is the maximum? 4.0 How do you determine density in a radio-.

graph? Densitometer

5. List at least five identification items which must appear on each radiograph aspart of the film identification.

1. Job Number

2. Date

3. Company flame

4. Weld Seam'

- 5. Welder I.D.

6. What ASME method or standard (letter and numerical designation) applies to:

Penetrameter design ASME Sec. V Art. II

Film processing ASME Sec. VIII Div. I

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7. When a radiograph is to be viewed 'for acceptance and a viewer is not readilyavailable, what should you do?

Acquire one before interpretation-

8. Define the term " Radiographic Contrast".

Measured difference in film blackening from one area to another.

9. Explain what is meant by diagnostic film length: Weld seam between

number identification.

10. One method of reducing radiographic contrast is to:

a. increase the distance between the radiation source and the objectb. decrease the distance between the object and the film -

O Decrease the wavelength of the radiation used,.

d. Increase development time within manufacturer's recommendations -

11. When radiographing to the 2-2T quality level, an ASME penetrameter for 2.5 inchsteel has a thickness of:

a. one half inchb. 2.5 mils. 5 mils

50 mils

-12. A good. cobalt-60 shot is made on a 3" steel casting using an exposure time of 10minutes and a source-to-film distance of 36 inches. If it is necessary to change

- the. source-to-film distanc'e to 24 inches, what exposure time would produce asimilar radiograph if all other conditions remain the same?

a. 1.6 minutesD 4.4 minutesc. 6.4 minutesd. 8.8 minutes

13. Name six welding defects that can be detected by radiography.# 1. Crack 4. I.P.

2. Slag 5. Undercut

3. Porosity 6. Burn-through

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14. Name four casting defects that can be detected by radiography.

1. Porosity 3. Slag.

2. Shrinkage 4, Sand Inclusions, etc.

15. Describe the purpose of a film badge. To oive a month by month

read out of accumulated radiation exoosure.

16. Describe the purpose of a dosimeter To aive an on-site and daily readina

of accumulated radiation exoosure.

17. Lead screens are put in direct contact with the film to:

a. Increase the photograph action on the film.b. Absorb the longer wavelength scattered radiationc. Intensify the photographic effect of the primary more than the scattered

radiation.i

O All of the above.18. With respect to quality, what three factors must be considered in selecting

a source-to-film distance?.,

a. Source activity, type of film, type of screensb. Source activity, size of film, thickness of materialc. Source size, source activity, specimen-to-film distance

@ Source size, specimen thickness, geometric un~ sharpness

19. Prepare a rough diagrammatic sketch showing the relative location of the radi-ation source, penetrameters, film and a four inch diameter butt-welded pipe,

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20. Match the weld reinforcement thickness to the following plate thickness.

Up to 1/2" C a. 1/8"

,; Over 1/2" - 1" D b. 5/32"

Over 1" - 2" A c. 1/16"

Over 2" B d. 3/32"

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SouthwesternEn i i CA SUBSIDIARYOF CRONUS INDUSTRIES,1NC. g neer ngo-

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COMPANY

DATE

EXAMINATION FOR RADIOGRAPHER

NDE LEVEL II GENERAL

Read the questions. Select the correct answer (s) or write your answer inthe space provided. Time limit one hour.1. The general method of producing X-rays involves the sudden deceleration

of high velocity electronsin a solid body called a:

a. focus cupb. filamentO targetd. cathode

2. A cobalt-60 gamma-ray source has an approximate practical thicknesslimit of:

a. 2-1/2 inches of steel or its equivalentb. 4 inches of steel or its equivalent

@ 7-1/2 inches of steel or its equivalent''

d.11 inches of steel or its equivalent

3. The velocity of electrons striking the target in an X-ray is a function of:

a. The atomic number of the cathode materialb. The atomic number of the filament material

@ The voltage difference between the cathode and anoded. The current flow in the rectifier circuit

4. Cobalt-60 is reported to have a half life of 5.3 years. By how much shouldexposure time be increased (over that used initially to produce excellentradiographs when the Cobalt-60 source was new) when the source is two years old?

a. No change in exposure time is neededb. Exposure time should be about 11 per cent longer

O Exposure time should be about 37 per cent longerd. Exposure time should be from 62 to 100 per cent longer

5. The gamma ray intensity at on'e foot from a one curie source of radioactivecobalt 60 is nearest:

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$ 15 roentgens per hourb. 1,000 roentgens per hourc. 1 roentgen per minuted.10 milliroentgens per day

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6. Thin shets of lead foil in intimtate contact with X-ray film duringexposure increase film density because:

a. They fluoresce andemit visible light which helps exposethe film

b. They absorb the scatter radiation1. They prevent bach-scattered radiation from fogging the film

@ They emit electrons when exposed to X and gamma radiationwhich help darken the film.

7. A voltage selector consisting of an fron core transformer with a singlewinding having a series of taps at various points on the winding is called:

a. A high voltage transformerb. A filament transformer

. An autotransformerA power transformer

8. In comparison with lower-voltage radiographs, high energy radiographs show:

a. Greater contrast@ Greater latitudec. Greater amounts of scatter radiation relative to primary

beam intensity !,

d. None of the above

9. Filters placed between the X-ray tube and specimen tend to reduce scatterradiation undercutting the specimen:

@ By absorbing the longer wavelength components of the primary beamb. By absorbing the shorter wavelength components of the primary

beamc. By absorbing back-scatter radiation

_d. By decreasing the.. intensity fo the beam

10. Images of discontinuities.close.to the source side of the speciment become lessclearly defined as:

@1. Source-to-object distance increasedThe thickness of the specimen increasesc. The size of the focal spot decreasesd. The thickness of the speciment decreases

11. As the effective energy of the radiation increases:- @ Film graininess increases'

b. Film graininess decreasesc. Radiographic definition increasesd. Film speed decreases

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12. In order to Utilize the principles of geometric enlargement (placing tke_.film at a distance from the specimen):

- ,.a. The source-to-specimen distance must be one-half the source-

to-ffim distance

@ A magnetic focusing,c6il must be used near the port of the'X-rayThe source of radiation must be extremely smallc.

tubed. The specimen must be of uniform thickness

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13. The radiographic absorption of a material will tend to become less dependentupon the composition of the material when: -

The kilovoltage is increased -

. The source-to-film distance is decreasedc. The kilovoltage is decreasedd. A filter 'is used

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14. X-ray exposure holders and cassettes often incorporate a sheet of" lead. frail inthe back which is not in intimate: contact with the film. The^ purpose of thissheet of lead foil is: .

1. To act as an intensifying screen ;,G'Toprotectthefilm-frombackscatter ^

c. Both a and b aboved. Neither a or b above-

15. A radiograph made with an exposure of 12 ma-min. has a dens ty of 0.8 in the ~

region of maximum interts't. It is desired to incrase the density to 2.0 inthis area. By reference to a characteristic curve of the film, it is foundthat the differenc~e in log E between a density of 0.8 and 2,0 is .076. Theantilogarithm of log 0.76 is 5.8. What must the new exposure time be to pro-duce a radiograph with a density of 2.0?

I jt. 9.12 ma-min.| @ 21.12 ma-min.

c. 69.6 ma-min.d. !C'ina-min.

16. In order for a radiograph to have a penetrameter sensitivity of 2-2T or better:

a. The radiographic procedure has to be able to differentiate a 2- 4

@ por centxdifference in specimen thicknessThe radiographic procedure must be able to define the 2Tinole. in a penetrameter which ir 2 per cent of the thickness of the-

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specimen.c. _The radiograph must be able to distinguish a discontinuity ~with'

| a length equivalent to 2 per cent of the specimen thicknessc. None of the above choices are correct

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17. The term which describes the total absorption of the useful beam caused bythe X-ray tube wall, the wall of the tube housing, and any material betweenthe tube and housing is:

a. Stray absorptionb. Soruce absorption. Characteristic filtration

Inherent filtration

18. The interval between the time a film is placed in a fixer solution and thetime when the original diffuse, yellow milkiness disappears is known as:

$ clearing timeb. fixing timec. hardening timed. oxidation time

19. Excessive subject contract caused when the thickness range in the test specimenis too great for the radiation quality used may be corrected by:

a. increasing the kilovoltageb. using a filter at the X-ray tube and increasing the exposure time

@ both a and b are methods for correcting excessive subject contrastd. decrease the exposure time

20. The quantity of radiation striking a unit area of film:

@ is the product of radiaiton intensity and timeb. is the intensity per unit of timec. is directly proportional to intensity and inversely proportional

to timed. varies exponentially with time and directly with intensity

21. Which of the following factors will not-materially influence the image densityof a radiograph?

a. the type of film used

@ The size of the filmc. the total amount of radiation emitted by the X-ray or gamma-ray

sourced. The intensifying action of the screen

22. Because of geometrical factors such as source, size, source-to-specimen distanceand specimen-to-film distance, there can be a lack of perfect sharpness at the

- edges of indications. The unsharpness caused ~by geometrical factors may bereferred to as the:

a. astigmatic effect@ prenumbral shadowc. focus variationd. none of the abo've

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SouthwesternEngineeringCoA SUBSIDIARY OF CRONUS INDUSTRIES, lNC.

M?2B/nDiO M

23. The approximate radiographic equivalence factors for steel and copper at220kv are 1.0 and 1.4 respectively. If it is desirabale to radiograph on0.5 inch plate of copper, what thickness of steel would require about thesame exposure characteristics?

$ 0.7 in, of steelb. 0.35 in, of steel

c. 1.4 in. of steeld.1.0 in. of steel

24. It is known that the density of a film increases with increasing exposure up -

to a maximum value. Increasing the exposure beyond this point results in anactual decrose of density. This phenomena is referred to as:

a, density-intensity turnaboutb. subject contract inversionc. film contrast inversion

@ reversal

25. The quantitative measure of film blackening is referred to as:

a. definition@ photographic densityc. film contrastd. radiographic contrast

26. A curve relating density with the logarithm of exposure or or relatively ex-posure is called:

a. a sensitivity curveb. a density-exposure curve

$ an H & D curved. X-ray intensity curve

27. Which of the following ins _truments would most likely be used to detect smallleaks in a radiation barrier?

~

a. a film badgeb. a fountainpen type of ionization chamber

O a Gieger counterd. a dosimeter

28. At voltages above 400 kv., the use of lead to provide protection may presentserious structural problems. If this should be a serious problem, which of

,the follaaing saaterials would most likely be used as a substitute?

A. aluminumW concretec. steeld. boron

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:D Mm29. The slope (steepness) of a characteristic curve is a measure of:

a. subject contrast

b. radiograph.ic definitionc. radiographic contrast

$ film contrast

30. Agitation of the X-ray film during the development process by means ofmechanical stirrers or circulating pumps may:

a. speed the developing cycleb. help replenish the developer

@ cause undesirable preerential flow of developer along certain pathsd. cause reticulation

31. The activity of the fixer diminishes after being used for a period timbe because:

a. the active ingredients evaporateb. the active ingredients are absorbed by the radiograph

@ the fixer solution accumulates soluble silver saltsd. the active ingredients settle to the bottom of the tank

32. A distinctive characteristic of high voltage radiography is:

a. it results in comparatively high subject contrastb. it results in comparatively high radiographic contrast

@ it is applicable to comparatively thick or highly absorbing specimensd. all of the above are distinctive characteristic of high voltage

radiography

33. Lead screens are used for almost all exposures when using:

a. the fluoroscopic technique_ _ b. low voltage radiography

@ high voltage radiographyd. zeroradiography

34. Which of the following is the primary function of a film interpreter?

a. find perfect parts which contain no discontinuitiesb. reject parts

| @ judge the effect discontinuities and manufacturing deviations| will have on the serviceability of a part

d. determine if the proper technique has been used during an exposure|

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SouthwestemEngineeringCo*

A SUBSIDIARY OF CRONUS INDUSTRIES,1NC

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2D ;J 77335. A special form of scatter due to X-ray diffraction affects in a specimen

with large grains will result in:

1. a radiograph with poor contrast@ a radiograph of mottled appearancec. a badly fogged radiographd. a radiograph withpoor resolution

36. The half-value layer of steel for cobalt-60 is approximately 1 inch. If the

radiation level on the source side of a 3 inch steel plate is 64 R/hr., theradiation level on the opposite side is:

$ 8 R/hrb. 21-1/3 R/hrc. 10-2/3 R/hrd. 32 R/hr

37. If an exposure time of 60 seconds and a source-to-film distance of 4 ft. isnecessary for a particular exposure, what exposure time would be needed foran equivalent exposure-if the source-to-film is changed to 5 ft?

a. 75 sec.@ 94 sec.c. 48 sec.

'' d. 38 sec.

38. The energy of gamma rays is expressed by which of the following units ofmeasurement?

a. curie|

b. roentgen! c. half-life

@ kilo-electron-volts (kev) or millions of electron volte (mev)1

j 39. An X-ray film having wide latitude also has, by definition:

h. poor definitioni

icw contrast'

c. high speedi

| d. none of the above

j 40. The formula milliamperes x time is:

| distance 2l

a. used to calculate film gradient- b. the reciprocity law

|. used to determine radiographic contrast'

| the exposure factor

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SouthwestemEngineeringCoA SUBSIDIARY OF CRONUS INDUS TRIES,1NC.

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2.':) LQ P3J41. Besides serving as a filter, screens of high atomic number, such as lead

antimony, also:

a. Decrease the source-to-film distance needed for aproper radiograph

([) Provide some image intensifying actionc. Permit the use of higher speed filmd. Decrease the graininess in a radiograph

42. The specific activity of cobalt-60 depends on:

(b The time the material has been in the reactorb. The atomic number of the materialc. The ganma ray flux to which it was exposedd. The Young's modulus value of the material

43. In certain cases, it may be advantageous to pack lead shot around a speci-men. The purpose for doing this is:

a. To prevent movement of the specimenb. To increase the subject contrast1 To general small wave length X-radiation@ To decrease the effect of scattered radiation under-

cutting the specimen

44. Films that are left between lead screens too long in a high temperatureand high humidity atmosphere may:

Show increased speed but' decreased quality characteristics.

Become foggedc. Become mottledd. Show tree-shaped light areas in the finished radiograph

45. The activity of the fixer diminished after being used for a period of timebecause:

h- - -a. The active ingredients evaporate| b. The active ingredients are absorbed by the radiographI (DL The fixer solution accumulates soluble silver salts

d. The active ingredients settle to the bottom of the tank

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D~~ 2 7 2 21RADIATION SAFETY

What per'centage of the electrical energy used in t.he production of X-rays is1.converted into usable X-radiation?

a. 99%b. 50%c. 20%

@ less than 1%,

2. Radiation produced from radioisotopes can be seen in dim light.

a. true

@ false ,'

3. X and gamma radiation may be harmful to which of the following?

a. light metal such as aluminum@ human tissuec. heavy metal such as . leadd. all of the above

4. Define half value layer.'

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Thickness of material which transmits 50% of the radiation incidence upon "it.

5. If the radiation level at 4 feet from a given source is 20 R/hr, what is theradiation level at 16 feet?

a. 5 R/hrb. 10 R/hr. 2.5 R/hr

1.25 R/hr

6. List four isotopes in common usage in industrial radiography.IR-192 CS-137C0-60 Radium Thulium - 170

7. The unit of measure to determine intensity of X-ray is which of the following?

a. milliamperes,

b. kilovolts

@ potentialc.

roentgen'

.8. Given a maximum permissible dose of 150 milliroentgens per week how many hours aweek can a person work in a 6 milliroentgen field?

G. 25 hours5. 90 hours

; c. 40 hours.! d. 10 hours

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' SouthwesternEngineeringCoA SUBSIDIARYOF CRONUS INDUSTRIES,1NC. ( ,

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Radiation Safety - Page 2

9. Increasing the milliamperage setting of an. electronic X-ray unit increaseswhich of the following?

a. penetration of the produced X-raysb. availability of the electronsc. intensity of the produced X-rays

@ all of the above

10. A densitometer is:

a. a meter used to measure X-ray intensity@ an instrument for measuring film densityc. a meter used to measure the density of a materiald. a meter used to measure tube current

11. The most important factor for determining the amount of X-ray absorptionof a specimen is the:

a. thickness of the specimenb. density of the specimen

O both a and b-

f,d. Young's modulus of the material '*

12. The energy of gamma rays is expressed by which of the following units ofmeasurement?

a. curieb. roentgenc. hal f-life$ Kiloelectron volt (kev) or million electron volt (MeV)

-- 13. List three devices used to detect the presence of X or gamma radiation.i 1. Survey Meter

2. Geiger Counteri 3. DosimeterI!,

14. List three methods of minimizing exposure to radiation.TimeDistanceShielding

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15. X-ray exposure may be due to:

a. The direct beam from the X-ray tube targetb. scatter radiation arising from objects in the direct beam

@ both a and b aboved. Both a and b above plus residual radiation that exists for the_first

few minutes after the X-ray machine has been returned to the "off". position.

16. If an exposure time of 60 seconds was necessary using a 4-foot source-to-film distance for a particular exposure, what time would be necessary ifa 2-foot source-to-film distance is used and all other variables remainthe same.

a. 120 secondsb. 30 secondsO 15 secondsd. 240 seconds

17. In making an isotope exposure in an unshielded area, you find the dose rate6 feet from the source is 1200 mR/hr. What would be the dose rate 24 feet?

G 75 mR/hr''

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b. 100 mR/hrc. 200 mR/hrd. 300 mR/hr

18. Which of the following types of radiation is emitted by cobalt-60 and used innondestructive testing?

a. Neutrons@ Gamma raysc. X-raysd. Alpha particles

19. Approximately what percent of the original radioactivity is left after sixhal f-lives ?

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a. 0.005b. 10c. 33.3&2

20. The radiation intensity of a radioisotope:c

a. increases with time@ decreases with timec. is not affected as time elapsesd. none of the above

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Radiation Safety - Page 4 13 d I

21. The time required for one-half of the atoms in a particular sample of radio-active material to disintegrate is called:

a. the inverse square lawb. a curie@ a half-lifed. the exposure time

22. W. hat does the term R/hr refer to when speaking of intensity?

1 radiation limits for humans *

@ roentgens per hourc. x-rays per hourd. radiation in hydrogen

23. A cobalt-60 source has a half-life of:

a. 1.2 yea.rsb. 6 months *

@ 5.3 years,

-d.~ 75 days

24. Scattered radiation caused by any material, such as a wall or floor, on thefilm side of the specimen is referred to as:

a. primary scatteringb. undercutc. reflected scattering$ backscattered radiation

25. A general . rule used to define the amount of radiation exposure that is ex-cessive is:

a. ~ Although small amounts of radiation (0.4 R per week or less) are beneficial- - since they build up an immunity to these rays, anything above 0.4 R per

week is excessiveb. any dose over 5 R per seek is excessivec. any dose which causes a mid-range reading on a Geiger counter is excessive

@ any unnecessary exposure to radiation is excessive

26. If a piece of lead 1/2 inch thick is placed in the path of a beam of radiationemanating from cobalt-60, it will reduce the dose rate at a given location by:

' a. one third-

b. one quarterO one halfd. three quarters

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27. The most common material used to provide protection against x rays is:

a. high density brickb. an alloy of 70 percent steel and 30 percent copper

tungstenlead

28. A curie is the equivalent of:

a. 0.001 millicuries@ 1,000 millicuriesc. 1,000 megacuriesd. 100 megacuries

29. The exposure of personnel to X- and gamma radiation can be measured or moni-tored by means of:

a. film badgesb. dosimeters1 radiation exposure survey meters@ all of the above

The intensity of X- or gamma radiakion is measured in:30.

a. roentgensb. ergs

@ roentgens per unit of timed. H & D units

31. An advantage of the pocket dosimeter type of ionization chamber used to monitorradiation received by personnel is:

. -a.--it provides a permanent-record of u. cumulated dosage@ it provides an immediate indication of dosagec. it is the most sensitive detector availabled. all of the above are advantages

32. An unshielded isotope source gives a dosage rate of 900 mR per hour at 10 feet.What would the unshielded dosage rate be_at 30 feet?

a. 300 mR/hrb. 600 mR/hr

O 100 mR/hrd. 2700 mR/hre

33. The most widely used unit of measurement for measuring the rate at which the out-put of a gamma-ray source decays is the:

@ curieb. roentgenc. hal f-li fed. MeV

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34. Why is cobalt-60 used as a radiation source for medium-weight metals of thick-ness ranges from 1.5 to 9 inches?a. because of its short half-lifeb. limited amount of shielding required

@ because of its penetrating. abilityd. none of the above

35. X-rays and gamma rays always travel:

a. in pairsb. orbital spheres

@ straight linesd. none of the above

36. The term used to describe the loss of excess energy by the nucleus of radio-active atoms is called:

h decay (disintegration) ib. ionizationc. scintillationd. . activation |

37. Gamma and X-radiation interact with matter and may be absorbed by:

a. photoelectric absorption '*b. compton scattering

pair productionall of the above

38. The number of positive charges on the nucleus of an atom equals:

1 the number of neutronsQ:J the atomic numberc. the number of photons

- - --d'. the atomic weight

39. -Radiation-scattering increases as:

a. the energy of the incident radiation decreasesb. the size of the radiation field increasesc. the angle of scatter decreases

@ all of the above

40. The specific activity of an isotopic source is usually measured in:

a. million electron volts.

6 curies per gran-

c. roentgens per hourd. counts per minute

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' 41. Which of the following isotopes has the longest half-life?

a. Thulium-170b. Cobalt-60c. Iridium-192

$ Cesium-137

42. The quantity of radiation which will produce,by means of ionization, oneelectrostatic unit of electricity in 0.001293 grams of dry air is known as:

a. a millicurieb. a gamma

@ a roentgend. a curie

43. The Code ~of Federal Regulations requires that all shipping containers forradioisotopes:

a. contain provisions for sealing the lid of the containerO be fire resistantc. be shockproof

.

d. be twice as thick as, normal storage containers

44. Which of the following instruments would exhibit the best sensitivity and mostlikely be used to detect small leaks in a radiation barrier?

a. a film badgeb. a fountain pen type of ionization chamber

@ a Geiger counterd. a dosimeter

6045. Approximately how long would it take for a 10 curie C0 source to decay2-1/2 curies?

-- a. 5.3 daysb. 5.3 yearsc. 10.6 years

@ none of the above

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INSPECTOR DATE

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DENSITY

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FILM ARTIFACTS

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SOURCE

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INITIAL AND DATE ALL FILM

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RESULTS:

EXAMINER DATE

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