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In accordance with Title 10 of the Code of Federal Regulations Section 2.390, a copy of this letter and the enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html. The NRC is forwarding the individual grades to you in a separate letter which will not be released publicly. Should you have any questions concerning this examination, please contact Mr. Phillip T. Young at (301) 415-4094 or via internet e-mail Phillip.Young@nrc.gov
In accordance with Title 10 of the Code of Federal Regulations Section 2.390, a copy of this letter and the enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html. The NRC is forwarding the individual grades to you in a separate letter which will not be released publicly. Should you have any questions concerning this examination, please contact Mr. Phillip T. Young at (301) 415-4094 or via internet e-mail Phillip.Young@nrc.gov
.        Sincerely,
.        Sincerely,       /RA/
        /RA/
Kevin Hsueh, Chief      Research and Test Reactors Oversight Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Docket No. 50-243  
Kevin Hsueh, Chief      Research and Test Reactors Oversight Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Docket No. 50-243  


Line 68: Line 67:


ENCLOSURE 1 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.: 50-243/OL-15-01 FACILITY DOCKET NO.: 50-243 FACILITY LICENSE NO.: R-120 FACILITY: Oregon State University TRIGA Reactor EXAMINATION DATES: November 18 - 19, 2014 SUBMITTED BY:
ENCLOSURE 1 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.: 50-243/OL-15-01 FACILITY DOCKET NO.: 50-243 FACILITY LICENSE NO.: R-120 FACILITY: Oregon State University TRIGA Reactor EXAMINATION DATES: November 18 - 19, 2014 SUBMITTED BY:
  /RA/  12/04/2014 Phillip T. Young, Chief Examiner Date SUMMARY:
  /RA/  12/04/2014 Phillip T. Young, Chief Examiner Date
During the week of November 17, 2014 the NRC administered licensing examinations to three Reactor Operator (RO) applicants. The applicants passed all portions of the examination.
 
==SUMMARY==
: During the week of November 17, 2014 the NRC administered licensing examinations to three Reactor Operator (RO) applicants. The applicants passed all portions of the examination.
REPORT DETAILS  1. Examiners: Phillip T. Young, Chief Examiner, NRC  
REPORT DETAILS  1. Examiners: Phillip T. Young, Chief Examiner, NRC  
: 2. Results:
: 2. Results:
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DR - Rem, Ci - curies, E - Mev, R - feet 1 Curie = 3.7 x 10 10 dis/sec    1 kg = 2.21 lbm 1 Horsepower = 2.54 x 10 3 BTU/hr  1 Mw = 3.41 x 10 6 BTU/hr 1 BTU = 778 ft/lbf      °F = 9/5 °C + 32  
DR - Rem, Ci - curies, E - Mev, R - feet 1 Curie = 3.7 x 10 10 dis/sec    1 kg = 2.21 lbm 1 Horsepower = 2.54 x 10 3 BTU/hr  1 Mw = 3.41 x 10 6 BTU/hr 1 BTU = 778 ft/lbf      °F = 9/5 °C + 32  


1 gal (H2O)  8 lbm      °C = 5/9 (°F - 32) cP = 1.0 BTU/hr/lbm/°F    c p = 1 cal/sec/gm/°C T UA = H m = T cm = Qp K-1S -S = SCReff )(-CR = )(-CR)K-(1CR = )K-(1CR2211eff2eff121 seconds 0.1 = -1eff -26.06 = SUReff K-1K-1 = Meffeff10 CRCR = K-11 = M21eff e P = Pt0 P -)-(1 = P0 10 P = PSUR(t)0 K)K-(1 = SDMeffeff -  =
1 gal (H 2 O)  8 lbm      °C = 5/9 (°F - 32) c P = 1.0 BTU/hr/lbm/°F    c p = 1 cal/sec/gm/°C T UA = H m = T c m = Q p K-1 S -S = SCR eff )(-CR = )(-CR)K-(1 CR = )K-(1 CR 2 2 1 1 eff 2 eff 1 2 1 seconds 0.1 = -1 eff -26.06 = SUR eff K-1 K-1 = M eff eff 1 0 CR CR = K-1 1 = M 2 1 eff e P = P t 0 P -)-(1 = P 0 10 P = P SUR(t)0 K)K-(1 = SDM eff eff -  =
* eff*- +  =  K1)-K( = effeff KxkK - K = effeffeffeff2112 0.693 = T e DR= DRt-0 R6CiE(n) = DR2 Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question  A.001  (1.0 point)  {1.0}  Which of the following statements best characterizes Natural Circulation?      a. It needs a pump to get started.      b. The elevation of the heat source must be above that of the heat sink.  
* eff*- +  =  K 1)-K ( = eff eff K x k K - K = eff eff eff eff 2 1 1 2 0.693 = T e DR= DR t-0 R 6CiE(n) = DR 2 Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question  A.001  (1.0 point)  {1.0}  Which of the following statements best characterizes Natural Circulation?      a. It needs a pump to get started.      b. The elevation of the heat source must be above that of the heat sink.  
: c. The driving force is a difference in density.      d. Heat transfer is more efficient if steam is mixed with water.  
: c. The driving force is a difference in density.      d. Heat transfer is more efficient if steam is mixed with water.  


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==Reference:==
==Reference:==
   = (Keff1 - Keff2) ÷ (Keff1
   = (K eff1 - K eff2) ÷ (K eff1
* Keff2)      = (0.9550 - 1.0000) ÷ (0.9550
* K eff2)      = (0.9550 - 1.0000) ÷ (0.9550
* 1.0000)  
* 1.0000)  
     = -0.0450 ÷ 0.9550 = -0.0471  
     = -0.0450 ÷ 0.9550 = -0.0471  
Line 318: Line 319:
2 10 = 1,024 approximately equals 1,000  
2 10 = 1,024 approximately equals 1,000  


Question  B.006  [1.0 point, 0.333 each]  {6.0} Identify the source for the listed radioisotopes. Irradiation of air, water, or fission product (FP). a. N16 b. Ar41 c. Xe188 Answer: B.06 a. = water;  b. = air;  c. = FP  
Question  B.006  [1.0 point, 0.333 each]  {6.0} Identify the source for the listed radioisotopes. Irradiation of air , water, or fission product (FP). a. N 16 b. Ar 41 c. Xe 188 Answer: B.06 a. = water;  b. = air;  c. = FP  


==Reference:==
==Reference:==
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Technical Specifications §§ 2.1, 2.2, 3.2 and 3.7.2  
Technical Specifications §§ 2.1, 2.2, 3.2 and 3.7.2  


Question  B.008  [1.0 points, 0.25 each]  {8.0} Identify each of the following as either a Channel Check, a Channel Test or a Channel Calibration.  
Question  B.008  [1.0 points, 0.25 each]  {8.0} Identify each of the following as either a Channel Check , a Channel Test or a Channel Calibration.  
: a. Dipping a temperature detector in ice water and verifying the channel reads 32ºF (0ºF)  b. Verifying proper overlap between Nuclear Instrumentation Channels during startup. c. After receiving an alarm on an Area Radiation Monitor, you verify the reading with a hand-held meter.  
: a. Dipping a temperature detector in ice water and verifying the channel reads 32ºF (0ºF)  b. Verifying proper overlap between Nuclear Instrumentation Channels during startup. c. After receiving an alarm on an Area Radiation Monitor, you verify the reading with a hand-held meter.  
: d. Performing a reactor pool water rate-of-temperature-rise measurement, then adjusting the detectors to correct readout.  
: d. Performing a reactor pool water rate-of-temperature-rise measurement, then adjusting the detectors to correct readout.  
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Question  B.011  [1.0 points]  {11.0} According to Technical Specification 3.8.a, N on-secured experiments s hall have a reactivity worth less than ___ .  
Question  B.011  [1.0 points]  {11.0} According to Technical Specification 3.8.a, N on-secured experiments s hall have a reactivity worth less than ___ .  
: a. <$.25 b. <$.50 c. <$.75 d. <$1.0 Answer: B.11 d.  
: a. <$.25 b. <$.50 c. <$.75 d. <$1.0 Answer: B.11 d.  


==Reference:==
==Reference:==
Technical Specification 3.8.1.a  
Technical Specification 3.8.1.a  


Section B: Normal/Emergency Procedures&RadiologicalControls Question  B.012  [1.0 points, 0.25 each]  {12.0} For each event listed, identify the appropriate action the console operator shall take (according to OSTROP 1, Emergency Operating Procedures) as either SHUTDOWN (
Section B: Normal/Emergency Procedures&RadiologicalControls Question  B.012  [1.0 points, 0.25 each]  {12.0} For each event listed, identify the appropriate action the console operator shall take (according to OSTROP 1, Emergency Operating Procedures) as either SHUTDOWN (SD) the reactor or SCRAM the reactor. Assume the condition(s) has been verified.  
SD) the reactor or SCRAM the reactor. Assume the condition(s) has been verified.  
: a. Stack gas high activity. b. Stack monitor pump off.  
: a. Stack gas high activity. b. Stack monitor pump off.  
: c. Stack monitor filter failure.  
: c. Stack monitor filter failure.  
Line 398: Line 398:
Question  B.016  [1.0 points]  {16.0} Technical Specification 5.4 requires "all fuel and fueled devices not in the core shall be stored in such a way that K eff is less than -  
Question  B.016  [1.0 points]  {16.0} Technical Specification 5.4 requires "all fuel and fueled devices not in the core shall be stored in such a way that K eff is less than -  
: a. 0.80  b. 0.85  
: a. 0.80  b. 0.85  
: c. 0.90  d. 0.95  
: c. 0.90  d. 0.95 Answer: B.16 c.  
 
Answer: B.16 c.  


==Reference:==
==Reference:==
Line 468: Line 466:


==Reference:==
==Reference:==
OSU Trn Man Volume 1, Control Rod Drives, Question  C.006  [1.0 point]  {6.0} Which ONE of the following is the main function performed by the DISCRIMINATOR circuit in the startup channel?  
OSU Trn Man Volume 1, Control Rod Drives, Question  C.006  [1.0 point]  {6.0} Which ONE of the following is the main function performed by the DISCRIMINATOR circuit in the startup channel? a. To generate a current signal equal and of opposite polarity as the signal due to gammas generated within the Log-N Channel Detector.  
: a. To generate a current signal equal and of opposite polarity as the signal due to gammas generated within the Log-N Channel Detector.  
: b. To filter out small pulses due to gamma interactions, passing only pulses due to neutron events within the Log-N Channel Detector.  
: b. To filter out small pulses due to gamma interactions, passing only pulses due to neutron events within the Log-N Channel Detector.  
: c. To convert the linear output of the Log-N Channel Detector to a logarithmic signal for metering purposes.  
: c. To convert the linear output of the Log-N Channel Detector to a logarithmic signal for metering purposes.  
Line 537: Line 534:
==Reference:==
==Reference:==
OSTROP 22 Question  C.018  [1.0 point]  {18.0} Primary system water returning to the pool is ejected from an angled nozzle, causing a swirling motion of the water in the pool. Which ONE of the following is the PRIMARY purpose for this design?  
OSTROP 22 Question  C.018  [1.0 point]  {18.0} Primary system water returning to the pool is ejected from an angled nozzle, causing a swirling motion of the water in the pool. Which ONE of the following is the PRIMARY purpose for this design?  
: a. To increase the heat transfer rate due to increased convective flow. b. To decrease the activation rate of O 16 to N16 due to a decrease in time within the core. c. To increase the transport time for N 16 to reach the surface of the pool. d. To break up O 16 bubbles in the pool thereby decreasing the production of N
: a. To increase the heat transfer rate due to increased convective flow. b. To decrease the activation rate of O 16 to N 16 due to a decrease in time within the core. c. To increase the transport time for N 16 to reach the surface of the pool. d. To break up O 16 bubbles in the pool thereby decreasing the production of N
: 16. Answer: C.18 c.  
: 16. Answer: C.18 c.  



Revision as of 09:49, 9 July 2018

Examination Report, No. 50-243/OL-15-01, Oregon State University
ML14336A262
Person / Time
Site: Oregon State University
Issue date: 12/17/2014
From: Hsueh K P
Research and Test Reactors Licensing Branch
To: Reese S E
Oregon State University
Young P T, DPR/PROB, 415-4094
Shared Package
ML14245A131 List:
References
50-243/OL-15-01
Download: ML14336A262 (31)


Text

December 17, 2014

Dr. Steven E. Reese, Director Oregon State University Radiation Center, A100 Corvallis, OR 97331-5903

SUBJECT:

EXAMINATION REPORT NO. 50-243/OL-15-01, OREGON STATE UNIVERSITY

Dear Dr. Reese:

During the week of November 17, 2014, the NRC administered operator licensing examinations at your Oregon State University TRIGA reactor. The examinations were conducted according to NUREG-1478, "Operator Licensing Examiner Standards for Research and Test Reactors," Revision 2. Examination questions and preliminary findings were discussed with those members of your staff identified in the enclosed report at the conclusion of the examination.

In accordance with Title 10 of the Code of Federal Regulations Section 2.390, a copy of this letter and the enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html. The NRC is forwarding the individual grades to you in a separate letter which will not be released publicly. Should you have any questions concerning this examination, please contact Mr. Phillip T. Young at (301) 415-4094 or via internet e-mail Phillip.Young@nrc.gov

. Sincerely, /RA/

Kevin Hsueh, Chief Research and Test Reactors Oversight Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Docket No. 50-243

Enclosures:

1. Examination Report No. 50-243/OL-15-01
2. Written examination as administered cc w/o enclosures: See next page

ML14336A262 NRR-074

Oregon State University Docket No. 50-243 cc: Mayor of the City of Corvallis Corvallis, OR 97331

Division Administrator

Nuclear Safety Division Oregon Department of Energy 625 Marion Street NE Salem, OR 97301-3737

Dr. Ron Adams Interim Vice President for Research Oregon State University Administrative Services Bldg., Room A-312

100 Radiation Center

Corvallis, OR 97331-5904

Mr. Todd Keller Reactor Administrator Oregon State University

100 Radiation Center, A-100

Corvallis, OR 97331-5903

Dr. Andrew Klein, Chairman Reactor Operations Committee Oregon State University

100 Radiation Center, A-100

Corvallis, OR 97331-5904 Test, Research, and Training

Reactor Newsletter University of Florida 202 Nuclear Sciences Center

Gainesville, FL 32611

ENCLOSURE 1 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.: 50-243/OL-15-01 FACILITY DOCKET NO.: 50-243 FACILITY LICENSE NO.: R-120 FACILITY: Oregon State University TRIGA Reactor EXAMINATION DATES: November 18 - 19, 2014 SUBMITTED BY:

/RA/ 12/04/2014 Phillip T. Young, Chief Examiner Date

SUMMARY

During the week of November 17, 2014 the NRC administered licensing examinations to three Reactor Operator (RO) applicants. The applicants passed all portions of the examination.

REPORT DETAILS 1. Examiners: Phillip T. Young, Chief Examiner, NRC

2. Results:

RO PASS/FAILSRO PASS/FAIL TOTAL PASS/FAIL Written 3/0 0/0 3/0 Operating Tests 3/0 0/0 3/0 Overall 3/0 0/0 3/0 3. Exit Meeting: Phillip T. Young Gary Wachs, OSU, Reactor Supervisor

The examiner thanked the facility for their assistance ensuring the exam administration went smoothly and their feedback on the written examination.

ENCLOSURE 2 U. S. NUCLEAR REGULATORY COMMISSION NON-POWER REACTOR INITIAL LICENSE EXAMINATION FACILITY: OREGON STATE UNIVERSITY REACTOR TYPE: TRIGA DATE ADMINISTERED: 11/18/2014 CANDIDATE:

INSTRUCTIONS TO CANDIDATE:

Answers are to be written on the answer sheet provided. Attach the answer sheets to the examination. Points for each question are indicated in parentheses for each question. A 70% overall is required to pass the examination. Examinations will be picked up three (3) hours after the examination starts.

CATEGORY VALUE  % OF TOTAL CANDIDATE'S SCORE % OF CATEGORY VALUE CATEGORY 20.00 33.3 A. REACTOR THEORY, THERMODYNAMICS, AND FACILITY OPERATING CHARACTISTICS 20.00 33.3 B. NORMAL AND EMERGENCY OPERATING PROCEDURES AND RADIOLOGICAL CONTROLS 20.00 33.3 C. FACILITY AND RADIATION MONITORING SYSTEMS 60.00 FINAL GRADE TOTALS ALL THE WORK DONE ON THIS EXAMINATION IS MY OWN. I HAVE NEITHER GIVEN NOR RECEIVED AID.

CANDIDATE'S SIGNATURE

NRC RULES AND GUIDELINES FOR LICENSE EXAMINATIONS During the administration of this examination the following rules apply:

1. Cheating on the examination means an automatic denial of your application and could result in more severe penalties.
2. After the examination has been completed, you must sign the statement on the cover sheet indicating that the work is your own and you have not received or given assistance in completing the examination. This must be done after you complete the examination.
3. Restroom trips are to be limited and only one candidate at a time may leave. You must avoid all contacts with anyone outside the examination room to avoid even the appearance or possibility of cheating.
4. Use black ink or dark pencil only to facilitate legible reproductions.
5. Print your name in the blank provided in the upper right-hand corner of the examination cover sheet. 6. Fill in the date on the cover sheet of the examination (if necessary).
7. Print your name in the upper right-hand corner of the first page of each section of your answer sheets. 8. The point value for each question is indicated in parentheses after the question.
9. Partial credit will NOT be given.
10. If the intent of a question is unclear, ask questions of the examiner only.
11. When you are done and have turned in your examination, leave the examination area as defined by the examiner.

DR - Rem, Ci - curies, E - Mev, R - feet 1 Curie = 3.7 x 10 10 dis/sec 1 kg = 2.21 lbm 1 Horsepower = 2.54 x 10 3 BTU/hr 1 Mw = 3.41 x 10 6 BTU/hr 1 BTU = 778 ft/lbf °F = 9/5 °C + 32

1 gal (H 2 O) 8 lbm °C = 5/9 (°F - 32) c P = 1.0 BTU/hr/lbm/°F c p = 1 cal/sec/gm/°C T UA = H m = T c m = Q p K-1 S -S = SCR eff )(-CR = )(-CR)K-(1 CR = )K-(1 CR 2 2 1 1 eff 2 eff 1 2 1 seconds 0.1 = -1 eff -26.06 = SUR eff K-1 K-1 = M eff eff 1 0 CR CR = K-1 1 = M 2 1 eff e P = P t 0 P -)-(1 = P 0 10 P = P SUR(t)0 K)K-(1 = SDM eff eff - =

  • eff*- + = K 1)-K ( = eff eff K x k K - K = eff eff eff eff 2 1 1 2 0.693 = T e DR= DR t-0 R 6CiE(n) = DR 2 Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question A.001 (1.0 point) {1.0} Which of the following statements best characterizes Natural Circulation? a. It needs a pump to get started. b. The elevation of the heat source must be above that of the heat sink.
c. The driving force is a difference in density. d. Heat transfer is more efficient if steam is mixed with water.

Answer: A.01 c.

Reference:

General Physics, HT&FF, pp. 355 - 358

Question A.002 (1.0 point) {2.0} Which one of the following is the reason for operating with thermal neutrons instead of fast neutrons?

a. Neutron absorption in non-fuel material increases exponentially as neutron energy increases.
b. Doppler and moderator temperature coefficients become positive as neutron energy increases.
c. The fission cross section of the fuel is much higher for thermal energy neutrons than fast neutrons.
d. Increased neutron efficiency since thermal neutrons are less likely to leak out of the core than fast neutrons.

Answer: A.02 c.

Reference:

Nuclear Energy Training, Module 3, 1.5-2 and 2.6-1.

Question A.003 (1.0 point) {3.0} Which one of the following is the definition for INTEGRAL ROD WORTH? Integral Rod Worth is defined as the reactivity:

a. due to control rod position. b. change per unit of rod motion.
c. due to the difference in a control rods position.
d. still available for shutdown after control rod withdrawal.

Answer: A.03 a.

Reference:

Nuclear Energy Training Module 3 Section 7 page 7.5-1

Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question A.004 (1.0 point) {4.0} Given the associated graph, which of the following answers best describe the neutron behavior within Region II?

a. The neutron cross section is inversely proportional to the neutron velocity (1/V)
b. The neutron cross section decreases steadily with increasing neutron energy (1/E).
c. Neutrons of specific energy levels (e.g., 50 ev, 100 kev) have a greater potential for leakage from the reactor core
d. Neutrons of specific energy levels (e.g., 50 ev, 100 kev) are more likely to be readily absorbed than neutrons at other energy levels.

Answer: A.04 d.

Reference:

DOE Fundamentals Handbook Nuclear Physics and Reactor Theory Vol. 2

Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question A.005 (1.0 point) {5.0} Regulating rod worth for a reactor is 0.001 K/K/inch. Moderator temperature increases by 9ºF, and the regulating rod moves 41/2 inches inward to compensate. The moderator temperature coefficient Tmod is -

a. +5 x 10

-4 b. -5 x 10

-4 c. +2 x 10

-5 d. -2 x 10

-5 Answer: A.05 a.

Reference:

OSU Training Manual Vol. 3, p. 19 Also, (4.5 x 0.001) ÷ 9 = 0.0045 ÷ 9 = 0.0005 = 5 x 10

-4

Question A.006 (1.0 point) {6.0} Which ONE of the following describes the MAJOR contributor to the production and depletion of Xenon respectively in a STEADY-STATE OPERATING reactor?

Production Depletion

a. Radioactive decay of Iodine and Tellurium Radioactive Decay b. Radioactive decay of Iodine and Tellurium Neutron Absorption c. Directly from fission Radioactive Decay d. Directly from fission Neutron Absorption

Answer: A.06 b.

Reference:

Oregon State University Training Manual Volume 3, Reactor Operation and Xenon Poisoning, p. 22, 1 st ¶.

Question A.007 (1.0 point) {7.0} Which one of the following is the description of a thermal neutron?

a. A neutron possessing thermal rather than kinetic energy.
b. The primary source of thermal energy increase in the reactor coolant during reactor operation.
c. A neutron that experiences no net change in energy after several collisions with atoms of the diffusing media.
d. A neutron that has been produced in a significant time (on the order of seconds) after its initiating fission took place.

Answer: A.07 c.

Reference:

Generic

Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question A.008 (1.0 point) {8.0} Which one of the following reactions describes how 7Nitrogen16 is produced? 7 Oxygen 16:

a. absorbes a neutron then decays by proton emition. b. decays by neutron emition then absorbes a proton
c. absorbes a proton then decays by neutron emition
d. decays by a proton emition then absorbes a neutron Answer: A.08 a.

Reference:

Chart of the Nuclides

Question A.009 (1.0 point) {9.0} Given the following Primary System Parameters. Reactor Pool Volume 14,250 gals Reactor Pool Temperature 104 F Reactor Power Level 1 MW

Which one of the following is the amount of time that is available before the reactor is scrammed, at 118 F pool temperature, when primary coolant flow is lost?

a. 15 minutes b. 22 minutes c. 29 minutes d. 36 minutes

Answer: A.09 c.

Reference:

Question A.010 (1.0 point) {10.0} The number of neutrons passing through a square centimeter per second is the definition of which ONE of the following?

a. Neutron Population (np) b. Neutron Impact Potential (nip) c. Neutron Flux (nv) d. Neutron Density (nd)

Answer: A.10 c.

Reference:

DOE Fundamentals Handbook, Nuclear Physics and Reactor Theory

Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question A.011 (1.0 point) {11.0}

The Fast Fission Factor () is defined as "The ratio of the number of neutrons produced by - a. fast fission to the number produced by thermal fission. b. thermal fission to the number produced by fast fission.

c. fast and thermal fission to the number produced by thermal fission. d. fast fission to the number produced by fast and thermal fission.

Answer: A.11 c.

Reference:

NEEP 234, p. 89.

Question A.012 (1.0 point) {12.0} Which statement illustrates a characteristic of Subcritical Multiplication? a. The number of source neutrons decreases for each generation.

b. The number of fission neutrons remain constant for each generation. c. The number of neutrons gained per generation gets larger for each succeeding generation. d. As Keff approaches unity (1), for the same increase in Keff, a greater increase in neutron population occurs.

Answer: A.12 d.

Reference:

Nuclear Training Manual

Question A.013 (1.0 point) {13.0} The purpose of the installed neutron source is to: a. Compensate for neutrons absorbed in non-fuel materials in the core. b. Provide a means to allow reactivity changes to occur in a subcritical reactor.

c. Generate a sufficient neutron population to start the fission chain reaction for each startup. d. Generate a detectable neutron source level for monitoring reactivity changes in a shutdown reactor.

Answer: A.13 d.

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, © 1982, Page 4-21.

Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question A.014 (1.0 point) {14.0} During a fuel loading of the core, as the reactor approaches criticality, the value of 1/M: a. Increases toward one b. Decreases toward one

c. Increases toward infinity d. Decreases toward zero

Answer: A.14 d.

Reference:

R. R. Burn, Introduction to Nuclear Reactor Operations, pg. 5-18

Question A.015 (1.0 point) {15.0} Which ONE of the following is the definition of the term "Cross-Section?" a. The probability that a neutron will be captured by a nucleus.

b. The most likely energy at which a charge particle will be captured. c. The length a charged particle travels past the nucleus before being captured. d. The area of the nucleus including the electron cloud.

Answer: A.15 a

Reference:

Burn, R., Introduction to Nuclear Reactor Operations, © 1982

Question A.016 (1.0 point) {16.0} Which ONE of the following coefficients will be the first one to start turning reactor power after a power

excursion?

a. Moderator Coefficient b. Void Coefficient
c. Doppler Coefficient d. Poisons buildup

Answer: A.16 c.

Reference:

DOE Fundamentals Handbook Nuclear Physics and Reactor Theory Vol. 2

Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question A.017 (1.0 point) {17.0}

Why does the fuel temperature (Doppler) coefficient becomes less negative at higher fuel temperatures?

a. As reactor power increases, the rate of increase in the fuel temperature diminishes.
b. Neutrons penetrate deeper into the fuel, resulting in an increase in the fast fission factor.
c. The amount of self-shielding increases, resulting in less neutron absorption by the inner fuel.
d. The broadening of the resonance peaks diminishes per degree change in fuel temperature.

Answer: A.17 d.

Reference:

FNRE pg. 146, 149

Question A.018 (1.0 point) {18.0}

When performing rod calibrations, many facilities pull the rod out a given increment, then measure the time for reactor power to double (doubling time), then calculate the reactor period. If the doubling time is 42 seconds, what is the reactor period?

a. 29 sec b. 42 sec c. 61 sec d. 84 sec

Answer: A.18 c.

Reference:

ln (2) = -time/ = time/(ln(2)) = 60.59 approx. 61 seconds

Question A.019 (1.0 point) {19.0} INELASTIC SCATTERING is the process by which a neutron collides with a nucleus and - a. recoils with the same kinetic energy it had prior to the collision.

b. is absorbed, with the nucleus emitting a gamma ray, and the neutron with a lower kinetic energy.
c. is absorbed, with the nucleus emitting a gamma ray.
d. recoils with a higher kinetic energy than it had prior to the collision with the nucleus emitting a gamma ray.

Answer: A.19 b.

Reference:

R. R. Burn, Introduction to Nuclear Reactor Operations, pg. 2-28

Section A: Reactor Theory, Thermodynamics, and Fac. Operating Characteristics Question A.020 (1.0 point) {20.0} The reactor supervisor tells you that the K eff for the reactor is 0.955. How much reactivity must you add to the reactor to reach criticality?

a. +0.0471 b. +0.0450
c. -0.0471
d. -0.0450 Answer: A.20 a

Reference:

= (K eff1 - K eff2) ÷ (K eff1

  • K eff2) = (0.9550 - 1.0000) ÷ (0.9550
  • 1.0000)

= -0.0450 ÷ 0.9550 = -0.0471

Section B: Normal/Emergency Procedures&RadiologicalControls Question B.001 [1.0 point] {1.0} To release the fuel element, from the flexible handling tool, it is necessary to

_______________.

a. pull the handle out approximately 1 inch. b. push the handle in approximately 2 inches. c. pull the handle out approximately 3 inches. d. pull the handle out approximately 6 inches.

Answer: B.01 a.

Reference:

OSTROP 11, Fuel Element Handling Procedure

Question B.002 [1.0 point] {2.0} To maintain an active operator license, 10CFR55 requires "the licensee shall perform the functions of an operator or senior operator for a minimum of ___ hours per calendar quarter".

a. 2 b. 4
c. 6 d. 8 Answer: B.02 b.

Reference:

10CFR55.53(e) last sentence.

Question B.003 [1.0 point] {3.0} A small experiment sample reads 200 mR/hr with the sample 1 foot under water and the meter at the surface of the water. A reading taken 1/2 hour ago with both the sample and the meter in the same positions was 400 mR/hr. Approximately how long will it take for the reading to drop to 20 mR/hr with the sample and the meter in the same positions?

a. 40 minutes b. 70 minutes
c. 100 minutes
d. 130 minutes Answer: B.03 c.

Reference:

A = A0 e

-t Solve for 200 = 400 e

-30minutes ln (200/400) = -x 30minutes ln(1/2)/30 minutes = - = 0.0231 Next solve for time 20 = 200 e(-0.0231 x time) ln (1/10)/-0.0231 = time = 99.7 minutes or approximately 100 minutes

Section B: Normal/Emergency Procedures&RadiologicalControls Question B.004 [1.0 point] {4.0} Which one of the following ranges is used for the area radiation monitors (ARMs) at OSTR? a. 0.1 mR/hr - 10 R/hr

b. 1 mR/hr - 10 R/hr
c. 10 mR/hr - 20 R/hr
d. 20 mR/hr - 10 R/hr Answer: B.04 a.

Reference:

EP 7.1.2

Question B.005 [1.0 point] {5.0} You note that 1 cm of a material (used as a shield) reduces the radiation level from a given source by a factor of 2. If you add another nine cm of the material (for a total of 10 cm), you would expect the radiation level to be reduced by a factor of approximately ____ over no shielding. (Note: Ignore dose decrease due to distance, and decay.)

a. 20 b. 100 c. 200 d. 1,000 Answer: B.05 d.

Reference:

2 10 = 1,024 approximately equals 1,000

Question B.006 [1.0 point, 0.333 each] {6.0} Identify the source for the listed radioisotopes. Irradiation of air , water, or fission product (FP). a. N 16 b. Ar 41 c. Xe 188 Answer: B.06 a. = water; b. = air; c. = FP

Reference:

Standard NRC question

Section B: Normal/Emergency Procedures&RadiologicalControls Question B.007 [1.0 point, 0.25 each] {7.0} Identify each of the following as either a Safety Limit (SL), a Limiting Safety System Setting (LSSS) or a Limiting Condition for Operation (LCO)

a. The temperature in a TRIGA fuel element shall not exceed 2100ºF (1150ºC) under any conditions of operation.
b. - shall be 510ºC (950ºF) as measured in an instrumented fuel element.
c. The shutdown margin provided by control rods shall be greater than $0.55 with: experimental facilities, and experiments in place and the highest worth non-secured experiment in its most reactive state, the most reactive control rod fully withdrawn, and the reactor in the cold condition without xenon.
d. The reactor shall not be operated if: The pool water bulk temperature exceeds 120ºF (49ºC).

Answer: B.07 a. = SL; b. = LSSS; c. = LCO; d. = LCO

Reference:

Technical Specifications §§ 2.1, 2.2, 3.2 and 3.7.2

Question B.008 [1.0 points, 0.25 each] {8.0} Identify each of the following as either a Channel Check , a Channel Test or a Channel Calibration.

a. Dipping a temperature detector in ice water and verifying the channel reads 32ºF (0ºF) b. Verifying proper overlap between Nuclear Instrumentation Channels during startup. c. After receiving an alarm on an Area Radiation Monitor, you verify the reading with a hand-held meter.
d. Performing a reactor pool water rate-of-temperature-rise measurement, then adjusting the detectors to correct readout.

Answer: B.08 a. = test; b. = check; c. = check; d. = cal

Reference:

Technical Specifications §§ 1.31, 1.32 and 1.33

Section B: Normal/Emergency Procedures&RadiologicalControls Question B.009 [1.0 points] {9.0} Which ONE of the following is the definition of Emergency Action Level?

a. a condition that calls for immediate action, beyond the scope of normal operating procedures, to avoid an accident or to mitigate the consequences of one.
b. Specific instrument readings, or observations; radiation dose or dose rates; or specific contamination levels of airborne, waterborne, or surface-deposited radioactive materials that may be used as thresholds for establishing emergency classes and initiating appropriate emergency methods.
c. classes of accidents grouped by severity level for which predetermined emergency measures should be taken or considered.
d. a document that provides the basis for actions to cope with an emergency. It outlines the objectives to be met by the emergency procedures and defines the authority and responsibilities to achieve such objectives.

Answer: B.09 b

Reference:

Emergency Plan, § 2.0 Definitions, p. 2-1.

Question B.010 [1.0 points] {10.0} Which ONE of the following Emergency classifications is NOT used at the Oregon State University TRIGA reactor?

a. Personnel and Operational Event b. Notification of Unusual Event c. Alert d. Site Area Emergency Answer: B.10 d.

Reference:

Emergency Plan §4.0 Emergency Classification System pp. 4 4-4.

Question B.011 [1.0 points] {11.0} According to Technical Specification 3.8.a, N on-secured experiments s hall have a reactivity worth less than ___ .

a. <$.25 b. <$.50 c. <$.75 d. <$1.0 Answer: B.11 d.

Reference:

Technical Specification 3.8.1.a

Section B: Normal/Emergency Procedures&RadiologicalControls Question B.012 [1.0 points, 0.25 each] {12.0} For each event listed, identify the appropriate action the console operator shall take (according to OSTROP 1, Emergency Operating Procedures) as either SHUTDOWN (SD) the reactor or SCRAM the reactor. Assume the condition(s) has been verified.

a. Stack gas high activity. b. Stack monitor pump off.
c. Stack monitor filter failure.
d. Stack particulate high activity.

Answer: B.12 a. =

scram; b. = SD; c. = SD; d. = scram

Reference:

OSTROP 1, Emergency Operating Procedures

Question B.013 [1.0 points] {13.0} The CURIE content of a radioactive source is a measure of a. the number of radioactive atoms in the source. b. the amount of energy emitted per unit time by the source c. the amount of damage to soft body tissue per unit time. d. the number of nuclear disintegrations per unit time.

Answer: B.13 d.

Reference:

Standard NRC definition

Question B.014 [1.0 points, 0.25 each] {14.0} Match the radiation reading from column A with its corresponding radiation area classification (per 10 CFR 20) listed in column B.

COLUMN A COLUMN B

a. 10 mRem/hr 1. Unrestricted Area
b. 150 mRem/hr 2. Radiation Area c. 10 Rem/hr 3. High Radiation Area d. 550 Rem/hr 4. Very High Radiation Area Answer: B.14 a. = 2; b. = 3; c. = 3; d. = 4

Reference:

10 CFR 20.1003, Definitions

Section B: Normal/Emergency Procedures&RadiologicalControls Question B.015 [1.0 points] {15.0} Which ONE of the following is the maximum number of times the reactor may be pulsed in a one hour period WITHOUT Reactor Supervisor permission?

a. Three b. Six c. Nine d. Twelve Answer: B.15 b.

Reference:

OSTROP 4, Reactor Operation Procedures, VII. Repetitive Pulsing

Question B.016 [1.0 points] {16.0} Technical Specification 5.4 requires "all fuel and fueled devices not in the core shall be stored in such a way that K eff is less than -

a. 0.80 b. 0.85
c. 0.90 d. 0.95 Answer: B.16 c.

Reference:

Technical Specification 5.5, p. 27

Question B.017 [1.0 points] {17.0} Which ONE of the following conditions is a Reportable Occurrence per Technical Specifications?

a. Irradiation of a sample containing 20 milligrams of explosive material. b. Operation of the reactor with a fuel temperature scram set at 500ºC. c. Operation of the reactor with bulk water temperature at 45ºC. d. Operation with pool water level 13 feet above the core.

Answer: B.17 d.

Reference:

Technical Specifications, 2.2, 3.3.a, 3.6.d and 3.2.2 (Table 2)

Section B: Normal/Emergency Procedures&RadiologicalControls Question B.018 [1.0 points] {18.0} An individual receives 100 mRem of Beta (), 25 mRem of gamma (), and 5 mRem of neutron radiation. What is his/her total dose?

a. 275 mRem b. 205 mRem c. 175 mRem d. 130 mRem Answer: B.18 d.

Reference:

10 CFR 20.4 A rem is a rem is a rem

Question B.019 [1.0 points] {19.0} Which ONE of the following is the Technical Specification BASIS for the Limiting Condition of Operation for pool water temperature being maintained below 120°F?

a. To prevent damage to the resin in the purification system. b. To prevent cavitation in the primary coolant pump.
c. To maintain the integrity of the Aluminum Reactor Tank. d. to ensure correct operation of the conductivity cells in the purification system.

Answer B.19 c.

Reference:

Technical Specification 3.3

Question B.020 [1.0 point] {20.0} Which ONE of the following statements concerning emergency exposure limits is correct? "For lifesaving situations, a total effective dose of up to is permissible without authorization, due to the implied urgency of the situation".

a. 5 rem b. 10 rem c. 25 rem d. 50 rem Answer: B.20 c.

Reference:

Emergency Plan § 7.4.1

Section C: Facility andRadiation MonitoringSystems Question C.001 [1.0 point, 0.17 each] {1.0} Match the detector type in column B with the proper reactor channel in column A. (Note items from column B may be used more than once, or not at all.)

Column A Column B

a. Linear Channel 1. Fission Chamber b. Log-N Channel 2. BF 3 Counter c. Period Channel 3. Compensated Ion Chamber d. Safety Channel 4. Uncompensated Ion Chamber e. Percent Power Channel 5. Cherenkov Detector f. nv circuit Channel Answer: C.01 a. = 1; b. = 1; c = 1 d. = 4; e. = 4; f. = 4

Reference:

OSU Trn Man Volume 2, § IV OSTR Neutron Detection Channels Question C.002 [1.0 point] {2.0} Which ONE of the following is the reason that primary temperature is maintained below 120ºF?

Above this temperature the ...

a. purification system filter melts. b. demineralizer resin rate of depletion increases. c. diffusion of N 16 from the pool increases dramatically. d. bath temperature coefficient changes from negative to positive.

Answer: C.02 b.

Reference:

OSU Trn Man Volume 1, Reactor Water Systems Question C.003 [1.0 point] {3.0} Which ONE of the valve lineups listed below will result in sending a "rabbit" INTO the core? (Use drawing provided with handout.)

OPEN SHUT a. 1 & 2 3 & 4 b. 3 & 4 1 & 2 c. 1 & 3 2 & 4 d. 2 & 4 1 & 3 Answer: C.03 c.

Reference:

OSTR Training Manual, Vol I, fig. 1.40 Standard Rabbit System Schematic

Section C: Facility andRadiation MonitoringSystems Question C.004 [1.0 point, 0.33 each] {4.0} Match the throttling valve listed in column A with the parameter (pressure of flow rate) that it is set to maintain. Use the drawing of the Primary and Purification Systems provided for Reference.

Valve Parameter Maintained

a. DV-16 1. ~50psig b. PV-6 2. ~10gpm c. PV-7 3. ~ 50 gpm 4. ~ 440 gpm Answer: C.04 a. = 2; b. = 4; c. = 3;

Reference:

OSTROP 7 Operating Procedcures for Reactor Water Systems

Section C: Facility andRadiation MonitoringSystems

Section C: Facility andRadiation MonitoringSystems Question C.005 [1.0 point] {5.0} Which ONE of the following is the actual method used to determine standard control rod position from fully inserted to fully withdrawn?

a. A logic circuit receives input from two sensors which count 100 pulses per revolution along with detecting direction, converting these signals to rod position.
b. As the rod moves up and down, the magnet opens and closes a series of 100s of limits switches which generate a signal which is converted to rod position.
c. A potentiometer, driven by the rod drive motor, generates a signal proportional to rod position.
d. As the rod moves, it moves into or out of a coil, generating a signal proportional to rod position.

Answer: C.05 c.

Reference:

OSU Trn Man Volume 1, Control Rod Drives, Question C.006 [1.0 point] {6.0} Which ONE of the following is the main function performed by the DISCRIMINATOR circuit in the startup channel? a. To generate a current signal equal and of opposite polarity as the signal due to gammas generated within the Log-N Channel Detector.

b. To filter out small pulses due to gamma interactions, passing only pulses due to neutron events within the Log-N Channel Detector.
c. To convert the linear output of the Log-N Channel Detector to a logarithmic signal for metering purposes.
d. To convert the logarithmic output of the metering circuit to a 5t (differential time) output for period metering purposes.

Answer: C.06 b.

Reference:

OSTR Training Manual Vol. 2, § IIIA, page 13.

Section C: Facility andRadiation MonitoringSystems Question C.007 [1.0 point] {7.0} Flow through the demineralizer loop is limited to 10 gallons per minute. This limit is to prevent a. blowing resin out of the demineralizer thereby clogging the filter. b. creating channels through the demineralizer reducing efficiency. c. blowing the upstream filter into the demineralizer. d. overpressurization of the demineralizer.

Answer: C.07 b.

Reference:

OSU Trn Man Volume 1, Demineralizer, p. 116.

Question C.008 [1.0 point] {8.0} Match the control rod drive mechanism part from column "A" with the correct function in column "B".

COLUMN A COLUMN B

a. Piston 1. Provide rod bottom indication. b. Potentiometer 2. Provide rod full withdrawn indication. c. Spring-loaded Pull Rod 3. Works with dash pot to slow rod near bottom of its travel. d. Push Rod 4. Provide rod position indication when the electromagnet engages the armature.

Answer: C.08 a. = 3; b. = 4; c. = 1; d. = 2

Reference:

Chapter 1, General Description of TRIGA Research Reactor Question C.009 [1.0 point] {9.0} A sample placed in which ONE of the following experimental facilities can be modified to supply a highly collimated beam of neutron and gamma radiation?

a. Lazy Susan b. Central Thimble c. Hollow Element Assembly d. Pneumatic Transfer system Answer: C.09 b.

Reference:

OSU Trn Man Volume 1, Central Thimble, p. 89.

Section C: Facility andRadiation MonitoringSystems Question C.010 [1.0 point] {10.0} The purpose of the graphite slugs located at the top and bottom of each fuel rod is to... a. reflect neutrons, thereby reducing neutron leakage from the core. b. absorb neutrons, thereby reducing neutron leakage from the core. c. couple neutrons from the core to the nuclear instrumentation, decreasing shadowing effects. d. absorb neutrons, thereby reducing neutron embrittlement of the upper and lower guide plates.

Answer: C.10 a.

Reference:

OSU Trn Man Volume 1, Fuel-Moderator Elements Question C.011 [1.0 point] {11.0} The ventilation system contains a static regulator which modulates a static pressure damper to maintain the reactor bay pressure at a ...

a. higher pressure than the Radiation center building. b. higher pressure than the outside atmosphere. c. lower pressure than the outside atmosphere. d. pressure equal to atmospheric pressure.

Answer: C.11 c.

Reference:

OSU Trn Man Volume 1, Reactor Bay Exhaust Fan, pp. 146 - 148.

Question C.012 [1.0 point] {12.0}

Which ONE of the following parameters is NOT measured in the Primary Cooling/Purification System Loops? a. Temperature b. Conductivity c. Flow Rate d. pH Answer: C.12 d.

Reference:

OSU Trn Man Volume 1, Reactor Water Systems, pp. 106 - 120.

Section C: Facility andRadiation MonitoringSystems Question C.013 [1.0 point] {14.0} What design feature minimizes flux peaking in the central thimble. a. An aluminum plug. b. A Zirconium plug. c. A cadmium plug. d. Filling with N

2. Answer: C.13 a.

Reference:

OSU Training Manual Vol I, p, 89 second paragraph.

Question C.014 [1.0 point] {14.0} Which ONE of the listed Nuclear Instrumentation Channels/circuits listed below does NOT provide an input to the Regulating Rod Automatic Control Circuit.

a. Log-N b. Linear Power c. Percent Power d. Percent Demand Answer: C.14 c.

Reference:

ORST Trn Man Volume II, Figure 2.16 Question C.015 [1.0 points, 0.25 each] {15.0} The core is shielded radially by (a) of graphite reflector, (b) of lead (inside the reflector can), (c) of water, and (d) of concrete. For the shielding items identified a - d in the question and listed in Column A chose the correct dimension from the items in Column B. Items in Column B may or may not be used.

Column A Column B

a. graphite reflector. 2 inches b. lead. 8 inches
c. water. 1.5 feet d. concrete. 8 feet 15 feet Answer: C.15 a. = 8"; b. = 2"; c. = 1.5'; d. = 8'

Reference:

ORST Trn Man Volume I, Reactor Description

Section C: Facility andRadiation MonitoringSystems Question C.016 [1.0 point] {16.0} Which ONE of the following is NOT an interlock associated with pulsing operations. a. Period greater than 50 seconds. b. Transient Rod fully inserted. c. Power less than 1 Kwatt. d. Switch in Pulse Mode.

Answer: C.16 a.

Reference:

Volume 2, pages 23-28, OSU Triga Manual Question C.017 [1.0 point] {17.0} Which ONE of the following electrical loads is NOT powered by the Emergency Generator or inverter batteries on a loss of site power?

a. Argon Fan b. Cypher Lock c. Television Monitor d. Stack Monitor Pump Answer: C.17 a.

Reference:

OSTROP 22 Question C.018 [1.0 point] {18.0} Primary system water returning to the pool is ejected from an angled nozzle, causing a swirling motion of the water in the pool. Which ONE of the following is the PRIMARY purpose for this design?

a. To increase the heat transfer rate due to increased convective flow. b. To decrease the activation rate of O 16 to N 16 due to a decrease in time within the core. c. To increase the transport time for N 16 to reach the surface of the pool. d. To break up O 16 bubbles in the pool thereby decreasing the production of N
16. Answer: C.18 c.

Reference:

OSTR Training Manual Vol. I Reactor Water Systems, fig. 1.6.

Section C: Facility andRadiation MonitoringSystems Question C.019 [1.0 point, 0.25 each] {19.0} Identify each of the control rods as having either a fuel follower or an air follower. a. Shim b. Safety c. Transient d. Regulating Answer: C.19 a. = Fuel; b. = Fuel; c = Air; d.= Fuel

Reference:

Volume 1, pages 40-44, OSU Triga Manual Question C.020 [1.0 point] {20.0} The ventilation system is designed to maintain reactor bay pressure slightly negative pressure with respect to the atmospheric pressure. If the outside atmospheric pressure increases, which ONE of the following actions will automatically occur to compensate the reactor bay pressure? A pressure regulator will generate a signal to ...

a. Increase the Reactor Bay Supply fan speed to increase bay pressure. b. Decrease the Reactor Bay Exhaust fan speed to increase bay pressure. c. Go more open on a damper in the ventilation supply ducting increasing bay pressure. d. Go more closed on a damper in the ventilation exhaust ducting increasing bay pressure.

Answer: C.20 d.

Reference:

OSTR Training Manual, Vol. I p. 148.