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Updated: November 2015
TJ van Rooyen
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Areas of expertise & problem-solving abilities .................................................................. 3
Core competencies ..................................................................................................... 3
Abbreviations ........................................................................................................... 5
Personal details ......................................................................................................... 6
Tertiary Education ..................................................................................................... 7
Experience: Brief Overview ......................................................................................... 7
Experience: Detailed Overview ..................................................................................... 9
Membership of professional societies ........................................................................... 14
Selected Publications ................................................................................................ 16
Other publications and contributions............................................................................. 23
Lecturing activities................................................................................................... 23
Postgraduates led to M.Sc. degrees: 1999 – present .......................................................... 25
References ............................................................................................................. 26
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Johann van Rooyen - Engineering Scientist:
Nuclear Criticality Safety
Areas of expertise & problem-solving
abilities -- core competencies
1. Nuclear Reactor Scientist; Radiation Shielding Scientist;
Nuclear Criticality Safety Scientist.
2. The use of the Radiation Transport, Shielding & Criticality
codes MCNP6, SCALE to solve problems in the field of
nuclear reactor science, the shielding of ionising radiation,
and nuclear criticality safety.
3. Pre-Graduate and Postgraduate Education in the fields of
Mathematical Science, Physical Science, Nuclear Physics,
Nuclear Engineering, Radiation Shielding, and Nuclear
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4. Guiding postgraduates in MSc projects in the fields of
radiation shielding, nuclear criticality safety, and nuclear
5. Basic programming skills in Fortran 95; MathCAD used as
main computational tool.
6. Radiation Protection – vast experience from past projects
and job responsibilities. Theoretical & practical experience
in this field.
7. Studying almost any technical topic, mastering it &
production of associated operational software,
recommendations, technical reports & training material --
textbook, slideshows, syllabus, etc.
8. Scientific programming in Fortran-95. Use of MathCAD
for peripheral computations and mathematical modeling.
9. Writing & proofreading skills.
10. SARPA Accredited RP specialist in (1) Nuclear Reactor
Radiation Protection, (2) Cyclotron Radiation Protection
and (3) Radionuclide Radiation Protection.
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CARST Centre for Applied Radiation Science and Technology (at NWU)
KNPS Koeberg Nuclear Power Station
NECSA South African Nuclear Energy Corporation
NORM Normally Occurring Radioactive Material
NNR National Nuclear Regulator
NRF National Research Foundation
QA Quality Assurance
RP Radiation Protection
RPD RP Division
SA South Africa
SAQA South African Qualifications Authority
SARPA Southern African Radiation Protection Association
SARPS South African Radiation Protection Society
SGB Standards Generating Body
TENORM Technologically Enhanced Normally Occurring Radioactive Material
NWU Northwest University
UCT University of Cape Town
UNAM University of Namibia
US University of Stellenbosch
UWC University of the Western Cape (Bellville)
WITS University of the Witwatersrand
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Full Name: Theunis Johann van Rooyen
Date of birth: 15 August 1958
ID-number: 580815 5145 080
Citizenship: South African
PO Box 1288
Radiation and Reactor Theory Section
Necsa (South African Nuclear Energy Corporation)
PO Box 582
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B.Sc. (Physics, Mathematics & Chemistry), University of Stellenbosch. Average
B.Sc. Honours (Physics), University of Stellenbosch. Average mark: 70%.
MSc in Nuclear Reactor Science, PotchefstroomUniversity (part-time, while
working at Atomic Energy Corporation of South Africa1 and the utility ESKOM).
Subject of thesis: The Optimisation of Radiation Shielding inside and Outside a
Nuclear Reactor. Mark: Cum Laude.
2009 -- 2011:
MSc Nuclear Engineering. NorthWest University (PotchefstroomCampus).
Completed and passed 9 theoretical modules with marks ranging between 55% and
Experience: Brief Overview
Atomic Energy Corporation of South Africa (AEC), Pelindaba.
Radiation shielding design projects.
1 Today: NECSA – Nuclear Energy Corporation of South Africa.
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ESKOM, Megawatt Park, Gauteng, South Africa.
Radiation shielding calculations;
Nuclear Criticality safety calculations
…in support of the safe operation of the Koeberg Nuclear Power Station, SA.
iThemba LABS2, Somerset West. (Situated near Somerset West, Western Cape,
South Africa. Cyclotron, radionuclide production, radiotherapy, materials research &
training centre; national facility.)
Radiation Protection Physicist. September 1990 – June 1997.
Acting manager: Radiation Protection Division. Facility Radiation Protection
Officer (RPO). July 1997 – June 1998.
Manager: Radiation Protection Division; Facility RPO. June 1998 – December
Radiation Protection Specialist. January 2003 – October 2006.
2 Formerly: National Accelerator Centre (NAC).
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November 2006-- present
Radiation and Reactor Theory (RRT) Section, Necsa (South African Nuclear Energy
1. Chief scientist: Radiation Shielding & Nuclear Ctiticality Safety. Trainer of all
new staff in specialised knowledge and expertise appointed in the above
division. Manager of Staff Training Subsection in Necsa RRT.
Experience: Detailed Overview
Employer: Atomic Energy Corporation of South Africa.
Positions: Scientist-in-training, Scientist and Senior Scientist.
Responsibilities: Radiation shield design projects.
1. Employ the discrete ordinates radiation transport codes ANISN and DOT-3.5 as
well as point kernel codes PELSHIE and QAD-CG in many neutron/photon
shielding and neutron moderator design projects. The more notable of these
2. Post-LOCA (“Loss of Coolant Accident”) dose rate determination throughout
Koeberg PWR plant; study performed in collaboration with nuclear engineers
from USA & UK.
3. Shield design of Pelindaba’s Neutron Radiography Facility.
4. The design of the local shielding around the radionuclide production target
bombardment station at the National Accelerator Centre (NAC) 3, in
collaboration with NAC staff.
5. The design of optimal moderator configurations for the moderation of neutrons
from various neutron sources, with the aim of maximizing activation of an
6. Shield design for a neutron transmutation doping facility.
7. Reactor coolant and PWR steam generator shielding studies.
3 Today: iThemba LABS.
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8. Several neutron activation safety studies.
9. Several radionuclide shielding projects, e.g. facets of HEPRO 60Co irradiator
10. Nuclear reactor shielding optimisation studies.
11. The development of several pre-processor and post-processor codes to function
with major radiation transport codes such as ANISN and DOT.
1. Nuclear Reactor Science training course. The 15 theoretical modules were
presented during 1986 by the Reactor Theory Division of the AEC (Cum
2. Management development & technical report writing courses (1987-1988).
Reasons for leaving AEC
Better remuneration offer from ESKOM enabled me to move from a small 1½-
bedroomed flat to a 3-bedroomed house, with wife & first baby.
Employer: ESKOM (Megawatt Park, Gauteng, South Africa).
Position: Professional Physicist.
Radiation shielding calculations
Criticality calculations for nuclear fuel.
Information Technology equipment procurement & technical support.
1. Used discrete ordinates radiation transport codes (such as ANISN and DOT) as
well as point kernel codes (e.g. QAD-CG) in several Koeberg-related radiation
shielding design projects. Also used the SCALE system to perform criticality,
shielding and reactor fuel radionuclide inventory analyses. The more notable of
these projects include:
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2. Pressurised nuclear reactor spent-fuel storage pool water level accident scenario
analysis – nuclear power station blackout scenario. Calculation of increasing
dose rates as water level of spent-fuel storage pool drops as a result of boiling
after SFP cooling system pumps fail.
3. Spent fuel transport flask criticality analysis.
4. Reactor fuel radionuclide inventory calculations with ORIGEN-S.
5. Computer code development using Fortran.
6. Development of procedures.
7. Training of Koeberg staff in IBM MVS Job Control Language for Mainframe
computer systems. Developed a comprehensive, 220-page manual for this
8. Training of Council for Nuclear Safety (CNS4) personnel in the use of the
shielding code QAD-CG.
9. Reactor shielding benchmark calculations.
10. Nuclear reactor shielding optimisation studies. Complete M.Sc. on this topic
1. Koeberg radiation safety training course.
2. Nuclear reactor theory course.
3. Selections from Koeberg's Nuclear Energy Training course.
4. Courses and symposia at the Council for Nuclear Safety5.
5. Several ESKOM management development courses.
Reasons for leaving ESKOM
1. Preference for specialised, technical work. Did not want to be burdened with
excessive management work at age of circa 30, because that would have
adversely affected my technical core competencies;
4 Today: National Nuclear Regulator (NNR).
5 Today: National Nuclear Regulator (NNR).
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2. Strong dislike of Megawatt Park’s open floor plan office layout. Need privacy
to concentrate, think deeply, and perform mathematical modeling.
September 1990 — October 2006
iThemba LABS, PO Box 722, Somerset West, 7129, South Africa.
1. Radiation Protection Physicist. September 1990 – June 1997.
2. Acting head: Radiation Protection Division & Radiation Protection Officer
(RPO). July 1997 – June 1999.
3. Head: Radiation Protection Division; Facility Radiation Protection Officer.
June 1999 – December 2002.
4. Radiation Protection Specialist. January 2003 – present.
1. Radiation Safety training. Development of course material & presentation of
monthly courses. Provide a Radiation Protection Training and Reference
Manual to facility.
2. Radiation shielding calculations.
3. Developed and teach postgraduate course in Radiological Protection at
University of Stellenbosch.
4. Developed and teach postgraduate courses in Radiological Protection at
Northwest University (NWU).
5. Taught postgraduate course in Radiological Protection at University of the
Western Cape (UWC).
6. Radiation Protection development work at facility.
7. Liaison with regulatory authorities.
8. Guidance of postgraduates in MSc projects in RP.
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9. Conceptual design of automated measurement systems that continually verify
whether key Operating Technical Specifications (OTS) are met.
10. Compile report on effect of ionising radiation on electronics apparatus, and
write computer code to determine lifetimes on electronic equipment types in
11. Study current best international RP practice from ICRP, NCRP, IAEA, IRPA,
CFR & NRPB publications. Study RP legislation and regulations. Study RP
journals. Keep abreast of international developments in RP philosophy and
practice. Translate all these into concrete RP policies, training material, written
safe working procedures (WSWPs), notices for posting, circulars and RP
directives—suitably adapted to our institution.
12. Practical radiation work & supervision of dangerous radiation work.
13. Represent iThemba LABS at SARPA and SARPS professional RP societies.
14. Serve on Standards Generating Body (SGB) for RP as part of South African
Qualifications Authority (SAQA) programme.
15. Visit to Ghana in April 2006 as Technical Expert on Dose Rate Calculations &
Radiation Shielding Design.
November 2006 -- present
Radiation and Reactor Theory Section, Necsa (South African Nuclear Energy
1. Chief scientist: Radiation Shielding & Nuclear Criticality Safety.
2. Manager: Staff Development and Training in Necsa RRT.
1. Hundreds of specialised technical analyses and technical reports for client groups
within Necsa. Fields: Radionuclide production, Nuclear Medicine, Nuclear
Waste, Mining Radiation Dose Rates, Nuclear Fuel, Nuclear Reactor related dose
2. Presentation of in-house training courses to new technical staff with postgraduate
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3. Supervising postgraduates -- mainly from NWU, UJ & WITS -- performing
projects in nuclear radiation shielding, nuclear reactor modeling, radiation
protection in mines, and nuclear criticality safety.
4. Presentation of an annual course in Radiation Shielding Theory, and the basics of
the use of the Monte Carlo radiation transport code MCNP.
5. Lecturing at universities, as requested (average of 21 days per annum) -- WITS,
UCT, NWU, UNAM and even UTH (University Teaching Hospital) in Lusaka,
In-service training received
1. MCNP course at AEC of SA, February 1998. Duration: 5 days. (Monte Carlo
radiation transport code).
2. MCNP course, ESKOM, Megawatt Park, Gauteng. Duration: 8 days.
3. MCNP course, presented by LANL personnel. iThemba LABS. March 2006.
4. MCNP Intermediate Level Course. München, Germany. October 2008.
5. Nuclear Criticality Safety Engineering Course, University of Tennessee, USA.
6. SCALE Course, France, 2010.
7. FISPACT-2007 course, France, 2013.
8. Variety of management courses.
9. Variety of IT-related courses, e.g. ICDL course, and intermediate & Advanced
MS OFFICE courses.
10. Many RP and Nuclear Reactor Science conferences & workshops in Southern
11. Variety of ISO 9000 courses & many NOSA & NOSA-style Occupational
Health & Safety & Environment (SHEQ) courses.
Membership of professional societies
1. South African Institute for Physics (SAIP).
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2. South African Radiation Protection Association (SARPA).
3. South African Council for Natural Scientific Professions. Registration number:
Pr. Sci.Nat. 400281/87.
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VAN ROOYEN, TJ. 1987. A Calculation of the Time Dependenceof the Dose Rate
in the LargeIrradiation Facility of the Safari-1 Research Reactor due to Neutron
Activation Products Produced in the Core Box. ReportPIN-1033. Pelindaba,
Pretoria: AEC of SA. 23 p.
VAN ROOYEN, TJ. 1988. A calculation of the ambientdose equivalentrate
present during the handlingof pieces of iron flux wire irradiated in the Safari-1
Research Reactor. Report PIN-1068. Pelindaba, Pretoria: AEC of SA. 17 p.
VAN ROOYEN, TJ. 1988. Fluence Rates, Dose Rates, and HeatRelease Rates
Inside and Behind VariousThicknesses of Lead Blocks Adjacent to the Safari-1
Research Reactor. Report PIN-1106. Pelindaba, Pretoria: AEC of SA. 23 p.
VAN ROOYEN, TJ. 1989. The Design of an OptimalShield for an Intense (D-T)
Neutron Source. ReportGNS-NFCS-0004. ESKOM, Megawatt Park, Gauteng,
VAN ROOYEN, TJ. 1990. The OptimalDesign of Shielding Insideand Outside a
Nuclear Reactor. (M.Sc. thesis on shield optimisation.)
VAN ROOYEN, TJ. 1991. PRE-ANISN, a Preprocessing Code for ANISN and
other Radiation TransportCodes. Somerset West, South Africa: iThemba LABS.
(NAC Report NAC/91–06, December 1991.)
STEYN, GF;VAN ROOYEN, TJ; BINNS; PJ; HOUGH, JH; NORTIER, FM &
MILLS, SJ. 1992. Design calculations for a local radiation shield of a radioisotope
production target bombardmentstation. Nuclear Instruments and Methods in
Physics Research A316 (1992), 128 – 133.
NORTIER FM, BINNS PJ, HANEKOM J, PENNY MA, QUANTRILL RE, SMIT
HA, VAN ROOYEN TJ & XULUBANA VMP. 1999. A Second Target Station for
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Radioisotope Production at the NAC. Posterpresented at the 8th International
Workshop on Target Chemistry, St Louis, Missouri, USA, 24-27 June 1999.
NORTIER FM, BINNS PJ, HANEKOM J, PENNY MA, QUANTRILL RE, SMIT
HA, VAN ROOYEN TJ & XULUBANA VMP. 1999. A Second Target Station for
the Bombardmentof semi-permanenttargets at the NAC.
VAN ROOYEN, TJ. 1993. BUCORST, a Code to prepare Burnup-dependent
Multigroup Nuclear Reactor Source Terms. NAC ReportNAC/93-01. Somerset
West, South Africa: iThemba LABS.
VAN ROOYEN, TJ & DE BEER, GP. 1993. A Burnup-compensated Madland-Nix
prompt fission neutron source term for multigroup nuclearreactor shielding
calculations. Nuclear Science and Engineering, 114:87 – 101.
VAN ROOYEN, TJ, HURWITZ, CM, DIRKSE, JAMT, MEYER, BR &
MACKRIEL, DEG. 1996. Theanalysis of radiation doses recorded by the iThemba
LABS’Area Radiation Monitoring System (ARMS). 36th Annual Congress of the
South African Association of Physicists in Medicine and Biology, Pretoria, June
VAN ROOYEN, TJ. 1996. A point-kernel method to determine the amountof a
radionuclidein a radioisotope-production hotcell. 36th Annual Congress of the
South African Association of Physicists in Medicine and Biology, Pretoria, June
VAN ROOYEN, TJ. 1998. Report on Koeberg's Radiation Safety Programme.
iThemba LABS, PO Box 722, SOMERSET WEST, 7129, South Africa. 5 p. Report
prepared for NOSA.
VAN ROOYEN, TJ. 1999. Radiation Safety Assessment of the INFRUITEC
Irradiator. iThemba LABS, PO Box 722, SOMERSET WEST, 7129, South Africa.
VAN ROOYEN, TJ. 2000. Review of ESKOM Report NSD-R99/001: Operator
Risk dueto the use of 17x17 Westinghouse374 RobustFuel.
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VAN ROOYEN, TJ. 2000. Review of ESKOM Report NAAS-R99/014:Release
Fraction Analysis for Westinghouse RobustFuel.
VAN ROOYEN, TJ. 2001. Calculation of external dose rates next to containers
filled with zirconia.
KEGOPOTSAMENG, O & VAN ROOYEN, TJ. 2004. Evaluation and proposed
redesign of radiation shielding at the RadionuclideProduction Facility at
iThemba LABS. iThembaLABS, PO Box 722, SOMERSET WEST, 7129, South
MATSIETSA, KI & VAN ROOYEN, TJ. 2004. Naturallyoccurring radioactive
material (NORM) and associated radiation protection issues in selected minerals-
extraction industries. iThemba LABS, PO Box 722, SOMERSET WEST, 7129,
VAN ROOYEN, 2004. Protection of electronic apparatusagainstdamageby
ionising radiation. iThemba LABS, PO Box 722, SOMERSET WEST, 7129, South
LUKHELE FM, BUTHELEZI EZ, STEYN GF, NDWANDWE OM & VAN
ROOYEN, TJ. 2006. Design calculations for the local radiation shield of a
radioisotope production target bombardmentstation – a comparative study.
VAN ROOYEN, TJ. 2006. The Science of Radiation Protection. iThemba LABS,
PO Box 722, SOMERSET WEST, 7129, South Africa. 550 p.
VAN ROOYEN, TJ & SIBIYA, T. 2007. Radiation Shielding Assessment for the
HEPRO (Cape) IrradiatorOperating with a 2 Megacurie 60Co Source. Necsa RRT
ReportRRT-SHLD-07-03. Necsa, PO Box 582, Pretoria, 0001, South Africa.
VAN ROOYEN, TJ & SIBIYA, T. 2007. Radiation Shield Design for the Citrusdal
Insect Irradiator. Necsa RRT Report RRT-SHLD-07-04. Necsa, PO Box 582,
Pretoria, 0001, South Africa.
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VAN ROOYEN, TJ. 2007. Influence of 234U and 236U in Rig Target Plates on the
99Mo Production Rate in the SAFARI-1 Reactor at Necsa. Necsa RRT Report RRT-
SHLD-07-06. Necsa, PO Box 582, Pretoria, 0001, South Africa.
VAN ROOYEN, TJ. 2008. Threshold energies of emitted radiationsthat will
produce nuclear recoils energetic enough to cause chemical bond rupture in
radioactively labeled molecules employed in nuclearmedicine procedures, with
specific application to the therapeutic radionuclides 103Pd/103mRh. NecsaRRT
ReportRRT-SHLD-08-01. Necsa, PO Box 582, Pretoria, 0001, South Africa.
VAN ROOYEN, TJ & KUPI, TG. 2008. Design of a local radiation shield for a
radionuclideproduction beam target station. Necsa Report RRT-SHLD-08-03.
Necsa, PO Box 582, Pretoria, 0001, South Africa.
TJ van Rooyen. 5 February 2008. Threshold energies of emitted radiation quanta
that willproducenuclearrecoils energetic enough to cause chemical bond rupture
in radioactivelylabeledmolecules, withapplication to the therapeuticradionuclides
103Pd103mRh. Necsa Report RRT-FMR-08-03.
TJ van Rooyen. 17 June 2008. Report on Collaboration withiThemba LABS, 26-
30 May 2008. NecsaReportRRT-FMR-08-04.
TJ van Rooyen. 3 May 2007. Radiation ShieldingAssessmentfor the HEPRO
(Cape) IrradiatorOperatingwitha 2 Megacurie60Co Source. Necsa Report.
TJ van Rooyen. 12 February 2009. Conceptual design ofa new source holder for
the Necsa calibration facilityfor radiation detectors. Necsa Report.
TJ van Rooyen. 21 August 2008. Radiation Damageto Ion-ExchangeResin in an
NTP RadionuclideProduction Hotcell.
TJ van Rooyen. 7 September May 2007. Radiotoxicityfrom chemical bond rupture
from recoil nuclei in nuclearmedicineapplications. Necsareport RRT-SHLD-07-
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TJ van Rooyen, JA Koch & N Govender. 15 December 2009. Neutron-Induced
Changesin the Aluminium-AlloyComposition of the Core-Box of the SAFARI-1
Reactor at Necsa. Necsa Report RRT-SAFA-REP-09039.
TJ van Rooyen. 3 September 2009. Design of a Shielding Wall aroundthe NTP
Decay Yard for RadioactiveWaste. Necsa report RRT-SHLD-REP-09003.
TJ van Rooyen. 18 March 2010. Maximum SurfaceDose Rates on Rowsof
RadioactiveWasteDrums in the NTP Decay Yard, thatwillmaintain the Dose Rate
at the PerimeterFence at 2.5µSv/h. Necsareport RRT-SHLD-REP-10001.
TJ van Rooyen. 15 April 2010. Dose Rates Around an NTP Type A70 Transport
Containercontaining either16 Ci 99Mo or 18 Ci 131I. Necsa report RRT-SHLD-
TJ van Rooyen. 7 July 2010. CriticalitySafetyAssessment of the New Layoutof
the NTP Dissolver Hotcell, for the processing of LEU. Necsa report RRT-CRIT-
TJ van Rooyen. 16 September 2010. Estimated Influence of 236U in Rig Target
Plateson the 99Mo Production Rate. RRT-SHLD-MEM-10001.
TJ van Rooyen. 24 June 2010. The impactof detailed beta-particlespectra on
calculated electron depth-dose-distributionsand on bremsstrahlungproduction.
Necsa RRT Report.
TJ van Rooyen. 16 June 2010. RRT-SHLD-REP-10008. Dose Rate Calculations
for the New NTP 192IrHotcell. Necsa Report.
TJ van Rooyen. 2010. Physics of Nuclear Reactor Operation—PartII.
TJ van Rooyen. 11 November 2010. Dose Rates Around Different NTP Type A
PackagesContaining99Moor 131I. Necsareport RRT-SHLD-REP-10013.
TJ van Rooyen. 1 August 2010. Concrete Drum ShieldingRequirementsfor 99Mo
Production Waste at NTP. Necsa report.
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TJ van Rooyen. 28 March 2011. Energy Deposition Rate, Dose Rate and Shielding
Requirementsfor a 4000 Ci 99Mo Source in the New Dissolver Hotcell at NTP.
Necsa report RRT-SHLD-REP-10010.
TJ van Rooyen. 28 March 2011. Absorbed Dose Rates from 99Mo in AGMP-1M
ColumnsUsed by NTP. RRT-SHLD-REP-11008.
TJ van Rooyen. 25 June 2012. Design function of different materialsin NTP's
“BEATRICE”transportpackage. Technical memorandum.
TJ van Rooyen. 29 August 2012. Dose rates outside NTP Hotcell-2 holding the
solid radioactivewastefrom 53760 processed Moly-production TargetPlates.
Necsa report RRT-SHLD-REP-12003.
TJ van Rooyen. 30 November 2011. Doses Around the NTP Lead-WalledHotcells
11, 19 and 20 in the Eventof CriticalityAccidents. NecsaReport RRT-CRIT-REP-
TJ van Rooyen. 24 December 2011. Source Term and Dose Assessment in the
Eventof a CriticalityAccidentin an MTR Fuel ManufacturingFacility. Necsa
TJ van Rooyen. 25 March 2011. The Irradiation of 176Yb for the Production of
177Lu: Yield, Dose-Rates and Shielding Requirements. Necsareport RRT-SHLD-
TJ van Rooyen. 8 March 2012. Maximum Activitiesof 192Ir, 75Se, 60Co and 137Cs
that maybe transported in NTP Type A Transport Packages29/15/A-96, 29/30/A-
96 and 29/44/A-96. Necsareport RRT-SHLD-REP-12002.
TJ van Rooyen. 25 November 2011. Doses Around the Concrete-Walled NTP
Hotcells 2 and 3 in the Event of CriticalityAccidents. Necsareport.
TJ van Rooyen. 22 October2009. Dose Rates from SpentFuel Assembliesto be
Shipped in 2010. Necsareport RRT-SHLD-REP-09005.
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TJ van Rooyen. 22 January 2010. CriticalitySafetyAssessment for the Uranium-
Waste Frame-Rack (UWFR)in NTP Hotcell 3. Necsa report RRT-SHLD-REP-
TJ van Rooyen. 7 August 2013. Shielding andDose Rate Calculationsfor 8 GBq
TJ van Rooyen. 19 February 2013. Radiation Dose to Workers Following
Hypothetical Fuel Damage in a Materials Testing Reactor (MTR). Necsa Report
TJ van Rooyen. 7 August 2013. Shielding and Dose Rate Calculations for 8 GBq
177Lu. Necsa Report RRT-SHLD-REP-13006.
TJ van Rooyen. 15 August 2013. Dose Rate Calculations for a Type-A Container
with 10 Ci 99Mo. Necsa Report RRT-SHLD-REP-13005.
TJ van Rooyen. 15 January 2014. Maximum activity of 192Ir that may be safely
handled in NTP Hotcell 2. Necsa Report RRT-SHLD-REP-14001.
TJ van Rooyen. 3 November 2014. Radiological Safety of Producing 223Ra
Generators by Irradiating 226Ra in a Nuclear Reactor. Necsa Report RRT-SHLD-
TJ van Rooyen. 24 November 2014. Dose Calculations for an Operator Drenched
in Primary Coolant Leaking from a Nuclear Reactor. Necsa Report RRT-SHLD-
TJ van Rooyen. 25 September 2015. Transport and Shielding of Ionising
Radiation. (Postgraduate University Textbook.)
TJ van Rooyen. 4 November 2015. Shield Design Calculations for the SRSS
Service Station for the Silicon Roller Assembly (SRA) at the SAFARI-1
Reactor. Necsa Report RRT-SHLD-REP-15003.
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TJ van Rooyen. 20 November 2015. Shield Design for the Disposal of a 300 Ci
90Sr Source. RRT-SHLD-REP-15004.
TJ van Rooyen. 10 December 2015. Shield Design Calculations for the New
Neutron Radiography Facility at Necsa. Necsa Report RRT-SHLD-REP-15005.
Numerous papers & posters presented at conferences.
Numerous Mathematical models of radiation protection & transport problems.
Numerous Fortran peripheral shielding & data analysis codes.
Contributions to the Radiation Safety Information ComputationalCenter
(RSICC), Oak Ridge NationalLaboratories,USA
VAN ROOYEN, TJ. 1993. BUCORST: A code to prepare Burnup-dependent
Multigroup Nuclear Reactor Source Terms. RSICC Code Package PSR-339.
VAN ROOYEN, TJ. 1993. PRE-ANISN: A Preprocessing Code for ANISN and
Other Radiation Transport Codes. RSICC Code Package PSR-332.
Other publications and contributions
Presented numerous papers and posters on the subject of radiological protection at
conferences and workshops in Southern Africa.
1. Developed & present a postgraduate course on Radiation Transport & Shielding
& Radiation Protection at Stellenbosch University, South Africa. Presented
1991 – 2006.
2. Developed & present a postgraduate module on Radiological Protection at
Northwest University (NWU), South Africa. 1998 – 2007.
3. Developed & present a postgraduate module on Radiological Protection at the
University of the Western Cape, Bellville, South Africa. 2004 – 2006.
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4. Presented Nuclear Physics 3 at the University of the Western Cape (UWC) in
5. External examiner to several M.Sc. dissertations in (1) Probabilistic Safety
Assessment (PSA), (2) Nuclear Reactor Science, (3) Reactor Core Management
Calculations, (4) Radiation Shielding and (5) Land rehabilitation following TE-
6. Presented 2-day Radiation Protection Officer training courses to many hundreds
of candidates throughout all provinces of South Africa, from year 2000 –
7. Radiation Protection & Transport lectures, WITS University, 2007.
8. Developed and taught postgraduate module: Radiation Transport, Shielding &
Criticality Safety, NorthWest University (Mafikeng Campus), 2008 – present.
9. Developed and taught postgraduate module: NuclearPhysics for Nuclear
Engineers. NorthWestUniversity (PotchefstroomCampus), 2008 – 2010.
Presented for PostGraduateDiploma in Nuclear Engineering, at Koeberg
Nuclear Power Station, ESKOM, Western Cape, South Africa.
10. Postgraduate teaching at UNAM (Windhoek), NWU (Potchefstroom) and UCT.
Subjects: Radiation Protection, Radiation Transport & Radiation Shielding.
Years span 2013 to the present.
1. TJ van Rooyen. The Science of Radiation Protection.
2. TJ van Rooyen. Nuclear Physics for Nuclear Engineers.
3. TJ van Rooyen. Transport and Shielding of Ionising Radiation.
The above three textbooks, as well as several informative slideshows, are available
from the above website as free downloads to all interested persons.
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Postgraduates led to M.Sc. degrees: 1999
1. Ms Lesego Mogapi. 2000. M.Sc. in Environmental RP. Northwest University.
Presently at PMBR, Centurion. Tel: 012-677-9467.
2. Mr Wilbert Leotwane. 2001. Co-leader for M.Sc. in Probabilistic Risk
Assessment (PRA). Northwest University.
3. Ms Refilwe Letebele. 2001. Co-leader for M.Sc. in Radioactive effluent release
management. Presently at Koeberg, ESKOM. Northwest University. Tel: 021-
4. Ms Naomi Mokoto. 2001. Co-leader for M.Sc. in Environmental RP around a
nuclear power station. Presently at Koeberg, ESKOM. Northwest University.
5. Mr Rothi Mashigo. 2001. M.Sc. in Re-Programming a Radiation Shielding
Code from Fortran-4 to Structured Fortran-95 & Benchmarking it. Northwest
University. (Deceased – tragic car accident early 2002).
6. Mr Senoelo Pheto. 2001. M.Sc. in radiation shielding.
7. Ms Kgomotso Matsietsa. 2003. MSc dissertation in RP against sources of
NORM (Naturally Occurring Radioactive Material) was completed in 2003, but
not accepted by Northwest University (NWU) – the candidate was too
dependent on my input & failed to develop independent problem-solving skills.
8. Ms Onalenna Kegopotsemang. 2004. M.Sc. in Radiation Protection at a
Particle Accelerator Radionuclide Production Facility. Completed & accepted
in 2003. Northwest University. Tel: 082-368-4653.
9. Mr Tebogo Kupi. 2008. MSc in shield design for a radionuclide production
target bombardment facility at a particle accelerator facility, using the code
MCNPX. Dissertation handed in December 2007.
10. Mr Thomas Sibiya. 2008. MSc in Radiation Protection. Radiation shield
design & verification for 3 irradiator facilities using strong 60Co sources. WITS
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11. Ms Bessie Makgopa. 2008. Co-leader for Masters Degree in Nuclear
Engineering, NorthWest University (Potchefstroom Campus). Dissertation
topic: MCNP Model for rig to test PBMR fuel spheres.
12. Mr Willem Bekker. 2009. MSc in Radiation Protection. WITS University.
Topic: Modelling in-building radiological consequences of a release of radio-
nuclides to reactor coolant and the atmosphere, at a Materials Test Reactor
13. Mr Nicolin Govender. 2010. MSc in Physics Energy Studies. Field: Nuclear
Reactor Modelling. University of Johannesburg.
14. Mr Eric Chinaka. 2014. MSc in Physics Energy Studies. Field: Radiation
Shielding in Diamond Detection. University of Johannesburg.
Dr Djordje Tomasvic, Necsa, South Africa. Radiation & Reactor Theory
Section. Email: email@example.com
Prof John Carter, WITS Schoolof Physics, University of Witwatersrand,
Johannesburg, South Africa. firstname.lastname@example.org
Prof FB Waanders, Pr. Eng., Pr. Sci.Nat.
Schoolof Chemical and Minerals Engineering North West University
Dr Bismark Tyobeka
CEO: NNR, Centurion, Gauteng, South Africa.
Dr Tobie Kotze
Department Medical Physics
University of Cape Town
Page 27 of 27
Mr Senoelo Pheto, NNR, Centurion, South Africa.
Dr Iyabo Usman, WITS.
Mr James Larkin, WITS.
Prof James Oyedele, UNAM.
Dr Bismark Tyobeka, CEO: NNR.
Mr Zukile Zibi, TIA.