ML20248F629
| ML20248F629 | |
| Person / Time | |
|---|---|
| Site: | 07000113 |
| Issue date: | 05/26/1998 |
| From: | Randy Erickson PENNSYLVANIA STATE UNIV., UNIVERSITY PARK, PA |
| To: | NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| NUDOCS 9806040361 | |
| Download: ML20248F629 (46) | |
Text
,
(814)863-9580 L
PENNSTATE "Off"'"
Rodney A. Erickson The Pennn vania State University i
vice President for Research 304 Old Main Dean of the Graduate School University Park. PA 16802 1504 May 26,1998
)
U. S. Nuclear Regulatory Commission
' Fuel Cycle Safety Branch Division ofIndustrial and Medical Nuclear Safety Washington, D. C. 20555-0001 i
License No. SNM-95 Docket No.70-113
Dear Sir or Madam:
The Pennsylvania State University requests renewal of Special Nuclear Material license number SNM-95, which will expire June 30,1998. The University is a nonprofit educational institution incorporated under the laws of the Commonwealth of Pennsylvania and is exempt from license fees in accordance with 10CFR171.11(a)(1). It is governed by a board of trustees, all of whom are citizens of the United States.
I certify that all statements in the following application ~are true to the best of my knowledge and that all statements and representations made in this application are binding on The Pennsylvania State University.
Thank you for considering this request.
Sincerely, i
\\
l 9806040361 990526 PDR ADOCK 07000113 C
PDR Penn State University License: SNM-95 Docket 70-113 Page 1 An Equalopportunity University if
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1.
REQUESTED AMOUNTS, FORMS, and USES The radionuclides requested, their physical forms, the amounts requested, and the allowed use of the materials use are below. No changes are requested from the existing license.
A.
132 grams of 2"U, any fonn This material is used at University Park in fission counters and chambers for neutron detection with the Penn State Breazeale Reactor (NRC license RO-2) and other neutron sources, in fission fragment irradiation of various material or for flux monitoring.
B.
I100 kilograms 2n.2"UO contained in 417 Pathfinder Superheat Fuel Elements, 415 2
elements enriched to 6.95 weight % "U, and two elements enriched to 7.5 weight % "U.
2 2
This material is in storage awaiting disposal. As soon as shipping containers are available this material will be returned to the Department of Energy. The fuel assemblies are stored in a 12 foot square room in the basement of the Academic Projects Building. The locked door to the room is constructed of steel plate and keys are only issued to licensed Penn State Breazeale Reactor senior reactor operators. The room is equipped with intrusion alarms to a continuously monitored alarm panel. The floor plan for the Academic Projects Building, the storage rack drawing, the floor plan for the fuel storage room, and excerpts from the Pathfinder Atomic Power Plant Safeguards Analysis for the Second Core Loading (ACNP-67525) were included as Supplement A-2 to the application for renewal of License SNM-95 dated April 21,1978. The rooms adjacent to the fuel storage room are currently used for engineering research and for storage. The area labeled " Linac Machine Room"is used by the Radiation Protection Office for radioactive waste storage and as a calibration room. The high density concrete shield wall between the two areas isolates the fuel storage room from any radiation sources.
The fuel assemblies are stored on the same storage racks previously used by Northern States Power Company under license DPC-11. Criticality calculations used by Northern State Power Company sb enhat the erage racks loaded with fuel have a k,, ofless than 0.8 when flooded with waier. The storage arrangement used by the University should be at least as safe as that used by Northern State Power Company. An exemption to the -
requirements of 10CFR70.24 for a criticality monitor in the storage room is requested because the area is not normally occupied and the critically analysis indicates a k,n fless o
than 0.8 for the worst case (flooded storage room). Such an exemption was previously granted under this license.
C.
Three (3) grams 2nU, any form.
This material is used in the same manner and in the same locations as that described in item A. above.
2 D.
180 grams '?Pu in sealed plutonium-beryllium neutron sources.
This material is in seven Pu-Be sealed neutron sources manufactured by Mound Laboratory. Six of the sources (serial numbers M102, M103, M104, M105, M106, and M187) each contain approximately 16 grams of plutonium, and one (number M317) contains Penn State University License: SNM 95 Docket 70-113 Page 2 I
about 80 grams ofplutonium. There are no plans to acquire more neutron sources. All sources are currently used and stored in the Radiation Science and Engineering Center or the l
Academic Projects Building.
)
These sources are used in student experiments to demonstrate the properties of neutrons and moderators, for neutron activation, and neutron detector calibration. They are primarily used in a suberitical graphite pile (see item F below) but are also used in air or water. The sources are sometimes used in the pool of the Cobalt-60 facility (license 37-185-
- 5) or in the pool of the Penn State Breazeale Reactor (license RO-2), but are never used for in-core experiments.
l E.
Five (5) microcuries of 2"Pu as plated alpha sources in fission foils.
This plutonium is plated on metal backings to form alpha sources and fission foils.
The alpha sources are used for the calibration and testing of alpha detection l
. equipment and for demonstrations of the properties of alpha particles. PSU currently has ten (10) of these sources manufactured at the Savannah River Plant with a total activity of about 0.12 uCi of plutonium (2 micrograms). These foils may be used throughout Pennsylvania as i
part of educational programs or to check instruments.
l l
The fission foils are used for neutron flux measurements with the Penn State l
Breazeale Reactor and other neutron sources. The current inventory includes 3 foils with an l
activity of 3.8 uCi(61 micrograms).
F.
2500 kilograms of encapsulated natural uranium.
I This natural uranium is used in a graphic subcritical pile. The pile has been used without incident since 1958 for student laboratory experiments in nuclear engineering. The i
subcritical pile is located in a the Academic Projects Building, but may also be used in the l
Radiation Science and Engineering Center. It is described in an attachment to this application.
In general, doses to personnel using the pile have been less than the minimum i
l reporteSle value (10 mrem) of the dosimeter processor. For a pile loaded with four 16 gram l
Pu-Be sources (item D above), the dose equivalent rate is 0.2 mrem per hour at two meters i
from the source face of the pile and less than 0.1 mrem per hour at two meters from the other sides of the pile.
l G.
10 kilograms of source material, any chemical form, solid or liquid.
l This material is natural thorium and natural or depleted uranium which is used for 1
. chemical experiments in research laboratories. It is primarily used for ceramic and geophysical research and as a contrast medium for electron microscopes.
This material is used and stored in the Radiation Science and Engineering Center and the Academic Projects Building but may be used at other University Park locations. This material is in addition to the 15 pounds of source material authorized under 10CFR40.22.
Penn State Univendty License SNM 95 Docket 70-113 Page 3 l
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i 2.
PURPOSE All licensed material will be used for research and development as defmed in 10CFR30.4, for teaching, for training, for calibration ofinstruments, for determination of neutron flux in the Brezcale Nuclear Reactor (License RO-2), and as components of analyticalinstruments.
3.
INDIVIDUALS RESPONSIBLE FOR THE RADIATION SAFETY PROGRAM 3.1 Senior Management The Vice President for Research and Dean of the Graduate School is the senior University official responsible for licensing the safety programs for radioactive materials. The Vice President for Research and Dean of the Graduate School appoints the University Isotopes Committee members to control the use of radioactive materials within federal, state and University regulations and to perform those functions required of a radiation safety committee by the Federal regulations and this license.
The Office of Regulatory Compliance is also administered by the Vice President for Research and Dean of the Graduate School. The Office of Regulatory Compliance is responsible for providing support for the University Isotopes Committee as well as for those committees which regulate research on human subjects, animal care and use, and biosafety.
The Director of this office is a member of the UIC and represents senior management at the Committee meetings. On matters ofradiation safety policy, the Committee reports directly to the Vice President for Research and Dean of the Graduate School. On matters of radiation safety the Manager of Radiation Protection reports to the Vice President for Research and Dean of the Graduate School through the University Isotopes Committee (see the dashed line in the organization chart).
The Environmental Health and Safety office is administered by the Senior Vice President for Finance and Business who provides additional administrative support for its programs, which include the Radiation Protection program.
The organization chart showing these relations is on the next page.
Penn State University License: SNM 95 Docket 70113 Page 4
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3.2 University Isotopes Committee (Radiation Safety Committee)
The University Isotopes Committee (UlC) is responsible for directing activities under the licenses issued to the University for the use of radioactive materials and for insuring that such use meets federal, state, and University regulations. The Committee is composed of faculty members representing those areas of research and teaching which are the main users of radioactive materials, has a member who represents senior management, and may include non-university personnel with experience with radioactive material. The Penn State Radiation Safety Officer (title: Manager of Radiation Protection, Office of Environmental Health and Safety) attends all meetings.
The Vice President for Research and Dean of the Graduate School delegates to the University Isotopes Committee the authority and responsibility to review all requests for the use of radioactive materials and to approve or deny such requests. The Committee also has the authority and duty to withdraw its authorization to use radioactive material and to order an experimenter to take whatever action the Committee deems necessary to correct a situation which could produce a hazard to personnel or property, or could lead to a violation of a license or regulation. The Radiation Protection staff evaluates all requests for authorization to use radioactive material prior to action on the request by the UIC. The Reactor Safeguard Committee is also a vital component of the review process for proposals involving significant quantities of special nuclear material or source material.
The Committee is responsible for and has the duty to:
1.
Review and approve all uses of radioactive material, 2.
Specify the requirements for training of radioisotope users, 3.
Specify the requirements for radiation and contamination surveys, 4.
Review audits of the radiation safety program, 5.
Formulate University rules and procedures for the use of radioactive material, 6.
- Approve University license applications for possession, use and transfer of radioactive material, 7.
Review letters of agreement with outside agencies, and 8.
Maintain a list of current members and their qualifications.
The Committee evaluates all requests for authorization to use radioactive material.
Autho'izations may be approved for a specific time period not to exceed three years.
r The UIC Chair may appoint subcomnuttees of members or non-members with knowledge in specialized areas, to evaluate reports, applications, contracts, or audits, and to report their findings to the full Committee for review. If necessary the Chair may suspend authorizations prior to informing the other members of the Committee. -
UIC meetings will be held four times a year, approximately quarterly. A quorum consists of more than 50% of the members. Records of meetings and evaluation of requests to use radioactive materials are maintained by the Radiation Protection Office.
L On the recommendation of the Radiation Protection staff, the Chair may increase the L
supervisor's possession limit up to five times the original activity.
The U!C has authorized Radiation Protection staff to amend locations of use of radioactive material covered by previously approved authorizations (within the bounds of University Park and this license).
Penn State Univendty Licenne: SNM-95 Docket 70-113 Page 6
' The University Isotopes Committee (Radiation Safety Committee) has at least eight members.. All members, except the representative of management, must have sufficient training and experience to assure that authorization requests are properly evaluated.
Members will represent colleges in which radioactive materials are used to a significant extent. The NRC will be notified of any changes in membership. The current membership is'.
1.
A. T. Phillips, Ph.D., Chair University Isotopes Committee, Professor ofBiochemistry Training:
Attended radioisotope training programs at Michigan State University and in the Nuclear Science Center at Louisiana State University in 1%5.
Experience: Received extensive experience as a graduate student (1%1-64) working on path of carbon fixation in C-4 plants and conducting chemical carbon-by-carbon degradation of fixation products to establish labeling patterns As a graduate student and later as a faculty member at Louisiana State University (1964-66) and the Pennsylvania State University (1%7-present) conducted enzyme mechanistic studies using 100-500 mci quantities of tritiated water and 10-100 mci amounts of tritiated sodium borohydride. More recently has been involved in research utilizing S and 85 32P for biological labeling studies with bacteria and tissue cultured cells,-
plus considerable work with DNA sequencing and protein modification experiments.
- 2. Craig Baumrucker Ph.D., Professor of Animal ' Nutrition / Physiology Training:
Attended two prerequisite courses for isotope use at Purdue University, PHAR 512 - Introduction to Bionucleonics (2 cr) and PHAR 522 - Applied Bionucleonics. Attended the PSU radioisotope users training program and was trained and monitored in the use ofi2sl protein labeling procedures.
- Experience: During his three years at Purdue, utilized "C and 32P tagged biologicals for a number ofin vitro enzyme assays. In 1974, became an Assistant Professor of Dairy Science at the University ofIllinois at Urbana Champaign. Continued use ofin vitro assay on enzymes and expanded into studies with membrane transport studies with '5Ca, 32P, "C, and 'H. In 1981, became an Associate Professor at the Pennsylvania State University.
l Had numerous "C and 'H isotopes transferred from IL to PA. Current
- laboratory is conducting in vitro transport and labeling studies with extensive use of"C, 'H, and 85S. The use of125Ilabeled proteins is for radio-immune assays (RIA) and radio receptor assays (RRA). In 1987, received approval and conducted a study in vivo with "'I labeled protein feeding to a calf maintained at the Central Biological Labs at PSU.
- 3. William Jester Ph.D., Professor of Nuclear Engineering Training:
M.S. Nuclear Engineering, Ph.D. Chemical Engineering, thesis on use of neutron activation for analysis of trace elements
- Experience: Over 35 years of research in neutron activation analysis, industrial use of Penn State University License: SNM-95 Docket 70113 Page 7 E.
..j
radioisotopes and radiation monitoring. Instructor for a health physics course in the Nuclear Engineering Department. About 20 years experience in designing radiation monitoring systems for the nuclear industry.
Founder and technical supervisor of Penn State University Low Level Radiation Monitoring Lab. Has used radioactive materialin microcurie to curie levels. Instructor of radiation detection and measurement laboratory
- courses for over 30 years.
- 4. Edward Kenney, Ph.D., Professor Emeritus of Nuclear Engineering Training:
Oak Ridge Institute of Nuclear Studies Radiological Physics Fellowship; University of Rochester and Brookhaven National Laboratory 1953-54.
M.S. and Ph.D. thesis in nuclear spectroscopy.
Experience: Served as Radiation Surveyor 1954-55 at Westinghouse Bettis Field Plant, Pittsburgh, PA. Served as University Health Physicist, The Pennsylvania State University 1955-59. Instructor Health Physics course in the Department of Nuclear Engineering. Has handled a variety of radioisotopes from tracer to multi curie levels in sealed and unsealed form as health physicist, reactor supervisor, during graduate research in nuclear physics and as a faculty member. Has designed ion chamber survey meters, irradiators, air monitors and other health physics instruments. Has patents.
on Dynamic Radiography and Neutron Bottle.
- 5. Louis Persic, M.D. Director of Nuclear Medicine, Centre Community Hospital Training:
Board certification in radiology by the American College of Radiology 1
and in nuclear medicine by the Society of Nuclear Medicine.
Numerous continuing education credits in radiology, nuclear medicine and radiation safety, including a two week course at the Oak Ridge Institute ofNuclear Studies.
Experience: Practicing nuclear medicine physician since 1974. Radiation Safety Officer for Centre Community Hospital, State College, PA since 1976.
- 6. Arthur Rose, Ph.D., Professor Emeritus of Geochemistry Training:
Course in Radioactivity and Isotopes at California Institute of Technology.
Experience: Use of neutron activation to determine a number of elements in rocks'and soils, including rare earth elements, Zn, Au, Ag, and Se. Development and use of delayed neutron activation methods for U and Th in rocks, soils and waters at trace levels, for application in uranium exploration, uranium deposit origin, and radon abundance. Investigations of radon and radium in groundwater and soils, including a DOE grant studying the chemical form of radium and the controls on radon in soil gases, and a literature study on plutonium behavior in the environment.
- 7. John Smith, Ph.D., Associate Professor of Human Nutrition Training:
Graduate level 3 credit course in Radioisotope Use and Theory at University of Nebraska. Taught seminar on radiation safety to graduate students at Columbia University.
Experience: Has used *I and *I in millicurie amounts for the iodination of proteins.
Has used amino acids in protein synthesis and incorporation in whole Penn State University Liccuse: SNM-95 Docket 70-113 Page 8 lL___________._.________.__
animal models. Has used 5S in amino acids and in vivo protein synthesis.
Has used 'll in vitamin A and in turnover of vitamin D in human subjects plus "C as retinal esters. Is currently active in research using 11, "C, i25g 5
in retinol binding protein studies.
8 Candice Yekel, Director of Regulatory Affairs. (representing management)
Training:
B.S., and M.S., in Developmental Psychology Attended Penn State's radioisotopes user training program Experience: Four years of experience working in regulatory compliance areas, as the Compliance Coordinator and Research Integrity Officer for Penn State.
Promoted to the Director for Regulatory Affairs in 1997, 3.3 Radiation Safety Officer The Manager of Radiation Protection (Radiation Safety Officer, RSO) is responsible for l
assuring that all radioactive materials are used in accordance with good health physics practices and applicable regulations. The RSO attends all meetings of the University Isotopes Committee and provides advice to the committee on all matters. Under the RSO's supervision, the Radiation Protection staff will:
1.
Assist users of radioactive materials in developing safe research programs and procedures.
2.
Evaluate applications for use of radioactive material at Penn State.
3.
Maintain surveillance of all activities involving radioactive material, including monitoring and surveying all areas in which radioactive material is used.
4.
Enforce compliance with rules and regulations, license conditions, and the conditions of project approvals authorized by the University Isotopes Committee 5.
Monitor and maintain absolute and other special filter systems associated with the use, storage, or disposal of radioactive material.
6.
Provide information on all aspects of radiation protection to personnel at all levels of responsibility, pursuant to 10 CFR 19.12 and 10 CFR Part 20.
7.
Oversee delivery, receipt, and conduct of radiation surveys of all shipments of radioactive material arriving at or leaving the university, as well as overseeing proper packaging and labeling all radioactive material leaving the university.
8.
Distribute and process personal radiation monitoring equipment, decide the need for and evaluate bioassays, monitor personal radiation exposure and bioassay records for trends and high exposures, notify individuals and their supervisors of radiation exposures approaching maximum permissible amounts, ami recommend appropriate remedial action.
9.
Oversee training programs and otherwise instruct personnel in the proper procedures for handling radioactive material prior to its use and instruct personnel, when required, about changes in procedures, equipment, regulations, etc.
- 10. Dispose of radioactive waste by release to the sanitary sewage system, decay-in-storage, or by shipment to a licensed disposal facility. This procedure includes effluent monitoring and keeping records on waste storage and Penn State University lxcuse: SNM-95 Docket 70-113 Page 9
[
disposal.
- 11. Store radioactive materials not in current use, including wastes.
- 12. Perform or arrange for leak tests on all sealed sources.
[
- 13. Calibrate radiation survey instruments.
- 14. Maintain an inventory of all radioisotopes at the university and limit the quantity of radionuclides to the amounts authorized by this license.
- 15. Immediately terminate any activity at the university that is found to be a threat to public health and safety or to property.
The current Radiation Safety Officer is Eric Boeldt, Manager of Radiation Protection.
Training:
Masters Degree in Medical Physics (Health Physics option) from the University of Wisconsin at Madison. Cenified in health physics by American Board of Health Physics,1988. Decertified through 2000.
Experience:
Associate Health Physicist at University of Wisconsin-Madison 1981
- 1987. Associate Health Physicist at Penn State University 1987 -
1997. RSO at Penn State since September 4,1997.
l 3.4 Radiation Protection Staff i
The Manager of Radiation Protection (RSO) is a full-time, permanent employee supported by five full-time staff (one Associate Health Physicist and four Health Physicist Specialists). Clerical support is provided by Environmental Health and Safety staff. All full-time, permanent personnel in the Radiation Protection program have experience in health physics. Management is committed to maintaining a strong Radiation Protection staff and to providing adequate staffing.
l l
I l.-
Penn State University License: SNM-95 Docket 70-113 Page 10
l e
- 4. Training for Individuals Working in or Frequenting Restricted Areas.
. Penn State University will train employees, students, and visitors to comply with j
10CFR19.12. An outline, for information only, of the topics covered in this training is enclosed to aid the reviewer.
Most personnel who work with radioactive material will have taken the basic Radiation Protection training course. Penn State employees who attend this basic training session must score at least 70% on an exam on course content. Records of training and test results are maintained by EH&S. Training will normally be presented by Radiation Protection staff experienced in handling radioactive material.- If other personnel provide the training, the
. course content will be approved in advance by the RSO.
i l
In the future these basic training sessions may be replaced by a computer based training l
program under the supervision of Radiation Protection staff as approved by the UIC.
In addition to this basic training, all laboratory supervisors (Authorized Users) are required to train their staff and students in the specific procedures and techniques required in l
their specific projects. This training is required for all radiation workers.
l Special training will be given those required to transport radioactive material on public roadways.
l Radiation Protection staff will distribute a regular newsletter to authorized users (supervisors) of radioactive material. This newsletter will update supervisors on changes in regulations, rules, and policies. The >ewsletter will direct each supervisor to share the information with his or her staff.
The UIC may allow staff who are unlikely to receive as much as 100 mrem in one year to be exempted from the basic training course. A copy of the current exemption request form is enclosed as an example of the information used by the UIC to grant these exemptions, but other information may be collected in specific cases. The form may be modified by the UIC as needs change. Such exemptions would apply primarily to visitors who have had extensive prior experience with licensed materials, and who will be at Penn State for less than six months. The exemption form may also be used to allow PSU staff to start work with radioactive material prior to taking the basic training course. The laboratory supervisors will be responsible for providing specific training commensurate with the position's requirements.
I l
Penn State University License: SNM 95 Docket 70-113 Page 11 i
- 5. Facilities and Equipnient The University has over 250 radioisotope laboratories. A complete list of all laboratories is not practical because of the frequency at ' hich the rooms change. In general, w
rooms authorized for the use of radioactive material are laboratories with sinks, benches, and a fume hoods. Contamination survey meters are available for all laboratories using radioactive material other than tritium. Lab coats, protective eye wear, splash shields, and shielding are available wherever required. Glove boxes are used when needed for experiments requiring control of transferrable contamination or of airborne radioactive material which cannot be handled in hoods. Two hot-cells are also available (see below).
The suitability of any particular laboratory and the requirements for special facilities and equipment for a given procedure are determined by Radiation Protection and the University Isotopes Committee in the review of the experimenter's request to use radioactive material.
5.1 Radiation Protection Facilities and Equipment The Radiation Protection Office has a variety ofinstrumentation available. Portable survey instruments currently include ionization chambers, survey meters with thin-window pancake Geiger-Mueller tubes or thin windowed Nal(TI) crystals, and a neutron rem meter.
Laboratory instmments available include a liquid scintillation counter and multichannel analyzers with thick and thin Nal crystals, and a silicon alpha detector. Various filter holders and pumps, plus velometers and differential pressure meters are available for air sampling and hood evaluations. Many other instmments are also available in campus laboratories, including intrinsic HPGe gamma spectrometers, low-background alpha and beta counters, and liquid scintillation counters (LSC). There are sufficient GM meters available to provide meters to each Radiation Protection staffer and to provide temporary " loaners" to research labs.
Survey instruments used by Radiation Protection for radiation measurements are calibrated by Radiation Protection staff annually, with records of calibration kept for at least three years. Gamma-ray exposure calibration is performed with a Shepherd Model 72 "'Cs calibrator (NRC license 37-00185-%). This cesium source was calibrated with an N!ST calibrated condenser-R meter. Meters are considered to be properly calibrated if the.y read within +or-20% of the true radiation level on all scales. The room where the calibt ator is j
stored is also used to store radioactive waste, but the radiation levels in the room do not j
' interfere with calibrations. The Radiation Protection Office's liquid scintillation counter is calibrated with sources or solutions traceable to the NIST.
Survey instruments used only for contamination monitoring are not calibrated for exposure measurements, but are equipped with check-sources for operational f ests when the l
l instruments are used. All radiation workers are instmeted to perform an operational check on each un-calibrated instrument each time the meter is used. Each laboratory on campus l
which uses radioactive material has access to contamination-monitoring equipment, L
Special instruments that are not routinely used, such as ion chambers for gas samples l
'and pressurized gas samplers,~are calibrated as needed.-
Facilities at the university for storing and processing radioactive waste include a large shielded room (originally designed for a 100 MeV electron accelerator)in the Academic Penn State Unnwsity License: $NM-95 Docket 70113 Page 12 m
i Projects Building. This room also contains a waste compactor and the gamma-ray calibration facility. ' Solid waste is stored for decay here, along with most waste awaiting offsite shipment. At the current rate of waste production, there is sufficient storage for all i
anticipated volumes of waste. This room is used on an almost daily basis for the preparation I
and receipt of waste containers for use in campus laboratories. This provides regular observation of stored material. This room is equipped with a sprinkler system.
A small room in the basement of the Academic Projects Building (the " cage") is used for the long-term storage of excess radioactive materials awaiting reuse on campus.
j A third room in the Academic Projects Building is used for processing and storing of liquid waste. This is a ground-level room with natural ventilation, a sprinkler system, and forced ventilation in storage cabinets used for flammable liquid waste. This room is the release point for material discharged to the sanitary sewer. In addition to waste handling areas, the Radiation Protection Office currently has about 1500 square feet of office space, and about 1300 square feet, in two rooms, ofiaboratory space in the Academic Projects Building. These laboratories are equipped with hoods and sinks, and are used for analysis and j
radiochemical preparations. The laboratory and office space assigned to the Radation i
Protection Office may change as the needs of the University change. The NRC will be notified of any significant changes.
5.2 Hot cell facility l
A hot cell facility is part of the Radiation Science and Engineering Center. There are j
two cells with interior dimensions of 7.5 feet by 5 feet by 13 feet high. The walls are 2 feet thick ilmenite concrete (density 3.74 g/ml). The steel clad doors are of the same thickness and material as the walls. The windows are oflead glass, which provides shielding equivalent
' to that of the walls. Each cell has a ventilation system with a pre-filter inside the cell and an absolute filter and fan in the loading area. Exhaust is at the roof of the reactor bay. The cells are equipped with Central Research Laboratories model master-slave manipulators. The normal load capacity of these manipulators is 20 pounds in all positions, but loads up to 100 pounds can be lifted using the load hook in each cell. Most of the work in these rooms has
- been with activated metal reactor components, which have only slight surface contamination.
There has been only one significant contamination problem in a hot cell, and that has been completely decontaminated. The cell was sealed at the time, and there was no release of radioactive material or significant exposure to personnel.
I 5.3 Facility Classification The University Isotopes Committee has approved a three part classification scheme for radioisotope laboratories: White, Yellow, and Red.
White. Radiological Control areas are facilities in which trivial amounts of radioactive material are in use, or areas in which no dispensable radioactive material is used. Examples i
include: gas chromatograph rooms, some LSC counting rooms, some darkrooms, rooms that use iron-55 x-ray sources, and rooms in which only inert radioactive gases are used.
Eating and drinking is not prohibited in these rooms.
l In comparison to the IAEA Safety Standard No.1, the amount of activity typically used j
Penn State University lxense: SNM-95 Docket 70-113 Page 13 i
in these rooms is less than 10% of the limits set for a Type C laboratory.
Yellow Radiological Control areas include almost all rooms where radioactive material is used.
These rooms include all standard molecular biology laboratones and other rooms with similar hazards. Certain other types of work which p nigher than normal contamination hazards are required, by the UIC, to be performed in glove boxes. The rooms in which such work is done are also classified as Yellow Radiological Control areas.
In comparison to the IAEA Safety Standard No.1, the amount of radioactive material typically used in these rooms is normally equivalent to that used in a Type C laboratory.
Red Radiological Control areas are those areas in which large amounts (by PSI' standards) of radioactive material are used or stored. Two examples are the " hot ceas" discussed in item %, and the " cage" discussed in 9a. The reactor bay is also considered a Red area.
As a comparison to the IAEA Safety Standard No.1, the amount of radioactive material typically used in the Hot cells would be equivalent to that permitted in a Type A laboratory.
)
l l
i i
Penn State University 1,iceme: SNM 95 Ikcket 70-113 Page 14
- 6. RADIATION SAFETY PROGRAM 6.1 Previous Licenses i
This application is for the renewal of license number SNM-95 which expires June 30, 1998. Most of the material under this license has been in use since 1960. The University also has the following current licenses issued by the Commission.
- a. Pool irradiator license 37-00185-05 expires: November 20,2003
- b. Self-shielded irradiator license 37-00185-% expires: March 31,2002
- c. Broadscope license 37-185-04 expired June 30,1995 (extended)
- d. Research reactor license R-2 expires: January 27,2006
- e. Quality Assurance Plan 71-0470 expires: January 1,2002 In addition, the University has been issued license number PA-100 for accelerator produced and naturally occurring radioactive material by the Depanment of Environmental Protection of the State ofPennsylvania.
6.2 Administrative Procedures It is the policy of Penn State University, as established by the University Isotopes Committee (UIC), that the release of radioactive material and the exposure of personnel to ionizing radiation be kept As Low As Reasonably Achievable (ALARA). The University ALARA policy is based on the following three levels, which apply to restricted and unrestricted areas and to persons occupationally exposed and to the public.
1.
The dose to personnel or the release of radioactive material may not exceed the limits in the federal and state regulations.
2.
Doses or uncontrolled releases that exceed 10% of the permissible limits will be investigated by the Radiation Protection staff to determine whether the doses or releases were ALARA, and whether action is required to limit future doses or releases Planned experiments with estimated doses or releases that exceed 10% of the permissible limits will be subject to an ALARA review by tne Radiation i
Protection Office prior to the experiment.
3.
Doses and uncontrolled releases that do not exceed 10% of the permissible limits are low enough that no further consideration of ALARA is necessary.
6.3 Procedures for Control of Procumnent and Use of Radioactive Material Procurement of radioactive materials is controlled by the UIC and the RSO. To obtain radioactive materials, a principal investigator and the proposed use must first be approved by the UIC After this approval, the investigator may place an order for radioactive materials.
j All shipments are to the Radiation Protection Office at a central facility. Radiation Protection staff verify the recipients authorization and limits, survey the package in compliance with 10CFR20.1906. Radiation Protection personnel then deliver the packages directly to the i
laboratories that ordered the material. In special circumstances the Radiation Protection Office may give prior approval for shipments to be made directly to their place of use.
Records of all licensed material received at PSU are maintained by Radiation Protection staff.
Penn State University License: SNM-95 Docket 70-113 Page 15
6.4 Emergency Procedures
. Most accidents involving radioactive material are minor and are immediately handled by the laboratory staffs. When a larger mishap-or a mishap of unknown extent--occurs, laboratory workers are instructed to contact the Radiation Protection Office and their laboratory supervisors for assistance. The home and work phone numbers oflaboratory l
supervisors and the RSO are posted on the door of each laboratory.
The Environmental Health and Safety / Radiation Protection telephone is answered at all times. Outside normal working hours, emergency calls are forwarded to a member of the Radiation Protection staff. The Radiation Protection office will decide if offcampus notifications are necessary.
In addition to Radiation Protection staff, in the event of a major spill, Environmental Health and Safety personnel will be available to lend assistance during the initial response to an incident. The Centre County HazMat team is currently based in EHS offices and the complete facilities of that team are also available for use.
6.5 Operating and Handling Procedures 6.5.1 Research Laboratory Procedures.
Specific operating procedures are too varied to be discussed in detail in this document.
Each research procedure and each laboratory has different requirements for operating procedures. However, radioactive material handling procedures required by the UIC are specified below. As necessary, the UIC will change these rules to reflect changes in NRC regulations or license conditions. The " Radioisotope Laboratory Rules" given below are the basic procedures that all personnel must follow.
Radioisotope Laboratory Rules Radioactive materials may only be possessed or used in accordance with authorizations issued by the University Isotopes Committee.
1.
Persons working in radioisotope laboratories must be familiar with regulations and radiation safety procedures. New personnel must contact the Radiation Protection Office to arrange for required safety instruction before beginning work with radioactive materials.
2.
Orders for shipment of radioactive materials to and from the University and transfers between supervisors within the University must be processed through the Radiation l
Protection Office.
- 3.
Inventory forms for radioactive materials must be kept current.- Completed inventory forms must be returned to the Radiation Protection Office when the material has been used up or has decayed to an insignificant activity level.
4.-
People using radioactive materials are responsible for conducting routine surveys to detect excessive contamination or radiation levels each time unsealed radioactive
. materials are used.
5.
People using radioactive materials are responsible for the immediate decontamination of Penn State Unwersity facense: SNM-95 Docket 70-113 Page 16 l
l
facilities which become contaminated in excess of allowed levels.
'6.
Pipetting by mouth is prohibited in laboratories where unsealed radioactive materials are used.
7.
Eating, drinking, or the storage of food or beverages is prohibited in laboratories where unsealed radioactive materials are used, except in laboratories with a " WHITE" emergency classification. Radiation Protection staff has been directed by the University Isotopes Committee to order the use of radioactive materials be stopped immediately in any laboratory in which food or drinks are found. Use of radioactive materials must not resume until the laboratory supervisor has taken action to correct the problem and has received written approval to start work from the University Isotopes Committee.
8.
Radioactive materials must be discarded only into appropriately labeled radioactive waste containers. Radiation Protection staffhas been directed to order the use of radioactive materials stopped immediately in any laboratory in which radioactive material is found in normal trash, biohazard waste, or recycling containers.
Radioisotope use may not resume until the laboratory supervisor has taken action to correct the problem and has received wTitten approval to start work from the University Isotopes Committee.
9.
All containers of radioactive material, which are left unattended, must be labeled with the radiation caution symbol, and data on the radionuclides being used, the activity and the date. Lead shields, cabinets, refrigerators and other storage areas for radioactive material must also be conspicuously labeled.
- 10. Licensed radioactive material in storage must be secure from unauthorized removal or access. Radioactive material not in storage must be controlled and under constant surveillance.
Locking the room which contains radioactive material or storing the materials in a locked cabinet, refrigerator, shield, or storage box meets this requirement. If a room containing radioactive materials is occupied, the radioactive materials must be under constant surveillance of the occupants, or the room must be locked. Radioactive material which is an integral part of a non-portable piece of equipment (e.g. liquid scintillation counter internal standard) is considered secure. Radioactive materials left unattended are in compliance with this requirement if the laboratory door is locked or all radioactive materials, including waste, are in locked storage areas.
6.5.2 Health Physics Procedures The Radiation Protection Office handles routine tasks according to its own standard operating procedures. All procedures are periodically reviewed and modified as needed.
6.5.3 Scaled source procedures The following conditions apply to the use of all sealed radioisotope sources, and will be added to authorizations when relevant.
a) Sources many not be opened or seals modified in any way. Sources may not be machined, ground, drilled, or tapped.
b) Sources must be handled with tongs or other remote devices.
j c) Do not subject sources to potentially damaging conditions such as exposure to Penn State University License: SNM-95 Docket 70-113 Page 17
corrosive chemicals, dirt, abrasion, mechanical shock, temperature extremes, or high pressure unless such conditions have been reviewed and approved by the University Isotopes Committee.
d) Sources may be used and stored only in locations specified in the University isotopes Committee authorizations.
e) If anything unusual happens to the source, it must be reported immediately to the Radiation Protection Office. This would include loss or theft of the source, mechanical shock or accidental exposure to any of the conditions in item (c).
f) - The source, or the device in which the source is used or stored, must have a radioactive materials tag stating the radioisotope and original activity, and date the source was received.
)
People using sources must wear personal monitoring devices, if the dose equivalent rate from the source or device exceeds 100 mrem /hr at one foot. The type of monitoring equipment will be specified by the Radiation Protection Office. Monitoring equipment may be required for lesser dose-equivalent rates depending upon type of use and exposure time.
The UIC must approve all locations of use.
i l
6.6 Licensed MaterialInventory and Accountability See section 6.3 for procedures for control of procurement. When laboratory supervisors receive licensed material, the data is entered into a computer database. This inventory is used to determine supervisors' and the University's radioactive materials balance. Supervisors l
annually must compare their inventory with a list supplied by the Radiation Protection Odice and report all discrepancies.
1 6.7 Scaled sources Leak-tests of sealed sources and devices, are performed at six-month intervals, or at three-month intervals for alpha emitting sources, by Radiation Protection staff or by someone trained by the RSO. Leak-tests are performed by wiping the source or the closest aixessible surface, with a moistened cloth, paper smear or cotton swab. Sources with delicate windows are not touched, but the area immediately adjacent is surveyed for contamination.
Activity of the smears is normally determined in a liquid scintillation counter, but gamma spectroscopy may also be used. The sensitivity of this method is well below 0.005 uCi. At the time of the leak-test, sources are also inventoried. Sources in storage are only inventoried, but will be leak-tested prior to being returned to service. Sources stored under security seals are not examined visually if the seals are intact. All sources are tested at least every ten years.
Beta and gamma sources less than 0.1 mci are not leak-tested, alpha emitting sources less than C.01 mci are not tested: these sources are inventoried at six month intervals.
l 6.8 Audits and Appraisals
~
6.8.1 Management and Radiation Safety Committee Audits The radiation protection program will be reviewed annually, under the direction of the University Isotopes Committee, as required by 10CFR20.1101(c). The UIC will determine the nature and scope of reviews. Records of the reviews will be retained. The RSO will also Penn State University License: SNM-95 Docket 70-113 Page 18 I
l
direct regular audits of the radiation safety program, and will implement necessary measures to correct any identified deficiencies.
6.8.2 RSO and Staff audits of user compliance Most research laboratories which are actively using radioactive material are inspected by Radiation Protection staff every three months. ' However, laboratories with very low risk use of radioactive material, such as darkrooms, may only be visited every twelve months. During these, unannounced routine inspections, laboratories are thoroughly surveyed to ensure compliance with the maximum allowed radiation levels and contamination levels. The smears are counted in an LSC with a minimum detectable activity ofless than 100 dpm/100cm. In 2
addition, laboratory staff are questioned to verify their level of training, inventory records are checked, security of radioactive material is verified, laboratory survey meters are checked for operation, normal laboratory trash is surveyed to ensure no radioactive material is being discarded to the normal trash, and all radiation postings and labels are checked.
6.9 Safety Evaluations of Proposed Uses and Usen Proposals for using radioactive materials are evaluated by Radiation Protection staff and approved or denied by the University Isotopes Committee. A principal investigator who wishes to use radioactive material must submit an Application for Use of Radioactive Materials. A copy of the current version is included to aid the reviewer in determining the kinds ofinformation required to be submitted.
In general, only faculty with at least forty hours training or experience are authorized to supervise radioactive material laboratories.
Those applying to supervise the use of radioactive material previously must have worked with radioisotopes similar to that which he or she wishes to use, and must have used that radioisotope in an amount equal to 10% of the amount to be used in the proposed project. If applicants do not have such experience, the UIC will work to ensure that the required i
radioactive material is used in a safe and proper way, Methods that may be used to ensure safety include requiring 1) increased Radiation Protection oversight, 2) work be performed under another supervisor's authorization, and 3) that certain parts of the work be performed under the control of another laboratory group. The UIC will, of course, deny or reduce the activity of the requested radioactive material, if no other method of ensuring compliance is practical.
This "10% rule" does not apply to radioactive material contained in a device such as a gas chromatograph or portable gauge.
i 6.10 Exposure Control and Monitoring
[
6.10.1 External l
l 6.10.la Radiation and Contamination Surveys Radiation surveys are, except in special circumstances, performed only by Radiation Protection staff or by reactor operators.
i Users of un-contained radioactive material are required to perform contamination surveys of their work areas after each use. The quality of these surveys is checked by the regular Radiation Protection inspections (see section 6.8.2)
Penn State University License: SNM 95 Docket 70-113 Page 19
Laboratory workers are instructed to wipe areas suspected of being contaminated with moistened tissues, paper towels, etc. to collect loose radioactive material. These wipes are then checked for activity with a radiation detector, typically a Geiger-Mueller survey meter.
Laboratory personnel may decontardinate acce sible areas that have removable contamination in excess of 1000 dpm/100 cm of beta-gamma emitters or natural uranium 2
Workers are required to decontaminate immediately any readily accessible area with transferable contamination greater than 2,200 dpm/100 cm. The allowable contamination 2
limits for alpha emitters other than natural or depleted uranium is 10% of these limits. Areas that are not readily accessible, such as the insides oflabeled centrifuges, may have removable 2
contamination levels up to 88,000 dpm/100 cm. In glove-boxes the amount of contamination allowed is limited by the radiation level on the outside of the containments '.
Laboratories with cither a history of contamination problems, or with a high potential for contamination problems, may be required to send written surveys to the Radiation Protection OfEce after each use of un-contained radioactive material.
i When Radiation Protection staff find laboratories that have repeated contamination problems, the UIC is informed. Corrective actions in the past have included:
1.
Increased surveillance by the Radiation Protection staff; 2.
Phone calls to the laboratory supervisor from UIC chair; 3.
Requiring that laboratory survey log books be kept; 4.
Requiring written surveys to be sent to the Radiation Protection Office afier each use of radioactive material; 5.
Requiring all laboratory personnel retake the basic Radiation Protection training session; and 6.
Temporary revocation of laboratories' authorization to use radioactive
- matetial, Permanent revocation of a laboratory's authorization to use radioactive material, as a corrective measure, has not yet been required.
6.10.1.b Airborne Efflueet Surveys Equipment used for air sampling will vary depending on the chemical and physical
' forms of the materials being sampled. Activated carbon filters, glass filters, membrane filters, liquid traps, or cold traps are used as necessary. Air-volume sample rates from 0.1 to 2000 LPM may be used.
6.10.1.c External exposure suonitoring Body dordmeters are supplied to people using radioactive material with exposures:
L l
Table 1 of" Guidelines for Decontamination of Facilities and Equipment Prior to Release 2
for Unrestricted Use on Termination ofLicenses for Byproduct, Source, or Special Nuclear Material", U.S. NRC, Division of Fuel Cycle, Medical, Academic, and Commercial Use Safety, Washington DC, April 1993, sets auptable surface contamination levels of 1000 dpm per 100 2
cm for beta-gamma emitters. Since these levels are for free release to unrestricted areas, requiring decontamination of a laboratory bench in a room used for radioactive work to below this levelis not practical.
r Penn State University License: SNM-95 Docket 70-113 Page 20
Exceeding an average of 0.1 mci-hour per week for gamma-ray emitters with a.
energies above 0.1 MeV.
b.
Exceeding an average of 1 mci-hr pei week for gamma-ray emitter with energies less than 0.1 MeV (includes Cr-51 due to its low gamma yield).
32 c.
Exceeding an average of I mci-hr per week for P or other high energy beta emitters.
d.
To radiographic or fluoroscopic x-ray machines.
The term " mci-hr" refers to being in close proximity to (30 cm from the body or 4 cm from the hands), or handling, a 1 mci source for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> or 0.5 mci for 2 hr, etc. Body dosimeters with a neutron monitoring TLD are supplied to pecple whose exposures may be due to neutron radiations. Finger dosimmers, along with a body dosimeters, are supplied to those 32 with exposures exceeding 1 mci-hr per week for P or other high energy beta emitters.
Dosimetry services have been provided by Landauer since 1%2. Penn State will switch to another National Voluntary Laboratory Accreditation Program (NVLAP) approved vendorif the situation warrants.
Exposures due to skin contamination are estimated initially by measuring the activity 2
present on the skin, and then using the Bq/cm to mrem / hour conversion factors to determine skin dose. These conversion factors were published by Richard E. Faw in Heahh Physics Journal. October 1992, page 447. The area of contamination is determined by placing a series of four inch square pieces of plexiglass over the affected area. The squares have holes drilled though with various (known) areas. This procedure gives a good first approximation of the extent 'of the problem. If necessary, more detailed calculations will be preformed.
l 6.10.2.
Internal exposure neonitoring l
Bioassays to determine the extent ofinternal exposure are performed if surveys indicate the possibility of an ingestion of greater than 10% of the relevant ALI (Annual Limit on Intake).
Sampling to determine the concentration of radioactive material in the breathing zone of a radiation worker is not routinely performed. The need for air sampling is evaluated in cases where dispensable radioactive material in excess of 10,000 ALIs (for inhalation) may be handled in any one year. This evaluation is only applied when the radioactive materials are used in a dispensable form.
Penn State Unwerser Licenne: SNM-95 DocUt 70-113 Page 21
- 11. WASTE MANAGEMENT 11.0 General Radioactive waste is disposed of by Radiation Protection staff. Laboratory workers put all radioactive materials into appropriately labeled waste containers. All waste is segregated, by the researchers, in separate containers for each nuclide. Exceptions to waste segregation rules may be made by Radiation Protection staff.
After waste containers have been filled, laboratory staffers provide information on the contents of each container, and contact Radiation Protection for collection. The waste is then collected in accordance with NRC and DOT transportation requirements.
7.1 Transfers of waste Any solid radioactive waste, which cannot be held for disposal by the decay-in-storage program, is transferred to a facility licensed to receive, treat, and dispose radioactive waste.
Liquid radioactive waste which cannot be poured into the sanitary sewer will be shipped as radioactive liquid radioactive waste, solidified and shipped, or evaporated and shipped (see below) as a solid radioactive waste to a licensed facility. The solidification medium used is cement-silicate, or in some cases, Ponland cement only.
7.2 Release of radioactive material to air and water.
Radioactive material is not released to the atmosphere as a standard disposal method. If disposal by this method becomes necessary, appropriate effluent monitoring is performed to quantify the release. All releases will be kept as low as is reasonably achievable.
Radioactive material is released into the sanitary sewer system in accordance with 10CFR20.2003,40CFR261 and University policies. Short lived nuclides are held for decay as long as is practical prior to release into the sewer.
There are no plans for disposal by incineration.
7.3 Waste volume reduction operations In some cases, liquid waste is evaporated, and solid residuals are then shipped as solid waste. The necessity for air monitoring will be evaluated in accordance with section 10.6.2.
l Contaminated laboratory waste may be compacted. The compactor was built by PSU l
from standard hydraulic system components and operates a 4-inch cylinder at 2000 psig. The necessity for air monitoring will be evaluated in accordance with section 6.10.2.
I 11.6 Liquid scintillation counting waste Liquid scintillation counting waste is disposed of by shipment to a licensed disposal facility.
11.9 Releases of potentially contaminated equipment Potentially contaminated equipment may be released as non-radioactive ifit meets the i
requirements given in Table 1 of" Guidelines for Decontamination of Facilities and Penn State University License: SNM-95 Docket 70113 Page 22 l
f
l Equipment Prior to Release for Unrestricted Use on Termination of Licenses for Byproduct, Source, or Special Nuclear Material", U.S. ?3C, Division ofFuel Cycle, Medical, Academic, and Comrnercial Use Safety, Washington DC, April 1993. This report sets acceptable 2
surface contamination levels of 1000 dpm per 100 cm for beta-gamma emitters. Releases will, of course, be maintained as low as is reasonably achievable.
l l
l End oflicense application l
l l
Enclosures included to aid the reviewer.
l 1.
Outline of the topics covered in the basic training session.
L 2.
Exemption from basic training request form l_
3.
Application for Use of Radioactive Materials.
4.
A Unique SubcriticalReactor-Sigma Pile by Forrest J. Remick l
j-l l
Penn State University License: SNM-95 Docket 70-113 Page 23
Enclosure Radiation Orientation Lecture Outline
- 1. INTRODUCTION Organization Senior Vice-President for Research and Dean of the Graduate School University Isotopes Committee Radiation Protection Office Regulations and Licenses Nuclear Regulatory Commission 10 CFR 19 10 CFR 20 NRC-3 Pennsylvania Bureau of Radiation Protection Rules and Procedures for the Use of Radioactive Material at the Pennsylvania State University Radiation Protection Office Location Phone Staff Radiation Safety Orientation Requirement Faculty Staff Students
- 2. RADIOACTIVITY Activity (curie, Becquerel)
Half-life (physical, biological, effective)
- 3. TYPES OF RADIATION Demonstration / Discussion ('H, "C, 32P, "S, "Ca, Cr, "Sr, i2si, in,, 2iopo) e Alpha Particle Charged particle (directly ionizing)
Energy (several MeV) l Monoenergetic i
Range (several cm.)
L Beta Particle Charged particle (directly ionizing)
Energy (kev to MeV)
Polyenergetic Range (mm to several meters)
Exponential attenuation i.
Gamma Rays Photon (indirectly ionizing)
Energy (kev to MeV)
Monoenergetic l
Penn State University License: SNM-95 Docket 70113 Page 24
Exponential attenuation Neutron Neutral particle (indirectly ionizing)
Energy (thermal to severalMeV)
Monoenergetic Exponential attenuation
- 4. DEFINITIONS AND UNITS Exposure (Roentgen)
Absorbed dose (rad and gray)
Effective Dose (rem and sievert)
Radiation weighting factor Tissue weighting factor
- 5. BIOLOGICAL EFFECTS OF RADIATION Acute effects Whole Body Skin Chronic delayed effects and risks Somatic Genetic
- 6. OCCUPATIONAL DOSE LIMITS Total effective dose Organs Extremities Skin Annual Limits ofIntake(ALI)
Derived Air Concentrations (DAC)
Embryo / fetus Minors Unrestricted area
- 7. POPULATION DOSE Natural Medical Other
- 8. PERSONNEL MONITORING
{
Dosimeters, TLD, whole body, extremities, skin j
Sensitivity Rules for use j
Bioassay Estimated dose Low energy beta emitters
- 9. PRINCIPLES OF RADIATION PROTECTION Time Distance i
Penn State University I.icense: SNM-95 Docket 70-113 Page 25 I
L-----_---
Shielding Containment Radioactive material Personnel Surveys Radiation Contamination Fixed Transferrable ( Wipe Smear )
- 10. WASTE DISPOSAL Solid Half-life Animal Hazardous waste Liquid Half-life Aqueous Organic Liquid scintillation fluid
- 11. LABORATORY RULES Purchases (form HP-10)
Receipt survey Inventory form Transfers On campus Offcampus Disposal record Use of gloves Use of syringes / sharps Ponable shields Double containment Transfer pipets Frisking and wipes / smears at conclusion of work i
Decontamination Security Food in radioisotope laboratories
]
- 12. SIGNS AND LABELS I
Rooms Containers Packages j
- 13. SECURITY Rooms
- 14. EXPERIMENT DESIGN Counting data 1
Penn State University Licenac: SNM-95 Docket 70-113 Page 26 l
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E_____________
I
Transfer estimates Starting activity Choice ofisotopes Chemistry ofisotopes (solubility, reactivity, effective half-life, physical form)
- 15. EMERGENCIES Contamination Medical emergencies 1
I 1
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Penn State University License: SNM 95 Docket 70-113 Page 27
Penn Stata Univtrsity University isott. pes Committee Application for Exemption from UIC Training Requirement Penn State University regulations require everyone who will be using radioactive material to attend a radioactive materials training program prior to beginning work. The University isotopes Committee recognizes that this may be impractical for some short term workers at PSU. Exemptions to this I
training requirement may be given, by the UIC, if the worker can document that he or she has had extensive experience and training at another institution.
Specific Radiation Protection training is not required for persons working under the direct supervision of an authorized radioisotope user. If a training session is held during the applicant's stay at PSU, the applicant may be required to attend the lecture.
Complete the items in the form below, as indicated. use as much space as required for each entry. St bmit the form to Radiation Protection, e Eisenhower Parking Deck for review. Forms are to be typewritten.
- 1. Supervisor:
Authorization No.
Expiration Date:
Padiaton seetv oniv Receivea:
Address:
Email:
Telephone:
- 2. App!icant for whom the exemption is requested:
Name:
University status:
email address:
Arrives at PSU on:
Leaves PSU on:
- 3. Radionuclides and activity that the applicant will be using.
Radionuclides Typical activity to be used Physical Generic chemical form' at any one time (mCif form'
' Typical activity The activity that you expect the applicant to use at any one tame.
8 Physical form - solid (S), liquid (L), gas (G), sealed source (sS), plasma (P)
' Chemical form - nucleotide, methionine, acetate, activated metal, etc
- 4. Previous training: Ust specific formal training the applicant has had dealing with radioactive material. Please provide documentation from the Radiation Safety Office at other institutions.
Penn State University License: SNM-95 IAx:ket 70-113 Page 28
- 5. Experienc:: D crib he appucent's aW.vant expwienos with redoactive mztwid.
- 6.' Applicant's signature:
! have used radioactive material and been trained in its use as described above. I am familiar with Nuclear Regulatory Commission regulations relevant to my use of these radioactive materials at PSU.
Signature of applicant:
date:
.7. Supervisor's signature:
I am responsible for the actions of all persons working in my laboratory under my PSU authorization.
I will instruct the applicant in the safety procedures required for his or her use of radioactive material at PSU.
Signature of supervisor:
date:
- 8. Radiation Protection recommendation
_ No orientation is scheduled for the time that the applicant will be on campus.
_ Applicant must attend the orientation scheduled for Comments:
_,, Approval of exception recommended.
Radiation Protection:
date:
- 9. University Isotopes Committee approval. Chair, or vice-chair in chair's absence, may approve this request prior to notifying the rest of the UIC of his or her action. Please notify the supervisor of the approval or denial as soon as possible. Retum form to Radiation Protection for filing.
L This exemption expires on
, no more than sixty days from the date of this approval.
Approved by:
date:
[
This form approved by UIC on December 18,1997.
l e:Wohtes\\Trommgauc Penn State University License: SNM-95 Docket 70-113 -
Page 29 o___________________
Penn State University University Isotopes Committee Request for Authorization to Use Radioactive Material Complete the items in the form below, as indicated. Use es much space as required for each entry. Submit the form to Radiation Protection,6 Eisenhower Parking Deck for review. Forms are to be typewritten.
- 1. Applicant:
Authorization No.
Name:
Expiration Date:
License No.
Department:
Regulatory Compliance Number College:
- 2. Acidrosses: Office Email Campus Mail:
- 3. Telephone (s) Office:
Laboratory:
Home:
e
- 4. Type of application: en.ca.nin.esiv.
_ New, research
_ Renewal of current authorization #
_ New, classroom only
_ Amendment to current authorization #
_ New, seated source (s) or device (s)
- 5. Radionuclides and activity List all of the radioisotope (s) and the activity to be covered by this authorization, in general, list all isotopes that will be used in your research on this one application. The generic chemical form may be used.
Radionuclides Possession Typical activity Physical Generic chemical form
- Umit (mci)'
per order (mci)'
form 8
' Possession limit-the maximum activity permitted in your laboratones at any one time, NOT includmg the activity in the waste containers. This should probably be no more than 5 times the amount you expect to purchase at any one time.
~
' Normal activity per order - The activity that you expect to order for use in the laboratory.
8 Physical form - solid (S), liquid (U, gas (G), sealed source (SS), plasma (P)
- Chemical form - nucleotide, methionine, acetate, activated metal, etc
- 6. Location List all rooms where radioisotopes will be used and describe the facilities, such as sinks, hoods, cold rooms, counting rooms, darkrooms, etc.
Room Building Intended u:;e L.m e.nen.a..
Facilities Hoods, einks, eto I-l
- 7. Personnel Ust all persons, and theer email addresses, who are permitted to reouiva and use radioactive material under this authorization. All perseas listed must have completed radioisotope safety training at PSU prior to beginning; work with radioactive material. When someone new starts working in your laboratory, notify Radiation Protection.
Penn State University License: SNM-95 Docket 70-113 Page 30 i
Name University Status email address (Faculty, staff, post-doc, etc) l
- 8. Proposed use(s) Briefly describe the proposed use(s) of the radioactive material.
- 9. Procedures Describe the experimental procedures which involve radioactive materials. The procedures should be in sufficient detail for the reviewer to determine the amount of radioisotope and other reagents used (this is needed to determine the arnount and composition of the waste from each experiment). The description should also indicate the precautions to prevent contamination and radiation exposure of personnel. If airborne radioactive material can be produced (powder, vapor, gas, aerosol),
describe the procedures and facihties that will be used to control the airbome material. The radioisotope user is required to routinely survey his/her work area for contamination using a survey meter plus wipes and/or smears. // you W/// be us/np a Standard publishedprocedure, p/ ease attach a copy.
- 10. Radiation detection equipn ont List the equipment that is available to detect radiation and radioactive contamination. Include the type of ins rument, manufacturer, model, and range (cpm or Mr/hr) for all instruments. All laboratories, except those using only tritium, are re tuired to have a portable survey meter in that laboratory any time radioactive material is used.
Therefore, shared portable survey inst uments are not acceptable. Laboratories using tritium must have a liquid scintillation counter available, but not necessarily located n that laboratory.
Type of detection equipmeiit, and Manufacturer Model Type of Range of location Probe detector LSC in room Auto-gamma in room I
Portable survey meter in
)
I j
- 11. Waste disposal The radioisotope user is responsible for preparing, segregating, labeling and storing ali radioactive waste according to the procedures established by Radiation Protection. No radioactive waste may be released to the sanitary sewer, the hood or the normal trash container in the lab. Release to the sanitary sewer from washing dishes is limited to o.1 uCi/ day. In the table below estimate the volume and the activity of the waste to be generated.
-s Waste type Volume (gallon / month)
Activity (mci / month)
Solid (paper, plastic, glass)
Liquid (aqueous)
Liquid (organic) l Liquid scintillation vlais l
l Animal carcasses I
other Penn State University 1.icense: SNM-95 Docket 70-113 Page 31
11.1. The use of the hazard:us chemicals listed below should be svoided if possibb. If thess chemicals are required for your research, each must be discarded into a separate radioactive waste container to minimize the total volume of radioactive / chemical waste that will require special handling.
Radiation Protection staff will gladly assist in finding special waste containers and shielding to fit your
'needs. 'The hazardous chemicals to avoid include, but are not limited to:
Acetonitrile Benzene Carbon tetrachloride Chloroform Chromium Formamide l'honoi Thimerosal (Hg) l non-soluble, non-biological materials pesticides l
I will be using some of these hazardous compounds in my radiological research, and will request l
special containers from Radiation Protection for their storage. (Please circle the ones that you know you will be using.)
List all the chemicals that are used in your experiments that wili be in the liquid radioactive waste. List l
the full name of the chemical, not just the chemical symbol or abbreviation. For buffers and other Wutions, list all the chemicals, not just the name of the buffer.
11.2. Because radioactive pathogen waste or recombinant DNA waste are biological as well as radiological hazards, both sets of regulations apply to this waste. All liquid radioactive waste containers that will contain biological waste must contain at least 10% bleach solution (based on final volume) to inactivate pathogens and prevent microbial growth during storage. All solid radioactive waste containing bio-hazardous material must be sterilized in an autoclave prior to placing the material into the solid radioactive waste containers provided by Radiation Protection.
I will not be using any of pathogen waste or recombinant DNA waste in my radiological research.
I will ensure that 10% (final concentration) bleach is added to all aqueous waste containers that will contain biological waste prior to adding biological waste to the container.
I will ensure that all solid pathogen radioactive waste is sterilized prior to placing the radioactive material into the solid waste container.
11.3. Because radioisotopes in animals may pose special disposal problems, additional handling and preparation in the laboratory may be required, in addition, because waste disposal may be difficult or expensive, producers of high-activity animal waste may be charged for the disposal of the waste.
I will not be using radioactive material in live animals.
I will be producing radioactive animal waste as follows:
- 12. Training Personnel, listed above, who will be usma redoactive matorisie in your laboratory must have been trained by Radation Protection, and have passed the exam. What additional training will you provide?
X New personnel will be trained by me or by one of my senior trained personnelin the safe handling of radioactive material, in the use of survey meters, how to perform wipe or emeer tests, how to maintain inventory records, how to prepare radoactive waste for pickup, and how to maintain proper security of radioactive materiale.
Personnel performing lodnations or using more than 5 mci of "P at one time will be trained by me and then will arrange for specific laboratory training by Radiation Protection.
My laboratory requires a vehicle to transfer radioactive material between research locations, I will arrrnge to have personnel trained by Radiation Protection prior to having anyone perform such a transfer.
This radioisotope is used me part of an approved class. Training of the ciaes by Radiation Protection will be requested.
Long term radioactive-animal caretakers will need to be trained by Radation Protection.
Addtional training specific to this authorization includes:
- 13. Security of radioactive material You are responsible for providng security adequate to prevent the unauthorized removal of radioactive material" from any location where you and your staff use redonctive material. Explain how your eeourity will be maintained. The method (s) listed below may be changed without ulC or Radiation Protection approval as long as security le
- property maintained.
Laboratory door (e) will be looked at all times, even when room is occupied.
All radioactive material will be escurely loc 6ed except when it is in use. It will be ender droct supervision at all times when tha room is not locked.
Room will be locked when lab personnel are not present.
Other:
. Penn State University License: SNM 95 lhx;ket 70113 Par 32
- 14. Exemptions if you are requesting a special exemption to normal UIC policies, or if you wish to contirrie an exemption previously granted by the UIC, explain your request. Include a copy of any supporting documents. An example would include speciallaboratory arrangements that allow food consumption in a part of your lab.
- 15. Restrictions This section will be completed by Radiation Protection or the University lootopes Committee prior to approval.
- 16. Applicants statement The applicant is responsible for Insuring that allpersons using radioactive matedal under this authodzation have been adequately trainedin the procedures usedin the laboratory and are aware and agree to comply with the University Rules and140cedures for the Use of Radioactive Matedal.
Radioactive materialis only to be used as described in this authodzation and in the locations listed above. No use of radioactive matedalin humans orin field releases is permitted. Allprocurement, transfer or shipment of radioactive material, except as specifically authodzed, is to be done through Radiation fVotection. Experimenters are responsible forperforming routine contamination surveys and the immediate decontamination of contaminated areas. The University Isotopes Committee reserver the right to revoke or cancel this authodzation.
I understand the conditions of this authorization and agree to comply with the University Rules and Procedures for the Use of Radioactive Material.
by Date
- 17. Radiation Protection recommendation for approval by
- 18. University lootopes Committee rpproval Date by Date Optional. Purpose of research Please describe in broad general terms, suitable to a person NOT in your field, why this research is interesting, and what you hope tv discover or develop. One or two brief paragraphs should be sufficient. This le for information only, and is not part of your appiieetion. it will mainly be used to explain to people who do not work with radioactive motorier, why radio.oiive meterial se needed en compu..
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Penn State University 1.icense: SNM 95 Docket 70-113 PaFe 33 l
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First Time Applicants Only First time applicants must satsfy educahonal, training and experience requirements before they will be permitted to act as a Radiation Laboratory Supervisor, Please provide the following information identifying the formal training and experience you have in the specific topics listed below.
Formal Classroom Education or Training.
Topic University /conege or conm neme course Tme Course length in and address where you received hours or numtw educahon or training.
of credNs.
Gewel principios of radioectMty and remoscove materiais charactertebes and typn ofionWng redshon Units of redishon does and radioactNo motories quenimes Redemon delection instrumentebon 1
Biological hazards and enacts of moosure tolonWng re General principios of redishon protechan practices Radiation Detection Instrumentation.
Ust eachinstrument esperately Uruversity/ College or company name Type of work performed Years of (GM survey meter, liquid scintillebon and address where you gained (contaminehon surves, semple expenonce counter, gamme spectroscopy, etc.)
expertence with the Instrument enelysis, etc.)
Please identfy the types of dispersible radioactive materials, sealed sources or radiation generating devices you have experience working with, and the type of work performed.
Isotopes and/or Univoreny/couege or company name Type of work performed ActMty of Years of exponeru devloes used.
and address where you gened (DNA labehng. gol electrophoreas, isotopes used.
(listindMdueny) aportance woridng with these redmiodinehone, x<ey (mci) maertais.
crystenography.e:.)
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I Penn State University License: SNM-95 Docket 70-113 Page 34
'c ueuw c;osce mutaminY LICENSE SNM-95 RENEWAL
,=
A UNIQUE SUBCRETEC/ L cw-REACTC2-SIGMA PILE FORREST J. REMICK The Stoic University of Pennsylvania INTRODUCTION
- The advantages of the suberitical reactor and the sigma pile as pedagogical devices are well known and have received attention throughout this conference. Their use as tools for the edu-cation and training of nuclear engineers was demonstrated quite early at the Oak Rid;e School of Reactor Technology,3 at the Argonne School of Nuclear Science and Engineering,8 and at' several universities.3 Because of this demonstrated usefulness and also because the State University of Pennsylvania was engaged in teaching nuclear engineering to foreign engineers s
and scientists in a branch of the International School of Nuclear Science and Engineering, it-was deemed advisable to supplement the reactor laboratory portion of this program by the addition of a subcritical reactor-sigma pile combination. Prior to this a swimming pool re-actor, in operation since 1955, was the only nuclear multiplying system used in the reactor laboratory program at the State University of Pennsylvania.
In 1957 the design of a suberitical reactor-sigma pile combination was undertaken.' A graphite-natural-uraniurn type assembly was selected because of its adaptability to student.
experiments resulting from relatively large neutron-transport distances. Funds for the con-struction of this assembly were provided'by the U. S. Atomic Energy Commission as a part of its Equipment Grant Program. The construction of the assembly was completed in early 1958, and it has proved to be an e>.1remely valuable educatient.1 tool.
DESIGN The criteria for the design included that (1) the assembly should be a combination sub-critical reactor and a sigma pile so that the natural-uranium fuel could be removed and the resulting vacancies filled with graphite stringers; (2) the assembly should be of sufficient size to provide an extensive region over which a exponential flux variation could be observed; (3) l the assembly should be so designed that several fuel loadings would be possible near and at the optimum ratio of Iuel and modcrator but providing cases of both over and under modera*
~
tion! (4) the assembly should be capabl.e of being pulsed by use of one of the horizontal beam i
ports of the swimming-pool reactor; and (5) the location of the source plane, as well as the position of the neutron source or sources in the source plane, should be capable of being -
' varied.
To be able to pulse the assembly with a horizontal beam port from the swimming-pool-reactor, it was decided to make the axis,.which is perpendicular to the source plane, hori-zontalin contrast to classical assemblies of this type in which this axis is vertical. Thus in-89 35
'ste:.d of 1:;e no. : Nv being built on tisp of a moderating peden;d, it is placed on its side with the pedeMM urs...n;: ca.e end of the abacmbly. To avoid building nn expensive and cumbersome gamma shield nrUund this exposed pedestal, the use of plutonium-beryllium neutron sources was planned for the design. The decision to build the assembly on its side, so to speak, has l
proved to be a tremendous asset in its classical use and its adaptability to use with the port-
, able neutron generators currently available commercially. The assembly is shown conceptu-ally in Fsg.1.
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During the early stages of the design, it was known that natural-uranium-fuel rejects
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would be available for use, but it could not be determined whether they would be solid or l
hollow fuel slugs or what the actual diameter would be. Therefore, in the design four separate fuel sizes were assumed based on the best information available in the unclassified literature about typicnl natural-uranium fuel-slug dimensions. These fuel radii were 1.27 cm (1.00 in.
in diameter), 3.33 cm (1.045 in. In diameter),1.40 cm (1.10 in. In diameter), and 1.43 cm j
(1.125 in. In diameter).' The detailed analytical design is described in reference 4 to this paper.
Both the effect of air gaps and the absorption due to the aluminum cladding on both hollow and l
solid slugs were incorporated in the calculations. The results of these calculations for the t
solid-fuel-slug case appear briefly in Tigs. 2 to 4, where R is the solid-fuel-slug radius and j
R is the lattice equivalent-cylindrical-cell radius. The hollow-slug case is iiot considered of l
3 Interest in this paper because solid slugs were eventually supplied for the assembly.
In the early stages of the design of the reactor, it was desired to obtain graphite bars that i
would be approximately 70 in. in length. Only 3 of Il graphite suppliers contacted could manu-I facture reactor-grade graphite, and only one of these claime:! the capability of supplying bars i
of the desired length. However, during the final stages of this design, the supplier declined l
the original offer of supplying graphite bars in 70-in. lengths. B,ecause all three suppliers were j
capable of manufacturing bars in lengths in the general range of 51 to 54 in., the final design j
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was based on two bars of lengths of 52V and 17P In; as a means of obtaining the desired 70-in.
length. These particular lengths were selected as a means of reducing machining waste and thus the over-all cost. The 52Y-in. lengths were readily obtained from 54-in.-long rough bar stock. Similarly three 17/8 -in. machined bars were obtained from 54-in.-long rough bar r..
stock without unusuable short lengths remaining.
The reactor design in which two graphite bars must be used to obtain the desired bar length is not the most desirable design because in fabrication and lattice changes it is neces-sary to handle approximately 25 per cent more pieces. However, the decreased weight per bar offers some advantage in assembly.
The assembly lenglh,Js 104 in, and two separate bars each 52 in. long are used. By the method of laying these bars crosswise relative to those bars containing fuel openings, no other keying or supports are required for the assembly.
The only sizes of rough bar stock orig;inally available were 4.37 and 4.50-in squares. The maximum sizes of machined bars obtainable from this rough' stock are 4.00 and 4.33-in. square e~
bars. later in the design period, rough bar stock in larger sizes became ava!!able through the previously mentioned suppliers.
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From the early design calcuintions in which data on the fuel slugs provided by the Atomic l
Energy Commission (1.27 < R < 1.43) were used, it became obylous that the use of bars in sites cf 3.50 by 3.50 in and 3.50 by 1.75 in, would provide four separate lattices with k.,, > 1 and thit the values of k. v ould be distributed fairly uniformly around the optimum condition.
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However, because of the waste involved in machining the available bars of these sites, the calculations showed that approximately 3,0 per cent more rough grapatte stock would be re-quired than would be required if the 4.00-in. bars were used for the proposed reactor and that the machining cost would be increased more than 30 per cent because, in addition to more bars
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- being used, each bar would require more machining. The cost of a reactor with these smaller bars was therefore found to be too expensive. It was found that 4.00- by 4.00-in. machined bars would require the minimum number of rough bars and the minimum amount of machining and would provide five separate lattices with k.> 1 and that, although values of k. would be obtained on both sides of the optimum condition, none would be very near the optimum condition. In facj two' separate' sets of the points wculd so closely coincide that, in effect, only three di!!erent lattices with*k.> 1 would result if these bars were used.
However, further investigation resulted in the selection of bars 3.88 by 3.88 in.' and 3.88 by 1.875 in. These sizes are a compromise of the advantages and disadvantages of the 3.50- and 4.00-in. sizes. Although these bars require more rough stock and machining than the 4.00- by 4.00-in. bars, the estimated cost was within the funds available for the graphite and its machin-j ing cost (S29,500). These bars offer five separate lattices with k. > 1. 'One of the points
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j essentially coincides with the optimum condition. Although the remaining four points are dis-i tributed with one point below and three points above the optimum condition, they are so spaced that this is not a serious disadvantage. For these reasons the bar sizes of 3.88 by 3.88 in. and 3.88 by 1.875 in. were selected. It is pointed out that, in addition to these five lattices with k.> 1, innumerable lattices exist where k., < 1, especially for lattices that are overmoderated.
8 Each fuel slug is 8/g in. long, and elght of these slugs are placed in a fuel channel. This I
gives a fuel-channel length of 68 in. Because of the manner in which the reactor is constructed, it is necessary that the width be some multiple of 3.88 in. Eighteen of these bars, the number that constitutes the total bar width, have a width of 69.84 in. Therefore, with allowances for tolerances on width and bar warpage, the width of the reactor was made to be 70 in., as pre-viously mentioned. The eight fuel slugs in a luel channel are loaded into a 6061-T6 aluminum -
7 tube that has an outside diameter of 1/ in, and a wall thickness of 0.058 in. This method of 8
loading expedites the changing of fuellattices since eight slugs can be handled at one time.
The added aluminum present in the cell from this tube increases the absorption of neutrons, but this absorption does not appear to be excessive. These tubes can be readily plugged and water filled to observe the effects of a water coolant for the fuel slugs if desired.
The two rnajor loadings possible with the assembly are shown in Figs.1 (Leading 1) and 5 (leading 2). The three separate lattices with k. > 1 usable in Loading I and th: tro lattices with k. > 1 usable in Loading 2 are shown in Fig. 6. loading 1 is in the most gens al use since it offers a point near optimum condition and points below and above optimum cell size.
The information pertinent to the dimensions of these various lattices is contained in Table 1.
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Table 1-CELL CEOMETRES Fuel to fuel Ce'll-radius leading Ceil M '.
Volume of moderator designation geometry Cm In.
Cm In.
per em of length, cm3 1-A Square
- 24.6 5.76 8.26 3.25 -
200 1-B Square 29.2 11.51 26.52 6.50 842
,. j 1-C Nemagonal 20.7 8.14 21.67 4.60 413
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2-A Square 29.4 7.63 20.95 4.31 362
- i 2-B Heaagonal 27.4 10.79 25.47 6.10 737 1
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The different type ;;raphite bar.* which are required to provide two separs;e suL:ritical loadir.gs with five separate lattacca are shown in fig. 7. Table 2 provides information about the number and actual dimensions of all these bars.
Tal.lc 2-CH4PHITE BAR REQUIREMENTS Number Tmc bar required A
B C
D Detatl A
22 3.b5 3.66 52%
A bar AA 22 3.4 3.66 17 %
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A-3 17 3.E6 3.66 52%
1.50 x 1.50 A-3 bar AA-3 17 3.66 3.86 17 %
1.50 x 1.50 A-3 bar A-4 1
3.65 3.65 46.56 1%D x 1.80 A-4 bar 2%D x 1.80 A-5 2
3.65 3.65 46.56 1%D x 3.305 A-5 bar j
A-6 1
3.65 3.65 23.44 1%D x 1.60 A-6 bar A A-6 2
3.65 3.65 23.44 1%D x 3.305 A-6 bar 1
B 462 3.66 1.675 52 B bar l
. B-1 220 3.86 1.675 52%
B bar BB-1 220 3.66 1.675 17 %
B bar B-2 4
3.66 1.675 52 1.50 x 0.755 B-2 bar B-3 2
3.65 1.644
$2, 1% x 1.644 B-3 bar C
2 1.45 1.45 52 C bar C-1 171 1.45 1.45 52%
CC-1 171 1.45 1.45 17 %
C bar C bar The assembly is covered with sheets of cadmium to guarantee the b' re boundary condi-a tions assumed in the analytical design. To provide strength to the 0.020-in. cadmium used, it is sandwiched between two riveted aluminum sheets that are each 0.063 in. thick. An actual photograph of Leading 1 is seen in Fig. 8, and the assembly with its cover is shown in Fig. 9.
Eighteen foil-stringer positions are present which have hinged cadmium-lined trap doors through the outside covers, and there are eight source bars that are machined slightly under-size in order that essentially any source configuration utilizing from one to five plutonium neutron sources can be used.
Several alternatives were possible to provide openings in the graphite into which the fuel co'ld be inserted. One method is to drill holes from either end of the graphite bars, which is u
very expensive and which usually allows a slight offset from tool wander" in the center where the two drilling tools meet. Another methoiis to chamfer the edges of four adjoining graphite bars. This is a rather simple operation, but it requires four separate setups per opening.
Cost estimates indicated that it would be cheaper to machine a square 1.5-in. corner off the square bars. Cut for cut this is more expensive than chamfering the edges, but because only one-fourth as many cuts need to be made, this method is substantially cheaper (approximately 50 per cent, according to the supplier) than both the drilling and chamfering procedures. By the procedure of removing the fuel slugs from these openings and replacing them with graphite-stringer inserts, a complete graphite sigma pile is obtained for use in measuring the graphite diffusion length, the age, and for pulsing experiments. The sigma-pile loading is shown in Fig.
10.
Special graphite stringers have been fabricated for holding indium foils with thtn aluminum l
backing, minute BF and fission chambers, etc. Several of these stringers are shown 2.: Fig.
- 11. Also in this f.;ure, viewing from the top to the bottom of the figure, the following struc-g'5-4, l
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tures can be seen; the aluminum tube that holds eight fuel slugs; the graphite stringer that I
holds a plutonium-beryllium source in one end and slots for cadmium-covered indium foils for age measurements; the two halves of the graphite stringer that contains a minute BF counter in its aluminum protective cover; a small graphite stringer that holds indium-aluminum foils for extrapolation-distance measurements; cadmium boxes for foils; and a canned cylindrical fuel slu;;.
i Because the assembly is horizontal, it is a simple matter to conduct an exponential ex-periment without the need of climbing on top of the assembly or without the need of winches, etc., to position the detector. In addition, since a through-hole exists along the transverse axis (perpendicular to the source plane), the, detector can always be followed by calibrated graphite stringers that indicate the detector position and prevent neutrons streaming out of the hole. Graphite stringers are provided which enable the flux to be plotted near the assem-bly boundaries in order that the extrapolation distance can b2 readily obtained. The special
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stringer that contains a plutonium-beryllium source and numerous cadmium-covered indium i
foils is inserted in the }ransverse axis so that the source can be positioned in the center of the sigma pile for age measurements in an infinite moderator or offset from the center if the l
effects from the use of a finite moderator are to be observed.
6*
UTILIZATION s'
The suberitical-s,lgma pile assembly described in this paper has proved to be a valuable f
tool for teaching reactor faboratory courses. It also has proved to be quite flexible, being readily converted from one suberitical fuelloading to another in about half a man hour or to a j
sigma-pile configuration in about two man hours.
1 1
As a sigma pile the assembly is used to compare measured flux plots along all major axes.
with the calculated distribution, to measure diffusion length, extrapolt. tion distance, Fermi i
Age, and to observe flux distribution as a function of source configuration or as a function of the position of absorbing material in the assembly. A typical student experiment conducted j
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t'ith the sigma pile is included as Appendix ! to this pa-__-_-- _ _ - -- - - - - -
diffusion. length experiment are given.
pes. In Tig. 23 the plotted data of a f
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o Go 120 tBo 24o otsTANcE FRoM sQU4cf PLANE CM Fig. 32-Diffusion length in graphite experimen't.
O. data points. A, least squares fit.
i 1
1 As a suberitical Ieactor the assembly'is used to measure extrapolate sion icngth in the suberitical assembly, infinite multiplic on distance and mate-ge and diffu.
.l abilities, effective multiplication constant (k rr), and suberitical multiplicati eakage prob-
{
measured and calculated for various fuel to moderator lattices e
on. All these are t
near the optimum value for k for the particular fuel size. I
. One of the most effective ex-I l
, which is kg of natural uranium are in the assembly. In a following experiment th approximately 1195 8
ditional 1195 kg into the assembly by removing the remaining graphit l
e students insert an ad-They find that in this case k is much lower than with the previous loadie stringers (see T
[,
in Fig.13 the results of a typical exponential experiment with le ng containing half as j
quite effectively.
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ng 1-C are shown.
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SUMMARY
l reactor.-sigma pile has proved to be a valuable' laboratory ed j
assembly, which is approximately 6 by 6 by 9 ft. is readily converted from research tool. The a sigma p!!e to a l
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io, cool.
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2 s
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(
l 5
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5
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t
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h Tig.13-Exponential experiment x,
l data points. A..least squares fit.
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i 1
suberitical reactor. As a subcritical reactor, five lattices with k greater than unity are avall-able. These lattices provide conditions near the optimum fuel to moderator ratio for the partie-
+
ular fuel slug (1.30-cm radius) as we!! as lattices that are under and over moderated.
The assembly is u,niquely positioned on its side in comparison to the classical position of j
similar assemblies. This adds to the flexibility of the assembly and makes it readily adaptable to pulsed or continuous neutron-source experiments in which either horizontal beam ports from other critical assemblies or separate neutron generators that are currently available commercially are utlitzed.
?
REFERENCES -
- 1. Oak Ridge School of Reactor Technology, Tennessee, Reactor Physics Laboratory Manual, i
USAEC Report T1D-5262, July 1955.
- 2. A. B. Smith, An Experimental Study of Heterogeneous Exponential Assemblies, USAEC Re-port M-6246 (Includes TID-5025), School of Nuclear Science and Technology, Lemont, Ill.,
June 1955.
- 3. L. B. Borst, Suberit!Eal Reactor in a Pickle Barrel-NYU's Training Tpol, Nucleonics, 14: (8), 66-68 (August 1956).
i
- 4. F. J. Remick, A Graphite-moderated Suberitical Reactor-Sigma Pile, M.S. Thesis, The State University of Pennsylvania,1958.
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