Jefferson Lab > EH&S > RadCon
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Frequently Asked Questions

Pregnancy and Medical Concerns
ARM/Accelerator Operator Related


Q: Where can I get information on my lifetime dose?

A: Dose records for all individuals issued dosimetry are available from the RadCon Dosimetry Office.  For official dose history request, contact Becky Mosbrucker at x7236 or log onto the dosimetry page from the RadCon home page to access your annual report (  Dose records from previous employers may be available, depending on the level of cooperation of individual previous employers in transmitting dose records from their facility to Jlab.


Q: Do I need a dosimeter to enter a controlled area?

A: No. Access to a controlled area requires GERT or a GERT-qualified escort.  A dosimeter is required for access to radiologically controlled areas (RCAs).


Q: Why do I have to keep my dosimeter at work? We could take them home at other labs I worked at.

A: The DOE RadCon Manual forbids DOE Labs established after 1992 from establishing a dosimetry program that allows the use of dosimeters off DOE premises. If a dosimeter is kept at home, the background level may be slightly different than that at Jlab and inaccurate dose corrections could be made.  In addition, it is apparent from years of experience, that labs that allow dosimeters to go offsite have a higher dosimeter loss rate, which leads to more dose investigations, which are costly, time consuming, and result in only a rough estimates of actual dose received.


Q: I lost my dosimeter. What do I do?

A: Contact Becky Mosbrucker at x7236 in order to complete an Investigation Report-information will need to be collected from you to ensure that your radiation dose records accurately reflect the radiation dose you received. You may be issued a spare/temporary dosimeter dosimeter until your original one is found.  If your original dosimeter is found, please return it to RadCon.


Q: Is there a way to get a dosimeter rack for my building or to change an existing location within a building?

A: If you have a group of 20 or more people who are in agreement with the proposed rack change, present the request to Becky Mosbrucker at x7236.


Q: I want to have my dosimeter housed in a different rack. What do I do?

A: Contact Becky Mosbrucker at x7236.


Q: How should I wear my dosimeter?

A: Your dosimeters should be attached to an article of clothing in your torso area (i.e., not on a lanyard which moves around, and not at the waist).  It should also be worn with the name side facing outward.


Q: Why can't I attach a dosimeter to my lanyard?

A: The portion of the dosimeter which measures neutron exposure necessitates continuous close contact to the human body.  Wearing the dosimeter "away" from the body causes the dosimeter to not function as intended and may produce false low readings.


Q: I just completed the GERT and/or Radiation Worker I test, when will I have access to the accelerator site? When will JLIST be updated?

A: JLIST is updated periodically (twice a day). You may not have site access until JLIST is updated.


Q: As a regular employee, can I take the Radiation Worker I test at the User Liaison's Office?

A: If it is more convenient, and the User Liaison's Office approves, this is acceptable. You may also take the RWI test with the receptionist at the Support Service Center (SSC- formerly known as the VARC – Building 28).


Q: Can I take a paper test for Radiation Worker I training?

A: Yes.  Paper exams, however, are only available within the RadCon Department. Note: this policy may change as we migrate to a new testing scheme.

As a reminder, you are required to review the RWI study materials (online course or handout) before taking the exam.  You can find the study materials at this website (SAF801C)


Q: What are the prerequisites to Radiation Worker II testing/class?

A: Before taking the RWII training, you must be RWI qualified. You should also request approval from your supervisor to take the course.

Q: Can I take the Radiation Worker II test without attending a class?

A: Not if this is an initial qualification.  The RWII class is designed to teach people how to work in potentially contaminated areas and/or with potentially contaminated items and a portion of the class is dedicated to proper techniques for dressing in and out of anti-contamination clothing.  This information cannot be adequately conveyed through a self-study and a written test.


Q: Where can I sign up for the Radiation Worker II class?

A: Call or email David Hamlette at 876-1743.  When there is a group of at least 5 individuals, a class will be scheduled.


Q: When is the next RWI class? When is the next RW II class?

A: The RWI class (SAF801C) is available online at or you may use this study guide.
 In-person classes for RWI and all RWII classes must be set-up by contacting David Hamlette at 876-1743.  When there is a group of at least 5 individuals interested, a class will be scheduled.

Q: Are there shorter/refresher classes available online?

A: No.  There currently are no condensed refresher courses available for RWI or RWII.  However, when reviewing materials using the study guides or online content, it is ok to only review materials you feel less comfortable with.  In addition, the practical portion of the initial training is not required for requalification.


Q: What are the Radiation Worker training requirements for Users?

A: Radiation Worker training is required for regular unescorted access to radiologically controlled areas (RCAs).  Though some departments/divisions have blanket policies regarding training requirements for their employees/users, RadCon generally encourages careful assessment of actual access needs before choosing a training level (for example, access to the accelerator site alone does not require RWI qualification, only GERT). 


Q: I'm a user preparing to come to Jlab. How long will it take to get my Radiation Worker I qualification?

A: You can prepare for the test/practical ahead of time by completing the online training (SAF801C) or reviewing the study guide (approximately 3 hrs to complete). You should also read/sign the General Access RWP (SAF801kd) and fill out a dosimeter request.  Once you arrive onsite, you can take the written exam at the RadCon office (Bldg. 52), at the Support Service Center (Bldg. 28), or at the User Liaison Office in (CEBAF Center – Bldg. 12).  Finally, you must schedule the practical factors exercise by contacting David Hamlette at 876-1743.  Please schedule the practical at least 24 hours in advance (you can schedule it before coming to Jlab).


Pregnancy and Medical Concerns

Q: I'm pregnant. What should I do regarding radiation work? Is there any information I can read regarding possible risks to the embryo/fetus? Are there any forms to fill out?

A: Contact Becky Mosbrucker x7236.  They will be able to advise you on how to proceed with your work and provide you with reading materials and references. 

You are encouraged to submit a Declaration of Pregnancy which will allow us to more closely monitor your radiation exposure and may result in some work restrictions.  If you formally declare your pregnancy, you will be subject to lower dose limits for the duration of your pregnancy.


Q: I previously filled out a "Declaration of Pregnancy” form and filed it with the Radiation Control Department, but I changed my mind. Can I "undeclare" my pregnancy?

A: Yes. You can withdraw your "declaration of pregnancy" by filling out a Withdrawal of Pregnancy Declaration form, and submitting it to Becky Mosbrucker.


Q: I had a nuclear medicine procedure involving radionuclides (e.g., Tc-99, I-129, I-131, Tl-201), what type of dose did I receive?

A: This website can give you a general idea of the radiation dose you may have received.  General disclaimer: Jefferson Lab does not control the referenced website, and the website should only be used as a ballpark estimate.


Q: I've had a nuclear medicine procedure (i.e., been injected with a radiopharmaceutical/radioisotope).  Can I still come to work?

A: It depends.  First of all, please follow your physician’s instructions.  In addition, you must inform the RadCon Dosimetry Office x7236 of your radiopharmaceutical status.  Before returning to work, stop by our office;  we will measure the dose rates created by the radionuclides in your body and impose appropriate work restrictions (see table for guidelines).

Measurement Distance

If reading is greater than:

Then impose work restriction:

On contact

0.05 mrem/h

Do not wear dosimeter

Do not work in RCAs

1 meter

0.05 mrem/h

Stay at least 1 m away from co-workers

1 meter

0.25 mrem/h

Do not report to work (stay home)


ARM/Accelerator Operator Related

Q: When does a Safety Checklist have to be initiated?

A: A Safety Checklist should be performed for CEBAF or the LERF if the accelerator in question has been shutdown in excess of 24 hours. The purpose of the checklist is to ensure no barriers to personnel safety have been compromised or left in an unsafe condition as a result of system maintenance.


Q: There’s an issue with the Beam Loss Ion Chambers, what do I do?

A: Call Dave Seidman at x7054 or Rick Gonzales at x7198.


Q: Where do I get blank survey sheets?

A: Copies of current survey maps can be found here.


Q: Can an ARM de-post a radiation area?

A: No.  ARMs shall not routinely post or de-post radiological areas.

Q: Can an ARM de-post a high radiation area?

A: No.  Since ARMs are not allowed to routinely post HRAs, they should not de-post them either.  Some exceptions may exist, contact David Hamlette (876-1743) for further details.


Q: Can an ARM conduct the beamline surveys necessary for hands-on beamline work in Hall B and the LERF during a "Rapid Access" entry?

A: Yes.  If a radiation area or hot spot is found, normal limitations apply.


Q: If the “Rapid Access” system beacon is on in Hall B or the LERF, can an ARM conduct the area survey?

A: Yes.



Q: I need Radiation Safety Analysis Document (RSAD), what information do I need to provide?

A: This information can be accessed on the RSAD information page.  In addition, information on a non-standard post target beam pipe must be submitted because this significantly alters the quantity of beam loss, and the subsequent neutron skyshine that dominates the site boundary radiation dose.


Q: I'm planning to do some work, but I'm not sure if I need a Radiation Work Permit (RWP).  Are there any guidelines?  How do I initiate the process?

A: Full guidelines are contained in sections 321 through 325 of the EH&S Manual RadCon Supplement (RadCon Manual).  An RWP is required for work:

·         in a 25 mrem/hr area

·         that will result in 25 mrem cumulative dose or more

·         on components with contact dose rates greater than 250 mrem/hr

·         on contaminated items

However, if process knowledge from a RadCon member indicates an RWP is not necessary (e.g., adjusting a valve for 30 seconds in a 30 mrem/hr area after consultation with a RadCon member), the requirement may be waved.

In the Accelerator Division, all planned work should have an ATLis entry.  If any of the aforementioned radiological conditions exist (or have the potential for existing), ensure RadCon is notified by including RadCon on the ATLis distribution.

Please fill out the appropriate information from the link here.  Please notify David Hamlette of this activity at least one week in advance of the planned work.  DO NOT EXPECT ANY RADCON SUPPORT IF THE SCOPE OF THE WORK IS NOT PROVIDED TO RADCON AT LEAST 8 HOURS IN ADVANCE.

If you have any questions, call David Hamlette at 876-1743.


Q: I am running an experiment in one of the experimental halls that utilizes He-3. Are there any special concerns, or anything I have to do?

A: He-3 is susceptible to inherent H-3 (tritium) contamination.  Tritium is readily dispersible in air and water, and is a radioisotope of concern on several of Jlab's environmental permits.  A He-3 gas release in an experimental hall may result in release of tritium directly to the environment through the air, or indirectly through condensation in dehumidification equipment and subsequent discharge through the sanitary sewer to HRSD.  In order to ensure that no environmental permit limits are exceeded for tritium, the EH&S Manual Radcon Supplement states in Table 2-2 that no more than 10 mCi of tritium contamination may be found in He-3 in any hall without consent from the RadCon Manager.  All He-3 purchases must be approved by the RadCon Department through the requisition process, as stated in section 432 of the EH&S Manual Radcon Supplement.  All He-3 bottles bought by users must either be sampled for tritium, or have the tritium quantity ascertained via pedigree by the RadCon Department.


Q: Where can I find RadCon related Tech Notes?

A: Technical Notes related to radiation control subjects, as well as equipment abandoned by the Accelerator, Administrative, and Physics Divisions (i.e., beam dumps, and experimental hall machine protection systems) are located in the Jlab document repository (Docushare)


Q: Where can I find Beam Dump/Beam Exit Pipe related Tech Notes?

A: These Tech Notes are located within the Jlab document repository (Docushare)


Q: How do I schedule a radiation survey to remove material from the beam enclosure?

A: RCTs perform RAM surveys for removing items from accelerator enclosures twice a day (morning and afternoon) provided the items are in a known staging area.  If you need substantial equipment surveyed, or at a particular time, notify the RCT Coordinator at 876-1743.  Note that if ARRANGEMENTS ARE NOT MADE WITH THE RCT COORDINATOR AT LEAST 24 HOURS IN ADVANCE, THE ITEMS IN QUESTION MAY NOT BE SURVEYED DUE TO SCHEDULING CONFLICTS.


Q: I need a radioactive source to perform an experiment. How to I purchase one? Are there available radioactive sources onsite for use?

A: RadCon has a number of radioisotopes in its possession that can be checked out.  To get a list of what is available, contact Adam Hartberger at x7463.  If the type and quantity of a radioisotope is not available, you can order one through the requisition system.  You will be queried as to whether the ordered item is a radioactive material.  When you answer 'yes', the requisition will be automatically transferred to the RadCon Department cue for approval.


Q: Where do I find information on boundary dose, radioactive air emissions, groundwater and other tracked parameters for Jefferson Lab?

A: The information is provided annually in Section 3 of the Jefferson Lab Site Environmental Report. Additionally, the annual "Environmental Radiation Resulting from the Experimental Program at JLAB" is located at M:Radcon/quarterly reports/etc.


Q: How does our collective dose compare with other DOE labs?

A: Our collective dose is fairly low compared to other labs.  A comparison of DOE labs’ annual collective dose is available on Radiation Exposure Monitoring System (REMS) website.  


Q: What is the basis for Jlab's radiation safety regulations?

A: The base documentation for all DOE Occupational Radiation Protection regulations is contained in 10 CFR 835. Jefferson Lab adheres to a number of other applicable environmental regulations and permits; however, 10 CFR 835 provides the "backbone" or framework on which the overall Jefferson Lab Radiation Protection Plan is based.


Q: I have a radiation safety concern that I would like to report.  What should I do?

A: You are encouraged to contact the RCD Manager directly at x7212 or via his cellphone at 876-5342. Your concern will be held strictly confidential.  Additionally, depending on the severity of the situation, a Radiation Safety Deviation Report (RSDR) or Notable Event Report (NER) may be filled out, with corresponding corrective actions to rectify the situation.


Q: Are there any means by which I can formally request an answer to a radiological condition I believe is unsatisfactory, or pose a recommendation?

A: The Jefferson Lab Radiation Review Panel (JRRP) exists to provide input and advice to the RCD Manager.  The JRRP is responsible for:

·         Reviewing the Jefferson Lab ALARA (As-Low-As- Reasonably- Achievable) Program activities and reports

·         Conducting critiques on deficiencies and proficiencies in radiological control activities

·         Reviewing plans for first-time or infrequent activities and changes of scope

·         Reviewing recommendations from the Radiation Control Department

·         Making recommendations to senior management and to those responsible for carrying out programs regarding the above                         reviews

The JRRP charter is contained in Chapter 2240 of the EH&S Manual, and minutes of meetings are available under the Jlab document repository (Docushare)