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Frequently Asked Questions

ARMS/Accelerator Operators Related
Medical Concerns

ARMS/ Accelerator Operators Related

Q: When does a safety checklist have to be initiated?
A: A Safety checklist should be performed for CEBAF or the FEL if the accelerator in question has been shutdown in excess of 24 hours. The purpose of the conduct of this checklist is to ensure that no barriers to personnel safety have been compromised, or left in an unsafe condition as a result of system maintenance.

Q: The Beam Loss Ion Chambers have a problem. What do I do?
A: Call the person responsible for troubleshooting the "new" system, either Dave Seidman at 7054 or Rick Gonzales at 7198.

Q: Where do I get more survey sheets for performing surveys in the Halls, CEBAF or FEL?
A: Copies of current survey maps are kept on the RadCon webpage on the ARMS Information webpage.

Q: I'm an FEL ARM, what can I do concerning posting or de-posting of the FEL?
A: See the FEL Quick Access (QAS) conditions

Q: Can an ARM de-post a radiation area?
A: Yes. Assuming you can conduct a survey thorough enough to verify the absence of the condition. But it may be more efficient in many cases to leave it posted if you have reason to believe the condition will reappear shortly.

Q: Can an ARM de-post high radiation areas?
A: No. This is mainly a matter of consistency. Since ARMs are not allowed to routinely post HRAs, they should not de-post them either.

Q: Can an ARM conduct the beamline surveys necessary in Hall B and FEL in the event hands-on beamline work is to be conducted during a controlled access (during a "Rapid Access" entry)?
A: Yes. There is no reason an ARM can't assess these work areas. The same limitations as normal apply - if a radiation area or hot spot is found, the same triggers apply.

Q: Can an ARM conduct the area survey needed if the Rapid Access system beacon is on in hall B or FEL?
A: Yes.


Q: Do I need a dosimeter to enter a controlled area?
A: You do NOT need a dosimeter to enter a Controlled Area. You only need GERT training or a GERT trained escort to enter. A Controlled Area basically means an area within which you are likely to find a Radiologically Controlled Area (RCA) such as a Radiation Area or High Radiation Area, which would require a dosimeter. Thusly you need to know what those postings mean.

Q: Why do I have to keep my dosimeter at work? We could take dosimeters home at the other lab I worked at.
A: Although it is appealing to follow the mistakes of less safety conscious labs, the DOE RadCon Manual forbade DOE Labs established after 1992 from establishing a dosimetry program that allowed use of dosimeters off DOE premises. The reason for this is twofold. One, if a dosimeter is kept at home, the background level at your home may be slightly different than that at Jlab. Because there is no control badge at your home to subtract that background (as opposed to Jlab where control dosimeters are located in each badge rack), your dosimeter reading with Jlab subtracted background may be false. Two, 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 very rough estimates of actual dose received.

Q: I need Radiation Safety Analysis Document (RSAD), what information do I need to provide?
A: This information is found in the RSAD information page In addition to that information, information on NON-STANDARD POST TARGET BEAM PIPE MUST BE SUBMITTED as this significantly alters the quantity of beam loss, and subsequent neutron skyshine which dominates the site boundary radiation dose.

Q: I'm planning to do some work, but I'm not sure if it needs a Radiation Work Permit. Are there any guidelines? How do I initiate the process?
A: The full guidelines are contained in sections 321 through 325 of the EH&S Manual Radcon Supplement (RadCon Manual). An RWP is required for performing work in a 25 mrem/hr area, for work that will result in 25 mrem cumulative dose or more, working with material greater than 250 mrem/hr on contact, contaminated items, unless 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.) In the Accelerator Division, all work to be performed should have an ATLis entry completed. If any of the aforementioned radiological conditions may exist (or have the potential for existing, you should ensure RadCon is notified by including RadCon on the distribution. If you have any questions, call David Hamlette at 876-1743 or Vashek Vylet at 218-2733. Please fill out the appropriate information and forward it to David Hamlette at at least one week in advance of the planned work. DO NOT EXPECT ANY RADCON SUPPORT IF SCOPE OF THE WORK IS NOT PROVIDED TO RADCON AT LEAST 8 HOURS IN ADVANCE.

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, by nature of its production, is susceptible to inherent H-3 (tritium) contamination. Tritium is readily dispersible throughout air and water, and is also a closely tracked radioisotope of concern on several of JLAB's environmental permits. Because a He-3 gas release in an experimental hall may result in release of tritium, this tritium may be released directly to the environment through the air, or indirectly through condensation in the dehumidification equipment, and subsequent discharge through sanitary sewage disposal 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 in He-3 in any Hall without the consent of 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 brought by users must either be sampled for tritium, or have the tritium quantity ascertained via determination of the pedigree by the RadCon Department.

Q: Where are the RadCon related Tech Notes?
A: Technical Notes related to Radiation Control subjects, as well as equipment abandoned by Accelerator, Administrative and Physics Divisions (i.e., Beam Dumps, and Experimental Hall Machine Protection Systems) are located in the RadCon Technical note section.

Q: Where are the Beam Dump/Beam Exit Pipe related Tech Notes?
A: These Tech Notes are located within the Radiation Control Department webpage in the RadCon Technical note section.

Q: Where do I get information on my lifetime dose?
A: Dose records for all individuals issued dosimetry are available at the RCD Trailer (52B). Call Becky Mosbrucker at 269-7236 or email at for specific requests for dose history. Lifetime dose history from previous employers may be on hand, depending on the level of cooperation of individual previous employers in transmitting previous dose history.

Q: How do I get to schedule a radiation survey to remove material from the tunnel enclosure?
A: RCTs will 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: The RCD has a number of radioisotopes in it possession that can be checked out. To get a list of what is available, contact Adam Hartberger at 269-7463 or email him at If the type and quantity of 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 annual information is contained in the 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, especially considering the average annual background dose is on the order of 280-300 mrem.. Comparison of DOE Lab annual collective dose is available on Radiation Exposure Monitoring (REMS) homepage.

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 from 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 Radiation Control Manager directly at 269-7551 or his cellphone at 218-2733. 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: Is 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 Radiation Control Manager. The charter is contained in Chapter 2240 of the EH&S Manual. 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 conducting the actual programs regarding the above reviews.

Minutes of meetings are available at minutes of meetings.

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 at the RCD at 269-7236 or email at You will fill out a Declaration of Pregnancy Form, and give you some guidance concerning radiation risks to the embryo/fetus. You will have the option of having your radiation worker qualifications temporarily suspended, having your dosimeter read monthly, or wearing 2 dosimeters as delineated in the Fetal Monitoring Selection Form If you have further concerns, you can talk to the RCD Head at 269-7551.

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" a 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 at 269-7236.

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 nuclear medicine 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. Also, this NRC website has additional information on estimating radiation doses.

Q: I've had a nuclear medicine procedure (i.e., been injected with a radiopharmeceutical/radioisotope). Can I still come to work?
A: Yes, by all means, you are allowed to come to work (unless specifically instructed otherwise by a physician). You are not required to divulge any information of your procedure to anyone at Jefferson Lab. That being said, in order to keep an accurate record of occupational dose for you and your co-workers, the RCD requests that you provide information to the RCG of the radioisotope, quantity, and the day of the injection. This information can be provided by filling out and submitting the Declaration of Radiopharmaceutical Patient Form and returning the form to Becky Mosbrucker (269-7236) This information will remain strictly confidential. Additionally, (if at all possible), you should refrain from performing work in RCAs, and refrain from wearing your dosimeter until the radioisotope has effectively been cleared from your system. (The Radiation Control Manager can help you determine that assessment.)

The reason for the interest in this information is that the annual collective dose for all of Jefferson Lab is on the order of 1000 mrem, and a person who wears a dosimeter soon after a nuclear medicine procedure can (depending on the radioisotope and quantity, and wear the dosimeter is placed relative to the organ of interest) easily exceed a dose of 50 mrem. Such a dosimeter reading would and has triggered a dose investigation in order to ascertain how that dose could occur through work conditions.


Q: I lost my dosimeter. What do I do?
A: Contact Becky Mosbrucker at 269-7236 or email at in order to complete an Investigation Report and receive a temporary dosimeter.  NOTE: If your original dosimeter is found, please return it to Becky in Trailer 52B. Information will need to be collected from you to ensure that your radiation dose records accurately reflect the radiation dose that was received.

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 269-7236 or email

Q: I want to have my dosimeter in a different rack. What do I do?
A: Contact Becky Mosbrucker at 269-7236 or email at  She will initiate the transfer of your badge storage location.

Q: Where is the proper placement of my dosimeter?
A: Generally speaking, attached to an article of clothing on the "whole body" (on the torso to the elbows and knees). The key is that the dosimeter is firmly attached (and not dangling from a CANS badge lanyard.) Most recommended: in the chest region.

Q: Why can't I attach a dosimeter to my CANS badge lanyard? That way, when I take it home, I don't forget it.
A: The nature of the dosimeter as an albedo neutron dosimeter necessitates the use of the human body as an integral part of the dosimeter. Wearing the dosimeter "away" from the body causes the dosimeter to not function as intended for neutron measurement, and give false low readings. Dosimeters are not to be taken home, and MUST be stored in the storage racks. See Section 512.5 of the EH&S Manual RadCon Supplement.


Q: I just completed the GERT and/or Radiation Worker I test, when will I have access onsite? When will JLIST be updated?
A: JLIST is updated periodically (twice a day). You may not have unescorted access until JLIST is updated.

Q: Although I am 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.

Q: Can I take a written test for Radiation Worker I training?
A: Yes, we have written tests for those who prefer that method. Please call ext. 6021 to schedule a time to take a written test. As a reminder, you are required to view the on-line study information or read the on-line study guide before you may take the RWI test.  You can also take initial Radiation Worker training, which is offered in a classroom style, every quarter. A schedule can be located at the training office website located at:  If you have any questions, please contact Maya Keller at or call her at ext. 6021.

Q: What are the prerequisites to Radiation Worker II testing/class?
A: The prerequisites are successful completion of Radiation Worker I training, and approval from your supervisor. The study guide which you need to review before taking the RWII test is located at: RWII.pdf.  Or you may view the on-line study information at:

Q: Can I take the Radiation Worker II test without attending a class?
A: No, because the radiation worker II class is designed for teaching people how to work in potentially contaminated areas and/or with potentially contaminated items, a portion of the class is dedicated on proper techniques to use for dressing in and out of anti-contamination clothing. This information cannot be adequately conveyed through a written test.

Q: Where can I sign up for the RadiationWorker II class?
A: You can call 6021 or send an e-mail to When there is a group of at least 5 individuals, a class will be scheduled. Classes usually occur twice a year.

Q: When is the next Radworker I class? When is the next Radworker II class?
A: You must study the on-line study guide at Online Radiation Worker l before taking either test. If classroom instruction is desired, the upcoming schedule is listed on the The Radiation Worker II class must be taken "live".  You may contact Maya Keller at or call her at ext. 6021 to find out when the next RWII class is available.

Q: Is there a shorter radworker refresher class online?
A: An online version of Radiation Worker I is available. Note that you can take the RWI test at three different locations. You may come to the RadCon Trailer, 52B, JLAB Registration/International Services in Support Service Center Bldg. 28, or User Liaison Office in Cebaf Center Bldg. 12.

Q: What are the Radiation Worker training requirements for Users?
A:  Radiation Worker training requirements are listed on the User Liaison page. The Physics Division management has decided that Radiation Worker I training is required to access the accelerator site. If you believe you have no reason to access Radiologically Controlled Areas (e.g., you will only be accessing the "Counting House"), you may only need General Employee Radiation Training (GERT) which may be taken online at: Note that this training requires no proctored exam or practical factors. If this seems to be a more palatable option for your situation, please contact your sponsor.

Q: I'm a user preparing to come onsite. How long will it take to get my Radiation Worker I qualification?
A: You can prepare for the test by watching the Computer Based Training. You must then either take a proctored computer exam either at the RadCon Trailer, 52b, JLAB Registration/International Services Office in Support Service Center Bldg. 28, or User Liaison Office in Cebaf Center Bldg. 12. You must then take a practical factors exam after the computer test. You must schedule this exam at least 24 hours in advance.  It is possible to complete your RadWorker I qualifications in one day provided that you schedule your practical factors 24 hours in advance by calling (757)269-6021 or email  Also, if you need dosimetry, our on-line dosimetry request system can be accessed by using the following link:  If you need help with this system, please contact Becky Mosbrucker at or 757-269-7236.