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Radiation Monitoring Policy Statement

The WVU Radiation Safety Committee (RSC) has adopted the policy that all radiation exposures are kept as low as reasonably achievable (ALARA).  West Virginia University and West Virginia University Hospitals are committed to compliance with the radiation protection limits specified by United States Nuclear Regulatory Commission (NRC) in 10 CFR 20 and by West Virginia Radiological Health Program in 64 CSR 23. These dose limits apply to radiation exposures above those received from background radiation and medical exposures. The regulations require that doses from external and internal sources must be monitored if an individual is likely to receive a dose in excess of 10% of the applicable dose limits. If both external and internal doses must be monitored, the dose resulting from each must be added together and the sum compared to the appropriate annual limit. 

Radiation Dosimeters


Genesis UltraTM Thermoluminescent Dosimeter (TLD Badge)

  • External exposure to radiation is monitored by wearing a dosimeter “badge”.
  • This radiation dosimeter is used for determining deep-dose equivalent radiation exposure to the torso and head from external sources of gamma radiation, x-ray, or beta radiation with maximum energy greater than 0.25 MeV and has a minimum reportable dose of 1 mrem.
  • Thus, the  dosimeter will not record the low energy beta radiation of H-3, C-14 or S-35, because these betas are too weak to penetrate the paper wrapping on the film. However, these betas are too weak to penetrate the outer layer of skin. 
  • The dosimeters we currently use are customized to include the department, user name, wear date, account number, participant number, and serial number.
  • The whole body dosimeter will be labeled with a WB and the collar dosimeter will be labeled with a CL, and a fetal dosimeter is a blue or white dosimeter and will be labeled with an FET or Fetus.


Ring Dosimeter

  • The Ultra RingTM is an extremity dosimeter (ring badge) and is worn on the finger and used to determine shallow dose equivalent from external sources of gamma, x-ray, and beta radiation to the fingers and hands.
  • The 0.25 MeV cutoff for beta radiation applies here also. The minimum reportable dose is 20 mrem.
  • Required when handling gamma or high energy emitting isotopes for medical use or if using more than 1 mCi of P-32, I-125, Cr-51, Na-22, Fe-59, Rb-86, Cl-36 for research purposes, or using an open beam x-ray diffraction unit.
  • Identification is permanently engraved by laser and cannot peel, smear, or wash off. The ring badge is safely encapsulated inside the tamper-resistant cover. The ring is customized to include wear date, account number, participant number, user name and serial number.
  • Designed with strong hard plastic construction and comes in sizes Small, Medium, Large. Smooth edges allow rings to easily slide and fit inside of disposable gloves.

Wearing The Dosimeters

A whole body dosimeter or ring monitor can be worn throughout the day if you wish, however, it shall be worn at all times when working with radiation sources. This includes waste areas for radionuclides and radioactive material.  A whole body dosimeter is used to monitor radiation exposure to the worker’s torso and head. Wear the ring dosimeter on the finger which will potentially receive the highest shallow-dose equivalent. (This may not be your ring finger.)  Wear the ring monitor with the marked side on the palm side of your hand toward the radiation source. The ring should be worn under gloves to prevent possible contamination when using radionuclides.  Do not put monitors inside your pockets or under your lapel and don’t take them home.  Find a safe place to store your dosimeter(s) when you are not using it and where it is not exposed to radiation. Never wear another individual’s dosimeter (no sharing); always wear your own.  Dosimeters are not water proof.  If they are washed and dried they must be replaced.

Wearing Single Dosimeter without Protective Lead Apron

Radiation workers with a single dosimeter who are Not wearing a lead apron should wear their dosimeter between the chest and waist.

Wearing Single Dosimeter with Protective Lead Apron

Radiation workers with a single whole body dosimeter who Are wearing a lead apron should wear their dosimeter at the collar of their lead apron or on the thyroid shield, outside of the lead.

Wearing Two Dosimeters with Protective Lead Apron “Double-badge”

Radiation workers are issued two dosimeters if there is potential for higher radiation doses, such as individuals who perform or assist in fluoroscopic guided procedures. One dosimeter (Collar dosimeter) should be worn at the collar of the apron or on the thyroid shield, outside the lead. This collar dosimeter will be marked by a CL on the front.  The second dosimeter should be worn at the chest or waist, underneath the lead apron. This whole body dosimeter will be marked by a WB on the front. Note: the whole body dosimeter worn underneath the lead apron must never be used as a standalone dosimetry option and must always be paired with the collar dosimeter outside the lead. This double-badge method takes into account the radiation attenuation provided by the lead apron as well as the radiation dose to the head. The dosimeters must be worn at their specified locations. Accidental exchange of wear location will skew the end calculation of effective dose.

Requesting Dosimeters

  • It is the responsibility of the Authorized Radiation User to ensure that all occupational workers using radiation under their authorization are provided the required radiation monitoring devices. To request a whole body, collar or ring dosimeter visit the Radiation Safety Department (RSD) web site https://www.hsc.wvu.edu/rsafety/forms/. Click on the Badge Application link under Lab/Personnel forms to be taken to the badge application form. This form must be completed before a dosimeter can be issued.
  • The present policy of the Radiation Safety Department is to issue radiation monitoring devices, after receiving the application to all occupational workers whose job assignments include working directly with radioactive material or radiation producing devices, or to those who are expected to receive a dose in excess of 10% of the applicable dose limits. A ring dosimeter is required when working with quantities of gamma or high energy beta emitting radioactive material of more than 1 mCi or when working with open beam analytical x-ray devices. However, if a person works only with H-3, C-14 or S-35 and is not exposed to any other source of radiation, then this person has no need of a dosimeter.  
  • When an occupational worker is using radioactive materials or radiation producing devices in two separate job assignments or units (e.g. Nuclear Medicine and PET Center) it may be necessary to issue the worker separate dosimeters to wear in each job location. Other individual monitoring devices may be required for monitoring exposures to the eyes or to airborne radioactive material. Contact the RSD for specialized radiation monitoring services.
  • Upon completing an application requesting a dosimeter, the employee will be asked if they had previously been monitored for radiation exposure at another facility. If they answer yes, that facility will be contacted requesting that individual’s radiation exposure history. In addition, the employee will be asked if they are currently being monitored for radiation exposure at another facility. If they answer yes, the other facility will be contacted requesting that individual’s radiation dose records for the current year. The dose that the individual may be allowed to receive in the current monitoring year will be reduced according to 10 CFR 20.1201(f). If the employee will be working at multiple institutions it is the employee’s responsibility to provide Radiation Safety Department with a Form 5 annually.
  • Temporary (spare) dosimeters can be obtained from the Radiation Safety Department upon request until the permanent device(s) are received from Mirion (normally 7-14 days). Individuals who have lost their assigned dosimeter should inform the Radiation Safety Department of the lost dosimeter, and they will be given a spare dosimeter to be worn during the rest of the wear period. Spare dosimeters may be requested to be worn by visitors to the facility, if necessary.
  • Each unit, lab or division is allocated one or more series codes based on their needs and a Coordinator is assigned to administer the distribution and collection of all dosimeters (whole body, collar, fetal, and rings) on either a quarterly or monthly basis, depending on circumstances.  Dosimeters should be used beginning on the wear date on the dosimeter or as close to that date as possible. 

Return Process

At the end of each wear period the dosimeters will need to be returned to the manufacturer for analysis.  Individuals must return whole body badges and the rings to the Unit Coordinator who will then forward the dosimeters to the Radiation Safety Department for processing.  It is important that you return all dosimeters whether used or non-used at the end of each wear period.  The dosimeters must be received by the Radiation Safety Department no later than 15 days after the end of the wear period. Late badges and non-returned badges are considered a regulatory non-compliance violation and may result in unfavorable disciplinary action.  Because evaluation of dose is an important part of the radiation protection program, it is important that users return dosimeters on time. Thorough efforts should be taken to recover any missing dosimeters. Delays in processing a dosimeter can result in the loss of stored information. You must return all the radiation monitors (whole body, collar, fetal, or rings), not only to comply with regulatory guidelines and commitments but in order for your unit to receive credit for the chips and filter components that are removed for recycling. The shipping containers that the Coordinators receive containing the monthly or quarterly radiation monitors are designed to be reused by the Coordinators for returning the dosimeters to the Radiation Safety Department. 


The Radiation Safety Department receives quarterly exposure reports from Mirion for Authorized Users and Occupational Workers which are promptly reviewed by the Radiation Safety Officer to ensure that radiation dose limits are within our established Occupational ALARA Program at WVU and WVUH.  Each series code Coordinator is sent a copy of these reports for posting and occupational radiation worker review.  Explanations and remarks regarding this report can be found on the reverse side of each report.  Note that there may be a several month delay from the time a badge is returned before the report is available. An individual who has questions regarding their exposure report should contact the Radiation Safety Department.  In addition to the monthly and/or quarterly exposure reports an annual radiation exposure report is prepared by Mirion and distributed by Radiation Safety. Records of individual monitoring results will be maintained in accordance with applicable regulations in 10 CFR 20 and in 64 CSR 23. For individuals with lost or missing dosimeters, an evaluation of the dose will be performed, documented, and added to the individual’s dose record. The individual’s recent dose history will be the basis for the dose evaluation. If that information is not available, an estimated dose we will calculated based off exposure data from other individuals performing similar job tasks.

Interpreting Radiation Exposure Results

Radiation workers will notice on their dosimetry reports the dates for which the radiation dose was received and radiation doses (in the unit of millirems) for the current monitoring period, quarter to date, year to date, and lifetime to date. The report will have columns for deep, eye, and shall. (shallow) radiation doses. A deep dose (DDE) is the measurement for dose at a tissue depth of 1 cm and applies to whole body exposure. An eye dose (LDE) is the measurement for dose at a tissue depth of 0.3 cm and applies to lens of eye exposure. A shallow dose (SDE) is the measurement of dose at a tissue depth of 0.007 cm and applies to shallow dose of the whole body.

Double-Badge Exposure Results

Radiation workers who wear two dosimeters, one at the collar outside the lead apron and one underneath the lead at the chest or waist, will notice that there is an EDE calculation value in addition to exposure results for each dosimeter. This EDE calculation is the effective dose equivalent and sums the two exposures representing an entire body overall risk. The calculation is 1.5 times the dose reported by the whole body dosimeter, plus 0.04 times the dose reported by the collar dosimeter.

Example:           Whole body dosimeter reading = 50 mrem

                        Collar dosimeter reading = 1500 mrem

                        EDE = (50 mrem * 1.5) + (1500 mrem * 0.04) = 135 mrem

ALARA Compliance

A personalized ALARA memo is generated by Mirion notifying the Radiation Safety Department if an  occupational worker’s exposure in that quarter exceeds the ALARA (As Low As Reasonably Achievable) Investigational Level. The memo indicates the exposure and level exceeded and is sent to the RSD to review.  According to our “ALARA Program”, the Investigational Level exposure notice is investigated by the RSO to determine the cause of the unusual exposure and may require additional action from the appropriate administrator.  The occupational worker is required to complete a questionnaire and return it to the RSO as part of the investigation. Receiving notification of a radiation exposure exceeding an Investigational Level does not necessarily mean the occupational worker is on pace to meet or exceed annual occupational dose limits. Investigational Levels serve as check points above which the results are considered sufficiently important to justify investigation. The annual radiation dose limits and WVU ALARA Investigation Levels per calendar quarter are listed in the tables below.

WVU ALARA Investigational Levels                                   

NRC Investigation Levels

Annual Radiation Dose Limits

NRC Occupational Dose Limits


Radiation Safety currently bills the unit, department, or lab using the assigned “Series Codes” quarterly for all radiation monitoring services provided by our dosimeter vendor (Mirion). This includes TLD rings, whole body badges, room monitors, postage & freight, administrative service fees, clips, non-returned monitor fees, unreturned ring badges, annual reports, and various other vendor provided services. Invoices are prepared by Radiation Safety Department and sent out quarterly requesting payment within 30 days in the form of check, credit card, internal transfer or transfer between bank account.

Fetal Radiation Dose Monitoring

A pregnant woman can decide whether she wants to formally declare her pregnancy to take advantage of lower dose limits for the embryo/fetus.  It is up to the pregnant radiation worker to decide whether or not she will formally declare her pregnancy to her supervisor in writing and/or the RSO.  If she chooses not to declare her pregnancy to the RSO, only the individual monitoring limits for an adult radiation worker will be in effect.  General consensus is to limit the radiation dose received by the pregnant woman and the embryo/fetus. Therefore, it is recommended that an occupational worker who utilizes radioactive materials and/or radiation producing devices in their job assignment should inform their supervisor in writing of their desire to declare their pregnancy.  All data of a private nature will be protected from unauthorized disclosure.  The supervisor should endorse that the declared pregnant woman contact Radiation Safety to obtain information on risks to the embryo/fetus from occupational radiation exposure and review methods that may be used to keep doses low.  A monthly fetal dosimeter will be assigned to the declared pregnant woman to monitor the embryo/fetal dose and is to be worn on the waist in addition to the individual monitoring device. If a lead apron is to be worn the fetal dosimeter must be worn underneath the lead apron. This change in monitoring, as well as the associated dose restrictions, remains in effect until it is withdrawn in writing from the woman or she verbally communicates with Radiation Safety stating that she is no longer pregnant.  The declaration can be withdrawn at any time.  No explanation is required.

For protection of the embryo/fetus of a declared pregnant woman, the dose to the fetus should remain less than 500 mrem (5 mSv) during the entire pregnancy.  Efforts must be made to avoid substantial variation above a uniform monthly exposure rate to a declared pregnant woman so as to satisfy the aforementioned limit. Thus the monthly exposure during pregnancy should be less than 50 mrems (0.5 mSv). The fetus is very sensitive to high doses of ionizing radiation, especially during months one thru three of gestation.  Each month an exposure report displaying the fetal dose for the month and accumulated fetal dose for the gestation period is received and reviewed by the RSO. Routine exposure reports for badges returned for processing have separate reporting as well.


Internal radiation exposure is rare, but it can occur if radioactive materials are inhaled, ingested, or absorbed. When this occurs, a bioassay may be necessary to measure the amount of radioactive materials in the body. The need for a bioassay will depend on the radionuclide used, circumstances under which it is used, the volatility of the substance, and amount of activity involved. Bioassays may involve collection of urine, blood, saliva, or nasal mucus. Thyroid bioassays are completed on individuals who have been exposed to volatile radioiodine using an external detector. Medical personnel should reference bioassay requirements in chapter 6 of the WVU Radiation Safety Manual for Medical Applications. Those utilizing radiation in a research setting should reference bioassay requirements in chapter 10 of the WVU Radiation Manual for Research Applications.