- Determination of the Need for Personnel Monitoring
Personnel monitoring is required for certain individuals who directly handle radioactive material or radiation-producing devices. In general, the radiation levels within a given area are controlled in such a way as to limit exposures to others within those areas to insignificant levels. Before the initial monitoring devices can be ordered for a PH, an account number must be submitted to the RSO. The cost of routine personnel monitoring (including late, lost/unreturned, and damaged badges) will be the responsibility of the PH. The RSO may be contacted for current pricing information. The following criteria is used by the RSO to determine whether an individual requires monitoring for radiation exposure:
Radiation Type/Energy Nuclide(s) Activity/experiment Frequency/Type Beta-emitters < 300 keV 14C, 35S, 3H, 45Ca Any None Beta-emitters > 300 keV 32P, 36Cl, 131I < 1 mCi None > 1 mCi and < 20 mCi Quarterly body & ring > 20 mCi Monthly body & ring X/Gamma-emitters < 500 keV 125I, 51Cr, 111In,99mTc < 5 mCi None > 5 mCi and < 10 mCi Quarterly body & ring > 10 mCi Monthly body & ring X/Gamma-emitters > 500 keV 22Na, 64Cu, 60Co < 0.5 mCi None > 0.5 mCi and < 5 mCi Quarterly body & ring > 5 mCi Monthly body & ring
Depending on the radionuclide, the above limits may be lowered by a factor of 10 for minors and declared pregnant workers. Individuals who declare their pregnancy with the RSO will be given special instructions for personnel monitoring.
If the necessity for personnel monitoring is unclear, the RSO may require personnel monitoring on a trial basis for a finite period of time (e.g., three months). The result of this trial monitoring will be the basis for determining the need for continued personnel monitoring. The costs associated with the personnel monitoring during the trial period will be paid by the RSO.
- Procedures for Initiating Personnel Monitoring
All individuals who meet the radiation monitoring requirements must complete an A-5, Request for Personnel Monitoring Service, form. This form must be fully completed before a badge will be issued. A new A-5 form should be completed anytime an individual begins working for another PH that requires monitoring. There may be a month delay between the time the A-5 form is received by the RSO and the actual receipt of the individual's badge. (Personnel monitoring devices are provided by the vendor with the individual's name printed directly on the badge.) If it is necessary to initiate personnel monitoring immediately, a temporary badge may be obtained from the RSO and utilized until the permanent badge is received.
- Types of Personnel Monitoring
a. Whole body badge:
The whole body badge is used to determine an individuals whole body deep and skin dose. It should be worn on the torso of the body (e.g., on a belt loop or on a lab coat chest pocket).
b. Ring badge:
Individuals who are issued whole body badges and handle radioactive material are also required to wear a ring badge. These badges are available in small, medium, or large to accommodate different finger sizes. Medium rings will be ordered unless another specification is made. Ring badges should be worn on one of the fingers of the dominant hand (i.e., the hand one uses the most). For the most accurate measurement, the wide part of the ring, which contains the participant information, should be positioned toward the palm side of the hand. When using radioactive material, ring badges should be worn under protective gloves to prevent contamination.
- Frequency of Personnel Monitoring
Radiation monitoring devices may be assigned on a quarterly or monthly basis. Whole body badges are issued on a quarterly basis when the potential for significant individual exposure on a monthly basis is low and/or if personnel monitoring is required by a non-regulatory agency. When a ring badge is assigned in addition to a whole body badge, they should be exchanged at the same frequency.
- Exchanging Personnel Monitoring Devices
Generally, one individual within a group or department is designated as a contact for that group of badge recipients. A few days prior to the exchange date (end wear-date), the contact person will receive (via campus mail) and distribute the badges for his/her group. When the new badge is received, the used badge should be returned to the contact person who will mail it back to the RSO. It is very important to exchange badges promptly. Failure to return used badges delays the badge readout process and in some cases results in an erroneous readout of the badge. In addition, the RSO charges a fee for each badge that is not received within two weeks of the badge end wear-date. If an individual does not receive a new badge at the appropriate time, the current badge should be utilized and the contact person and/or the RSO notified.
- General Procedures for the Care and Use of Personnel Monitoring Devices
The following guidelines should be observed to achieve accurate data from radiation monitoring devices:
- Badges should only be utilized by the individual whose name appears on the badge. Remember that these devices are used for estimating radiation exposure to an individual and do not actually protect the individual wearing them.
- Badges should never be cut, torn, or opened. All badges should be returned to the RSO in the same condition which they were received.
- When not in use, personnel monitoring devices should be stored well away from sources of radiation exposure.
- All personnel monitoring devices are issued for estimation of occupational exposure received at this institution only. Badges should not be taken home or otherwise removed from the University premises; however, it is important to notify the RSO if you are occupationally exposed to radiation at another place of employment.
- Upon termination of employment, all badges and holders should be returned to the RSO. At that time an A-13, Employee Status Change, form should be completed and submitted to the RSO.
- The RSO should be contacted immediately if any of the following events occur:
- a badge is left near a radiation source
- a badge is contaminated with radioactive material
- a badge is exposed to excessive heat and/or humidity (e.g., placed in a washing machine or a dryer)
- the film packet is cut/torn in such a way as to allow light to enter
- the badge is lost
- Exposure Reports and Histories
The vendor-provided dosimetry report is initially received and reviewed by the RSO. There is usually a two to four week delay between the collection and reporting of individual exposures due to processing and mailing. However, the vendor will immediately notify the RSO by telephone of any high exposures. Once dosimetry reports are received from the vendor, the RSO investigates exposures as stipulated in the University's ALARA program. A copy of the dosimetry report is then forwarded to the contact person for each individual to review. Another report is retained by the RSO.
Individuals who have been issued personnel monitoring devices at other institutions are asked to provide the names and the addresses (including zip codes) of those institutions on the back of the A-5, Request for Personnel Monitoring Service, form. If an individual knows his/her exposure received at these institutions, it should be provided to the RSO.
An individual may request a copy of his/her exposure history at any time. After leaving the University this may be accomplished by sending a written memorandum to the RSO providing his/her name, social security number, department he/she worked in, and the dates of employment.
The necessity of bioassays, as well as the necessity of air monitoring, is determined by the RSO and/or the RRSC based upon the chemical form, the amount of the radioactive material being used, and the intended use. Bioassays may also be required if uptake of radioactive material is suspected (e.g., personal contamination). The following are two types of required bioassays:
- Thyroid Bioassays:
Thyroid bioassays will be performed by the RSO between 24 and 72 hours after each iodination procedure. All individuals must have a baseline bioassay conducted before their initial use with radioiodine. The RSO should be contacted to set up a convenient time to do so. The necessity and/or frequency of thyroid bioassays for other procedures will be at the discretion of the RSO.
- Urine Bioassays:
The RSO may require urine samples from individuals who handle quantities of radionuclides in excess of 20 mCi per experiment. This condition will be addressed in the PH's permit. Unless otherwise instructed in the permit, these samples should be taken 24 hours after radionuclide use and delivered to the RSO for analysis.
- Thyroid Bioassays: