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In general, all occupationally exposed personnel whose radiation exposure may exceed 10 percent of the annual allowable dose shall participate in a monitoring program. External exposure is monitored with the use of dosimeters which can be worn on the torso or the extremities. Exposure from internally deposited radioactive materials is monitored by either in vivo or in vitro procedures. 7.1 EXPOSURE INVESTIGATIONS An investigation will be made of all annual exposures exceeding 10% of the allowable dose and the investigative results will be documented and presented for review at the next quarterly meeting of the Radiation Safety Committee. The purpose of such investigation is to maintain compliance with the ALARA concept. The investigation will be initiated by the Radiation Safety Officer and will either involve a requested response to a written questionnaire or require discussion with the individual involved and the appropriate supervisor. In the case of well defined jobs that involve significant exposures to ionizing radiation; e.g., fluoroscopic use in a cardiac catheterization facility, investigations may not be made until 30% of the annual limit is reached. If the total dose exceeds 80% of the annual limit, the issue will be reviewed immediately by the Executive Committee. This committee may recommend to the appropriate administrative officer that the person receiving this level of dose be suspended from all further work with radioactive sources or radiation producing machines. It may also recommend more stringent actions depending on the magnitude of the exposure. The Committee shall also ensure that proper notification is made to the individuals and to the regulatory agencies. 7.2 DOSIMETERS For external radiation fields, exposure determinations are made by the use of personnel monitoring devices worn for varying monitoring periods up to but no longer than a calendar quarter. These may be whole body or ring dosimeters (OSL, TLD, film, track etch, or self-reading), in any varying combinations. Application for personnel monitoring dosimeters are made in writing on the approved form. Criteria for the type of dosimeter assignment and wear period are determined by the Radiation Safety Office. If dosimeters are assigned to an individual then he/she is required to wear the devices. The Radiation Safety Office will distribute and receive dosimeters, keep records of exposures, and forward the exposure data to persons or regulatory agencies upon request and as required. In cases involving non-homogeneous radiation fields, multiple body dosimeters or multiple ring dosimeters may be required. An additional dosimeter may be issued in the case of an individual who declares a pregnancy, to better estimate fetal dose. 7.3 MEDICAL EXAMINATIONS
No mandated medical examinations are required prior to or while working with ionizing radiation sources 7.3.2 Other If dosimeter readings indicate or if a
radiation worker thinks that a significant radiation exposure has occurred
the Radiation Safety will investigate and the Committee Physician will be
consulted. If a medical examination is warranted the individuals involved
will be provided with the results of their examination.
7.4
Urine and/or fecal analyses shall be performed on persons engaged in procedures involving quantities of radioactive material that may pose a significant risk. The radionuclides and activities for which this requirement is made will be specified by the Radiation Safety Officer. All required bioassays will be performed within time limits specified by Radiation Safety Office policy. The need for bioassays may be based upon the quantity of radioactive material used on single occasion or be based on cumulative use. 7.4.2 IN-VIVO MEASUREMENTS Persons engaged in frequent use of non-sealed gamma-emitting isotopes may be required to undergo whole body or specific organ in-vivo measurements at intervals specified by the Radiation Safety Officer. Persons using or handling radioiodine in quantities exceeding those in Table I, of NRC Regulatory Guide 8.20 are required to have a thyroid uptake determination. Thyroid uptake measurements may also be required when lower radioiodine activities are used or processed, depending on the form or compound, degree of airborne radioactivity control, frequency of use, nature of the research or clinical use, and other such variables. Current applicable regulatory guides are used for evaluating specific situations. In case of suspected internal contamination, the Radiation Safety Officer may require the performance of emergency whole body counting. 7.4.3 RESULTS OF BIOASSAYS The results of bioassay measurements will be kept in the dosimetry files in the Radiation Safety Office and upon request will be provided to the individual on whom the measurements are performed. Urine and /or fecal analyses shall be
performed on persons engaged in procedures involving significant potential
risk of inhalation and/or ingestion of radioactive material. The isotopes
and quantities for which this requirement is made will be specified by the
Radiation Safety Officer. All required bioassays will be performed within
three days following a single operation and at appropriate intervals for
continuing operations.
7.5 Refer to the "Pregnant Radiation
Worker Policy" in the Radiation Safety Training Manual.
7.6 Personnel should wear their University assigned personnel monitoring devices for any University related work exposure potential, even if it exists at locations other than the University proper. All non-University related exposures received by University employed radiation workers must be reported to the Radiation Safety Office at least quarterly when a non-University assigned dosimeter is worn. Should a situation exist wherein radiation exposure from work is not University related and a personnel monitoring dosimeter is not assigned, the Radiation Safety Office should be notified so that arrangements can be made to assess the exposure. |
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Radiation Safety Office Webmaster Revised February 9, 2001 |
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