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Radioisotope Source Possession and Use Requirements
Purchase, Receipt, and Transfer of Radioisotopes
Personnel Radiation Monitoring
Management of Radioisotope Laboratory and Use Area
Radioactive Waste Disposal Procedure
Radioactive Waste Disposal Chart
Mopping or Waxing of Radioisotope Use Areas
Radiation Emergencies
Radiation Safety Training
Policy on Declared Pregnant Radiation Workers
Policy on Eating and Drinking in the Laboratory
Radiation Protection Forms

X-Ray Safety
UMD-Radiation Protection Advisory Committee (RPAC)
Download this Manual in Printable (PDF) Format
Policy For Termination of Laboratory use of Hazardous Materials
10 CFR, Part 20: Protection Against Radiation
U.S. Nuclear Regulatory Commission (NRC)
Haz. Waste Mgt

Management of
Radioisotope Laboratory
and Use Area

I.   Laboratory and Radioactive Materials Use Areas Security:

Radioisotope sources and radioactive wastes must be stored in a secure area.  Therefore, it is required that radioactive material laboratory and use areas' doors must be closed all the time, and locked when no one is in the laboratory. Failure to do so constitutes a violation of the University's NRC License, and may result in a hold on radioactive materials purchases and possible permit close out.

II.   Shielding of Radioactive Sources:

Appropriate shielding must be provided so that radiation exposure rate from radioisotope sources is less than 2.5 mR/hour in any controlled area and less than 0.25 mR/hour in any uncontrolled area. Radiation exposure rates must be maintained as low as is reasonably achievable within these limits. 3-sided Lucite shields are available for P-32 short half-life solid waste containers from RPD. To order a Lucite shield for your lab, or for more information on available shielding materials and techniques, contact the Radiation Protection division at 612-625-1682.

III.   Radioisotope Laboratory/Storage Areas Posting:

All areas where radioactive materials are stored or used including refrigerators, freezers, hoods etc, must be labeled with a Radioactive Materials Caution Label (see picture to the side), to inform others of radiation hazard within the laboratory.  To request a "Caution Label" for your laboratory or equipment, contact our office at 7273, or by email at

Click image to view a larger size version

IV.   Record Keeping and Inventory:

An inventory of all radioactive materials under the use permit must be submitted to the RPD at the end of each calendar quarter. This inventory must include the total, decay corrected activity of each radioisotope in stock form as of the end of the quarter, plus the total decay corrected activity of each radioisotope in waste form as of the end of the quarter

  1. In order to maintain accurate radioisotope inventory records, All users of radioactive materials are required to keep on file radioactive waste inventory records, quarterly report records and employee training records.
    The RPD staff and the NRC audit these records annually and during inspection of the University NRC license.

  2. Use the Radioactive Waste Inventory Form to generate and maintain an accurate waste inventory. The use of this form will aid in tracking small amounts of radioactive stock material from the vial to ultimate disposal in a waste container. Once full, form should be used to determine total activity of each radioisotope in any individual waste container.

  3. Use the quarterly report form to generate accurate quarterly reports and records.

  4. Use the employee training form to maintain accurate employee training records.

V.   Laboratory and Use Area Surveys:

Contamination survey results, and in some cases exposure rate survey results, must be submitted with the Quarterly Report. All radioisotope use areas for which the permit holder is responsible must be accounted for on the Quarterly Report. A diagram of your areas, showing where smears were taken, must also be included with the survey results. Identify the area by using both the building name and room number(s).

A. Frequency of Surveys

  1. All active, radioisotope areas that are classified as "Low Risk", must have contamination surveys completed each month, and the results submitted with the Quarterly Report. Refer to your copy of the radioisotope use permit for the risk classification of your areas.
  2. All restricted areas where there was no handling of radioactive materials during the entire calendar quarter must have one survey completed during that quarter. This survey should be taken in the vicinity of any stored radioisotopes (e.g., refrigerator, freezer, cold room shelf, etc.), or radioactive waste containers.

B. Survey Information Requirements
  1. Surface contamination smear surveys are required for all restricted radioisotope areas. The surveys should be conducted using dry filter paper and analyzed with the appropriate counting instrument (liquid scintillation or auto-gamma counter). All results must be reported in disintegrations per minute (DPM).
  2. Record on the survey form which radioisotopes were used in the area.
  3. Record what counting efficiency was used in determining DPM.
  4. Record the make and model of the counting instrument.
  5. Number the smears and indicate on the survey map where these smears were taken.
  6. Describe their locations in the SMEAR SURVEY DATA column. Locations should include those where radioactive materials are stored, handled, and/or discarded. For example (work station bench top or fume hood working surface floor in front of work station, refrigerator/freezer shelves and handles, floor in front of refrigerator/freezer etc.)
  7. Record the DPM per 100 square centimeters for each smear. (DPM = [smear CPM - background CPM]/[fractional counting efficiency].
For more information on smear surveys consult the Quarterly Report Instructions
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