Loyola University Chicago

Office of Research Services


Surveys will be performed by the RSO or his/her delegate per the schedule below. Laboratories and storage areas for radioactive materials in unsealed form will be surveyed for surface contamination and, if appropriate, external exposure rates. Laboratories where sealed sources are used will be surveyed for external exposure rates when appropriate.

In low background areas, except in those where H-3 is used, direct surface contamination surveys will be performed using portable survey equipment capable of detecting the radionuclides being used. For H-3, or where surface contamination is found to exceed the limits in the table for fixed contamination and in high background areas, a surface wipe will be made to determine if the activity is removable. Survey results are entered on the survey report form.

Survey frequencies will be based on the quantities of radioisotope used per experiment. Survey frequencies are shown below.

Activity (A) of Radionuclide Used per Experiment     Survey Frequency

A < 1 mCi


1 mCi < A < 50 mCi


50 mCi < A


In addition, users shall perform daily wipe test surveys, and where possible, instrument surveys:

  • During and at the end of labeling experiments involving millicurie quantities
  • During experiments involving millicurie quantities of P-32 or radioiodine

Storage areas shall be surveyed by the RSO or a delegate on a quarterly basis.

Contamination Action Levels:

Maximum acceptable contamination limits are listed in the table below. If these limits are exceeded, corrected measures will be taken. Action levels in unrestricted areas are those listed in 32 IAC 340. Appendix A Decontamination Guidelines and are reproduced below.

Alpha emitters

Removable     555 mBq per 100 cm2 \       / average
      15 pCi per 100 cm2    --     --over any
      33 dpm per 100 cm2   /      \ one surface
      1.67 Bq per 100 cm2  \  
      45 pCi per 100 cm2    --     maximum
      100 dpm per 100 cm2 /  


Total (fixed)     16.7 Bq per 100 cm2      \      / average
      450 pCi per 100 cm2      --     --over any
      1000 dpm per 100 cm2   /      \ one surface
      83.3 Bq per 100 cm2 =    \  
      2250 pCi per 100 cm2 =  --    maximum
      5000 dpm per 100 cm2    /  


Beta-Gamma Emitters:

Removable     3.7 Bq per 100 cm2  \      / average
(all b, γ emitters
except 3H) 
    15 pCi per 100 cm2  /      \ any one surface
      18.5 Bq per 100 cm2  \      maximum
      500 pCi per 100 cm2  /      


Removable (3H)     37 Bq per 100 cm2       \    / average
      1000 pCi per 100 cm2  /    \ any one surface
      185 Bq per 100 cm2   \      maximum
      5000 pCi per 100 m2  /      


Action levels in restricted areas shall be 10 times the levels in unrestricted areas.


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