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Cal State L.A.


Environmental Health and Safety

Exposure Monitoring for Individuals Working with Radioactive Material

The Nuclear Regulatory Commission, (NRC), along with various other federal and state agencies governs the use of radioactive materials, including exposure monitoring. CSULA is required to comply with all regulations set forth by the various state and federal agencies.

The guiding operational principle of radiation safety and the CSULA Radiation Safety office is to maintain exposures “as low as reasonably achievable?(ALARA). Exposure to ionizing radiation at this campus will likely occur from routine handling of radioactive material during planned research projects. Exposure may also occur during the process of responding to unexpected events such as spills or contamination in the laboratory.

The university exposure-monitoring program is managed using a risk-based approach. Only individuals using radioactive materials possessing sufficient energy to actually cause an exposure to be recorded receive badges to monitor exposure. Thus individuals working in labs using only S-35, P-33, H-3 and C-14 will not be monitored for exposure. Appropriate monitoring, including whole body dosimetry and finger dosimetry, has been instituted for users of P-32 with uses of stock solutions of 1mCi and above. Individuals using activities less than 1mCi of P-32 have the option to choose whether or not to be monitored. All x-ray diffraction workers, users of x-ray machines and users of other machines that produce ionizing radiation are required to have dosimetry (extremity and whole body). Users of multiple machines or high activity sealed sources are required to have redundant dosimetry for each unit so that an exposure may be more directly correlated to a specific unit, source or procedure.

Special considerations are taken for employees handling radioactive who become pregnant. However, an employee must declare their pregnancy in writing in order for the Radiation Safety Office to respond. If you believe you are pregnant, please complete the form attached below and submit to the Radiation Safety Office.

Declared Pregnant Worker

The chart below lists the occupational dose limits for adults and minors. These dose limits can be found in the NRC Code of Federal Regulations, Title 10 Part 20.

Occupational Exposure Limits

Whole Body 5 rem/year
Lens of Eye 15 rem/year
Extremity Dose (skin, hands, feet, etc) 50 rem/year
Individual Organ, other than lens of eye 50 rem/year
Embryo/Fetus of a “declared pregnant woman?/font> 0.5 rem during entire pregnancy
Minors (<18 years of age) working in areas where radiation is used 10% of annual limit allowed for adult
Members of the public, which include all workers or students with “non-occupational exposure 100 mrem/year

As a matter of practice, all “occupational exposures" at this university should not exceed 1/10th of the above limits. In the event that an employee received any exposure above this internal action limit, the Radiation Safety Office will conduct an investigation into the causes of the abnormal exposure results.

If you have questions or concerns about exposure monitoring, please contact the Radiation Safety Office at x6358.



5151 State University Drive . Los Angeles . CA 90032 . (323) 343-3000
2012 Trustees of the California State University

Last Update: 08/29/2012