Occupational Radiation Exposure Limits

Limits to and the Control of the Exposure to Ionizing Radiation

Limits to Exposure to Ionizing Radiation

1. In keeping with currently accepted practices and standards all unnecessary radiation exposures shall be considered undesirable. All radiation exposure shall be limited to As Low As Reasonably Achievable - (ALARA).

2. Occupationally exposed persons

No occupationally exposed person shall be permitted to receive a radiation dose in one calendar year in excess of those listed in this paragraph, except under the special conditions as specified in the State Rules and Regulations chapter 391-3-17. These exposure limits are (in Rems per calendar year): 

• Whole body, total effective dose equivalent: 5 (0.05 Sv)* 
• Hands and forearms; feet and ankles (Up to the elbow and /or knee): 50 (0.50 Sv)
• Skin of whole body (Shallow dose equivalent) : 50 (0.50 Sv)
• Eye dose equivalent: 15 (0.15 Sv) 
  * (1 Sv Sievert = 100 rem) 

3. Non-occupationally exposed persons (general public in restricted areas),

No non-occupationally exposed person (general public in restricted areas), shall be permitted to receive a radiation dose in one calendar year in excess of those listed in the paragraph except under specific conditions as stated in the State Rule and Regulations chapter 391-3-17. These exposure limits are (in Rems per calendar year): 

• Whole body, total effective dose equivalent: 0.1 (1.0 mSv)
• Furthermore the above dose (0.1) shall not be received at a rate of more than 2 mrem in any one hour. 

4. Minors

Minors (individuals under the age of 18) are permitted to enter or have access to areas authorized for the use, storage or disposal of radioactive materials only if they are doing so as part of an established, supervised course of study or as an employee of Georgia State University . All other minors are not permitted in these areas.

Those minors permitted in these areas but who will not work with radioisotopes must attend a radiation safety awareness course provided by the Radiation Safety Officer prior to their entering or having access to these areas. In no case shall a minor be permitted to receive a radiation dose in excess of 10 percent of the limits set forth in Paragraph 2 of this section.

Also, the dose to an embryo/fetus (for purposes of regulations are considered a minor) due to the occupational exposure of a declared pregnant woman shall not exceed 0.5 rem (5 mSv) during the entire pregnancy.

5. Occupational Exposure to Pregnant Women

Obviously, not all radiation workers may become pregnant. However, any radiation worker may have the opportunity to work with a radiation worker who is, or has the potential to, become pregnant. Principle Investigators may be required to supervise the activities of occupationally exposed pregnant women. Therefore, all radiation workers should be instructed in regard to the hazards of radiation exposure to unborn children. Also, the following policies apply:

• A pregnant radiation worker must make her own decision regarding whether or not to declare her pregnancy in accordance with NRC Regulatory Guide 8.13.
• The declaration of pregnancy must be submitted in writing to the Radiation Safety Officer. An example declaration form is provided in the appendix.
• Once pregnancy is declared in writing, the declaration will remain in effect for a period of 10 months from the date of submission, unless it is revoked in writing.
• The radiation exposure to the embryo/fetus of a declared pregnant woman shall not exceed 500 mrem during the entire term of the pregnancy.
• The radiation exposure to the embryo/fetus of a declared pregnant woman should not exceed an ALARA action level of 50 mrem per month. Any monthly exposure in excess of this value will be evaluated by the Radiation Safety Officer and the responsible Principle Investigator. When appropriate, corrective actions will be taken to prevent future monthly exposures from exceeding this ALARA action level.
• If a pregnant woman has already received > 450 mrem during the term of pregnancy by the time she declares, the limit for the remainder of the entire term of declared pregnancy shall be 50 mrem.
• If a declared pregnant woman has already received a radiation exposure of < 450 mrem by the time she declares, the monthly ALARA action level may be reduced by the RSO to a level that will ensure that the dose to the embryo/fetus will not exceed 500 mrem for the term of the pregnancy.

6. Occupational exposure to airborne radioactive materials

No occupationally exposed individual shall ingest or be exposed to airborne radioactive material in concentrations or amounts in excess of those specified in Appendix B, Table 1 of Title 10, CFR, Part 20. These concentration limits may not be altered by the use of respiratory protection or particle size determinations except as specifically authorized by these Federal and State Regulations. 

7. Human research subjects (Not Knowingly Pregnant)

All exposure of humans to ionizing radiations for the purpose of research should be kept to an absolute minimum. All research involving Human Subjects must have the prior approval of the Radiation Safety Officer, The Radiation Protection committee and the I nstitutional Review Board ( IRB ).

All human subjects involved in research projects, protocols or studies that involve the application of ionizing radiations shall:

• Have a prescription for the radiation dose from a medical physician licensed in Georgia.
• Be counseled by the physician, P.I or his/her designate about the effects of ionizing radiation related to their exposure and, if a female, the effects of the exposure on the developing fetus.
• Sign and date the standard consent form.

8. Human research subject (Pregnant)

It is the policy at Georgia State University that all research projects, protocols or studies that involve the application of ionizing radiations to a woman or any part of a woman who is knowingly pregnant as part of the research be presented to and unanimously approved by the Radiation Protection committee prior to approval by the IRB.

Research proposals submitted but not approved unanimously by the Radiation Protection committee will not be allowed at Georgia State University .

It is the opinion of the Radiation Protection committee that, due to the proven harmful effects of ionizing radiation on the human fetus, the proposing researcher must provide extraordinary justifications and detailed application procedures to the committee to seek approval for research involving the whole body or partial body application of any level of ionizing radiation to a woman who is knowingly pregnant.