RADIATION SAFETY REVIEW UIHC Environmental Services

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1 RADIATION SAFETY REVIEW UIHC Environmental Services Original material/information by Laurie Taylor, HPO, May 1999 Revised format by Mary Thompson, UIHC EVS, April 2006 For example, the transfer of heat from the burner on a stove to a pot of water causes the water to boil. It cannot be seen or felt. Precautions are taken around sources of ionizing radiation because of its ability to remove electrons from atoms. However, when proper precautions are taken, it can be used safely and is part of the backbone of modern medicine!

2 Other forms of radiation such as lasers, ultrasound, and microwaves are not forms of ionizing radiation. When an x-ray machine is turned on, radiation is present. When it is turned off, radiation is no longer being generated and no exposure occurs. Radioactive materials continuously emit radiation, but shielding is routinely used to minimize or eliminate exposure. Contaminated objects continue to emit radiation until they are cleaned or the radioactive material decays. Exposure to x-rays will not result in contamination.

3 Activity is the amount of radioactive material present. Some clinical machines at UIHC contain several hundred curies of radioactive material and are adequately shielded in several tons of lead. UIHC Housekeeping are not expected to receive more than 100 mrem per year at work. Radiation workers have an exposure limit of 5,000 mrem per year. This is the highest dose of occupational exposure that is NOT expected to cause adverse health effects even if received each year for 50 years! Background exposure occurs naturally in our water, food, soil and the air we breathe. It comes from our sun, outer space, and radioactive materials that are a natural part of our earth (e.g. rocks). Often, these are greater sources of exposure than those that occur in industry, medicine or research. Background radiation levels vary by location and are influenced by the type of rock or soil present, a location s elevation and other factors. Central USA = about mrem per year Some areas in Colorado = 700 or more mrem per year. Research has NOT linked an increase in the natural cancer rate or an increased risk of birth defects to low-level radiation exposure. 100,000 mrem or more is needed to produce radiation sickness! Smoking cigarettes (1.5 packs/day) = 1,300 mrem per year Watching TV = about 30 mrem per year.

4 Never clean up spills, hospital rooms, countertops, refrigerators, sinks or handle any other equipment or items in a restricted area or labeled with a Caution Radioactive Material warning label unless instructed by HPO staff. Do not remove bedclothes, dishes, trash, or other items from hospital rooms posted with radiation signs unless instructed by HPO staff. Always assume a radiation source is present if a patient s room is posted with a Caution Radioactive Materials warning sign, even if the patient is no longer occupying the room. Check at the Nurse s station BEFORE entering any patient room posted with a Caution Radioactive Materials sign and PRIOR TO performing any housekeeping duties in any of these type of patient s rooms. For certain patients, housekeeping duties cannot be performed until the room is cleared by HPO staff.

5 Report skin contamination and contaminated items to HPO (5-8501) without delay. Report emergencies, thefts, vandalism, unsecured areas or materials, or other unsafe conditions involving radioactive materials or radiationproducing machines to HPO (5-8501) without delay. Documents concerning licensed activities UI and UIHC employees may examine copies of any of the following documents located at the Health Protection Office, 122 Grand Avenue Court: o IDPH Regulations Standards for Protection Against Radiation IDPH regulations can be found at : o The University s radioactive Materials License o Monthly Dosimetry Reports o Iowa Department of Public Health Annual Inspection Reports REFERENCES Dowd: Practical Radiation Protection and Applied Radiobiology, Philadelphia, 1994, W.B. Saunders Company. Draganic, Draganic, and Adloff: Radiation and Radioactivity on Earth and Beyond, 1990, CRC Press, Inc. NCRP Report No. 105: Radiation Protection for Medical and Allied Health Personnel, 1989, NCRP. U.S. NRC: NUREG-0267, Revision 1. Principles and Practices for Keeping Occupational Radiation Exposures at Medical Institutions ALARA, Washington, D.C., 1982, Division of Facility Operations, Office of Regulatory Research. REVIEW TEST