Information Notice No. 84-43: Storage and Handling of Ophthalmic Beta Radiation Applicators
SSINS No.: 6835 IN 84-43 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C. 20555 June 7, 1984 Information Notice No. 84-43: STORAGE AND HANDLING OF OPHTHALMIC BETA RADIATION APPLICATORS Addressees: All medical licensees. Purpose: This Information Notice is provided as notification to licensees of recent findings where strontium-90 eye applicators were stored with radiation levels in excess of regulatory requirements and possibly unnecessarily exposed the public to radiation. Recipients are expected to review the information for applicability to their facilities and consider actions, if appropriate, to preclude similar problems occurring at their facilities. However, suggestions contained in this information notice do not constitute NRC requirements and no specific action is required. Description of Circumstances: During the past 2 years, Nuclear Regulatory Commission (NRC) inspectors have observed several beta applicators in closed storage containers with surface dose rates (from bremsstrahlung) in the range of 40-95 millirems/hour. Some of these boxes housing stronium-90 were stored so that radiation levels in unrestricted areas could exceed the requirements of 10 CFR 20.105(b). Measured dose rates were found to be greater than 0.6 millirem/hour at 18 inches from area boundaries. Therefore, if persons were continuously present in the area for 7 consecutive days, doses might exceed 100 millirems. The primary reason that the radiation levels are above 0.6 millirems/hour at 18 inches from boxed applicators is that the loose pieces of aluminum placed inside the boxes on the bottoms and sides by the manufacturer are often discarded by the recipients of the eye applicators. The aluminum pieces (called "donuts") provide the necessary shielding to prevent excessive bremsstrahlung radiation. Discussion: The following three alternative actions have previously been found to provide appropriate levels of protection: 1. Radiation surveys of the applicator in its closed storage container demonstrating the maximum radiation levels at 12 inches from each 8406050350 . IN 84-43 June 5, 1984 Page 2 of 2 of the container surfaces in accordance with the license terms and 10 CFR 20.201. Any reading exceeding 5 millirems/hour at 12 inches from the container surfaces, requires posting the room or area as required by 10 CFR 20.203(e). Storage and handling procedures must ensure that persons in unrestricted areas are not exposed to radiation levels in excess of the limits specified in 10 CFR 20.105(b). Some instances of high radiation levels have been the result of missing aluminum donuts from the boxes. 2. Shielding such as aluminum, wood, lucite, etc. which reduces the readings in unrestricted areas to less than 0.6 millirem/hour at 18 inches from the shielding. 3. Storage of the applicator and container in a secured area that is accessible only to the authorized applicator user and that limits the dose rate to the public to less than 0.6 millirems/hour at 18 inches from accessible surfaces of the storage area. No written response to this information notice is required. If you need additional information regarding this matter, please contact the Regional Administrator of the appropriate NRC regional office or this office. J. Nelson Grace, Director Division of Quality Assurance, Safeguards, and Inspection Programs Office of Inspection and Enforcement Technical Contact: Jack Metzger, IE (301) 492-4947 Attachment: List of Recently Issued IE Information Notices
Page Last Reviewed/Updated Tuesday, March 09, 2021
Page Last Reviewed/Updated Tuesday, March 09, 2021