The Radiation Safety Committee, appointed by the Chancellor, formulates radiation policies and procedures. Responsibility for carrying out these policies and procedures rests with the Radiation Safety Officer who directs the Radiation Safety Section of the Environment, Health and Safety Department.
The University of North Carolina at Chapel Hill has been authorized by the State of North Carolina Department of Health and Human Services, Radiation Protection Section, to use radiation sources in operations, education, research and development activities. The UNC-Chapel Hill Radiation Safety Committee may authorize individual faculty members, as Authorized Users, to use radiation sources after a review of the proposed use, adequacy of facilities, and experience of the applicant.
To obtain authorization to procure and use radiation sources, a prospective Authorized User must complete and submit applicable Schedules of the Laboratory Safety Plan. For help in completing the radioactive materials portion of the Laboratory Safety Plan, please reference “Characteristics of Commonly Used Radionuclides”.
The body may be irradiated in two general ways; externally from radioactive material or radiation sources, or internally from radioactive material deposited in the body. External doses can be the result of exposure to gamma, x-ray, or high-energy beta emitters. Low energy beta and alpha emitters lack the energy needed to penetrate the outer layer of skin and subsequently present less of an external hazard, and are of more concern when ingested.
When ordering radioactive materials, purchase requisitions are to be sent directly to EHS, 1120 Estes Drive Extension, CB# 1650, for approval and forwarding to the Purchasing Department. In most instances, requisitions are forwarded within two hours after receipt by EHS. Failure to forward requisitions directly to EHS will result in their return without processing.
The University is required to maintain accurate, timely records of the receipt, use, transfer and disposal of radiation sources in its possession. Authorized Users have this same responsibility for their sources. These records must be maintained by the Authorized User for at least three (3) years and be readily available for periodic review by EHS and/or regulatory personnel.
Prevention of the spread of contamination and excessive radiation exposure is the responsibility of the Authorized User. The Authorized User is also responsible for providing radiation detection equipment to monitor removable contamination and external radiation exposure levels as appropriate. Radiation detection devices, such as liquid scintillation counters, gamma counters, and portable survey instruments, must be available.
A radiation emergency may exist if unplanned exposure to radioactive material is possible due to loss, misplaced material or accident; or if same loss, misplaced material or accident may result in contamination of facilities or spread of contamination out of control. Since an emergency requires immediate action to reduce harm or damage, mCi quantities should be considered an emergency and uCi quantities should be considered an incident.
Personnel monitoring devices (whole body dosimeters, extremity dosimeters, pocket dosimeters, etc.) are provided by the EHS through the Radiation Safety Office to measure an individual's radiation exposure to gamma, energetic beta and x-ray sources. The standard monitoring device is issued as a clip-on badge or ring badge bearing the individual assignee's name, date of the monitoring period and a unique identification number.
It is important to dispose of radioactive waste in accordance with radiation protection regulations. This avoids exposure to personnel and contamination of the environment. It also avoids regulatory penalties and the possible loss of radioactive material use privileges. Radioactive wastes are not permitted to be disposed in the sanitary landfill and must not be placed in any container used for the collection of non-radioactive waste, no matter how temporary the use is intended.
Under the terms of the University's authorizations to use radiation sources, EHS is charged with maintaining portal-to- portal surveillance of all radiation sources on the campus. In order to facilitate this surveillance and to insure that a high awareness of the rules and regulations governing the safe use of radiation sources is maintained, it is required that certain records and reference materials be maintained.
Any shipment of radioactive materials from the University must be in full compliance with U.S. Department of Transportation, U.S. Nuclear Regulatory Commission and/or North Carolina requirements. These regulations are constantly changing. EHS maintains current copies, and the staff is trained and knowledgeable in their applications.
Experimental procedures involving radioactive and/or bio-hazardous materials frequently require the use of building vacuum systems or vacuum pumps. Such procedures can result in the accidental contamination of the vacuum system or laboratory pump with hazardous aerosols or fluids. The vacuum system or laboratory pump must be protected with a secondary reservoir and disposable filter assembly when this possibility for contamination exists.
Projects involving administration of radionuclides to animals require information on specific arrangements for housing the animals during the project. Information required includes: The kind and number of animals to be used in the study (# per experiment + total # of experiments). The radionuclide to be administered per animal and how administered. The ultimate fate of the animal and suspected excretion rate of the radionuclide.
X-Ray diffraction and spectrographic devices generate in-beam radiation dose rates of 30 to 7000 rads/sec. Severe tissue damage can be inflicted by very brief exposures to these high dose rates. Surgical treatment or amputation may be required when small body parts, such as fingers, receive greater than 1000 rads.
Bone densitometers will be surveyed by the Radiation Safety staff at each source loading to ensure that anticipated exposure rates are not exceeded. All individuals using the devices will be registered with EHS as Radiation Workers. A trial period of personnel radiation monitoring may be put into effect.
Nuclear gauge design incorporates operator safety as a prime consideration. However, as with any device containing radioactive materials, some general precautions must be observed.
This document describes the procedures for proper installation and maintenance of UNC-Chapel Hill Cogeneration Facility Nuclear Coal Fuel Control Gauges.