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Radioactive Waste

Radioactive Waste 

All radioactive waste on CSUSB is regulated by state and federal entities. Labeling, packaging, and disposal requirements for radioactive waste can be complex. Costs for radioactive waste disposal are not only based on the amount of waste but the hazard, and can be high, so waste collection and disposal operations must be conducted in a manner that will not unduly increase waste volume or hazard levels. Improperly packaging waste can increase volume when waste must be re-packaged and the original container, then, becomes waste. Collecting multiple radioactive sources in a single container can increase costs for disposal if any of the sources are in a higher hazard category.  

Special Precaution

If this is the first time you are managing radioactive waste on this campus or beginning use of a different isotope, please contact the Radiation Safety Officer (RSO) (909) 537-5179, before the commencement of work. Detailed planning of proper radioactive waste packaging, storage, and disposal procedures specific to your operations and in alignment with campus requirements are necessary. The best way to assure you meet all requirements is to check with the RSO before generating any radioactive wastes.  

Radioactive Waste Disposal Procedures 

All radioactive waste shall be organized in the following manner before submitting it for disposal:  

  1. Each isotope shall be kept in a separate container and identified by assigned Accession Number, specific isotope, activity, date, physical and chemical form, and Authorized User name. Dry waste must be separated from liquid waste. Liquid scintillation vials must be packaged separately from other liquid wastes. Both dry waste and liquid waste will be kept isolated in the Radiation Storage Room. Some aqueous liquid wastes may be sewer disposed; check with RSO. The waste can then be removed by a licensed radioactive disposal company.  

  2. Important: Surface contamination levels and radiation levels must be within acceptable limits to protect the health of personnel handling the waste (see Section III. A.1 and 2 of the Radiation Safety Program).  

  3. All containers must be sufficiently strong and durable to retain their contents even if they are dropped or otherwise abused.  

  4. All radioactive waste will be turned over to the RSO for storage and/or disposal as soon as practical after it is generated. Excessive amounts of waste must never be stored in a laboratory, faculty office, etc.  

Radioactive Waste Criteria 

There are only two types of wastes that must be considered:  

  1. Radioactive Waste with half-lives of less than 120 days   

This type of waste includes 32P (half-life = 14.3 days), 35S (half-life = 87.9 days), and 125I (half-life = 60.2 days). These isotopes will be stored in the Radioactive Materials Storage Room. Waste will be kept for a minimum of 10 half-lives before disposal as regular waste or as hazardous waste depending on the material. Following the retention period, waste will be surveyed before the disposal to confirm activity has decayed to a level indistinguishable from background.  

  1.  Radioactive Waste with half-lives of more than 120 days 

This type of waste includes 3H (half-life = 12.3 years) and 14C (half-life = 5,730 years). These isotopes will be separated as dry, liquid-aqueous, or liquid scintillation cocktail waste. This type of waste will be disposed of by a licensed contractor equipped to handle and dispose of radioactive materials. 

If you have questions or would like a radiation laboratory consultation, please submit an EH&S Service Request and the RSO will contact you.