Radiation Safety Office

Definitions and Examples

Aqueous Radioactive Waste: A radioactive liquid whose pH is in the range of 6 to 9 and which contains no hazardous or dangerous components.

Authorized user: A person (typically a Principal Investigator) trained and badged by the Radiation Safety Office who has received permission from the Radiation Safety Committee to use and possess radioactive materials and supervise the use of radioactive material by others.

Biohazardous wastes: Environmental Health and Safety considers the following materials to be biohazardous:

  • Recombinant DNA
  • Oncogenic viruses
  • Infectious agents
  • Blood and blood-contaminated materials
  • Animal carcasses and parts
  • Chemical carcinogens in tissue mediums
  • HEPA filters from biological safety cabinets and BL-III facility exhaust ducts

If questions arise regarding biohazards, contact Environmental Health and Safety http://www.ehs.wsu.edu/ . Telephone 335-3041.

Dry solid waste: Waste comprised of solid materials containing no liquids.

Long-lived Isotopes: Radioactive isotope whose half life is greater than 90 days (e.g. 45Ca, 22Na, 137Cs, 232U, etc.).

Mixed Waste: A radioactive liquid whose pH is outside the range of 6 to 9 or which contains substances considered to be hazardous and/or dangerous by the state of Washington. Environmental standards for the state of Washington are strict. Please consult with Environmental Health and safety to determine if the substances or concentrations other than radioactive material in your waste are hazardous. http://www.ehs.wsu.edu/ There are only three scintillation fluids currently approved by the State of Washington Department of Ecology as non-hazardous. Using one of these three will keep your scintillation waste from becoming a mixed waste.

Radiation worker (a.k.a. badged person): A person trained by the RSO and an individual authorized user who receives a badge for monitoring radiation exposure resulting from work with radioactive materials.

Sharps: Glass pipettes, broken glass, needles and any other sharp items .

Short-lived Isotopes: Radioactive isotope whose half life is less than or equal to 90 days (e.g. 32P, 33P, 51Cr, 125I, 35S, etc.).

Transuranic Isotopes: Radioactive isotope whose atomic number is greater than 92.

Dangerous Waste Label: Available through Central Stores.

Radioactive Waste Receipt: Available through Radiation Safety Office.

Horizontal Entry Sharps Container: Available through Central Stores.


Related Links


Radioactive Delivery Record
Radioactive Sanitary Sewer Disharge Record
Summary of Radionuclides Disposals to the Air



Radiation Safety Office, PO Box 641302, Washington State University, Pullman WA 99164-1302, 509-335-8916, Contact Us