This recommendation serves to minimize the amount of time required for decay and ultimately attempts to reduce disposal costs. The most commonly used isotopes are P32, S35, I125, H3, C14. Approximately 85 researchers at U.S.C. have permits to use radio-labeled isotopes which generate radiological waste. These include liquid radioactive wastes, solid radioactive wastes, and scintillation cocktail vials. Wastes are collected on a weekly basis and housed at the U.S.C. Health and Safety Programs Unit, until properly disposed.
Accumulated waste is disposed every six months.
U.S.C. contracts out with a private contractor for the disposal of solid radiological waste and scintillation vials. Liquid radiological waste is collected from lab experiment residuals. The waste is collected in plastic containers and carboys and stored in a Radiation Collection Room. According to Zurosky, all liquid wastes emptied have a measured activity of no more than 0.5 curies per milliliter. Solid waste refers to waste such as gloves, towels, and other items contaminated with radiation.