Stanford University


Medical and Biohazardous Waste

Biohazardous waste includes laboratory waste that contains or comes into contact with biohazardous material. Dispose of blood or components of blood or body fluids as biohazardous waste.

Santa Clara County regulates the disposal of medical and biohazardous waste. To determine the proper waste stream for your materials, see the Medical and Biohazardous Waste poster. If this poster is not available in your laboratory, you can print it or call (650) 725-3468 for a hard copy.

For more information on how to store waste –
For more information on common inspection findings –


Disinfectants vary in efficiency, contact times, and dilutions, depending on biological agents. For an overview of classes and uses, see this table comparing different disinfectants.

  • Chlorine (hypochlorite) compounds, such as bleach, are commonly used in labs because of accessibility and low cost. These inactivate vegetative bacteria, fungi, lipid and non-lipid viruses, Coxiella burnetii, and tuberculosis (TB).
  • Chlorine compounds have some effect in inactivating bacterial spores.
  • Recommended contact time: 10 minutes.
  • Recommended working dilution: 500 ppm (1:10 dilution of household bleach, 5% hypochlorite ion).
  • Recommended for: floors, spills (inactivating liquid specimens), bench tops, and contaminated clothing. Undiluted bleach and other disinfectants must not go down the drain.

Disinfection of prion and prion-like proteins must follow established WHO and CDC guidelines, found in section 3.8 Requirements for Research with Prions and Prion-Like Proteins in the Biosafety Manual.


For more information, contact the Biological Waste Department on the Main Campus at (650) 724-0794 or at the Medical Center/Hospital at (650) 723-6896.

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