Biological Waste

The following biohazardous waste disposal guidelines are designed to protect the public, the environment, laboratory and custodial personnel, waste haulers, and landfill/incinerator operators at each stage of the waste handling process. Generators of biohazardous waste must ensure that the labeling, packaging, and intermediate disposal of waste conforms to these guidelines. Use the definitions below to facilitate your understanding of appropriate decontamination and disposal guidelines.

  • Decontamination- Refers to the process of removing disease-causing microorganisms and agents, rendering an object safe for general handling.
  • Disinfection- Refers to a process that kills or destroys most disease-causing microorganisms, except spores.
  • Sterilization- Refers to process that destroys all forms of microbial life, including spores, viruses, and fungi

Infectious Waste needing Decontamination:

Microbiological laboratory wastes such as cultures derived from clinical specimens and pathogenic microorganisms.

  • Lab equipment that may have come in contact with clinical specimens, pathogenic microorganisms, or cultures derived from them.
  • Tissues, large quantities of blood and/or bodily fluids from humans.
  • Tissues, large quantities of blood and/or bodily fluids from infectious animals.

Waste NOT needing Decontamination:

The following are not included as infectious waste but still need to be handled properly. Place these items into a container or plastic bag prior to disposal. Segregate these items from infectious waste.

  • Items soiled or spotted, but not saturated, with human blood or bodily fluid (spotted gloves)
  • Containers, packages, waste glass, lab equipment, and other materials that have had no contact with blood, body fluids, clinical cultures, or infectious agents.
  • Noninfectious animal waste (bedding, tissue, blood, and body fluids) or cultures from an animal that is not known to be carrying an infectious agent that can be transmitted to humans.

Packaging of Waste

Laboratory materials used in experiments with potentially infectious microorganisms, such as discarded cultures, tissues, media, plastics, sharps, glassware, instruments, and laboratory coats must be decontaminated before disposal or washing for reuse. Collect contaminated materials in leak-proof containers labeled with the universal biohazard symbol. Autoclavable biohazard bags are recommended. All infectious waste must be brought to the EHS Lab in Cushwa Hall #2205, when the container becomes 3/4 full, or a maximum weight of 30 pounds. 

Uncontaminated sharps and other noninfectious items that may cause injury require special disposal even if they do not need to be decontaminated. Sharps need to be collected in rigid, puncture-resistant containers to prevent wounding of workers, custodial personnel, and waste handlers. If a package is likely to be punctured from sharp-edged contents, double bagging or boxing is needed.

Methods of Decontamination

Choosing the right method to eliminate or inactivate a biohazard is not always simple. The choice depends largely on the treatment equipment available, the target agent, and the presence of interfering substances (e.g. media, high organic content, tissues) that may protect the organism from decontamination or mitigate the effects of the decontamination equipment.

  • Autoclave/Steam Sterilization:

    There are two main autoclaves located in the EHS department that are used for all infectious waste before the infectious waste transporter removes the waste from campus. They are operational during normal work days and process approximately 300 pounds of infectious waste per month. The operation and maintenance of the autoclave is the responsibility of the EHS department and is in accordance with manufacturer recommendations.

  • Chemical Disinfection:

    Where autoclaving is not appropriate, an accepted alternative is to treat material with a chemical disinfectant. The disinfectant should be freshly prepared at a concentration known to be effective against the agent in use. The disinfectant choice should be one that quickly and effectively kills/inactivates the agent at the lowest concentration and with minimal risk to the user. However, higher concentrations of disinfectant are necessary to clean up large spills.

    It is important to be aware that common laboratory disinfectants can be a hazard to the user. Also, once material has been treated with chemicals it cannot be autoclaved. For specific disposal information after chemical treatment contact the EHS department at ehs@ysu.edu.

  • Sewage Treatment:

    Most fluid waste can be discarded through the sanitary sewer by pouring it into a sink drain and flushing the drain with water. This includes human blood and infectious cultures as long as they have been properly decontaminated. Care should be taken to avoid generation of aerosols. The routine processing of municipal sewage provides chemical decontamination. If the fluid is contaminated with infectious agents or biological toxins, however, it must be decontaminated by chemical disinfection or steam sterilization before sewer disposal.