Biohazards are defined as biological substances that have the propensity for causing illness, including serious and fatal diseases, in human beings. The primary categories of biohazards, recognized by the U.S. Centers for Disease Control and Prevention, are:

  • Viruses
  • Bacteria
  • Other microorganisms
  • Toxins

Within these categories are different types of biohazards. Examples of these biohazards are presented for your consideration and information. In addition, when it comes to these types of biohazards or biohazardous situations, the underlying pathogen can present a different level of risk to humans. These risk levels are also set forth for your information.

Human Blood

One of the most commonplace types of biohazards that need to be addressed with regularity is human blood. Human blood has the potential for being particularly hazardous because of the different types of bloodborne pathogens that are capable of causing serious and even fatal illness. Some of the most frequently encountered types of dangerous bloodborne viruses and bacteria include:

  • HIV
  • MRSA
  • Hepatitis B
  • Hepatitis C

Other Human Bodily Fluids

In some situations, the presence of blood is accompanied by other potentially hazardous bodily fluids. Examples of other bodily fluids (and substances) that have the propensity of containing potentially dangerous pathogens include:

  • Saliva
  • Semen
  • Vaginal Secretions
  • Breast milk
  • Urine
  • Feces

Animal Carcasses

Animal carcasses can also present a biohazardous situation for humans. For example, if a residence has an issue with rodent infestation, one of the associated risks is carcasses of these animals that have died in a residence, business, or some other location that humans occupy in some manner or otherwise access. The nature of the decomposition process results in the release of what can prove to be hazardous pathogens capable of causing illness and, in some cases, even death.

Human Remains

On a somewhat related note, decomposing human remains can also be the cause of a biohazardous matter. The human decomposition process commences the moment a person dies. As the process continues, the possibility that the scene of death will become contaminated by dangerous biohazards increases.

Common examples of situations involving human remain that present real risk of exposure to biological pathogens includes:

  • Suicides
  • Homicides
  • Traumatic accidental deaths
  • Traumatic illnesses resulting in death
  • Unattended deaths

Animal Feces, Urine, Saliva, and Other Waste

Different types of biological waste from other animals also present real threats to the health, safety, and welfare of humans. This waste includes:

  • Feces or droppings
  • Urine
  • Saliva

Rodent droppings provide a prime example of how animal waste are biohazardous substances. Rodent droppings can contain dangerous pathogens that include salmonella and the hantavirus. The hantavirus is capable of surviving in rodent dropping even after they dry out. When rodent droppings are dry, they crumble very easily. This can result in dust from these feces becoming airborne, carrying the virus along with it. A person can inhale the dust and become infected with the hantavirus. In the end, this can cause a condition known as hantavirus pulmonary syndrome, of which about 30 percent of individuals who develop this illness will die.

Microbiological Waste

Microbiological waste typically is found in a laboratory or medical setting. Examples of microbiological waste include:

  • Specimen cultures
  • Disposable culture dishes
  • Other disposable apparatuses
  • Laboratory devices
  • Discarded viruses

Pathological Waste

Pathological waste is most often found in a medical setting or in a medical examiner’s office. This type of waste exists after certain medical procedures and following autopsies. Examples of pathological waste include:

  • Unfixed human tissue
  • Unused biopsy matter
  • Anatomical parts

Sharps Waste

Finally, biohazards can include what broadly is classified as sharps waste. Sharps waste includes:

  • Needles
  • Glass slides
  • Slide coverslips
  • Scalpels
  • IV tubing with the needle in place

Bio-Hazard Risk Levels

The U.S. Centers for Disease Control and Prevention has established a four-tier system of classifying the risk presented by different types of biohazards. These risk levels are:

  • Biohazard Level 1: Biohazards that present a minimal threat to humans.
  • Biohazard Level 2: Biohazards that present a risk of severe illness in humans.
  • Biohazard Level 3: Biohazards that can cause serious, and even fatal, a disease for which treatments exist.
  • Biohazard Level 4: Biohazards that can cause serious, and even fatal, a disease for which no treatments exist.

Bio-Hazard Safety Protocols

Whenever contact is to be made with any type of biohazardous substance, specific safety protocols must be followed, including for bio-hazard cleanup. At the heart of this safety, protocols are the use of personal protective equipment rated or designed for people who will have contact with biohazards. No one should have contact with biohazardous material without using this personal protective equipment. This gear includes:

  • HEPA mask or respirator
  • Protective eyewear
  • Durable gloves
  • Smock or uniform

Armed with this basic information about different biohazards and the risk levels presented by these potentially harmful and even deadly substances you’re in a better position to understand how to protect yourself and your loved ones should you encounter one of the situations described here.


Emily Kil

Co-Owner of Eco Bear Biohazard Cleaning Company

Together with her husband, Emily Kil is co-owner of Eco Bear, a leading biohazard remediation company in Southern California. An experienced entrepreneur, Emily assisted in founding Eco Bear as a means of combining her business experience with her desire to provide assistance to people facing challenging circumstances. Emily regularly writes about her first-hand experiences providing services like biohazard cleanup, suicide cleanup, crime scene cleanup, unattended death cleanup, and other types of difficult remediations in homes and businesses.