If you are like most people, you have a basic understanding that blood and other bodily fluids can contain dangerous pathogens. These are known as biohazards.

If you are also like many people, you may wonder if dried blood is dangerous. You may wonder why dry blood is classified by some people as a biohazard.

Definition of Biohazard

A biohazard is defined as a dangerous biological substance. This type of biological substance poses a very real threat to the health of human beings. Exposure to certain types of biohazards can be fatal. In addition, biohazards can be dangerous to other animals and can cause harm to the environment for generally. Biohazards include:

  • Bacteria
  • Viruses
  • Microorganisms
  • Toxins (derived from a biological source)

The Most Common Dangerous Bloodborne Pathogens

There is a trio of bloodborne pathogens that are most common. These are:

  • HIV
  • Hepatitis B
  • Hepatitis C

The Importance of Personal Protective Gear

The U.S. Centers for Disease Control and Prevention became involved in the development of appropriate protocols for personal protective gear in cases potentially involving bloodborne pathogens. In addition to proper training and experience, a person involved in biohazard remediation must have proper personal protective gear or PPE. This gear includes:

  • Mask
  • Goggles
  • Gloves
  • Apron, uniform, or smock

Do the Most Common Bloodborne Pathogens Survive Blood Drying?

In a word, no. If blood is completely dry, HIV, hepatitis B, and hepatitis C viruses are also thought to die as well. The same generally holds true for some of the less common bloodborne pathogens as well.

With this being factual, another reality is that pathogens of different types can morph over time. While nothing in this explanation is intended to be alarmist, in the final analysis, no one can state without reservation that the time might come in which dried blood could harbor a dangerous and living pathogen.

What is even of a greater concern is the fact that what a person thinks is dried blood may not, in fact, be completely dry. If blood is not thoroughly dry, there is a real possibility that it still contains living, dangerous pathogens like HIV, hepatitis B, hepatitis C, or something more dangerous.

These two possibilities demand that you take precautions even when you are cleaning up what you think is dry blood. Yes, if it is dry, the blood may be harmless. Although this is something of a cliché, the reality is that you are better safe than sorry if you are faced with the prospect of cleaning up dry blood.

Other Biological Contamination

Just because you believe blood may be dry and safe doesn’t mean that there are no other biohazards that might threaten your health and wellbeing. Bloodborne pathogens are capable of contaminating other biological materials, including different types of bodily fluids and tissue. Thus, if you identify dry blood, and are unsure of what else might be present in an area, you need to utilize universal precautions and personal protective gear.

Situations Requiring Professional Assistance Cleaning up Blood

Understanding the potential risks that are presented by blood, bodily fluids, and other biological material, you need to appreciate when it is necessary to engage personal assistance in cleaning up the blood. A basic rule of thumb is that you should not clean up blood on your own if the area containing blood is larger than a dinner plate. The only possible exception would be if the blood was your own. In the alternative, if the blood was the result of an accident involving a family member, you face a lower risk of cleaning it up. However, you should still use personal protective equipment.

Due to the dangerous nature of certain types of biohazardous pathogens, you probably do not have the background to safely and effectively undertake significant blood cleanup.

The most common situations in which professional biohazard cleanup are needed include:

  • Accidental death
  • Traumatic injury
  • Suicide
  • Homicide
  • Other types of violent crime
  • Unattended death

Depending on the situation that gave rise to the presence of blood and bodily fluids, dangerous pathogens might be found “hidden.” Even if the blood on a surface presents as dry, underneath the surface wet blood and other bodily fluids might have seeped or migrated. A prime example is a situation in which a person dies an unattended death that is not immediately discovered. Although blood may appear to have dried, the scene is likely rife with highly dangerous biohazardous substances.


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.