What does the Biohazard Symbol mean?

The Biohazard symbol does not go unnoticed. Its appearance reflects its message: danger! You will find this sign in medical practices and in industrial sites.

This article explains in depth what is behind the symbol, how it was created, and why it is essential to respect it.

What’s the Story Behind the Biohazard Symbol?


The research team was comprising scientists and engineers from DOW Chemical in the United States. They began this mission in 1966. At the time, there was no consensus on the use of visual language to communicate the biohazard. The latter was increasingly common in research, industry, and the military. The team worked on creating a symbol or icon that would keep its meaning across time and cultures. As a first step, the team established the factors for choosing a new symbol:

  1. To catch the eye
  2. Do not be ambiguous
  3. Getting your message across easily
  4. Be simple to stencil design
  5. Be symmetrical for easy identification from any angle
  6. Be recognized by as many people as possible

In the first phase, the research team recruited 300 people from 25 American cities. Participants assessed the meaning of existing symbols. One week later, 60 symbols, including the 24 original and 36 new ones, were presented to the same people. This time, participants had to recognize the symbols seen in the first phase. It created a memorability rating.

The winning symbol had a low score on its meaning and a high score on its memorability. A symbol visually speaking but without a meaning already assigned. It was perfect. More than 50 years later, it is still used to communicate biohazard around the world.

Symbol Display Rule

Biological agents such as bacteria, fungi, and viruses can cause illnesses in humans:

  • Infections
  • Intoxication
  • Allergies
  • Cancer

Risk assessment is carried out by following the chain of transmission. Risk prevention consists of breaking this chain as far upstream as possible.

Prevention involves measures for:

  • Work organization
  • Collective and individual protection
  • Staff information and training

Bio-hazardous Materials and Waste Categories

There are five categories of biohazardous waste currently recognized by the University of Tennessee:

  • Biohazardous solid waste
  • Biohazardous sharps
  • Liquid biological waste
  • Pathological waste
  • Soil collection, treatment, and disposal

Subculture Symbol Use

Beyond industrial facilities and medical waste storage, the symbol has been introduced into modern cultural groups. There is often more than a touch of irony in this use.

The LGBTQ community uses the symbol as a tattoo. It refers to HIV/AIDS infection. But it is most often used by hardcore or metal bands.

Contact Crime Scene Intervention Now!

If you witness a situation that requires biohazard clean-up services, contact Crime Scene Intervention. You can call us 24 hours a day, 7 days a week at 561-250-0822 for urgent assistance.

In the event of a biohazard, it is essential to leave this task to the experts. The biohazard symbol was created for a specific reason: to keep it out of harm’s way.