Biological hazard Facts for Kids

This shape is used all over the world to tell people of a biological hazard.

A biohazard is something biological that can be harmful to living things, especially people. This could be a tiny living thing like a microorganism or virus, or a harmful toxin. It can make people or animals sick.

The word 'biohazard' and its special symbol are used as a warning. They tell people to be careful around these substances. The biohazard symbol was created in 1966 by Charles Baldwin. He was an engineer working for the Dow Chemical Company. The symbol helps label biological materials that could be dangerous. This includes samples of viruses or used hypodermic needles. You can even find the biohazard symbol in computer text as U+2623 (☣).

What do biohazard signs mean?
How biohazards are grouped for transport
Understanding biohazard levels
See also

What do biohazard signs mean?

Special signs and labels help us understand how dangerous a biohazard is. These signs use different colors and words to show the risk level. This helps people quickly know how serious a biohazard is from a distance.

DANGER: This sign means the biohazard will cause death. It uses a black biohazard symbol on a red or white background.
WARNING: This sign means the biohazard might cause death. It uses a black biohazard symbol on an orange or white background.
CAUTION: This sign means the biohazard will cause injury, but not death. It uses a black biohazard symbol on a yellow or white background.
NOTICE: This sign gives important information about hygiene or lab rules. It uses a black biohazard symbol on a green or white background.

These rules for signs are used in many places, including workplaces in America. They help keep everyone safe.

How biohazards are grouped for transport

Biohazardous materials are also grouped into different categories for safe transport. These groups help people know how to handle them when they are moved from one place to another.

Category A (UN 2814): These are infectious substances that can cause serious or deadly diseases in humans or animals.
Category A (UN 2900): These are infectious substances that mainly affect animals, but usually not humans.
Category B (UN 3373): These are biological substances sent for testing or research.
Regulated Medical Waste (UN 3291): This includes waste from medical treatments or research that could be harmful.

Understanding biohazard levels

Immediate disposal of used needles into a sharps container is standard procedure.

NHS medics practice using protective equipment used when treating Ebola patients

The United States Centers for Disease Control and Prevention (CDC) sorts diseases into different biohazard levels. Level 1 is the lowest risk, and Level 4 is the highest risk. Labs and other places are also given a Biosafety Level (BSL) from 1 to 4. Sometimes, they are called P1 through P4.

Biohazard Level 1

This level includes bacteria and viruses that cause very little risk.
Examples are Bacillus subtilis, canine hepatitis, Escherichia coli, and chickenpox. Some cell cultures and non-infectious bacteria are also at this level.
When working with these materials, people usually wear gloves and some face protection.

Biohazard Level 2

This level includes bacteria and viruses that cause only mild sickness in humans. They are also hard to catch through the air in a lab.
Examples are hepatitis A, hepatitis B, hepatitis C, some influenza A types, Lyme disease, salmonella, mumps, measles, and HIV.
Regular tests with patient samples can be done safely at this level. More complex research might need a special lab (BSL-2) but with stricter safety rules (BSL-3 practices).

Biohazard Level 3

This level includes bacteria and viruses that can cause serious or deadly diseases in humans. However, there are vaccines or treatments for them.
Examples are anthrax, West Nile virus, SARS coronavirus, MERS coronavirus, SARS-CoV-2, H5N1 flu, tuberculosis, yellow fever, and malaria.
Working with these materials requires special safety equipment and procedures.

Biohazard Level 4

This is the highest level. It includes viruses that cause severe or deadly diseases in humans, and there are no vaccines or treatments available.
Examples are Bolivian hemorrhagic fever, Marburg virus, Ebola virus, Lassa fever virus, and other hemorrhagic diseases.
Even smallpox is handled at this level, even though there's a vaccine. This is because it has been wiped out, so most people are not vaccinated anymore.
When dealing with these biohazards, scientists must wear a special suit that has its own air supply.
Level 4 labs have many safety features. These include multiple showers, a vacuum room, and ultraviolet light rooms. They also have special systems to detect hazards.
Multiple airlocks are used, and doors are locked electronically so they cannot both open at the same time.
All air and water going into and out of a Level 4 lab are cleaned to make sure no biohazards can escape.
Currently, no bacteria are classified at this level.

Biological hazard facts for kids

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