Biohazards: Four-Level Safety Classification
A biohazard can be classified into one of four categories, depending on its risk to humans.
1. Biosafety Level 1 (BSL-1)
This category includes agents that pose a low risk to human health. BSL-1 agents can cause infection but are not life-threatening. Examples of BSL-1 biohazards include Escherichia coli and Staphylococcus aureus. These agents are often found on the skin or the respiratory tract and can cause infections if they enter the body through cuts or mucous membranes. These biohazards are not typically fatal.
When working with BSL-1 biohazards, workers do not have to work in separate buildings, and they do not need to wear special protective equipment. They do, however, need to wear PPE such as eyewear protection, gloves, lab coats, etc.
All surfaces and objects that have come into contact with the biohazardous material should be disinfected each time after work is finished. The area should also be aired out to allow the biohazardous material to dissipate.
2. Biosafety Level 2 (BSL-2)
This category includes agents that pose a moderate risk to human health. BSL-2 agents can cause serious infections, and though they are not typically life-threatening, special safety precautions are necessary when dealing with this type of material.
Some examples of BSL-2 agents include:
Certain bacteria, such as those that cause tuberculosis
Viruses, such as the flu
Fungi, such as candida
Parasites, such as hookworm
Workers dealing with Biosafety Level 2 (BSL-2) agents take precautions to protect themselves and others from exposure to hazardous material. This may include wearing the right equipment such as gloves, face masks, and hazmat suits.
When disinfecting BSL-2 areas, biohazard cleanup crews also use professional equipment to clean up any potential biological hazard, such as disinfectants and vacuums with high-efficiency particulate air (HEPA) filters.