Scientists have developed standards for biosafety labs to enable researchers to study contagious pathogens like SARS-CoV-2, the virus that causes COVID-19. These labs are designed to protect researchers from getting sick from the pathogens they are studying and to prevent microorganisms from entering the environment. The type of safety equipment used and the design of the lab are adapted to the level of danger connected to the types of agents being studied.There are four biosafety levels (BSLs) that define laboratory standards:
BSL-1 lab: Scientists are studying pathogens not known to cause disease in healthy adults. They require no special equipment or design.
BSL-2 lab: Researchers are exploring pathogens that have a moderate risk of causing illness if accidentally inhaled, swallowed or exposed to the skin. Safety measures include requiring the use of gloves and eyewear, as well as handwashing sinks and waste decontamination.
BSL-3 lab: In these labs, workers are studying agents that can spread through the air and cause deadly infection. Scientists must perform their work in a gas-tight, enclosed box. Other safety measures include clothing decontamination, sealed windows and specialized ventilation.
BSL-4 lab: Scientists study microorganisms that have the highest risk of causing life-threatening disease to people and animals for which no vaccine or treatment is available. Lab staff must wear full-body, air-supplied suits and shower when exiting the facility, among other safety measures.