What is the lowest Biosafety Level (BSL) that recommends using a biological safety cabinet?

The lowest Biosafety Level that recommends using a biological safety cabinet is BSL2. This level pertains to work involving moderate-risk agents that can cause human disease through ingestion or contact with mucous membranes. The use of a biological safety cabinet at BSL2 is advised to protect both the personnel and the environment from potential exposure to these pathogens, as it helps to contain aerosols and splashes that may occur during laboratory procedures.

At BSL1, while basic laboratory practices are sufficient for handling well-characterized agents that are unlikely to cause disease in healthy individuals, the use of a biological safety cabinet is not routinely required. BSL3 and BSL4 involve higher-risk pathogens requiring more stringent containment, including specialized facilities and practices, but they go beyond the minimum requirements of BSL2 regarding safety cabinet use.