A Biosafety Cabinet (BSC) is a ventilated laboratory workspace designed to provide a safe working environment when handling pathogenic microorganisms, hazardous biological materials, or potentially infectious agents. These cabinets are essential in microbiology, biomedical, pharmaceutical, and research labs, where the risk of contamination, both to the sample and the operator, must be minimized.

The primary purpose of a biosafety cabinet is to protect the operator, the environment, and the specimen from biological exposure. It achieves this through a high-efficiency particulate air (HEPA) filtration system, which traps airborne particles and contaminants. Airflow patterns within the cabinet are strictly controlled to avoid any cross-contamination.

There are three main classes of BSCs (Class I, II, and III), each designed to provide a different level of protection. Class I cabinets offer protection to personnel and the environment but not the sample. Class II cabinets, the most commonly used, provide protection to personnel, environment, and the sample. Class III cabinets are gas-tight and offer the highest level of protection, typically used when working with highly infectious agents.

In addition to airflow and filtration, biosafety cabinets are constructed with stainless steel interiors, seamless corners, and UV lighting options for sterilization. They also include sash windows or shields to act as a physical barrier between the operator and the work area. Proper usage, maintenance, and certification of BSCs are critical to maintaining safety and performance.