Biological Safety Cabinet (BSC)
Also known as a biosafety cabinet or microbiological safety cabinet, a Biological Safety Cabinet (BSC) is a specialized containment device used in laboratories, healthcare facilities, and research settings to provide protection for personnel, the environment, and the samples or materials being handled.
The primary purpose of a BSC is to create a controlled, sterile, and safe working environment for working with biological agents, hazardous materials, and microorganisms.
Refer to the example of the biological safety cabinet airflow diagram on a right.
Key Features and Functions
-
Containment
BSCs are designed to provide containment by creating a physical barrier between the operator and the materials being manipulated inside the cabinet. The cabinet has a front opening with a transparent sash or window that allows the operator to access the workspace while maintaining a sealed environment.
-
Airflow
BSCs use high-efficiency particulate air (HEPA) filters to create a laminar airflow within the cabinet. This airflow protects the operator and prevents the escape of contaminants by drawing in air from the surrounding environment, filtering it through the HEPA filters, and directing the clean air downward onto the work surface.
-
Protection Levels
BSCs are classified into different types and protection levels based on their design, airflow patterns, and applications. The most common types include Class I, Class II (Types A1, A2, B1, B2), and Class III. Each type provides varying degrees of personnel, environmental, and sample protection.
-
Safety Features
BSCs are equipped with various safety features to enhance operator safety and prevent contamination. These features may include alarms for airflow disruptions, door openings, filter saturation, and UV light operation. Some BSCs may also have interlock systems that ensure proper sash position and prevent operation in case of safety breaches.
-
Work Surface
The work surface of a BSC is typically made of stainless steel to facilitate easy cleaning and decontamination. It may have a raised grille or perforated surface to ensure uniform airflow distribution and to capture spills or aerosols that may occur during work.
-
Exhaust System
BSCs are connected to an exhaust system that removes filtered air from the cabinet and discharges it safely outside the building. This prevents the recirculation of potentially contaminated air and maintains a clean environment within the laboratory or facility.
-
Sterilization
Some BSCs may have built-in UV lamps that emit ultraviolet light to provide additional sterilization of the work area between uses. UV light exposure helps in decontaminating the surfaces and minimizing microbial contamination.