Biosafety cabinets are isolation barriers for laboratory biosecurity.

The biological clean safety cabinet serves as an isolation barrier for laboratory biosecurity, offering dual protection for samples and personnel. Its operating principle primarily involves drawing air out of the cabinet to maintain a negative pressure inside, with external air being filtered through a high-efficiency air filter before entering the safety cabinet to prevent contamination of the samples being handled. The air inside the cabinet also needs to be filtered through a high-efficiency filter before being released into the atmosphere, to safeguard the environment.

Biological safety cabinets typically consist of two main components: the cabinet and the stand. The cabinet section primarily includes the following structures:

1. Air Filtration SystemThe system consists of driven fans, air ducts, recirculating air filters, and exhaust air filters, continuously introducing clean air into the workspace. It ensures that the downward airflow (vertical airflow) in the work area maintains a speed of not less than 0.3m/s, guaranteeing a cleanliness level of 100 in the workspace. Additionally, it purifies the exhaust air flow, preventing environmental contamination. The core component is the High-Efficiency Particulate Air (HEPA) filter, which achieves a filtration efficiency of 99.99% or higher for particles as small as 0.3μm. The pre-filter hood or pre-filter at the air intake can extend the lifespan of the HEPA filter.

2. External Exhaust Box SystemThe unit consists of an exhaust casing, a fan, and exhaust ducts. The external exhaust fan extracts impure air from the workspace, creating a negative pressure inside due to the exhaust effect. This prevents the escape of air from the work area, thereby protecting the operator.

3. Slide-Forward Window Drive SystemThe assembly consists of a front glass door, door motor, traction mechanism, drive shaft, and limit switches, primarily functioning to drive or tow the door shafts, ensuring the front glass door remains in its proper position during operation.

4. Lighting Sources and UV SourcesInside the glass door, it ensures adequate brightness in the workspace and is used for disinfecting the work surface and air within the studio.

5. Control PanelEquipped with power supply, UV lights, lighting fixtures, fan switches, and controls for moving the front glass door, it is primarily used for setting and displaying system status.