1. Biological safety cabinet
Biological safety cabinets can provide double protection for samples and staff. The filtered clean air flow is blown down from the top of the safety cabinet, passes through the work area, and is captured before reaching the staff's breathing area. The airflow will be filtered before venting. Generally, the filtered air will be discharged back to the laboratory or exhausted to the outside through the exhaust duct. Biological safety cabinets can be divided into three categories: level 1, level 2, and level 3 to meet different biological research and epidemic prevention requirements. Level 1 biological safety cabinets can protect staff and the environment without protecting samples. The air flow principle is the same as that of a laboratory fume hood, except that the exhaust port is equipped with a HEPA filter. All types of biological safety cabinets use HEPA filters at the exhaust and intake ports. The first-level biological safety cabinet has no fan itself, and relies on the fan in the external ventilation pipe to drive the airflow, because it cannot protect the cabinet
Samples are currently less used.
The secondary biological safety cabinet is currently the most widely used cabinet type. According to the regulations of NSF49, the secondary biological safety cabinet can be divided into 4 different models according to the inlet air speed, exhaust mode and circulation mode: A1 type, A2 (formerly B3) type, B1 and B2 type. All secondary biological safety cabinets can provide staff, environment and
Protection of samples. The third-level biological safety cabinet is designed for the fourth-level laboratory biological safety level. The cabinet is completely airtight. The staff can operate through the gloves connected to the cabinet. It is commonly known as the glove box (Golve box). The test product passes through the double door. The transfer box enters and exits the safety cabinet to ensure that it is not contaminated, and is suitable for high-risk biological tests.
