The biosafety cabinet is designed to protect the working personnel, laboratory environment and experimental products from exposure to the infectious aerosols and splashes that may be generated in the above operation process when operating the infectious experimental materials such as primary culture, bacterial strain and diagnostic specimen. The laboratory biosafety manual published by who clearly states that "biosafety cabinet can effectively reduce laboratory infection and cross contamination of culture caused by aerosol exposure, while biosafety cabinet can also protect the working environment". Of course, the premise of effective work of safe cabinet is to choose qualified safe cabinet and use safe cabinet correctly. At present, there are many kinds of biosafety cabinets in the market. This paper introduces the basic knowledge of biosafety standards, classification and certification of biosafety cabinets in the laboratory, aiming to provide a reference for purchasing biosafety cabinets.

◆ the selection of biosafety cabinet depends on the type of test article used in the biological test

1. If only microbial samples are involved in biological test, basic type of biosafety cabinet can be used;

2. If microbiological samples and trace chemical reagents (non corrosive) are involved in the biological test, it is necessary to use a safety cabinet equipped with discharge pipes. Because HEPA filter can not effectively filter and remove the chemical gas, if it can not be discharged, it will pose a threat to the laboratory staff and the environment.

3. If cytotoxin drugs are involved in biological test, such as various cancer treatment drugs, cytotoxin safety cabinet must be used.

◆ clearly understand the difference between biosafety cabinet and ventilation cabinet / ultra clean workbench.

The fume hood is designed to remove corrosive chemical gases and toxic fumes during chemical experiments. As there is no HEPA filter, the fume hood can not effectively remove the microbial media. Microbial samples placed in the fume hood will be spread outside the fume hood, polluting the laboratory environment.

Ultra clean bench is designed to protect the test article or product. It can prevent the test article or product from being polluted by dust or bacteria outside the work area by blowing the vertical or horizontal laminar air in the work area. Once the microbial sample is placed in the working area, the laminar air will blow the air with microbial medium to the front desk staff, which will cause danger.