China National Standard GB50346 specifies that the secondary Laboratory for biosafety (P2) is mainly used in general biological hazard level research, health service, diagnosis, etc. The biological hazard level of the laboratory is secondary (medium individual hazard, limited group hazard). It is suitable for pathogenic factors with medium potential hazards to human body, animals, plants and the environment. It is specifically defined as "health". Kang adults, animals and the environment will not cause serious harm, with effective prevention and treatment measures, and limited risk of transmission, "on behalf of pathogens: influenza virus, African swine fever and so on.
China National Standard GB50346 stipulates that BSL-2 laboratory B1 does not need negative pressure, B2 needs negative pressure environment, and the definition of pathogenic biological factors a, B1 and B2 in technical specifications is as follows: "Biosafety laboratories can be classified into a and B categories according to the transmission routes of pathogenic biological factors operated by them. Category A refers to the laboratory that operates non-air-borne biological factors, and Category B refers to the laboratory that operates air-borne biological factors. Class BL biosafety laboratory refers to the laboratory that can operate effectively with the safety isolation device; Class B2 biosafety laboratory refers to the laboratory that can not operate effectively with the safety isolation device."
Then the question arises: how to understand the effective use of safety isolation devices for operation? Is the biosafety cabinet a safety isolation device? How to distinguish b1 from b2? This problem can be understood as follows: the biosafety cabinet belongs to the safety isolation device, but it is not necessarily an effective isolation device. Because even 100% full-row biosafety cabinets have spillover risk, and some biosafety cabinets use circulating air, even with high-efficiency filters, there is a limitation of efficiency, so biosafety cabinets are not completely effective isolation, the key is to see the type of biosafety cabinets and the risk of operating objects.
If the laboratory mainly does some microbial detection of food, does the pathogenic bacteria laboratory need to be set to BSL-2 type b2? There is no uniform answer to this question. If African swine fever is involved, it is not only BSL-b2, but ABSL-b2. However, due to technological advances, the cost of BSL-2 laboratories is not very different. If conditions permit, it is recommended to do ABSL-b2 level, which can fully meet the requirements of all food microbial detection.
In addition, can two or more biosafety cabinets be placed in a pathogenic bacteria laboratory workshop? The biosafety cabinet is discharged into the room without drainage pipes. This depends mainly on the operation needs and does not limit the number, but there should be no air outlet near the operating surface of biosafety cabinet or other places where aerosols are produced, because it will destroy the flow direction of air in biosafety cabinet and indoor, leading to the diffusion of pollutants.