Some misunderstandings about the cognition of biological clean safe cabinet

The biosafety cabinet is approved to provide dual protection for samples and staff The filtered clean air flow is blown down from the top of the safety cabinet, through the working area, and captured before reaching the breathing area of the staff The air flow will be filtered before venting Generally, the filtered air will be discharged back to the laboratory or out of the room through the exhaust pipe It is to clean the air environment for the test samples and test workers Pay attention to the location and common faults of the bio clean safety cabinet during operation The function of the biosafety cabinet is to protect the operator, the laboratory environment and the experimental materials when operating the infectious experimental materials such as the primary culture, bacterial strains and diagnostic specimens, so as to avoid exposure to the infectious aerosols and splashes that may be generated in the above operation process But in my daily life, I found that many people still have some misunderstandings about it:
misunderstandings 1: the hundred level purification workbench replaces the biological clean safety cabinet Most people think that these two kinds of equipment have the same shape and function, and they think that the samples they operate are common samples, which do not have high pathogenicity In fact, there are essential differences between the biosafety cabinet and the 100 level purification bench: (1) The level 100 purification bench will blow the purified air through the high-efficiency filter down the working area to protect the samples Because the working area is a positive pressure area, the air flow overflows through the operation window, only protecting the samples, but not protecting the operators and the environment If the operation contains any known or potential pathogenic aerosols, it will bring great hidden danger to the operators (2) The biosafety cabinet is a kind of negative pressure purification platform, which can prevent the operators and the environment from being exposed to the harmful aerosols produced in the laboratory process It is the cage of infectious microorganisms The correct operation of the biosafety cabinet can completely protect the operators, samples and working environment Therefore, biosafety cabinets should be used in clinical examination, diagnosis, pathological analysis, preparation of tumor drugs, biomedical research institutes and laboratories At present, the situation of replacing biosafety cabinet with clean worktable should be changed as soon as possible, otherwise, it will bring great hidden danger to medical staff and experimental researchers Mistake 2: the selection mistake of biosafety cabinet the biosafety cabinet is improper According to the different structural design, exhaust ratio and protection object and degree, the biosafety cabinet is divided into grade I, grade II and grade III, and grade II is divided into A2 and B2 Different levels of biosafety laboratories should choose different levels of biosafety cabinets, or choose appropriate cabinets according to different types of protection How to choose the appropriate level of the security cabinet has been described in detail in the previous article, here is how much Error 3: biosafety cabinet monitoring has become a blank Now, biosafety cabinet is widely used in medical and health, disease prevention and control, food hygiene, biopharmaceutical, environmental monitoring and laboratories at all levels It is an important material basis to ensure biosafety and environmental safety, and belongs to the category of "people's livelihood" measurement At present, most users don't know enough about the detection performance of the biosafety cabinet Many users think that as long as the biosafety cabinet can be turned, it will be used all the time, making it a great hidden danger In fact, the biosafety cabinet must be retested on site after installation, moving, maintenance and replacement of high-efficiency filter; in addition, the annual routine inspection and safety assessment should be carried out before it can be used without worries Placement of the location of the bio clean safety cabinet: the air flow velocity from the front opening of the bio clean safety cabinet to the cabinet is about 0.45m/s At this wind speed, the consistency of one-way flow in the cabinet is easy to be disturbed, and it is easy to be disturbed by the walking, opening windows, air supply and distribution fans and door switches of people near the safety cabinet According to the ideal arrangement, it should be placed away from activities and places that may interfere with air flow Try to leave a space of 30cm at the back and both sides of the safety cabinet for maintenance Above the cabinet, a height of 30-35cm is left to measure the wind speed of the exhaust filter and leave enough space for the replacement of the exhaust filter.