The difference between clean bench and biological safety cabinet

1. The biological safety cabinet is to suck air into it to prevent biological germs or reagents from spilling out of the safety cabinet to contaminate the laboratory and laboratory personnel, and is mainly used to protect the human body.

2. The ultra-clean workbench is an instrument to ensure the sterile environment of the test bench, regardless of the laboratory and laboratory personnel.

3. Biological safety cabinet is a safety equipment widely used in scientific research, teaching, clinical inspection and production in the fields of microbiology, biomedicine, genetic recombination, animal experiments, biological products, etc. It is also the first-level protection in laboratory biosafety. Basic safety protection equipment in the barrier.

4. The biosafety cabinet is a negative pressure purification workbench. Correct operation of the biosafety cabinet can completely protect the staff, the tested samples and prevent the occurrence of cross-contamination; while the ultra-clean workbench only protects the operating object but not the protection. Clean benches for staff and laboratory environments. Therefore, in the research, teaching, clinical inspection and production of microbiology and biomedicine, biological safety cabinets should be selected and used, but ultra-clean workbenches should not be selected and used.

Extended information about the clean bench

The principle of the ultra-clean workbench is that in a specific space, the room air is pre-filtered by a pre-filter, pressed into the static pressure box by a small centrifugal fan, and then filtered by a high-efficiency air filter for the second stage, and then blown out from the air outlet of the high-efficiency air filter. The clean air flow has a certain and uniform cross-sectional wind speed, which can remove the original air in the working area and take away dust particles and biological particles to form a sterile and high-clean working environment.

Notes on clean benches and biological safety cabinets

The service life of the ultra-clean bench is related to the cleanliness of the air. In temperate regions, the clean bench can be used in general laboratories. However, in tropical or subtropical regions, due to the high amount of pollen in the atmosphere, or the dusty areas, the clean bench should be placed in a better room with double doors. . Under no circumstances should the air inlet hood of the ultra-clean bench face an open door or window, so as not to affect the service life of the filter.

The ultraviolet lamp can also be hoisted on the ultra-clean workbench, but it should be installed outside the lighting lampshade, and the arrangement of the lighting lamps should be staggered, so as not to hinder the lighting during work. Do not put the UV lamp into the lampshade (glass plate), because the UV light cannot penetrate the glass, and its lamp tube is quartz glass, not silicate glass.

Biological safety cabinets can be divided into three categories: first-class, second-class and third-class to meet different biological research and epidemic prevention requirements.

Class I biological safety cabinets protect workers and the environment without protecting samples. The airflow principle is the same as that of a laboratory fume hood, except that the exhaust port is fitted with a HEPA filter. All types of biological safety cabinets use HEPA filters on the exhaust and air intake. The first-class biological safety cabinet itself has no fan, and relies on the fan in the external ventilation duct to drive the airflow. Since it cannot provide protection for the test product or product, it is rarely used.

Class II biological safety cabinets are currently the most widely used cabinet types. Like Class I biological safety cabinets, Class II biological safety cabinets also have airflow into the front window opening, called "air intake", to prevent the escape of aerosols that may be generated during microbial manipulation through the front window. Unlike Class I biological safety cabinets, the unfiltered intake air will be captured by the intake grille before reaching the work area, so the test item will not be polluted by the outside air.