What kind of security is the Biosafety Cabinet in the end? I think it is air safe. The operator can breathe the safe air, the operation of the sample will not be contaminated with contaminants in the air, and the external environment will not be the sample pathogen and other risks. In order to ensure air safety, air must be ordered to flow up, and get all aspects of control. We are the most widely used A2-type biological safety cabinet as an example, one by one analysis and interpretation.
In order to ensure the safety of the operation of the sample may be the risk of space and effective isolation from the outside world, then the safety cabinet internal space must be with the outside world to maintain a certain pressure gradient, in accordance with the existing standards, A2 type biological safety cabinet pollution space should be negative pressure, or Surrounded by negative pressure space. So as to ensure that the risk of pollution is not spilled. And the core parts of the biological safety cabinet on a few: fan, high efficiency filter unit, cabinet. There are some ancillary features such as light sources. To provide a stable air flow is the main fan, right? This is the case, but in order to ensure the flow of air and pressure gradient, the design of the cabinet and the combination of high efficiency filter unit is also very important.
We often use the safety cabinets who know that the front window of the safety cabinet must be opened to a certain height, this height is basically determined. We use the fan is fixed,Biosafety Cabinet so that the unit time ventilation is also basically fixed, although not ruled out some fans can adjust the operating frequency. If the height of our front window window changes, the air volume is fixed, change the window height, also changed the area of the air inlet, then the entrance of the wind speed will change. This change in speed affects the quality of the air curtain in the operating window. Because, inside the air curtain, there are air flow from above, the flow rate of the two airflow will affect the air quality outside the cabinet and the operating space.
When the operating window at the appropriate height,Biosafety Cabinet the air inlet wind speed is about 0.5m / s or more, while the safety inside the cabinet flow rate of 0.3m / s, so that in the window will form an air curtain to ensure that the internal air flow will not overflow The But when we raise the height of the operating window, the entrance wind speed on the one hand will be reduced, and the window area increases, the wind curtain at this time unreliable, and inside the safety cabinet is likely to float out, the formation of security risks. Therefore, the safety cabinet operating procedures must still be observed.
