Precautions
1. In order to avoid cross-contamination between items, the items needed during the whole work process should be lined up and placed in the safety cabinet before the work starts, so that no items need to be taken out through the air flow compartment before the work is completed or Put it in, pay special attention: no items can be placed on the front and rear return grills to prevent the return grills from being blocked and affecting the air circulation.
2. Before starting work and after finishing work, it is necessary to maintain the air circulation for a period of time to complete the self-cleaning process of the safety cabinet. The cabinet should be cleaned and disinfected at the end of each test.
3. During the operation, try to reduce the number of arms in and out as much as possible, and the arms should be slow when entering and exiting the safety cabinet to avoid affecting the normal airflow balance.
4. The movement of items in the cabinet should follow the principle of moving from low pollution to high pollution, and the experiment operation in the cabinet should be carried out from the clean area to the polluted area. Before operation, a towel soaked with disinfectant can be used as a bottom to absorb any droplets that may spill.
5. Try to avoid placing centrifuges, oscillators and other instruments in a safety cabinet to prevent the particulate matter on the filter membrane from shaking off when the instrument shakes, resulting in a decrease in the cleanliness of the cabinet; at the same time, the airflow of the heat dissipation vents of these instruments may affect the cabinet. The airflow balance.
6. No open flame can be used in the safety cabinet to prevent the high temperature and fine particles generated in the combustion process from being brought into the filter membrane and damage the filter membrane.
Maintenance of biological safety cabinet
In order to ensure the safety of the biological safety cabinet, the safety cabinet should be maintained and maintained regularly:
1. The working area of the safety cabinet should be cleaned and disinfected before and after each use.
2. After the service life of the HEPA filter expires, it should be replaced by a professional who has received special training in biological safety cabinets.
3. The laboratory biosafety manual promulgated by WHO, the U.S. biosafety cabinet standard NSF49 and the China Food and Drug Administration biosafety cabinet standard YY0569 all require one of the following conditions, the biosafety cabinet should be tested for safety: the installation is completed and put into use Before; annual routine inspection; when the safety cabinet is shifted; after replacing the HEPA filter and repairing internal parts.
Safety inspection includes the following aspects:
1. Inlet flow direction and wind speed detection: Inlet flow direction is detected on the working section by smoke method or silk thread method. The detection position includes the periphery and middle area of the working window; the wind speed of the intake flow is measured by an anemometer.
2. Downward airflow wind speed and uniformity detection: use an anemometer to measure the cross-sectional wind speed evenly.
3. Cleanliness detection of working area: adopt dust particle timer to detect in working area.
4. Noise detection: The horizontal center of the front panel of the biological safety cabinet is 300mm outwards and 380mm above the work surface to measure the noise with sound level.
5. Illuminance detection: set a measuring point every 30cm along the center line of the length of the worktable.
6. Leakage detection of the cabinet: Seal the safety cabinet and pressurize it to 500Pa. After 30 minutes, connect a pressure gauge or pressure sensor system in the test area to detect with the pressure decay method, or use the soap bubble method.