How to detect the clean bench and biological safety cabinet qualified
A, Clean bench
Clean bench can protect the sample, can not protect the operators, the certification of qualified comprises the following steps:
1, using a rotary impeller anemometer and thermal anemometer measuring ultra clean air rate. Safety mean values: 0.4-0.5m/s, the maximum deviation of 20%.
2, measuring the purification table filter integrity: the use of natural wet agent detector.
3, measuring the purification table internal intensity, noise.
B, Biological safety cabinet
Biological safety cabinet at present and the research is closely related to the two level of biological safety cabinets and three stage biological safety cabinet. The two stage biological safety cabinet can be divided into several categories, but the laboratory often is the use of 30% gas efflux, type B2 70% gas circulation type A/B3 and 100% gas efflux. Biological safety cabinets can not only protect the sample can also protect the operator, so called "safe" cabinet. The detection process is as follows:
1, Into the gas flow measurement (forward volume): by thermal anemometer or DIM air bell.
2, To measure the downward gas flow: according to NSF49 and EN12469 standards are different, there are two ways. But it is the table to determine the downward airflow rate using heat wind speed.
3, ULPA filter detection: wet agent photometer, wet agent generator, pressure measuring instrument, PAO instrument.
4, There is noise, vibration intensity, intensity measurements.
5. Airflow image test , the smoke generator.