Differences between ducted fume hood, clean bench and biosafety cabinet

In the layout of the laboratory, there are often general equipment such as fume hoods, biological safety cabinets and ultra-clean workbenches. It is easy to be confusing as to where these devices are installed.

1. Ducted lab fume hood

The fume hood draws air from indoors and discharges it to the outside. The purpose is to ensure that the pollutants generated in the work area will not spread to the interior. The function is just the opposite of the ultra-clean workbench. It draws air from the indoor and discharges it to the outside. The air is drawn from the room, so if the indoor environment is not very good, it will also contaminate the sample. Its function is mainly to protect the indoor environment and personnel. It is generally used in volatile, radioactive, toxic and harmful experimental operations or instruments, which can prevent these harmful substances from spreading to indoor hazards.

2. Ultra-clean workbench

The ultra-clean workbench is to provide a local clean environment. Its principle is to draw air from the room, after filtering, to send it to the work surface, and then to the room after passing through the work surface, it can only create a clean environment, and this environment is used to protect the samples. , After the indoor air is filtered and sent to the working area of the sample, it will return to the room, so that if the sample releases some pollutants, it will contaminate the room. Ultra-clean benches are generally used in the biological field to create some local 100-level environments.

3. Biological safety cabinet

The biological safety cabinet is relatively complex. It draws air from the room, but the drawn air will be filtered by the filter and then sent to the working area, and then some air will be discharged. The environment in the sample area is protected by the filter and forms a negative The high-pressure airflow protects the room and prevents pollution from leaking, so it can not only protect the sample, but also avoid the pollution of the sample from leaking and polluting the environment and personnel, and according to different types, it is also divided into different exhaust methods. For volatile samples, an efflux-type biological safety cabinet is required. If it is purely biologically hazardous, an indoor biological safety cabinet can be used. Biological safety cabinets are generally used in the field of pathogenic microorganisms to prevent the leakage of pathogenic microorganisms and protect pathogenic microorganisms from outside air pollution.