What are the differences between laminar flow sampling vehicles and clean benches?

There are some differences in working principles between laminar flow sampling vehicles and clean benches, mainly reflected in the following aspects:
Airflow pattern
Laminar flow sampling vehicle: It usually adopts the airflow form of vertical laminar flow. The variable-speed centrifugal fan forces the air that has been filtered by the pre-filter in the negative pressure box into the static pressure box. Then, it undergoes secondary filtration through the high-efficiency filter. The clean air flow blown out from the air outlet of the filter passes through the working area at a certain uniform cross-sectional air velocity, carrying away dust particles and biological particles, creating a dust-free and sterile working environment. Part of the clean air circulates in the working area. Part of it is discharged to the nearby area to create negative pressure in the working area and prevent cross-contamination.
Clean bench: The airflow pattern varies depending on the type. The air in a vertical flow clean bench flows vertically from top to bottom. The air in the horizontal flow clean bench flows horizontally from the back to the working area. Clean air flows into the workbench from the top or side. After being filtered by a high-efficiency filter, it forms a vertical or horizontal laminar airflow, which flows downward or horizontally towards the exhaust port, thereby effectively expelling contaminants outside the workbench.
Application scenarios
Laminar flow sampling vehicle: It is mobile and can be flexibly used at different locations within the workshop. It is mainly used for sampling raw and auxiliary materials in the pharmaceutical, food, electronic, and other industries. It makes up for the fact that fixed laminar flow hoods, air purifiers, and other equipment cannot meet the cleanliness requirements of certain Spaces. It is suitable for occasions where sampling operations need to be carried out at different locations.
Clean bench: Widely used in fields such as biomedicine experiments, chemical analysis, electronic component assembly, clinical trials, and food safety testing, it provides a dust-free and sterile environment for these experiments and operations, prevents cross-contamination, and is suitable for long-term use in specific locations within fixed laboratories or production workshops.
Structural design
Laminar flow sampling vehicle: Generally composed of a stainless steel or powder-coated steel plate box body, it includes components such as a pre-filter, air supply unit, high-efficiency filter, lighting lamp group, diffuser plate, combined electrical apparatus, and universal casters. The upper part is the supply air static pressure box, and the lower part is the clean area. The two side baffles on the operation surface are often made of transparent glass, and the front and rear windbreak strips are made of transparent environmentally friendly plastic, which is convenient for operation and observation.
Clean bench: It is mainly composed of the box body, fan, primary filter, high-efficiency filter, power supply, etc. The workbench surface is usually made of all stainless steel and can be designed for single-sided or double-sided operation as required. It may also be equipped with devices such as anti-static ion guns. The chassis is generally made of thin steel plates, with a surface-baked paint finish. Some vertical flow clean bench fans are located at the top.
Protected object
Laminar flow sampling vehicle: It mainly protects the samples during the sampling process from contamination by the external environment. At the same time, due to the negative pressure generated in the working area, it can also prevent to a certain extent the pollutants that may be produced during the sampling process from spreading to the surrounding environment.
Clean bench: On the one hand, it protects the experimental samples or production objects on the workbench from external contamination. On the other hand, for some operations that may produce harmful gases or microorganisms, some clean benches can also protect the operators and the surrounding environment from contamination through airflow design and filtration systems. For example, the glass baffle of the vertical flow clean bench can provide certain protection.