The selection methods for smoke exhaust fans include: selecting based on the level of noise requirements, selecting based on the required air exchange rate, selecting based on the size of oil fume, and selecting based on the size of air volume.

1. Choose based on the level of noise requirements: For high noise requirements, you can choose a rooftop fan or an environmentally friendly centrifugal fan (and there are also rooftop fans that start with wind power, which can save electricity).

2. Choose based on the required air exchange rate: Depending on the amount of air exchange required in the warehouse, you can choose a very conventional axial flow fan SF type or exhaust fan FA type.

3. Choose according to the size of the oil fume: SF axial flow fan or FA exhaust fan can be selected according to the size of the oil fume.

Secondly, for kitchens with large oil fumes that need to pass through long pipes and have bent pipes, it is strongly recommended to use centrifugal fans (4-72 centrifugal fans are very common, and 11-62 low-noise and environmentally friendly centrifugal fans are also practical). This is because centrifugal fans have higher pressure than axial fans, and oil fumes do not pass through the motor, making maintenance and cleaning of the motor easier.

4. Choose based on the size of the air volume: From a more stringent perspective on air volume requirements, a fan case is a good choice.