1, exhaust pipe and exhaust fan and grease purifier and other ancillary equipment installed in the design and connection is unreasonable: most of the kitchen exhaust fan will be used axial fan, fan and exhaust pipe and grease purifier connection using hard connection. Axial fan noise itself is large, about 85 ~ 90dD and pipeline and fume purification equipment using duct connection, fan motor rotation will drive the pipeline and fume purification equipment together with the vibration noise. General kitchen exhaust pipe wind speed design wind speed are too fast, in the exhaust air outlet without the expansion of the duct mouth directly to the dense louvers. Fans, pipes, smoke purification noise plus the noise of the pipeline airflow and dense louvered blade vibration noise combined with the noise generated by the noise is quite large.

2, pump room and freezer room are located in the top of the restaurant: the pump room of the vibration generated by the operation of the pump, the noise is sometimes small and repeated non-stop with the freezer pipe noise vibration combined with the floor vibration. Through the wall spread into the restaurant.

3, smoke exhaust pipe restaurant top: smoke exhaust pipe plate thickness is not enough, pipe section is too long. Smoke exhaust purification system in the work of suction air flow will make the pipe deformation and noise. The pipe elbow does not use a noise-reducing elbow.

The above situations are the inevitable result of the restaurant or guest room noise. It can make the restaurant fume purification smoke-free direct emission, barbecue black smoke smoke-free emission. It is a new industry of environmental protection. Oil smoke purification equipment removal rate of 95% or more.