Are the materials of different smoke exhaust pipes different?

The difference between exhaust pipes: the purpose of smoke exhaust is to exhaust indoor smoke to the outside through exhaust machinery, while ventilation can force indoor and outdoor air circulation through machinery. First of all, their ventilation direction and location are different. Secondly, the air quality they circulate is different, so they can't use the same pipe. Otherwise, if we accidentally put cigarettes into the room during ventilation, it will be counterproductive. Finally, the installation standards of smoke exhaust pipe and exhaust pipe are different. The range hoods of Daewoo Pipeline Manufacturing and Installation Co., Ltd. have exhaust type, that is, exhaust smoke through pipelines, and circular type (air self-circulation), which should be circular. I have never seen it. Please consult the person who bought the range hood in the shopping mall to see who has the circulating range hood, and only talk about the customization of solid wood furniture. The customization of the landlord is basically not a problem in our factory, except for the color.