Legal analysis: The discharge port has also been standardized, and the newly-built building that can offer catering services should have a special flue in structure. When the height of the building where the catering services are located is less than or equal to 15 meters, the oil fume discharge port should be higher than the roof; When the height of the building is more than 15 meters, the height of the oil fume outlet should be more than 15 meters.

legal basis: article 81 of the law of the people's Republic of China on the prevention and control of air pollution, catering service operators who discharge oil fume shall install oil fume purification facilities and keep them in normal use, or take other oil fume purification measures to discharge oil fume up to the standard and prevent pollution to the normal living environment of nearby residents.

it is forbidden to build, rebuild or expand catering service projects that generate oil smoke, odor and waste gas in residential buildings, commercial and residential complex buildings without special flue and commercial floors adjacent to residential floors in commercial and residential complex buildings.

no unit or individual is allowed to barbecue food in the open air in the area prohibited by the local people's government or provide a venue for barbecue food in the open air.