Need to install. The state has regulations that the catering industry must install an oil smoke purifier to operate, which is a requirement of environmental protection. According to the provisions of Article 81 of the Book of Ming No. 123 and Article 51 and Article 52 of the Book of Ming No. 123, we would like to remind the majority of business owners investing in the catering industry to be cautious and reasonable site selection before applying for business license and catering permits and to read the following relevant articles carefully to avoid unnecessary economic losses. Air Pollution Prevention and Control Law, Article 81 of the emission of fumes of food service operators shall install fume purifiers and keep them in normal use, or take other fume purification measures, so that the fume emissions meet the standards, to prevent pollution of the normal living environment of nearby residents.