Single-chain quaternary ammonium salts do not work, while double-chain quaternary ammonium salts can destroy coronaviruses. There are two types of quaternary ammonium salts with very different properties. One category is called single-chain quaternary ammonium salts, typically represented by benzalkonium chloride. It is subordinated to low-level disinfectants in terms of functional classification of disinfection and is not usually used to kill viruses. Another category is called double-chain quaternary ammonium salts, typically represented by bis-decyl dimethyl ammonium chloride, bis-decyl dimethyl ammonium bromide, from the disinfection of the functional classification belongs to the medium level disinfectant, with a broad spectrum of virus disinfection components. The quaternary disinfectants sold in China are usually compound quaternary ammonium salts, and in this time, the guidelines for protection of public places issued by the Health and Welfare Commission and the Chinese Journal of Disinfection, also clearly put compound quaternary ammonium salts as disinfectants available for the prevention of new coronaviruses.