The main component of alcohol is ethanol, which is a volatile and flammable liquid. 75% alcohol can be used for surface and skin disinfection. 84 disinfectant is composed mainly of sodium hypochlorite, which is a highly effective disinfectant containing chlorine. 84 disinfectant has a strong bleaching and corrosive effect and is irritating, so it must be diluted before use and avoided in direct contact with skin and mucous membranes. Mixing 84 disinfectant with alcohol will reduce the disinfection effect of both disinfectants and will easily generate harmful and toxic substances. Due to the rapid evaporation effect of alcohol, 84 disinfectant will also evaporate rapidly. 84 disinfectant can be irritating to skin, mucous membranes and eyes if the concentration in the air is too high, causing itchy skin, coughing, sneezing, runny nose and tears in light cases and tissue or organ damage in serious cases.