84 disinfectant expired can not be used. 84 disinfectant mainly with sodium hypochlorite as the main component of chlorine disinfectant. Usually used for object surface and environmental disinfection, the use of attention to good protection, do not directly touch the disinfectant. Secondly, sodium hypochlorite has a strong oxidizing property, which can be hydrolyzed to generate hypochlorous acid with strong oxidizing property, thus it has the effect of oxidizing the reducing substances, and finally it can make the microorganisms lose their functions, and they can’t reproduce or be infected. After the production of 84 disinfectant has a certain expiration date. If the expiration date is exceeded, the sodium hypochlorite may not be hydrolyzed to produce hypochlorous acid during use, which will weaken or disappear the effect of sodium hypochlorite, and therefore it will not be able to play a disinfecting role. At the same time, if contact with expired 84 disinfectant, may also cause the body nausea, vomiting, diarrhea and other symptoms, so 84 disinfectant expired can not be used.