Disinfectants are chemical substances used to destroy virus and germs such as bacteria and fungi. They work by destroying the cell wall of microbes or interfering with their metabolism. It is also a form of decontamination whereby chemical methods are used to reduce the amount of pathogenic organisms on a surface.
The U.S. Environmental Protection agency (EPA) treats disinfectants as pesticides and requires all disinfectants to be registered with the US EPA for sale in the United States. The selection of disinfectant should be based on the function the disinfectant is expected to perform. You should always consider the effectiveness against the potential pathogenic agent, the level of toxicity to humans, the dwell time, impact on the surface to be disinfected, the effects on the environment and the expense.