A risk assessment should be made of the microorganisms to be eliminated and the chosen disinfection compound. It is also necessary to reduce the amount of microorganisms by manual or mechanical cleaning in order to obtain a satisfactory result from disinfection. New chemical disinfectants are often combinations of different compounds. Tests made on products are often insufficient to evaluate the full antimicrobial effect of a disinfectant and in some cases the compounds in a product have a synergistic effect on microorganisms which may result in a broader antimicrobial spectrum.