6) Establish verification procedures These procedures are activities, other than monitoring, that determine the validity of the HACCP plan and that the system is operating according to the plan. An important aspect of verification is to determine if the plan is scientifically and technically sound. Also, that all the hazards have been identified and that, if the HACCP plan is properly implemented, these hazards can be effectively controlled. Verification can be accomplished by expert advice and scientific studies and observations of the flow of food, measurements and evaluations. Another means of verification is an on site review of the established critical limits. Each CCP will have one independent authority. This verification step provides an opportunity to make modifications to the plan if necessary.