Based on our survey, we introduced here Denkaisui (electrolyzed water)-producing apparatus that produce
hypochlorous acid water as the food additive and its equivalent water. The report also include types of apparatus that
produce the following waters with high level of anti-microbial activity; strongly acidic (pH2.2-2.7), weakly acidic
(pH2.7-5.0), slightly acidic (pH5.0-6.5), neutral (pH6.5-7.5) and slightly alkaline (>pH7.5).
The manual for the gastrointestinal endoscope-washing and disinfecting apparatus using functional water as medical instruments with governmental approval was introduced and its significance and assignments were reviewed.