Manual of Naval Preventive Medicine
Chapter 1: Food Service Sanitation
Section II: Standards and Sanitation of Food Service Equipment and Utensils

1-10. Dishwashing Agents.

Department of the Navy
Bureau of Medicine and Surgery

1. Detergents. The proper use of an effective detergent for dishwashing is necessary to effectively remove soil from the dishes and prevent the buildup of films and residues. The efficiency of the detergent is affected by the degree of hardness of the water. Different detergents are available for hard and soft waters. Preference should be given to a detergent demonstrated to be effective with the particular water supply used. Water hardness is the critical factor in determining the type and amount of dishwashing compound to use. Water produced by the ship's distilling plants is always very soft. Water furnished from the pier is always harder. Water from the pier and water provided to shore stations will vary greatly depending on the location. The Engineering/Public Works Department may be contacted for information concerning the hardness of the local water, if necessary.

2. Detergent Feeding. Detergent must be added to dishwashing machines. It can be added manually; however, automatic dispensers are highly recommended. The proper amount of detergent will depend on the capacity of the tank and hardness of the water. Too little or too much detergent is almost as undesirable as none at all, yet the maintenance of the proper detergent concentration is one of the most overlooked steps in dishwashing. The type of detergent which is compatible with the degree of hardness of the water must be used. The machine operator should be instructed by his supervisor regarding the proper amount of detergent to be added to the machine. It is usually necessary to add one-fourth of the original amount every 10 minutes to compensate for dilution and increasing food particle load. Care must be taken to avoid feeding too much detergent which causes carryover to the rinse tank and may result in retention of detergent on the utensil surfaces.

3. Unauthorized Dishwashing Agents. General purpose cleaning agents which do not specifically state, on the label, that the intended use is for food-contact surfaces will not be used for cleaning dishware and utensils. Furthermore, hand dishwashing compounds must not be used in dishwashing machines and dishwashing machine detergent will not be used for manual dishwashing.