DEVELOPMENT OF LONG LIFE ANTIFOULING PAINTS AND SHIPBOARD EVALUATION

Abstract

ABSTRACTThis paper is an account of selected events in a technology exchange over a period of years that have led to the development, by the Navy, of improved evaluation procedures and new antifouling paint formulations potentially capable of five year service. It begins with the Navy's publication in 1952 of “Marine Fouling and Its Prevention.” At the time, the evaluation of new antifouling paints relied primarily on the exposure of test panels at marine sites in various locations. To reduce the variations in panel tests results, populations of barnacles were raised in the laboratory from the embryo to adult form to investigate various modes of physical and chemical fouling control. Bioassay populations of barnacles, both as larvae and adults, used to assess a large number of toxins, led to the selection of organometallic compounds as an effective toxic component in a new generation of antifouling paints. New paint formulations, based on various toxic release mechanisms, exhibited enhanced antifouling capability. These paints were used with improved epoxy paints formulated by the Navy to control corrosion. The need over the past decade to conserve fuel has led to new concepts for the underwater maintenance of hull coating systems. The advancing underwater diving technology has made available underwater multibrush cleaners and diver held power tools. Shipboard evaluation of experimental antifouling hull coating systems has brought about the application of new ship survey and inspection procedures assisted by improving underwater color photography.