A water based defoamer is a type of chemical additive designed to reduce or eliminate foam in industrial and commercial applications. It works by introducing a non-foaming surfactant into the water or other liquid. This surfactant reduces the surface tension and prevents air bubbles from forming. The defoamer is most often used in manufacturing processes, such as papermaking and wastewater treatment. It can also be used in household products such as dishwashing liquids and laundry detergents.