This test is designed to determine the ability of a material to reduce or eliminate undesirable foam that can be generated during the mixing and application of agricultural chemicals in dilute aqueous mixtures.

This method is useful for testing liquid defoaming agents, such as "silicone emulsion" or "organic" type defoaming agents. In principle, it might also be used to test dry antifoam agents with minor modifications to the procedure.

This method could be employed to determine the relative effectiveness of one defoaming agent versus another. It is left to the user of this method to interpret the results with respect to the actual field use of the defoaming agents tested.

This method assumes that the defoaming agent being tested has sufficient durability to maintain its activity for the duration of the test.

Sodium lauryl ether sulfate as the foaming agent is described in Section 7, Reagents. If desired the user of this test method may select an alternative suitable foaming agent.