Formerly under the jurisdiction of Committee E35 on Pesticides, Antimicrobials, and Alternative Control Agents, this test method was withdrawn in January 2024 in accordance with section 10.6.3 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.

5.1 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.

5.2 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.

5.3 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.

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

5.5 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.

1.1 This test method describes a qualitative method for the evaluation of liquid defoaming agents used to control undesirable foam in dilute, aqueous surfactant solutions. This laboratory test method may be applied to aqueous systems containing additional components, such as agricultural chemicals. This method is described using SI units

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This standard method does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.