This standard specifies methods for determining the static surface tension of liquids, particularly surfactant solutions. The primary measurement principle is the pull-off liquid film method, which calculates surface tension by measuring the maximum force required to detach a platinum ring or plate from the liquid surface. The standard is applicable for evaluating key properties such as wetting and emulsification of various surfactant products. In practical testing, instruments compliant with this standard are typically fully automated surface tension meters. For example, certain models explicitly support this standard and employ the platinum ring method or platinum plate method for precise measurements. In addition to the methods described in this standard, other techniques such as the drop weight method and maximum bubble pressure method are also commonly used in the industry to determine static surface tension.