The ASTM D4041/D4041M-05 (2017) standard provides a method for determining the ejection mode of mechanical pump dispensers. The practice is used to compare different pump dispensers and their ejection modes, taking into account the effects of actuator design and liquid properties. Since the physical properties of the liquid and the actuator design can significantly affect the ejection mode, different liquids in the same actuator or the same liquid in different actuators may produce different ejection effects. This standard helps evaluate and optimize the ejection performance of pump dispensers, ensuring that they meet design requirements. Users should take appropriate safety measures before use and be aware of relevant regulatory restrictions.