What method of product control involves one material physically adhering to another?

The correct method of product control that involves one material physically adhering to another is adsorption. This process occurs when molecules of a substance, often a gas or liquid, adhere to the surface of a solid or liquid, forming a thin film. This interaction is important in many hazmat operations because it allows for the removal of harmful substances from the environment.

Absorption, which is a related concept, involves one substance being taken up into the volume of another, while adsorption specifically refers to the surface interaction. Coagulation and precipitation are processes related to the aggregation of particles or the formation of solid phases from solutions, but they do not involve the specific adherence of one material to another's surface in the same way that adsorption does. Understanding these distinctions is critical in hazardous material handling, where controlling and mitigating spills or leaks is essential for safety and environmental protection.