Which term describes when a chemical passes through a material on a molecular level?

Permeation refers to the process by which a chemical substance penetrates through a material on a molecular level. It occurs when molecules of the chemical move through the pores or spaces in the material, despite the presence of barriers. This concept is particularly significant in hazardous materials incidents, where understanding how chemicals can migrate through protective clothing or other barriers is crucial for safety and response planning.

In the context of hazardous materials operations, recognizing permeation is essential for selecting appropriate protective equipment, ensuring that responders are shielded from harmful substances. This process differs from others like absorption, where a material takes in the substance but does not allow it to pass through; diffusion, which describes the movement of molecules from an area of higher concentration to one of lower concentration; and filtration, which involves separating particles from a fluid using a filter. Each of these processes has its own unique characteristics and roles in chemical safety and management.