Penetration is defined as:

• A. Chemicals passing through the seams only
• B. Chemicals passing through the opening in the fabric
• C. Chemicals dissolving within the fabric
• D. Chemicals absorbing into the fabric

Answer: (B)

Penetration occurs when a chemical moves through an opening or flaw in protective fabric, such as a seam, tear, pinhole, or gap, from the outside to the inside. It doesn’t require the chemical to dissolve into or soak into the fabric; the key is that there is a path created by a hole or opening. That’s why the description focusing on chemicals passing through an opening in the fabric best captures the actual mechanism. If a seam or small defect provides a channel for the substance to get through, that’s penetration. By contrast, dissolving into the fabric or being absorbed into its surface describe other processes (permeation and absorption) that involve the material itself rather than a discrete opening.