Permeation refers to movement of a chemical through the garment at the molecular level.

• A. Penetrations
• B. Permeation
• C. Diffusion
• D. Absorption

Answer: (B)

Permeation is the overall process by which a chemical moves through a protective garment at the molecular level. It begins when the chemical sorbs onto the outer surface, then diffuses through the fabric, and finally desorbs from the inner surface into the wearer. This describes passage through intact material, not through holes or defects. Penetration would be passage through openings in the garment, which is a different failure mode. Diffusion is a part of permeation—the mechanism by which molecules move through the material—but it alone doesn’t capture the full through-material passage. Absorption is uptake into the material itself without necessarily moving all the way through to the inner surface. So, permeation correctly characterizes movement through the garment at the molecular level.