The rate at which a chemical moves through a protective garment material is called:

• A. Absorption
• B. Adsorption
• C. Permeation
• D. Penetration

Answer: (C)

Permeation is the rate at which a chemical moves through a protective garment material at the molecular level, moving from the outer surface toward the inner side. It describes how fast the chemical can penetrate an intact barrier, and is what PPE performance tests focus on to determine how long a garment can provide protection. This differs from absorption (uptake of chemical into the material itself, not necessarily passing through), adsorption (chemical binding to the surface), and penetration (physical breach through seams or defects). In short, permeation rate tells you how quickly a chemical can diffuse through an undamaged barrier.