When a worker is handling harsh solvents, pesticides, or industrial cleaning acids, they rely on chemical-resistant gloves to protect their hands. The vast majority of workers look at their gloves and make a fatal assumption: if the glove isn't melting, tearing, or changing color, the chemical isn't getting through. This assumption completely misunderstands how chemicals interact with synthetic polymers.
There are two distinct ways a glove fails: degradation and permeation. Degradation is obvious-it is when the solvent physically melts, hardens, or dissolves the glove material. But permeation is a silent, invisible killer. Permeation is the molecular migration of a chemical through the intact glove material at a microscopic level, without causing any visible damage to the glove.
Many extremely common industrial solvents-like acetone, methyl ethyl ketone (MEK), and certain aromatic hydrocarbons-pass right through standard nitrile and natural rubber gloves like a ghost through a wall. The solvent molecules wiggle between the polymer chains of the nitrile, travel through the thickness of the glove, and emerge on the inside, directly against the worker's skin. The glove looks perfectly pristine, but the worker's skin is absorbing a highly toxic dose of chemicals.
Workers often notice this phenomenon and misdiagnose it. They will take off a glove after handling MEK and notice their hand is sweating profusely, or the inside of the glove feels slick and wet. They assume their hand is just hot and sweating. In reality, that "sweat" is the solvent that has permeated the glove. By the time they feel the wetness, the chemical has been sitting on their skin for an extended period, being absorbed directly into their bloodstream.
You cannot choose a chemical glove based on how thick it is or how tough it looks. You must consult the manufacturer's chemical compatibility chart, specifically looking for the "breakthrough time" for the exact chemical you are using. A heavy, 15-mil nitrile glove might have a breakthrough time of only 4 minutes against MEK. For that specific chemical, you must switch to a completely different polymer, like a laminated polyethylene or a butyl rubber glove, which blocks the permeation. If your hands feel unusually wet or cold inside your chemical gloves, do not assume it is sweat. Wash your hands immediately, throw the gloves away, and find the right polymer for the job.
