Chemical resistant gloves are made from polymers, some are rubbers and elastomers while others are plastics. These polymers provide a barrier between the hand and the chemical a user is exposed to but the resistance each polymer offers is dependant on a number of factors;
There are standards in place to assess some of these attributes
EN 374-2; this tests for any defects in the glove such as holes and seams using two different methods. The water leak test requires the glove to be filled with water and any leaks observed are recorded while the air inflation test inflates the glove under pressure, underwater where any leaks will show as air bubbles.
EN 16523-1 (formerly EN374-3); this tests for permeation of chemicals through the polymer representing totally immersion in the chemical. As this effect is not visible with the naked eye, specialist test equipment is used to detect when the chemical permeates through to the inside of the glove.
EN374-4; this tests for loss of strength in the glove when exposed to a chemical. In reality, degradation is what a user will experience as the glove “failing” during use and manifests itself as swelling, weakening or hardening of the article
It is true to say that no polymer protects against every chemical as some have better resistance to certain categories of chemical than others.
Every chemical resistant glove must display a pictogram on the packaging. Depending which standard is used, it may be either of the two shown below. The three letters refer to the three chemicals (from a list of standard defined chemicals) for which a breakthrough time of at least 30 minutes (level 2) has been achieved.
A B C