There is a common misconception amongst many scientists that standard issue, disposable, lab glove gives indefinite protection against all substances encountered during the course of their work. Analysis of glove manufacturers' chemical resistance data shows that this is clearly not the case. Where standard, disposable gloves are in use (Kimberly Clark Purple Nitrile, in most SLS labs) the general rule is to replace them as soon as contamination is suspected. This will ensure that even chemicals with relatively short permeation times do not make contact with the skin. Where toxic and very toxic substances are being handled it is vital to check the glove manufacturers' chemical resistance data and select a glove that affords adequate protection for the specific chemicals in use.
Disposable gloves generally fair less well against organic liquids and for prolonged, direct contact a more specialist glove material may be required. Ansell produce a comprehensive chemical resistance guide for such gloves (Ansell Chemical Resistance Guide, Permeation & Degradation Data, 8 th Edition). The laminate film Barrier™ gloves give the highest possible breakthrough time against several commonly used organic solvents. However , these gloves are relatively easy to cut/puncture and lack a textured gripping surface. The nitrile Sol-Vex® gloves have a shorter breakthrough times but are still given an excellent degradation rating. They also have better cut/puncture resistance and a textured surface to improve grip.
Remember: the most reliable information comes from the glove manufacturer. They are obliged to test their products to ensure conformity with industry standards. The standard governing the resistance of permeation to chemicals is EN374-3.