Even with robotics and automation handling more and more of the industrial jobs that once required workers to manually submerge parts in hazardous chemicals, the risk of hand injury from chemicals remains a major threat. Chemicals retain their potentially hazardous characteristics, whether exposure comes from outright submersion or an incidental splash.
Unfortunately, the more machines take over the dirty work, the more safe from risk workers feel. This can lead to a more casual attitude toward glove wearing or wearing a glove past its protective life span. However, any skin contact – whether from a splash or from residual chemicals – can result in chemical burns and that potential for injury remains in almost every work environment where chemicals are used. In addition, many jobs require that workers pour chemicals into containers, apply chemicals manually, mix chemicals or transport chemicals and deal with accidental leakage on a daily basis.
It's likely that most safety managers wish there was a single glove that could cover all the chemical contingencies. Unfortunately, there is not. The situation is compounded by the fact that one worker may face risk from several different chemicals, each of which requires a different glove material for maximum protection.
General guidelines, such as the following, outline the suitability of the most common chemical-resistant glove materials for protection in various situations:
Butyl: High permeation resistance to gases and water vapors as well as highly corrosive acids, Ketones and esters.
Natural rubber latex: Resistant against animal fats, caustics, acids, salts, alcohols and detergents.
Neoprene: Durable resistance against a wide range of chemicals as well as solvents and oils, especially acids, caustics and greases.
Nitrile: Durable resistance against a wide range of chemicals including oils, especially petrochemicals, fuels and most acids.
PVC: Durable resistance and barrier protection against some chemicals, especially petrochemicals, oils and grease.
Viton: Highest chemical resistance to aromatic hydrocarbons such as benzene, toluene and xylene.
Making the Right Choice
Employers are challenged to determine which chemical-resistant gloves will provide the best protection and to then educate workers about when to wear the different types of gloves. Employers also need to educate employees on how to care for their chemical-resistant gloves and to recognize signs that the glove needs to be replaced.
The importance of making the right choice of glove material is apparent when samples of the glove material are immersed in the subject chemical. In one instance, we submerged 2-inch squares of natural rubber latex (NRL), nitrile and neoprene in perchloroethylene (a common dry cleaning chemical) for 2 minutes. The NRL ballooned and elongated, and the neoprene sample came out brittle. In contrast, the nitrite swatch was unaffected and clearly the right material for gloves in this environment.
Employers cannot go around testing glove material swatches in various chemicals. Fortunately, manufacturers test the efficacy of glove materials using American Society for Testing and Materials (ASTM) standard permeation and degradation tests. Gloves are rated for particular chemicals based on those tests.
Help at Hand
Knowing that gloves have been tested and finding the right glove are two very different things. Every glove material has its limitations. Thus, it is important for workers to be aware of signs of permeation, penetration, degradation and contamination:
Permeation: Permeation occurs when substances pass through the intact material of the glove at the molecular level. Permeation also is known as the “silent killer."
Penetration: Penetration occurs when a substance passes through a seam or damaged part of the glove, such as a pinhole or tear.
Degradation: Degradation occurs when a substance damages the material of the glove, making it less resistant. The end result is the physical breakdown of the polymer.
Contamination: Contamination occurs when the inside of the glove becomes contaminated throughout the wrist opening and gauntlet, most likely due to poor donning/doffing practices.
If the glove doesn't measure up, it's time to replace it. Often the ongoing effectiveness of a given glove can be determined by simple sensory tests:
- Does the material feel like it did originally or has it become brittle?
- Does the material smell like the chemical it is supposed to be protecting against, even after thorough rinsing or washing?
- Is the exterior of the glove intact?
Hand skin exposure to chemicals is a workplace risk that can be managed or even eliminated with the proper use of chemical-resistant gloves. When proper gloves are not worn, the results can be debilitating chemical burns that take the worker off the job and seriously affect his or her quality of life.
Dave Shutt coordinates Showa Best Glove's new product development in general purpose, disposable and chemical-resistant glove lines among research and development, field sales and marketing teams, as well as distributor and end-user customers. A 20-plus-year veteran of the glove industry, he holds a degree in business administration from Malone College and is a Carnegie graduate. For more info about glove selection, applications and chemicals, visit http://www.chemrest.com.