Chemical resistant gloves are a type of Personal Protective Equipment (PPE) designed to form a barrier between the skin and hazardous substances. Manufactured from various synthetic polymers or rubber compounds, these gloves prevent chemical contact that can cause burns, dermatitis, or systemic health issues through skin absorption. Selecting the correct glove material is paramount, as protection is highly specific to the chemical being handled; no single glove offers universal defense. The effectiveness of this protection relies entirely on understanding how a specific chemical interacts with the glove material.
Categorizing Protection by Chemical Class
Chemical resistant gloves are rated against broad categories of substances, each posing a distinct threat to the glove material itself. Corrosives, which include strong acids and bases, such as concentrated sulfuric acid or sodium hydroxide, require thicker, non-reactive polymers that resist chemical attack and physical breakdown.
Organic solvents are often the most challenging category, as they rapidly dissolve or soften many common glove materials. This group includes chemicals like toluene, acetone, and benzene, which can pass through a glove quickly if the material is incompatible.
Alcohols and esters, such as methanol or ethyl acetate, represent a third class commonly encountered in laboratory and industrial settings. These substances still require specific material selection to prevent permeation. The European standard EN 374 classifies gloves as Type A, B, or C, based on the number of test chemicals they resist for a minimum of 30 minutes, with Type A offering the highest level of proven resistance against at least six chemicals.
Understanding the Limits of Resistance
The term “chemical resistant” does not mean “chemical proof forever,” and understanding how a glove fails is crucial for safe use.
Permeation
The most common failure mechanism is permeation, where a chemical moves through the glove material at a molecular level, even if the glove appears physically intact. Permeation involves the chemical first being adsorbed onto the outer surface, diffusing through the polymer structure, and then desorbing from the inner surface. The time it takes for a chemical to be detected on the inside is called the breakthrough time. This measurement is a fundamental safety metric, and the glove must be replaced before this time elapses.
Degradation
A second failure mode is degradation, which is the physical breakdown of the glove material upon contact with a chemical. Degradation can manifest as cracking, swelling, stiffening, or loss of tensile strength, compromising the glove’s structural integrity.
Penetration
The third mechanism of failure is penetration, which occurs when a chemical flows through macroscopic imperfections in the glove, such as pinholes, cuts, or flaws along seams. While permeation is a molecular process, penetration is a bulk flow of the liquid chemical, often due to manufacturing defects or physical damage during use.
Matching Glove Materials to Specific Hazards
The performance of a chemical resistant glove is directly tied to the polymer material used in its construction. Because the chemical interaction is so specific, users must consult a manufacturer’s chemical resistance charts, often called permeation guides, before selecting a glove for a specific task. These charts provide tested breakthrough times and degradation ratings for various chemicals, which is far more reliable than relying on general material compatibility alone. Choosing the wrong material, such as using latex with acetone, can result in immediate failure and chemical exposure.
Common glove materials include:
- Nitrile gloves, made from a synthetic copolymer, offer good resistance to oils, greases, petroleum solvents, acids, and bases. They are not recommended for use with strong organic solvents or highly oxidizing agents.
- Butyl rubber provides superior protection against gases, water vapors, and highly polar substances like ketones and esters, including acetone. It performs poorly against hydrocarbons and halogenated solvents.
- Viton, a high-performance fluoroelastomer, is reserved for aggressive exposure and offers excellent resistance to aromatic and chlorinated solvents.
- Neoprene offers a versatile, all-around defense against a moderate range of chemicals, including many acids, bases, alcohols, and organic acids.
- Polyvinyl Chloride (PVC) gloves are suitable for protection against aqueous solutions, detergents, mild chemicals, and some petroleum hydrocarbons, but they are not effective against many organic solvents.
Secondary Protective Functions
While the primary function of these gloves is chemical protection, they often provide secondary defensive capabilities, reinforcing their role as comprehensive hand PPE.
Biological Agents
Many chemical resistant gloves meet standards for protection against biological agents, including viruses and bacteria. The EN 374 standard includes testing for resistance to microorganisms and, in some cases, viruses, which is crucial in healthcare and laboratory settings.
Physical Hazards
Chemical gloves also provide a degree of protection against physical hazards encountered during material handling. Depending on the thickness and material, they can offer limited resistance to cuts, abrasions, and punctures. This defense is secondary to the chemical barrier, and for tasks involving significant mechanical risk, a glove with specific cut or abrasion ratings should be prioritized.
Thermal Hazards
Protection against thermal hazards is another secondary benefit. Chemical gloves provide a brief barrier against accidental contact with hot surfaces or very cold liquids, though specialized thermal gloves are more appropriate for direct heat or cold contact.