Just about any substance found in the workplace that is not specifically designed for washing, skin care or hygiene can qualify as a chemical. By extension, any glove designed to act as a physical barrier between our hands and the substances we work with qualifies as a chemical-resistant glove.
By Karoly Ban Matei on behalf of Safeopedia
If you never looked into it, you might be surprised by just how broad the definition of "chemical" is.
The Merriam-Webster Dictionary defines it as a "substance made by a chemical process." That definition is so wide-ranging that it encompasses most of the materials we're familiar with.
OSHA doesn't narrow it down much, either. They define chemicals as "any element, chemical compound or a mixture of elements and/or compounds."
What these definitions show is that just about any substance found in the workplace that is not specifically designed for washing, skin care or hygiene can qualify as a chemical. By extension, any glove designed to act as a physical barrier between our hands and the substances we work with qualifies as a chemical-resistant glove.
Due to the wide variety of chemicals and their numerous hazardous properties, chemical resistant gloves come in a number of different styles and are made from carefully selected materials.
In this article, we'll go over the many types of chemical-resistant gloves and how to choose the right ones.
When Should Employees Use Chemical-Resistant Gloves?
The very short answer is: employees should use chemical-resistant gloves any time they handle a chemical that can come in contact with their hands. This includes:
- Changing a toner cartridge
- Working with adhesives
- Washing engine parts
- Cleaning and maintenance
- Performing an oil change
- Decanting substances from a large receptacle into a smaller one
While most people think of chemicals as liquids, it's important to remember that chemical gloves also should be used when dealing with chemicals in other forms. Some chemicals can damage your skin or enter your bloodstream when they're in solid or gas form, so it's important to use proper protection.
Workers who use chemicals that are under pressure and can be injected under the skin should use chemical-resistant gloves that also are puncture-resistant. (For related reading, see Top Tips for Preventing Chemical Spills in the Workplace.)
Standards for Chemical-Resistant Hand Protection
OSHA regulation 29 (CFR) 1910.138 states that employers are responsible to ensure that their employees use hand protection. Section 1910.138 (a), General Requirements, specifically relates to chemical protection gloves, stating that the gloves have to offer protection against skin absorption of harmful substances, punctures and chemical burns.
In 1910.138(b), OSHA provides this guidance regarding the selection criteria for hand protection:
Selection. Employers shall base the selection of the appropriate hand protection on an evaluation of the performance characteristics of the hand protection relative to the task(s) to be performed, conditions present, duration of use and the hazards and potential hazards identified.
This requirement ensures that the choice of chemical protective gloves is based on a proper hazard assessment. The organization has an obligation to assess the job for chemical exposures and then select the chemical protective glove based on its material, thickness, length and other relevant traits.
For guidelines on how to properly choose the proper glove for your application, consult ANSI/ISEA 105-2016, the selection criteria for the American National Standard for Hand Protection. It offers a numeric scale that manufacturers can use to rate their products against certain contaminants and exposures. Understanding this scale can help you make better-informed decisions about which gloves are best suited for your application.
When choosing chemical-resistant gloves, consider the following:
- What materials are being handled
- The concentration of the chemical(s)
- The temperature of the chemical(s) and work environment
- Frequency and duration of contact with the chemical(s)
- Total immersion vs. splash only
- Length to be protected (hand, forearm, arm)
- Dexterity required
- Grip requirements
- Size and comfort
So Many Glove Materials - But Which Is Best?
Figuring out what size and style of glove you need is important, but so is the material the glove is made from. There are many materials to choose from, but not all of them give proper protection against every type of chemical.
To help you select the right gloves for your job, we'll go over the most common chemical-resistant glove materials.
Latex - Latex had been a very widely used material for a long time. Nowadays, it's losing in popularity. Still, it is a versatile material that offers protection against many biological and chemical agents, including:
- Nitric acid
- Hydrochloric acid
- Sulfuric acid
- Phosphoric acid
- Potassium hydroxide
- Sodium hydroxide
- Some weed killers
Latex is light and stretchable, so it fits snugly to the wearer’s hand. Since it is so tight, the interior of the glove usually is covered with a powder that makes them easier to slide on and off. Because latex gloves are so thin and flexible, they allow for greater dexterity and flexibility. They're also an inexpensive option.
One of the big downsides, however, is that many people are allergic to latex. If you have a big enough workforce, odds are good that some of your employees will have allergic reactions after coming into contact with latex. The material also is not very strong; therefore, it is not recommended where there is a potential for punctures and cuts.
Latex gloves commonly are used in:
- Food handling
- Chemical plants
- Janitorial work
Polyvinyl Chloride (PVC) - PVC is another common material used in chemical-resistant gloves. It offers good protection against acids, bases, amines, peroxides and fats. PVC also protects against more generic substances like:
- Ammonium hydroxide
- Benzylic alcohol
- Boric acid
- Diluted sulphuric acid
- Sodium hypochlorite
- Photo developer fixer
- Phosphoric acid
- Household detergents
- Ethylene glycol
- Chromic acid
That's an impressive and varied list, but that doesn't mean PVC is the answer for all your chemical protection needs. For one thing, it does not offer protection against some organic solvents. It also has poor heat-resistance, which makes it unusable in high-heat environments. Most PVC gloves stay flexible even in cold environments. It boasts fairly high puncture resistance and provides a great grip.
PVC gloves are used in industries like:
- Commercial fishing
- Fuel oil
- Mechanic work
Nitrile - At a quick glance, nitrile rubber seems to blend the qualities and benefits of latex and PVC. Nitrile resists solvents, grease, certain acids and bases, and oils. It also is a great choice when working with:
- Benzylic alcohol
- Brake fluid
- Cutting oil
- Household detergents
- Mineral oil
While some workers are allergic to nitrile, it is far less common than latex allergies and generally is a safe choice.
Nitrile gloves also are puncture-resistant. Punctures, moreover, are far easier to spot in a nitrile glove than in most other chemical-resistant materials, which makes visual inspection easier. Nitrile gloves mold to the hand and offer a snug, comfortable fit for extended periods of time.
Butyl - Butyl is a supple and elastic synthetic material. Thin butyl gloves provide excellent dexterity and flexibility.
Butyl gloves offer excellent chemical resistance against:
- Concentrated mineral acids
- Amine derivatives
- Rocket fuels
- Strong bases
Butyl gloves also have good resistance to oxidation, ozone corrosion and abrasion, while providing high flexibility in low temperatures. Because it is a very good barrier against industrial gases and vapors, it is a common choice for military combat clothing, including gloves.
One downside to butyl is cost. These gloves are fairly expensive. Butyl is classed as a special purpose polymer, reserved for applications requiring very high, targeted, chemical protection. Butyl gloves offer poor protection against aliphatic and aromatic hydrocarbons, which limits their applicability in the oil and gas sector.
Neoprene - Neoprene has been developed as an alternative to rubber, especially for its oil-resistant properties. It's used, among other applications, for handling and working with petroleum products, greases, oils and gasoline. Neoprene also offers resistance against:
- Hydraulic fluids
- Organic acids
- Aliphatic solvents
Neoprene gloves offer good pliability, finger dexterity, high density and tear resistance. They generally have chemical- and wear-resistance properties superior to those made of natural rubber and can be used in high-temperature and cold environments alike.
Depending on the glove's features, including its type, length and material, donning them can be a painless process or complicated affair.
Thickness is the biggest factor that affects ease of donning. Thicker gloves are more rigid and have a larger fit, so putting them on presents no challenge. Thin gloves, including disposable ones, have a tight fit that makes them harder to put on.
To solve this problem, some manufacturers sell powdered gloves. Lining the inside of the glove with powder reduces friction to prevent them from sticking, which makes them easier to put on. The powder itself, however, can act as a carrier for latex proteins, which can cause adverse reactions in workers with latex allergies.
To avoid the allergy-related risks, chlorinated, powder-free gloves are relatively easy to put on without additional allergens.
For thicker, reusable gloves, the discomfort created by direct contact with the material can be reduced by including a cotton liner or by wearing a pair of cotton gloves inside the chemical-resistant glove. When wearing an additional pair for comfort, it might be advisable to pick the next size up to account for the extra thickness.
Regardless of the type of glove being used, it is good practice to wash and dry hands before donning them. You should also check to make sure the gloves are dry inside and out before putting them on.
Choosing the Proper Glove Size
All you need to do to make sure you’re getting properly sized gloves is measure the hand of the user. Measure the dominant hand across the palm. If the palm circumference is 9 inches, then you need a size 9 glove. If, however, the hand measures 9 ½ inches, choose the next size up. Take the time to do this; a glove that is too small can significantly contribute to hand fatigue.
If the size of the gloves you are buying is expressed in lettered sizes (XS, S, M, L, XL, XXL), use the measurement in the chart found here. A less common way to determine your glove size is to measure the distance from the bottom of your palm to the tip of your index finger. Then convert that distance to a lettered glove size using the table below.
Even if you choose the proper glove size, they can become uncomfortable after being worn for a while, especially if they're frequently exposed to sweat. It's a good idea to let employees regularly step away from hazardous tasks and remove the gloves for a minute or so. This allows the hand to dry, avoids overheating, and extends the life of the glove.
Once you narrow down your selection, it's a good idea to let the employees try each glove on and give feedback on fit, comfort, and ease of use. After all, they're the ones who will be wearing them day after day.
When Should Chemical-Resistant Gloves Be Replaced?
Thin, surgical-style gloves should only be used once and discarded. They’re designed for greater dexterity, but this comes with a loss of chemical resistance. Because they stretch, the spaces between molecules are larger, making the gloves susceptible to quick permeation by the chemical.
Even thicker gloves have a limited life expectancy. Because decontamination usually is more expensive than replacing the gloves, manufacturers do not recommend decontamination. Instead, look for signs of puncture, permeation, and degradation and replace gloves that are compromised. Certain gloves can be inflated, by mouth or with an inflation device, to locate holes and punctures. Submerging the inflated glove in water can also help, since bubbles coming out through the glove indicates seepage.
Gloves that look fine and pass visual inspection should still be discarded after the manufacturer’s prescribed lifetime. Manufacturers test their gloves, using the ASTM F739 standard, to determine its length of service.
About the Author: Karoly Ban Matei has worked at a senior level (both as an employee and a contractor) for organizations in the construction and manufacturing industries. He has a passion for developing and improving health and safety programs.
(This post was originally published here by Safeopedia, a member of the Intelex Strategic Alliance Program. Republished with permission. Safeopedia aims to create the ultimate resource for the EHS industry. At Safeopedia, they believe that environmental health & safety information should be in the public domain for anyone and everyone who truly wants to learn, share, collaborate and make the world a better – and safer – place. They are committed to providing free environmental health & safety education and information to the industry and the public at large.)