Good Vibrations? Not for Hands

By: Maureen Paraventi

Tools that emit vibrations can cause debilitating effects on workers’ fingers and hands. © cineberg – stock.adobe.com

Jackhammers, chain saws, rivet guns, angle grinders, sanders, impact wrenches and power drills are just some of the tools and equipment that can transmit strong vibrations to the hands of workers and do-it-yourselfers and result in a condition known as hand-arm vibration syndrome (HAVS). While they’re cutting through concrete or grinding metal, these powerful tools are also sending tremors through the nerves and soft tissues of the hands. Employees in the manufacturing, construction, automotive, carpentry, quarrying, agriculture and forestry industries are among who may develop HAVS. In the U.S. alone, approximately 2.5 million workers are exposed to it, despite the fact that many tool manufacturers have incorporated anti-vibration (A/V) designs into their product lineups.

How serious is this condition (which is also known as vibration white finger and Raynaud’s phenomenon of occupational origin)? The consequences can range from fingers that are numb, painful and unnaturally pale to long-range circulatory and neural effects, like loss of dexterity and sensation and chronic pain. Muscles, tendons, nerves and bones may all be affected. HAVS is irreversible; there is no cure for it, just treatment intended to alleviate the pain. Thus, it is important to watch for symptoms and take action to avoid permanent problems. Workers may notice the following in their fingers and hands:

• A “pins and needles” feeling
• A loss of sensation
• Pain at night that is severe enough to awaken them
• Fingers turning white in painful attacks that can last up to 15 minutes

Symptoms can be more severe in cold temperatures or in a worker who smokes.

Workers whose hands are regularly exposed to vibrations, shift after shift, should be made aware of these signs. According to the National Institute for Occupational Safety and Health (NIOSH), HAVS can present serious symptoms after only a year’s exposure. Home hobbyists who use vibration-emitting tools often should also pay attention.

In the workplace, anti-vibration gloves can be used, along with engineering controls and modified work practices, to protect workers from harmful vibrations. This type of hand protection includes special features designed to absorb vibrations, such as air-filled spaces between the glove’s exterior and its palm and extra layers of vibration-dampening materials.

Factors to consider when selecting anti-vibration gloves

• How important is dexterity? Will the user be required to grasp small objects to accomplish tasks?
• Do the tools being used generate high-frequency vibrations? Grinders, sanders and saws call for different models of anti-vibration gloves than pavement breakers, which emit low frequency vibrations.
• Should the gloves have additional features, like impact resistance or cut resistance? Do wearers have to be protected from impact and shock hazards, in addition to vibrations?
• Will the gloves be worn in extreme temperatures and humidity levels – whether indoors or outdoors?
• Do they need to be oil and water-resistant?
• Should they be high visibility?
• Is touchscreen compatibility a priority?

Those, of course, are in addition to the usual concerns that come into play when choosing any kind of personal protective equipment. It should be comfortable to wear, designed with ergonomics in mind and durable enough to justify its cost.

Anti-vibration gloves are available in both natural and synthetic materials – everything from nylon, a nylon/cotton knit, leather, neoprene and even terry cloth, which wicks away sweat. Knitting mesh or a similar fabric on sections like the back of the hand can make the gloves lighter and more “breathable.” Neoprene is able to stand up to harsh sunshine and other environmental elements.

The optimal coating should be based on expected usage and the variables of the work environment, such as temperature. Nitrile palms give gloves a good grip with oily or wet objects or surfaces. Coatings like polyurethane, PVC and latex are also available, and provide different levels of flexibility and insulating properties.

Padding on the palms and knuckle and finger guards may consist of EVA (ethylene-vinyl acetate), a closed-cell copolymer foam with form and impact absorption properties; thermal plastic rubber, chloroprene rubber and memory gel.

There are varying levels and types of padding available in anti-vibration gloves, and deciding on which models are right for specific workers is no easy task. Comfort and dexterity must be balanced with protection. Bulky padding or padding that is too stiff may prove cumbersome and force the wearer to exert more effort while performing tasks. This can contribute to cramping and hand fatigue. Lesser amounts of padding, constructed of more flexible materials, may not effectively tamp down vibrations.

A few other features to be aware of:

• Adjustable elastic cuffs wrist straps and velcro closures will help gloves fit comfortably and securely.
• Leather protects the wearer from abrasive surfaces, sparks and heat. Synthetic, rubber or plastic gloves can provide barriers against grease, oil, biohazards and chemicals.
• A thermal lining will help keep hands warm in cold conditions.
• Anti-vibration gloves with lots of flex points tend to be more comfortable to wear.
• Fingerless gloves are not recommended, nor are they tested for efficacy, since HAVS always begins at the fingertips and moves toward the palm.
• A worker using different tools to perform a variety of tasks may need to use different models of anti-vibration gloves, to get the dexterity level and vibration protection needed for each tool.

Taking steps to reduce the likelihood of HAVS through the use of anti-vibration gloves and other means can keep your workforce healthy and productive, and prevent lost time and, potentially, long-term disability among
employees. WMHS