Hand Arm Vibration Syndrome (HAVS)

Some of the higher HAVS risk occupations includes in the fields of construction, sheet metal work, welding, automotive repair and electrical work. However, even professions in the medical and dental fields carry some risk, due to the prevalence of machinery that produces high frequency vibrations that may not be as profound as a jackhammer unless you have a particularly sadistic dentist but sustained use of such machinery can be debilitating nonetheless. If a job requires the regular use of any machinery that vibrates at all, the potential exists of developing HAVS to some extent or another. It’s estimated that as many as two million or more workers are exposed to some level of workplace vibration of some sort. To those workers, about half can expect to experience some HAVS symptoms. Anti vibration gloves are a special type of gloves or personal protective equipment (PPE) that reduce the effect of harmful vibration the equipment or machine transmission to the hands of the workers. These gloves are made by using additional layers of vibration damper viscoelastic urethane polymer (Sorbothane) materials at the palm and finger areas of the gloves. They can absorb a limited range of frequencies of the vibration that is responsible for white finger syndrome. Companies may perform an audit of their work environments to determine whether vibration equipment poses a risk to worker health and how significant that risk may be. Calculating those risks takes into account the level, or vibration amplitude, of various equipment that may contribute to HAVS. The threshold vibration value is deemed the acceptable risk level workers can be exposed to with the least chance of developing HAVS. Many tool and equipment manufacturers disclose and provide vibration emission safety guidelines with their products, making it easier for businesses to research and calculate their associated risks. There are many factors that influence the measured transmissibility of these anti vibration gloves and the potential that a glove has to provide protection to the wearer. These factors include the effect of different directions and different frequencies of vibration and how they interact, the differences in transmissibility between the palm and the finger, and the variations due to different forces applied to the glove and due to different physical characteristics of the wearers. Anti-vibration gloves can reduce vibration components at very high frequencies, especially when a low hand coupling force is applied. Other ways of controlling vibration exposure, such as eliminating the need for the exposure, using low-vibration machinery and minimizing exposure times are far more likely to be effective and ought first to be adopted.

Many factors such as the vibration spectrum of a power tool, the main direction of the vibration, the transmissibility of the glove in that direction, the physical characteristics of the wearer and the posture and amount of force applied by the wearer to the vibrating surface will all be combined to define a level of transmissibility which is specific to that set of circumstances. The tool vibration spectrum and biodynamic responses themselves are also influenced by the hand forces, vibration direction, operating styles, working materials and individuals. Therefore, the factors influencing the assessment, performance and effectiveness of an anti vibration gloves are interrelated and their interactions may be complex. The large number of influencing factors and their interactions make it very difficult to accurately predict or measure the actual individual performance of a glove.