Ammann has upgraded the hand guides on its APR Reversible Vibratory Plate Compactors to reduce vibrations that reach the operator.
A new mounting process reduces hand-arm vibration to below 2.5 meters per second squared over the course of an eight-hour day, which is low enough to not require documentation of operator hours in the United Kingdom. The United States government does not regulate hand-arm vibrations on tools, but the National Institute for Occupational Safety and Health (NIOSH) recommends that jobs be redesigned to minimize the use of vibrating hand tools and that powered hand tools be redesigned to minimize vibration or administrative controls be employed to minimize exposure.
The handle mountings are now standard on Ammann APR 5920, APR 4920 and APR 3520 compactors. The mountings will be added to all other APR models in the second half of 2018, the company says.
Ammann says its new compactor handle helps reduce chances of developing hand-arm vibration syndrome (HAVS), also known as vibration white finger and Raynaud’s phenomenon. Excessive exposure to vibration can cause capillaries in the fingers to constrict, leading to tingling, numbness, pain, loss of color in the fingers and weakened grip caused by nerve and blood-vessel damage. Severe cases are irreversible, while mild cases can show improvement if vibration ends.
To prevent HAVS, compactor operators should wear gloves and limit exposure to vibration. It usually takes several years for HAVS to develop. NIOSH says, however, that evidence of advanced stages of HAVS has been found in cases of one year of vibration exposure.
Along with reducing vibrations, Ammann says, the APR plates’ twin-shaft exciter provides smooth changes to and from forward and reverse. The plates can also deliver reliable compaction on grades up to 35 percent, according to Ammann.