Solution Summary: Vibration Dampening Jackhammer
The vibration dampening jackhammer is an engineering control that may help reduce hand-arm vibration. Vibration dampening jackhammers use a combination of counterbalances, shock absorbers, and/or decoupling internal parts from the outside casting to significantly reduce vibration during use.
Vibration dampening jackhammers come in many different makes and models.
The Dewalt D25980K weighs 68.3 lbs, has a 15 amp motor, and provides 61 ft-lbs of impact energy (Figure 1).
Figure 1. Dewalt D25980K during operation
The tool uses SHOCKS Active Vibration Control® which acts as a counterbalance mechanism (Figure 2). The Dewalt D25980K also has rubber coated handles making the total vibration measurement of acceleration 4.8 m/s2.
Figure 2. SHOCKS Active Vibration Control®
The Bosch BH2760VC weighs 63.2 lbs, has a 15 amp motor, and provides 49.5 ft-lbs of impact energy (Figure 3). The tool has Active Vibration Control™ which in part uses a longer air cushion in the hammer mechanism.
Figure 3. Bosch BH2760VC
The Hilti TE3000 AVR weighs 65.9 lbs and has 50 ft-lbs of impact energy (Figure 4). The tool has Active Vibration Reduction technology, which uses counterbalances, vibration absorbers, and decoupling of internal parts from the outer casting. The total vibration is 7.0 m/s2.
Figure 4. Hilti TE3000 AVR
The Makita HM1810 weighs 71.3 lbs, has a 15 amp motor, and delivers 46.5 ft-lbs of impact energy (Figure 5.) The tool has Anti-Vibration Technology which uses an internal counterbalance system. The tool has a total vibration of 9 m/s2.
Figure 5. Makita HM1810
Hand-arm vibration can cause musculoskeletal disorders (MSDs) such as muscle strains; tendonitis, which is inflammation of elbow and wrist tendons; or carpal tunnel syndrome, which is compression of a wrist nerve, resulting in finger numbness and loss of hand strength. The vibration dampening jackhammer can help reduce hand-arm vibration through a combination of counterbalances, shock absorbers, and/or decoupling internal parts from the outside casting.
How Risks are Reduced:
A vibration dampening jackhammer minimizes hand-arm vibration because it uses various mechanisms to reduce the vibration transferred to the user.
Hilti states their vibration dampening jackhammer “protects effectively against the effects of long periods of vibration exposure.”
Dewalt states their vibration dampening jackhammer “Reduces vibration felt by the user at the handles. A Perform and Protect feature.”
Makita says their vibration dampening jackhammer “greatly reduces vibration and directs more impact energy to the work surface for increased user comfort and greater productivity”
Safety and health experts believe the vibration dampening jackhammer will help to reduce hand-arm vibration by using various mechanisms to reduce the vibration transferred to the user. Research shows that hand-arm vibration risk can be reduced through good management and limiting daily exposure (Griffin 2006).
Effects on Productivity:
A vibration dampening jackhammer may increase productivity by allowing the user to work for longer periods of time while still limiting daily vibration exposure.
A calculator to estimate safe daily vibration exposure can be found at: http://www.hse.gov.uk/vibration/hav/vibrationcalc.htm
Proper hearing protection should be worn during use of jackhammers. For more information visit:
Use of vibration dampening gloves can also reduce hand-arm vibration. For more information visit: http://www.cpwrconstructionsolutions.org/pipes_vessels/solution/110/anti-vibration-gloves.html
Dan Anton, PT, PhD, ATC; and Jesse Brouwer, SPT – Eastern Washington University
Hilti TE3000 AVR
To obtain information, visit Hilti or contact 1-800-879-8000
To obtain information, visit Dewalt or contact 1-800-433-9258
To obtain information, visit Makita or contact 1-800-462-5482
To obtain information, visit Bosch or contact 1-877-267-2499