The present study aimed at characterising the profile of exposure to hand-arm vibration by jackhammers operators in the construction sector. Vibration levels were evaluated during real work tasks, involving demolitions and pavement breaking. Measurements were made according to ISO 5349:2001 standard. Symptoms were found in only 20% of the workers. Lower ahw (rms) values were found in electric jackhammers, although with relevant differences for equipments with different weight category, when compared with pneumatic powered tools. Differences between the working surface materials (concrete, stone and masonry) were also found.
A jackhammer operates by driving an hammer up and down. The hammer is first driven down to strike the back of the and then back up to return the hammer to the original position to repeat the cycle. The bit usually recovers from the stroke by means of a . The effectiveness of the jackhammer is dependent on how much force is applied to the tool.
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Agency : CCC
Description : Thousands of jack hammer operators are being trained in the CCC by work on truck trail construction. Some 113,000 miles of such roads have been constructed to extend forest fire protection and administration of forest areas.
Other jackhammers are operated so, instead of using compressed air, they'repowered by a continuous stream of hydraulic fluid (perhaps oil or water with additives). This flows through a hydraulic motor or turbine, powering a crankshaft and piston that hammers the drill bit. Hydraulic jackhammers are often used for underground mining where pneumatic tools are less suitable. Sometimes the hydraulic fluid that powers the drill is also used as a "cutting fluid" (for cooling and lubrication).
Our OHIP project for summer 2010 was a collaborative effort between the California Department of Public Health and the UC Ergonomics Program. The main focus of our project was to evaluate the usability of the Jackhammer Lift Assist device. It is well understood that pavement breaking (jackhammering) for extended periods of time increases shoulder and/or lower back injuries (musculoskeletal disorders). Additionally, it is known that when the jackhammer becomes stuck in the ground (a common occurrence), further stress is placed on the lower back and shoulders of the jackhammer operator.