Hand-arm vibration syndrome is a debilitating condition caused by excessive use of hand-held powered equipment. When managing the risk, the first step is to record details of your equipment on a register.
This could be anything from a small piece of equipment, e. Some of the most vibrating hand-held tools are concrete breakers and jack hammers. This is the measure of how many small movements the tool makes in a second. To find out the vibration emissions, first check on the tool itself, quite often it will have this information on a sticker on the casing.
If not you should be able to locate it in the user manual. If a tool has changeable attachments you should list it several times with each attachment detailed on a separate row. Manufacturers and suppliers should provide data for each one. Manufacturers and suppliers have been required to supply vibration magnitude information with the tool since If you have older tools you may need to contact your supplier for the information.
It may be time to start thinking abo ut updating your tools entirely. Most modern tools have been designed with v ibration in mind and the values, i. More than one row is required when a worker is exposed to vibration from more than one tool or process within the same 8-hour shift. After entering the data the outputs will appear in the light blue areas.
To clear the calculator of all values, click on the Reset button. Calculator Inputs:. Calculator Outputs:.
Job Description — Three different air-powered tools including one impulse nut-runner and two screw drivers are used on this assembly line.
Job rotation is used in this department to reduce exposure to powered tools and expand the job tasks required to lessen HAVS and MSD risk. Actual in-use vibration values were measured with a vibration meter. An estimate the exposure duration for each tool was determined by observation and measurement of a sample period of typical work. In addition, the production rates were obtained from the department supervisor to determine the maximum number of repetitions required in a typical 8-hour shift.
To determine the Total Exposure Points, the vibration magnitude and exposure duration values for each tool obtained in Step 1 and Step 2 are entered into the white fields on the calculator as shown below:.
The total exposure points value of 82 in this example is below the Exposure Action Value EAV of points, indicating that this task does not pose significant risk of HAVS for most healthy employees. Job Description — Five different air-powered tools including impulse nut-runners and screw drivers are used for this assembly process.
The total exposure points value of in this example exceeds the Exposure Limit Value ELV of points, indicating safe limits have been exceeded and employees are at significant risk of developing HAVS. Controls should be implemented immediately to reduce vibration magnitude exposure.
Job Description — A conventional not vibration controlled vertical grinder and a conventional not vibration controlled chipping hammer are used to clean castings as shown above. The declared vibration value is given by the manufacturer as 6. An investigation shows a trigger time per 8-hour shift of 2 hours for the grinder based on a wheel-consumption of 20 wheels per week and an average lifetime of a wheel, when used by this operator, of 30 minutes.
A time study shows that the trigger time for the hammer is 15 minutes per 8-hour shift. To control the risk you have only two possibilities, lower the vibration value or decrease the exposure time.
Time can be reduced by changing to a more efficient process or by introducing job rotation. Modern tools with vibration control often show considerably lower vibration values.
In many cases they are also more efficient and the job will therefore be done faster. Material removal rate for grinders is directly proportional to power.
Therefore, choosing a grinder with the highest possible power will significantly decrease grinding time. The new grinder has a declared vibration value of 3.
The tool is twice as powerful as the old vertical grinder. The trigger time is assumed to be the same 15 minutes because the tools have similar blow energy. So to summarize, the grinder vibration value is decreased from 6. The total exposure points value has been reduced from down to just 87 points.
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