As per company requirement we need to measure the machine tool vibration ( HandArm Vibration (HAV)) from our pneumatic tools like impact wrench, needle gun etc. We recently procured a HAV meter make Bruel & Kjaer. Now they hade given around eight measuring parameter and I am confused which one to use. The different parameters are

Amp-Maximum peak acceleration
Aeq-Equivalent constant acceleration for the entire measure. Period
Amax-The max. RMS acceleration that occurred during the measure. Period.
Amin- The min. RMS acceleration that occurred during the measure. Period.
Aeq4-the four-hour equivalent energy RMS acceleration
Aeq8-the eight-hour equivalent energy RMS acceleration
Peak-The max peak over the last 1s interval
Inst – A randomly sampled instantaneous RMS acc. over the last is interval

The readings obtained on some of the impact wrenches are so high nearly Amp-300 M/S2
Any body have any idea how does the test is to be performed and which parameter is to be used.

All parameters are to be used. You need average, max and min over time - as the example states; each are different and all used together to be applied against the standard.

Thanks for your replay Sam. Can you explain alittile bit more. As per my knowlege the EAV is 2.5 M/s2 for 8 hrs. Now hoe can we comes to this figuers from the eight datas. Or we can just see Aeq8 value.

I see you are in the UAE which may not be the same standard as set forth by the USA or UK or EU, etc... then again, you said specifically - your company's requirement. What numbers have they published? B&K gave you a means by which to obtain data and how, not necessarily stating compliance requirements.

Sam is right that if you apply a spec or standard, the spec or standard dictates the type of measruement.

Harris' "Shock and Vib Handbook", 5th ed, Chapter 42 addresses effect of vib on humans and there is a section on "hand-trasnmitted vibration". In that section they cite standard ISO 5349-1. For that standard, the assessment of vibration exposure is based on the "8-hour energy equivalent vibration total value" which they call a_hv_eq8. The variable that feeds into th 8-hour averaging calculation is a_hv. There is a lot of discussion of where a_hv comes from. It is frequency weighted according to figure 42.26. It has a factor to account for combination of the three directions.

Whether a_hv_eq8 is the same as your Aeq8, I'm not sure.

This was discussed some at Hand-Arm Vibration

A quick Google of "Hand Arm Vibration" turned up a good article on Hand-Arm Vibration

You really need to get the appropriate ISO Standards. There are a number of them, so you will have to research them to see which you need (they are not free).

Any problem that involves "liability" should be thoroughly researched. Quick and easy answers should be avoided, as they can get you (and your company) into serious trouble. Do the research. Do the required work. There are no shortcuts when doing this type work.

I have found this document EU Good Practice Guideto be extremely useful in working through these issues...it's very important to understand how to get a representative exposure sample from all the work performed. Perhaps this new technology (attachement) could help. Also this ppt
HAVS PPT

HAVSense_0708.pdf (902 KB, 27 downloads)

Pretty slick system. Thanks for the link!

Fwdthinker,
thank you for both pdfs. They are very informative and well written.

This is greate and very informetive. Thanks for all.