Can we explain the exposure variability found in hand-arm vibrations when using angle grinders? A round robin laboratory study.
OBJECTIVE
To quantify variance components of hand-arm vibration exposure from data collected in a laboratory study of four different angle grinders.


METHODS
Four different angle grinders were sent to seven laboratories for grinding tests by three operators at each laboratory. Vibration in both the throttle and support handles was measured. For one grinder, the experimental set-up was repeated and two measurements were collected for that specific grinder.


RESULTS
At least one-third of the estimated variability is attributable to the wheel and less than one-third to the operator. In repeated experiments, between-occasion, operator and wheel factors explained 4, 29 and 17% of the total variability, respectively.


CONCLUSIONS
Since measured vibrations in the support and throttle handles are significantly differed, measurements should be taken at both locations. Factors influencing vibration variability include the presence/absence of an auto balance unit, wheel and operator, but other factors remain to be elucidated.
Liljelind
I
I
Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine, Umeå University, 901 87, Umeå, Sweden. ingrid.liljelind@envmed.umu.se
Wahlström
J
J
Nilsson
L
L
Persson
M
M
Nilsson
T
T
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D012090:Cumulative Trauma Disorders / Q000209:etiology*; D004867:Equipment Design / Q000009:adverse effects*; D006804:Ergonomics; D005260:Female; D006225:Hand / Q000098:blood supply*; D053421:Hand-Arm Vibration Syndrome / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012106:Research; D013548:Sweden; D014732:Vibration / Q000009:adverse effects*; D055815:Young Adult