EFFECT OF SEATING ON EXPOSURES TO WHOLE-BODY VIBRATION IN VEHICLES

✍ Scribed by G.S. PADDAN; M.J. GRIFFIN

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 262 KB
• Volume: 253
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.2001.4257

✦ Synopsis

The vibration isolation e$ciency of seating has been evaluated in 100 work vehicles in 14 categories (cars, vans, lift trucks, lorries, tractors, buses, dumpers, excavators, helicopters, armoured vehicles, mobile cranes, grass rollers, mowers and milk #oats). Seat isolation e$ciency, expressed by the SEAT value, was determined for all seats (67 conventional seats and 33 suspension seats) from the vertical acceleration measured on the #oors and on the seats of the vehicles.

For most categories of vehicle, the average SEAT value was less than 100%, indicating that the average seat provided some attenuation of vibration. However, there were large variations in SEAT values between vehicles within categories. Two alternative vibration frequency weightings (= @ from BS 6841, 1987; = I from ISO 2631, 1997) yielded SEAT values that di!ered by less than 6%. Overall, the SEAT values determined by two alternative methods (the ratio of r.m.s. values and the ratio of vibration dose values) di!ered by less than 4)5% when using weighting = @ , although larger di!erences may be expected in some situations. The median SEAT value for the suspension seats was 84)6%; the median SEAT value for the conventional seats was 86)9% (based on weighting = @ and the ratio of r.m.s. values).

Predicted SEAT values were obtained assuming that each seat could be interchanged between vehicles without altering its transmissibility. The calculations suggest that 94% of the vehicles investigated might bene"t from changing the current seat to a seat from one of the other vehicles investigated. Although the predictions are based on assumptions that will not always apply, it is concluded that the severity of whole-body vibration exposures in many work environments can be lessened by improvements to seating dynamics.