NIOSH researchers conducted a study to compare seat designs on underground coal mine haulage vehicles.
The objective of the study was to support prior findings that NIOSH-designed seats, which incorporated
ergonomic design features (e.g., viscoelastic foam padding and low-back support), are improved designs.
Based on measured levels of vehicle jarring/jolting and perceived discomfort, researchers evaluated four
different designs - two in-use and two NIOSH-developed, ergonomic designs. Researchers collected data
using a short questionnaire, a linear, visual analog scale, and accelerometers with a data recorder. Results
showed that vehicle operators favored the NIOSH seats with added adjustability, low-back support, and
improved seat padding over the existing seats. In addition, the measurements indicated all NIOSH seats
performed better than the existing seat, under the no-load (worse of two) conditions, in reducing peak
acceleration, crest factor, and RMS acceleration. The authors summarize the data collected and operator
preferences for seat designs and different foam padding arrangements.