Abstract:
This study aimed to measure efficiency of two different types of seat cushion. The first type was
made from silicone rubber and polyurethane foam. The second type was made from butyl rubber sheet and
polyurethane foam. Both were for reducing vibration among forklift drivers. This quasi-experimental research
applied pretest-posttest one-group design to verify the result of using seat cushions among forklift drivers
examined among a sample group of 28 participants. Research instruments included a general information
survey form, satisfaction survey form and a set of whole body vibration meter. All the information found about
the participants consisted of single, married, age, weight, height, working hours, meditation time, forklift
driving experience, work tenure, age of forklift for 9 participants (32.10 %), 19 persons (67.90 %), 38.03 years
old (± 8.84), 64.21 kilograms (± 9.67), 166 centimeters (± 4.64), 10 hours/day (± 1.86), 1.64 hours/day (± 0.48),
10.82 years (± 8.92) 11.78 years (± 8.84) and 6.35 years (± 1.42) respectively. Regarding to vibration
exposuree, the average accelerations for vibration before using a seat cushion, after using the first type of seat
cushion and after using the second type of seat cushion were 2.42 m/s2 (± 0.37), 2.03 m/s2 (± 0.23) and 1.89
m/s2 (± 0.16) respectively. The, average acceleration for vibration after using the first type of seat cushion was
statistically less than acceleration before using a seat cushion at the significant level of 0.001 and 0.05, and
average acceleration for after using the second type of seat cushion was statistically less than acceleration
before using a seat cushion at the significant level of 0.001 and 0.05. Considering satisfactions after using a seat
cushion among forklift drivers, an overall satisfaction score was found at the moderate level (2.66 ± 0.56), and
on average, and all the information found about the participants consisted of satisfaction towards use of seat
cushion appropriate size not making work obstacles usability including softness for gets a score of
3.10 (± 0.31), 2.53 (± 0.57), 2.92 (± 0.53), 2.42 (± 0.69), and 2.35 (± 0.73) respectively. To minimize all the
defects and improve the study, future studies should consider and emphasize vibration from forklifts with
different levels of lifting capacity or another type of equipment.