Relationship of demographic variables on perception of fatigue and discomfort following prolonged standing under various flooring conditions.

It has been suggested that prolonged standing is associated with pain and discomfort experienced by assembly line workers and other occupations. In an attempt to alleviate these problems, companies have implemented ergonomic interventions which include alterations to the flooring conditions upon which workers stand. The purpose of this study was to investigate assembly line workers' perceptions of fatigue and discomfort associated with various body regions after standing for an 8-h shift on three different flooring conditions: (1) standing on a wood-block floor, (2) standing on a floor mat, and (3) wearing insoles. Eleven assembly line workers employed at a large Midwest manufacturing company participated in the study. They were exposed to one of three flooring conditions each Monday for 3 weeks during their 8-h work shift. A Latin Square research design was used to schedule participant rotation. Following their shift, participants answered a questionnaire inquiring about perceived firmness of the flooring condition, and perceived fatigue discomfort. Overall, this study found that the insoles and mat conditions appeared to decrease general fatigue, leg fatigue, and discomfort ratings. Moderately strong correlations were found for the variables of age, height, weight, and job tenure. Older participants and participants with more seniority experienced less discomfort while wearing insoles. Shorter subjects indicated higher scores of perceived firmness while standing on the wood-block floor and mat. No statistically significant differences were found between flooring condition and subjective ratings of fatigue or discomfort in various body regions. However, the insoles and mat conditions were perceived significantly softer than the wood-block floor condition. Insoles and mat conditions were also chosen significantly more often as conditions participants would use after the study when compared to the wood-block floor condition.