An In Situ Study of the Habits of Users That Affect Office Chair Design and Testing

Abstract

Objective: The purpose of this study was to perform an in situ assessment of office seating habits that influence chair testing and design. Background: Many chair testing parameters were derived decades ago when the average weight of people within the United States was dramatically lower and the office work tasks less computer based. Method: For the study, 51 participants were randomly selected from Brazos Valley, Texas, businesses to participate in 8-hr assessments of office seating habits. Overall results were compared with current chair testing and design assumptions. Data were collected through written survey and through data logging of seat and back contact pressure and duration with the use of the X-SENSOR™ pressure mapping device and software. Additionally, 1 day per participant of caster roll distance was recorded with the use of a caster mounted digital encoder. Participants were grouped by body mass index (BMI) and weight (BMI <35 and weight <102 kg or BMI >35 and weight >102 kg). Results: It was determined that a significant difference did exist between the groups in mean seat time per shift ( p < .001), back cycles per shift ( p < .002), seat cycles per shift ( p < .01), and caster distance rolled per shift ( p < .001). Conclusion: Several key parameters and assumptions of current chair test methods and design specifications may no longer be valid for the upper quartile of weight range of the current U.S. population. Application: The data collected in this study will enable engineers to determine whether revision of design standards for testing office seating for both normal weight and extremely obese workers is indicated.