Human Factors & Ergonomics Program

Heavy load carrying of water, firewood, and sand/stones is a ubiquitous activity for women living in developing countries. Although the intra-abdominal pressure associated with heavy load carrying is hypothesized to increase the risk of pelvic organ prolapse (POP) among women, relevant epidemiologic data are lacking. We conducted a comparative study involving two exploratory cross-sectional studies among convenience samples of women carrying heavy loads, with different characteristics: (1) as part of their activities for daily living, in Shinyanga region, Tanzania; and (2) working as...

Prolonged sitting time is associated with negative health outcomes, including physical discomfort. Chair design affects seat posture, micro-movement, and pressure distribution, which impacts the user experience. This study investigated the impact of mesh versus foam material, on comfort, preference, and subjective performance. Two chairs were used over a three-hour bout of sitting on two different days. Analysis showed no significant difference in pain, comfort, discomfort, or fatigue between chairs, but pain increased in both chairs during the last hour of sitting. The foam chair...

Numerous ear-related wearables require precise measurements of the external acoustic meatus (EAM) to optimise function and comfort. The purpose of this study is to describe a novel methodology for measuring the EAM. A total of 23 measurement variables (18 novel) of the EAM from the entrance to the second bend were collected on 700 Chinese subjects (age: 15-83) using casting and 3D scanning over seven age spans: 10, 20, 30, 40, 50, 60 s and 70+. The ear horizontal plane was identified as a new reference plane for measurements and the medial concha was selected as the reference point...