Using a psychophysical approach to identify a user's self selected thermal comfort on a task chair

Abstract It is understood that posture and support affect discomfort and consequently have received widespread attention from researchers. Another factor that could contribute to comfort is the thermal influence due to interaction between the human and the seating surface for which literature is limited. The primary focus of this research was to identify a user's self-selected thermal comfort on a traditional foam-based seat pan while performing a typing/mousing/reading task. A psychophysical approach was applied to evaluate the thermal influence of a task chair with the seat pan temperature as the objective variable. The method of adjustments protocol used two testing sessions with different initial settings. Results of the preliminary study with 10 female participants between 30 and 45 years indicated that the psychophysical methodology is applicable for the purpose. Results also indicate that users' self-selected comfort was achieved when the average temperature of the seat-pan interface was lower than the participant's oral body temperature. Relevance to industry Properties of seat pan materials should be considered by chair designers, which could help alleviate the thermal discomfort experienced by chair users.

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