Seating comfort and its relationship to spinal profile: A pilot study

Abstract Chair comfort is a subjective rating, comprising many factors which can be conceptually modelled. It was postulated that the overall comfort perceived by chair users is a function of the relative discomfort in various regions of the body and that the discomfort perceived in the lumbar region is a function of the spinal curvature. The results of two experiments are reported here. In the first experiment, five typical office chairs were evaluated in a field experiment using five subjects. The evaluation procedure used a general comfort rating scale, a body part discomfort rating scale, and a chair feature evaluation checklist. The results showed the body part discomfort ratings of the back regions to be critical in chair comfort. In the second experiment, three chairs were evaluated employing six subjects. The spinal posture of each subject was measured with a METRECOM ® digitizer while standing and seated in each chair type. The results indicate that the backrest curvature, and the thigh-trunk angle (included angle between the seat pan and the back rest) are critical for the overall chair comfort. The implications for the chair designer are discussed.

[1]  A B Schultz,et al.  Trunk muscle forces during desk work. , 1986, Ergonomics.

[2]  C G Drury,et al.  A methodology for chair evaluation. , 1982, Applied ergonomics.

[3]  A. R. Lind,et al.  Evaluation of amplitude and frequency components of the surface EMG as an index of muscle fatigue. , 1982, Ergonomics.

[4]  J J Congleton,et al.  The Design and Evaluation of the Neutral Posture Chair for Surgeons , 1985, Human factors.

[5]  S. Habsburg,et al.  What Really Connects in Seating Comfort?-Studies of Correlates of Static Seat Comfort , 1977 .

[6]  J C Jones.  Methods and results of seating research. , 1969, Ergonomics.

[7]  E N Corlett,et al.  A technique for assessing postural discomfort. , 1976, Ergonomics.

[8]  H W Oxford.  Anthropometric data for educational chairs. , 1969, Ergonomics.

[9]  A. C. Mandal,et al.  The Seated Man. Theories and Realities , 1982 .

[10]  William S. Marras,et al.  Measurement of Seat Pressure Distributions , 1987 .

[11]  A C Mandal,et al.  The seated man (Homo Sedens) the seated work position. Theory and practice. , 1981, Applied ergonomics.

[12]  J. J. Keegan,et al.  Alterations of the lumbar curve related to posture and seating. , 1953, The Journal of bone and joint surgery. American volume.

[13]  J K Frey,et al.  Comparison of lumbar curves when sitting on the Westnofa Balans Multi-Chair, sitting on a conventional chair, and standing. , 1986, Physical therapy.

[14]  R. Schärer,et al.  An Ergonomic Investigation of Multipurpose Chairs , 1973, Human factors.

[15]  P. Branton.  Behaviour, body mechanics and discomfort. , 1969, Ergonomics.

[16]  L. Richards,et al.  ON THE PSYCHOLOGY OF PASSENGER COMFORT , 1980 .

[17]  E N Corlett,et al.  How does a backrest work? , 1984, Applied ergonomics.

[18]  B. Shackel,et al.  The assessment of chair comfort. , 1969, Ergonomics.

[19]  C G Drury,et al.  Evaluation of a forward-sloping chair. , 1985, Applied ergonomics.

[20]  Douglas Y Cornog,et al.  Annotated Bibliography of Applied Physical Anthropology in Human Engineering , 1958 .

[21]  Sara J. Czaja,et al.  A Field Evaluation of Office Chairs , 1987 .

[22]  R K Lueder,et al.  Seat Comfort: A Review of the Construct in the Office Environment , 1983, Human factors.