An ergonomic approach to public squatting-type toilet design

This paper reports a case study on public squatting-type toilet design, which was undertaken with a special emphasis on ergonomic considerations. A field survey on the use of public toilets in Taipei reveals that almost half of the subjects take a non-sitting posture while using the sitting-type public toilets and 86% of the subjects agreed that the squatting-type public toilets better satisfy sanitary requirements. An experiment was conducted to determine relevant anthropometric data for a redesign of squatting-type toilets. One of the variables studied was the effect of the footstep slope on squatting comfort. A total of 80 subjects as tested on four footstep slopes: 0 degrees, 15 degrees, 30 degrees and 45 degrees. Their heart rates were measured before and after the test, and their subjective evaluations of squatting comfort were also recorded. The 15 degrees slope was found to be preferred. These findings were then used in design development where mock-ups were presented to subjects for evaluation, then modifications were made and further tests conducted for verification. The result shows that the ergonomic approach is feasible recommended to be adopted in the process of product design of such facilities.