Design Considerations for Variable Washbasin Considering wheelchair Users in Public Disabled Toilets

Background Since the washbasin installed in the toilet for the disabled is fixed, it is inconvenient for a wheelchair user as well as a short or tall person to use. Therefore, this study was conducted with the purpose of suggesting design considerations that can be referred to when developing a variable washbasin in consideration of wheelchair users who use public disabled toilets. Methods First, previous studies on washbasins considering domestic and foreign wheelchair users and cases of washbasins with variables applied were investigated and analyzed. Second, factors to be considered for variable washbasin design were derived, and a design proposal that was variable vertically and horizontally was presented. Third, a prototype was produced based on the design proposal and design considerations were verified through usability evaluation. Results By adjusting the sink vertically, the space for the wheelchair user's knees is secured, and by adjusting it horizontally, the wheelchair user can use the sink while sitting on the toilet. A vertical variable range of 650 to 750 mm from the floor was required for frontal access to the sink for users of manual and electric wheelchairs, and a variable range setting was required based on the 750 mm distance between the sink and toilet for horizontal variation to the toilet seat. Conclusions The design considerations for the variable washbasin not only contribute to improving the access and usability of the washbasin for users of manual and powered wheelchairs, but also can be applied to research and development of various adjustable devices for the elderly and the disabled in the future.