Anthropometry of Wheeled Mobility Project: Final Report

4.3.1 Reference WhMD Users

The original ADAAG included, in its Appendix, only one reference WhMD user – a male in a manual wheelchair, while the ADA-ABA does not have any. Our results demonstrate that the WhMD population is quite diverse in terms of sizes and functional abilities and that there are significant differences between users of different types of WhMDs. Including Reference WhMD Users in the document helps designers and officials understand the basis for many design criteria in standards and also to address design issues that may not appear in the standards at all. Having a set of multiple Reference Users as opposed to one can benefit designers significantly, and our data can be used to develop many different Reference WhMD Users. We recommend that at minimum three be provided, one each for manual wheelchairs, power wheelchairs and scooters. The Reference Users should include plan and elevation drawings and have key dimensions coded with a corresponding table of values for each code showing the 5th, 25th, 50th, 75th and 95th percentile for both men and women. At minimum, the Reference WhMD Users should have data on unoccupied and occupied length and width, total occupied height, eye height and armrest height. They should also have data on accessories and equipment often attached to WhMD.

Three examples illustrate the need for the incorporation of this information in standards:

1. Occupied Height: Information on the occupied height of WhMDs is often needed in design of amusement attractions, playground equipment, museum exhibits and vehicles.

2. Lines of Sight: Currently, the ADA-ABA has requirements for clear sight lines from seating areas reserved for WhMD users. But, there are no anthropometric data provided to evaluate compliance with those requirements. Basic data on eye height is needed in the standard to help designers determine whether lines of sight are adequate.

3. Armrest height: The height of armrests on WhMD is useful for design of work stations, dining areas and other equipment and furnishings that WhMD users approach as close as possible. A Reference WhMD User could provide that information which is currently unavailable.

Tables showing results from the structural measurements of these three dimensions are provided in Appendix 2.