When you talk with others about addressing the challenges for those with HMD, be sure that you emphasize the social model of disability. This model has led to important shifts in thinking about disability and where responsibility lies for ensuring the full participation of persons with disabilities. The traditional medical model of disability classifies people based on types of deficiency. By contrast, the social model of disability assumes that disability is not inherent to the person but rather is a social disadvantage that results from the interaction between functional limitations and a lack of accommodation in the environment.
The social model focuses on those at greater risk than the general population of experiencing limited social/community participation because of difficulties with certain basic actions. It examines the degree of difficulty in engaging in common activities as well as the frequency with which that difficulty interferes with daily activities. The adoption of the United Nations Convention on the Rights of Persons with Disabilities has made this shift in focus from deficit to participation limitations official.
You will need to keep emphasizing that, for persons with hidden mobility disabilities, the primary barriers are distance to be walked and time standing. So the “social disadvantage” is the discrepancy between comfortable walking distance and the distance the public is expected to walk, as well as the discrepancy between a “brief” time and expectations that people will stand for extended periods of time (e.g., in queues for service, to observe a public event, to participate in an open house format public consultation, etc.).