Public transport could be the only transport means for some people, in particular those with disabilities. Accessibility of public transports is thus essential to enable everyone to participate in the society, for example by accessing to employment, healthcare and leisure activities. Legislative framework and regulations ensure minimum accessibility standards, but are not always enough to ensure effective accessibility. In this paper, the SOLID model of accessibility and its main components are presented. This model has been developed through public consultations and experiments with people with visual impairment, and then refined through experiments with other populations and discussions with public transport companies. Then the paper presents examples of usage of the model for improvements in public transports in and out of the disability context. This illustrates how the model is a useful tool to identify accessibility issues and propose solutions in different domains such as architecture, vehicle design, traveller information or smartphone application. The paper also demonstrates how research on disability is relevant to work on the general human condition.