It seems obvious that a wheelchair user's seat in a vehicle is actually the wheelchair itself. While standard seats in any vehicle offer safety restraint devices for crash protection, there are questions surrounding an equivalent standard of protection for a wheelchair occupant. The challenge is the diversity in wheelchairs - with their variety of sizes, styles, and the wide range of models. This makes it nearly impossible to standardize a safety device suitable for everyone.
Safety restraints appropriate for wheelchairs often come in the form of strap tiedowns. Different impact requirements call for different restraint systems, and though tiedowns are one solution, they can take time to secure and are not always user-friendly.
To standardize wheelchair safety requirements and to achieve the most secure ride possible in a converted vehicle, the ADA (Americans with Disabilities Act) calls for the observation of several regulations.
One specific development by the ADA is a securement standard that is appropriate for use in standard minivans and involves 4 separate straps as well as the standard seatbelt. This method is very secure but is often improperly applied and therefore not always effective.
Of course, restrictions vary when it comes to public transportation - such as on trains and buses. Regulations are added and adjusted, like the requirement that calls for clear signage to indicate wheelchair-appropriate areas for safe and secure positioning.