The red straps that you can see are to secure the wheelchair or ECV... the long one that you can see draped across the seat on the right is the over shoulder belt for the passenger. However, it only worked in a satisfactory fashion for those in a stationary chair whereas a person on a ECV was basically free standing with no other support other then the single belt. That left a lot of room for falling out of it. I'm not sure if it was state law, federal law or just something that our insurance company dictated, I really don't remember. I do remember hammering the procedure into the heads of new drivers over and over and over. A wheelchair passenger could refuse the belt and assume their own responsibility if injured, but, the ECV passenger was not given the choice.
The area just behind the driver is for the protection of the driver. Some of the wonderful public get enjoyment out of throwing things at the driver to get their attention. In many, cities, the drivers are completely closed in for their protection.