I keep telling a colleage in wotk that he ought to become a design consultant for the disabled. He has had a lot of experience escorting his wheelchair bound wife.
Problems such as the RADAR key(for the disabled toilets) being kept in the upstairs office, disabled toilets in a new building being upstairs, whether a couple should use the gents or the ladies etc.

He does say the the Royal Albert Hall is the most user freindly concert venue that he has been to though, and he got in free as his wife's carer.