[mattlondon]

No idea about this specific example, but if it is anything like normal bathroom locks, I'd expect that you'd be able to rotate the bench back upwards with some sort of key/screwdriver/lever from the outside.

I'd worry about someone being ill while sat/leaning-on/collapsed on the bench though meaning you cant rotate it. I guess this is an issue for any door where a body could block it being opened? At the least in a changing room cubicle these are usually open at the top so someone could climb over in an emergency.