Are you all right, then?

In the US, "How are you?" is a common greeting.  It's generally understood that this polite salutation isn't really an inquiry after one's health, well-being, or mood.  Probably the most frequent answer would be a variation of "Fine, thanks, and you?"  In many cases it doesn't even elicit a response, such as when two neighbors pass each other in the neighborhood, one walking the dog and one out for a run.  A "Hi, how are you?" as the runner goes past the walker might simply go unanswered, and that would be ok.

If, however, one of those neighbors tripped and fell, the other would rush to the tripper's aid, helping them up and asking, "Are you okay?" or "Are you all right?"  This is a direct solicitation for information on the person's well-being, and the questioner would expect an answer.  "Oh, yeah, I'm fine.  That was silly of me not to see that there and trip over it."  Or, "Please summon medical assistance."

It took me awhile after we moved here to pick up on a subtle difference in speech.  When I was asked by a Brit, "Are you all right?" or "Are you all right, then?" I wondered if there was something about my appearance that made me look not all right.  Did I look so frazzled or anxious that they were concerned for me, and thought perhaps I should sit down?  Did my complexion display a pallor that looked troublesome?  Finally I realized that "Are you all right?" is equivalent to  a US "How are you?" and I could respond appropriately without thinking there was something worrisome about they way I look.