It's a good question... for some people, A&O x 3 would indicate a completely normal orientation, while for some A&O x 3 means they aren't oriented to event. Sometimes have to rely on context or, ideally, stop and clarify.
You see EMTs/Paramedics use the A&O x 4 the most it is very helpful right after accidents...ie. Do you remember what just happened? A lot of people will remember everything else but will have a temporary loss of memory at the time of accident.