This may seem like a very odd question, however I remember seeing this talked about explicitly. Is there any prohibition of urinating in front of another person? Say for example you are the bathroom taking a showering and someone (of the same gender) has to urinate very badly. Is there any problem of doing it while the person is there in the bathroom and might see (obviously they could look away.)
Again, I realize it's an odd question but I remember see explicitly that it's a problem to urinate (or defecate as well of course -- perhaps even worse) if someone else is in the same bathroom together or is able to see you. Obviously one could then ask if there is a problem to use a restroom for men where there are urinals.