What is the ruling on a woman removing her hijab for work, and what is she called if she does so?

Unveiling the head and baring the arms are forbidden by scholarly consensus, and no one should be obeyed in such matters, because there is no obedience to a creature in defiance of the Creator. A woman who does this without necessity is displaying herself. As for unveiling the face, there is a difference of opinion, but the preponderant view is the obligation to cover it, especially in mixed workplaces and when there is a fear of temptation.