whenever you work in blue area of lasers of high intensity you HAVE to wear glasses, I am pre-dental and whenever we are doing fillings, you can NEVER look at the blue UV reflection with bare eyes, we always use shields, ANY reflection, even from a white wall is very harmful for your eyes, the only place u could not wear glasses is when you are outside, and if you shine in someones eyes who is 200meters away they will just be temporarily blined as if you flashed a camera in their face, normally after camera flash everything is black because all your sodium is used up, for the people who had blue shined in their eyes would most likely see everything yellow id assume since the blue rods would be sodium deficient for the next 40 seconds or so