He's right, it depends on the host of the event to deter confusion. But for the most part, what will determine the host from banning the mask will be the % of what we call "Caution Color" on the mask. My mask has yellow on just the mouth, it's black up the face and around the lens. I ref with it, and I play with it, I do dirty things with it(like hitting snake)
but seriously I've seen VERY yellow/orange masks in psp or nppl or ncpa tourneys. Most of the refs distinguish their status by their jersey anyways. So You shouldn't worry about the mask that much.