Apparently, nail polish is a problem.

I am a foreman for a plumbing company. Yesterday we had our foreman's meeting, and I was pulled aside afterwards by the vice-president of our company. He took me into his office to tell me that I was not allowed to wear nail polish as it is unprofessional. He's probably going to visit my site today and check if I took it off. Wish me luck, I like my purple nails.