Blushing is due to high humidity. If he is spraying is low humidity conditions, then the previous post regarding spray volume is correct.This is called blushing. I have the same problem during the summer in Florida. I use spray cans and Mohawk finishing products has a product called no blush it works great. Just spray it on while the finish is wet or dry and it allows the moisture to escape. Moisture is the cause of the whit (blushing).