With, very, very few exceptions, characters in the series don't wear eye protection when performing surgery. It is standard practice throughout hospitals in the United States to do so. However, this was a deliberate decision made by the director for theatrical reasons.
House's office is on the fourth floor of the hospital which, according to the directory by the elevator is the top floor. In addition, the elevator call buttons on the fourth floor only have a 'down' button available. However, multiple shots within the elevator show 7 floors.