The only exterior lights on the building we are working on are historic light fixtures at the entrances to the garage. Although the fixtures are 175 watts and are not partially or fully shielded, they are on motion sensors so they only turn on when a vehicle is approaching the entrance to the garage. The building is unoccupied at night so it is unlikely that the lights would even turn on. This seems to meet the intent of the credit but I am not sure how to document it.