Don't store photos in a garage or anywhere they'll be exposed to gases like nitrogen oxide or sulfur dioxide. If you live where the photos are stored, the pictures are probably safe. Any visible light, not just ultraviolet light, will fade photographs. If you display photographs, don't put them in direct sunlight. If you want to shine lights directly on photos, consult a museum.
Museums often display photographs, and curators use formulas to figure out where to set the lights.
Remember that even museums don't display their valuable photographs forever. They rotate them. They are more concerned with caring and preserving artifacts than displaying them. Watch out for overhead water pipes, sprinkler systems, heating ducts and toilets on the floor above the storage area. Avoid stagnant air, especially in an area with high humidity.