There is a smoking room at the Departure area of the NAIA inside the coffee shop. There is no smokling at the Arrival area, however. It is strictly prohibited and no exits within the Immigration and Customs, but as soon as you exit, which is 30meters away you can smoke everywhere. You can go out for awhile while waiting for your luggage, though, and go back in. Bring your ticket and passport. At the Centennial Airport PAL departure and arrival areas, no smoking at all. Only at the exits. You can go in and out though, 10meters away.