Ceiling by the damage from smoke from candles or a fireplace. Many historic buildings have celebrated ceilings. Perhaps the most famous is the Sistine Chapel ceiling by Michelangelo. Ceiling height may have psychological impacts. The most common ceiling that contributes to fire-resistance ratings in commercial and residential construction is the dropped ceiling. In the case of a dropped ceiling, the rating is achieved by the entire system, which is both the structure above, from which the ceilings is suspended, which could be a concrete floor or a timber floor, as well as the suspension mechanism and, finally the lowest membrane or
Restoration of the Sistine Chapel frescoes have been predicted by previous restorers. One of the major dangers to the frescoes is automotive exhaust, and they are also vulnerable to the effects of the crowds of tourists that pass through the chapel every day, bringing with them heat, humidity, dust and bacteria (the latter of which can biodegrade paints and pigments). The clean plaster surfaces are more in danger from these destructive elements than they were when they were covered with a layer of smoky wax. Previously, the Sistine Chapel's only ventilation was from its windows in the upper level of the walls. To prevent exhaust fumes