Acoustic ceiling tile often contains asbestos. To be safe, always handle acoustic ceiling tile as if it contained asbestos. Older acoustic ceiling tiles are square, and can be either smooth or contain a characteristic pattern of holes.
T-Bar ceiling tiles (also called suspended or drop ceilings) can be identified by the T-bar grid that holds tiles in place. These ceiling tiles are not actually attached to the ceiling, but rest suspended on a lightweight metal grid. These tiles were common in the 1950s, '60s and '70s. They are common in office buildings, schools and homes built during those years.
When remodeling your home, you can choose ceiling tiles made from a variety of materials that are easy to identify visually. Materials include vinyl, tin, aluminum, polyurethane, plaster and wood.