Section 716 addresses fire-rated doors, windows, and other protective devices in fire-rated assemblies. Fire-rated doors must be listed and labeled for the specific application, with ratings of 20 minutes, 45 minutes, 60 minutes, 90 minutes, or 120 minutes depending on the barrier being protected. A 1-hour barrier requires a 60-minute rated door. A 2-hour barrier requires a 90-minute rated door. A 3-hour barrier requires a 120-minute rated door. Self-closing or automatic-closing mechanisms are required to keep doors closed. Closers must be adjusted so doors fully close within 10-15 seconds. Seamless door seals (gaskets) prevent smoke leakage. Fire-rated windows are used in certain applications, with ratings up to 120 minutes. Fire-rated glazing is much more expensive than standard glazing and is used only where required. Fire dampers are automatic closing devices in ductwork that closes when temperatures exceed 160-200 degrees Fahrenheit or upon smoke detection. Dampers must be accessible for inspection and maintenance.