Fire-resistance is based on the ability for elements within a building to contain a fire or continue to perform its proper functions, despite a fire that may be occurring. The fire-resistance rating is based upon the duration that a passive fire protection system can withstand a standard fire resistance test. This can be based on length of time or other criteria surrounding functionality. Used for walls, floors and ceilings across any building type, fire-resistance-rated materials meet fire and smoke safety and environmental sustainability requirements. The following classifications may be attained when testing in accordance with UL 72: class 125 rating, class 150 rating, and class 350 rating. High ratings ensure that exterior or interior elements, systems or assemblies meet proper code compliance.