Accelerated life testing (ALT) refers to the application of higher stresses, such as temperature and humidity, to a product so that it fails more quickly than it would during normal use. In Windchill ALT, you use life stress models to extrapolate the test data from a small sample of overstressed products to predict the reliability of the product at normal stress levels. For a new product design, applying environmental stresses above what the product is likely to experience in the field helps you to identify and resolve component weaknesses early in the design process. Thus, ALT provides for obtaining accurate reliability estimates in shorter time frames. For more information, see Windchill ALT.