Service life
（重定向自Operating life）
A product's service life is its expected lifetime, or the acceptable period of use in service. It is the time that any manufactured item can be expected to be 'serviceable' or supported by its manufacturer.
Expected service life consists of business policy, using tools and calculations from maintainability and reliability analysis. Service life is a unique commitment made by the item's manufacturer and is usually specified as a median. Actual service life is the maximal recorded life of a product.