Template:Reliability test design

Quite often, there is a desire to design reliability demonstration tests that have few or no failures. These tests are often required to demonstrate customer reliability and confidence requirements. While it is desirable to be able to test a large population of units to failure in order to obtain information on a design's reliability, time and resource constraints sometimes make this impossible. In these cases, a test can be run on a specified number of units for a specified amount of time that will demonstrate that the product has met or exceeded a given reliability at a given confidence level. In order to do so without a large amount of cumulative test time or failure data, it is necessary to make assumptions about the failure distribution of the product. In the final analysis, the actual reliability of the units will, of course, remain unknown, but the reliability engineer will be able to state that certain specifications have been met.