Highly aggressive life testing ? or HALT, as it is often known ? is a test method aimed at discovering and improving weak links in a product during the design phase.
HALT is a discovery test as opposed to a compliance test. This means the goal is to find problems, doing everything necessary to find and then remove the weaknesses.
In HALT, every stimulus of potential value ? temperature, all-axis vibration, humidity, UV, radiation, etc. ? can be used under accelerated test conditions during the development phase of a product to find the weak links in the design and fabrication processes. Accelerated stresses in combination (e.g. high-temperature ramp rates and all-axis vibration levels together) are necessary to compress or minimize the time to failure.
See the related feature article, "How to Reduce Warranty Costs Attributed to Temperature Sensors."