Today's electronic equipment is getting much smaller than could ever have been imagined even ten years ago and because of consumer demand it has to be much lighter and more portable. This has led to the development and use of materials such as plastics for use in electronics that must be able to withstand some very harsh environments especially for those products designed for the aerospace and military markets. Both of these end users subject their equipment to very harsh environments and without the use of the HAST test the manufacturer could not guarantee a products lifespan. The HAST test is used to simulate the many environments a product may encounter during its normal life span under controlled conditions. These tests include extremes in temperature that are rapidly cycled between heat and cold, varying levels of vibration that are also rapidly cycled and powering the equipment on and off rapidly while it is undergoing the tests. All of the information that is gathered is then sent back to the developer for analysis. Once the developer has the data from the HAST test he can then look at where the product failed to perform as expected and make the necessary changes in design.

The test is not meant to test the product for longevity like the HALT test, instead it is meant to test the product under extreme conditions to find any weaknesses or flaws in the design before the product is approved for manufacture and subsequent delivery to the customer. To perform the HAST test, a special test chamber is used that allows the product to be placed in a holding fixture where it can be held secure and still powered up. The fixture is designed in such a way that vibration can be applied from a multitude of angles to simulate the bumps and drops a product must be able with stand. The chamber also uses hundreds of kilowatts of power to generate heat and cold with temperatures that can range from -100° F to 390°F in rapid cycles while varying the level of humidity from 0% to 100%. Some HAST chambers can also be used to simulate the changes in atmospheric pressure associated with changes in altitude such as those that might be experienced by aircraft or spacecraft. Much of the electronics equipment that is subjected to HAST test is destined for use in the military market and as such must not fail under less than optimal conditions.

While these tests are used in a wide variety of manufacturing environments they were originally developed for manufacturers of equipment that was being made for military use. You can of course send your products to an independent test facility as long as your company has the time to wait for the results and the money to hire and outside testing facility. The other choice you have is to someone like Reliability Help come in and train your staff how to perform a HAST test as well as the other testing methods. Investing in a HAST test chamber can save your company in the long run as you develop higher quality products in less time.