What is a HAST Chamber – Highly Accelerated Stress Test Chamber

The HAST Chamber is a test chamber that uses extreme humidity to obtain more information in a shorter test time. It is more severe than normal equipment use. HAST is one type of accelerated testing.

Nihal Sinnadurai developed Highly Accelerated Stress Testing (HAST) in 1968. He was working as a Research Engineer at British Telecommunications Research Laboratories. The purpose of HAST is to test the reliability of electronics components in humid environments. It is used for components that encounter humidity during normal operation. The test is sometimes referred to as the Pressure Cooker Test (PCT).

Highly Accelerated Stress Test (HAST) was formulated to decrease the test time needed to get useful results. Engineers need to find a faster way to check if their product meets industry standards because they don't have much time for projects. HAST testing is one solution. It puts the product under extreme conditions - high temperature (105°C), high humidity (about 85%), and high atmospheric pressure (up to 4 atm). By subjecting the product to heat and moisture stresses, HAST testing can uncover hidden defects that could cause it to fail for the user. In testing products for reliability, defining the test conditions is the primary step. A common standard used for HAST is JEDEC JESD22-A110. Test conditions must meet application conditions in order to make testing relevant. HAST Testing has also in turn become a more cost effective alternative.