HALT and HASS Testing - Understanding the Difference

HALT and HASS Testing – Understanding the Difference



When you buy a product, you want it to do what it is supposed to do, be dependable, and have a long lifespan. These are the qualities that create customer satisfaction and ensure product safety. To be sure that products will perform as expected, they are tested during development. Many are tested under extreme environmental conditions. This includes automobiles, aerospace components, and more. There are two types of testing commonly used – HALT and HASS testing. Let’s look at what each type of testing involves and how they differ.

What is HALT Testing?


HALT is an acronym for Highly Accelerated Life Testing. As the name implies, HALT testing subjects products to extreme conditions far beyond what they are intended to withstand in real-world use. The purpose of HALT is to find the product’s limits or weaknesses so that they can be redesigned and improved before the product goes to market.


To perform HALT testing, engineers first identify methods to monitor the product during testing to help identify what might be causing a failure mode. They then apply the HALT process that will push the product past its limits in each of those potential failure modes. HALT is conducted using specialized HALT chambers. These chambers can rapidly change temperature and apply vibration and other stresses to the test product.

What is HASS Testing?


HASS is an acronym for Highly Accelerated Stress Screening. HASS testing is similar to HALT testing in that it subjects products to extreme conditions. However, the purpose of HASS is not to find the product’s limits. Rather, it is conducted on production units to identify any units that might be defective and likely to fail during normal use..


To perform HASS testing, engineers develop a test profile based on actual test results. The stresses are tailored based on the limits discovered during the HALT. Once a profile has been created, a proof of screen is performed to make sure the test levels are not over testing good hardware. HASS is typically conducted using environmental chambers which subject the test product to rapid changes in temperature and humidity as well as exposing it to vibration testing.

HALT testing

What Industries Use HALT?


HALT testing is commonly used in the automotive, aerospace, and electronics industries. It is also used to test other products that must operate reliably under extreme conditions, such as medical devices and high reliability products.


What Industries Use HASS?


HASS testing is commonly conducted on production units of electronic hardware which includes items such as printed circuit boards (PCBs) and other assemblies. It is also used to test other products such as mechanical parts and assemblies.


Benefits of HALT


HALT testing has several benefits. First, HALT can identify the product’s limits. This information can be used to improve the product design. Second, it can identify potential failure modes. This information can be used to redesign the product or develop new test methods to screen for those failure modes. Finally, HALT can save time and money by identifying problems early in the development process.


Benefits of HASS 


HASS testing also has several benefits. First, HASS can identify defective units before they are shipped to customers. This can save money and reduce customer dissatisfaction. Second, it can improve product quality by helping to identify manufacturing defects. Finally, HASS can save time by identifying problems early in the production process.


Quality Testing Services 

Located in Huntington Beach, Quality Testing Services began as a HALT/HASS testing facility. With more than two decades of experience, it has become the industry leader for product testing in Southern California.


While HALT and HASS remain at the core of our services, we have expanded our product testing services to include ESS, Vibration and Shock Testing, Temperature and Humidity Testing, Life Testing, and much more. While we may not be the largest product testing company in the industry, we believe our attentiveness and flexibility set us apart from other companies. We meet with our clients to completely understand their testing needs and develop a relationship with them. If their product needs special equipment for testing that isn’t standard, we will do our best to fabricate the necessary equipment.


Contact us to learn more about our HALT/HASS services or to get a detailed quote.