In the natural environment, atmospheric pressure decreases as altitude increases. When automotive electronics, aviation products, batteries and various components are stored or used at high altitude or in flight, they may be affected by the combined influence of external temperature and air pressure, causing changes in physical properties such as material expansion or rupture, or leakage of gas or liquid from sealed cavities, and thus product failure.

A low air pressure test is a test method that uses equipment to simulate a high-altitude low-pressure environment and rapidly verify a product's adaptability to storage, transport and use under low pressure. Low air pressure testing can reveal design defects at an early stage and reduce the failure rate of products in actual use.

Correspondence between air pressure and altitude

In the natural environment, air pressure tends to decrease as altitude increases. However, affected by factors such as standard sea-level pressure, average molecular weight and gravitational acceleration, the correspondence between pressure and altitude is not exactly the same everywhere. The approximate trend is shown in the table below (for reference):

NTEK capabilities

To better serve customers, the NTEK automotive division has introduced a combined pressure-temperature-humidity test chamber with the following capabilities:

Temperature range: -70 degrees C to 180 degrees C

Humidity range: 10% to 98% RH (controllable humidity from 10 degrees C to 90 degrees C)

Pressure range: 0.5 kPa to 100 kPa (5 mbar to 1 bar)

Other capabilities: one 50 mm diameter powered feedthrough for powering and monitoring the sample

Applicable standards

GJB 150.2A-2009, Procedure I - Storage/air transport, Procedure II - Operation/externally mounted flight;

GJB 360B-2009, Test methods for electronic and electrical components, Method 105 Low air pressure test

GJB 548B-2005, Test methods and procedures for microelectronic devices, Method 1001 Low air pressure (high altitude operation)

GB/T 2423.21-2008, Environmental testing for electric and electronic products - Part 2: Test methods - Test M: Low air pressure

GB/T 2423.25-2008, Environmental testing for electric and electronic products - Part 2: Test methods - Test Z/AM: Combined cold/low air pressure tests

GB/T 2423.26-2008, Environmental testing for electric and electronic products - Part 2: Test methods - Test Z/BM: Combined dry heat/low air pressure tests

GB/T 4857.13-2005, Packaging - Transport packages - Basic tests - Part 13: Low air pressure test method