What Is IEC 60068-2-39?
IEC 60068-2-39 is a part of the IEC 60068 environmental testing standard series that specifies test methods for evaluating the effects of combined environmental stresses on electrical and electronic products. Unlike individual temperature or humidity tests, IEC 60068-2-39 focuses on conditions where low air pressure is combined with temperature and humidity factors to simulate challenging operating environments.
This test method is commonly used to verify whether components, equipment, and systems can maintain functional performance when exposed to reduced atmospheric pressure conditions similar to high-altitude environments. By applying controlled low-pressure conditions together with thermal and moisture stresses, engineers can identify potential failures related to insulation performance, sealing capability, material changes, and electronic reliability.
IEC 60068-2-39 testing is particularly relevant for products designed for aerospace, aviation electronics, defense systems, transportation equipment, and other applications where environmental reliability is critical. The standard provides a structured approach for assessing product durability and ensuring that equipment can operate safely under combined environmental stresses.
IEC 60068-2-39 Test Requirements
IEC 60068-2-39 testing requires products to be evaluated under combined environmental stresses where reduced air pressure is applied together with temperature and humidity conditions. The purpose of this test is to determine whether equipment can maintain its performance and reliability when exposed to high-altitude environments or low-pressure operating conditions.
Compared with standard altitude testing that mainly focuses on pressure reduction, IEC 60068-2-39 emphasizes the combined effects of multiple environmental factors. The test conditions are selected according to the product application, operating environment, and required reliability level.
Key Test Parameters of IEC 60068-2-39
| Test Parameter | Description |
|---|---|
| Low Air Pressure | Simulates reduced atmospheric pressure conditions experienced at high altitudes |
| Temperature Condition | Applies cold or high-temperature environments combined with low pressure |
| Humidity Condition | Evaluates product performance under moisture-related stress when required |
| Pressure Control | Requires stable and accurate adjustment of chamber pressure |
| Exposure Duration | Maintains specified environmental conditions for a defined testing period |
| Recovery Condition | Allows the specimen to return to normal atmospheric conditions before evaluation |
Low Air Pressure Simulation Requirements
A critical requirement of IEC 60068-2-39 is the ability to accurately control and maintain reduced air pressure inside the test chamber. This allows engineers to simulate altitude conditions that may affect product performance, electrical insulation, mechanical structures, and sealing properties.
During testing, the chamber must provide:
Stable pressure reduction and maintenance
Uniform environmental conditions around the test specimen
Reliable monitoring of pressure changes
Controlled recovery after low-pressure exposure
Accurate pressure control is essential because rapid or unstable pressure changes may influence test results and reduce repeatability.
Temperature and Humidity Combination Requirements
IEC 60068-2-39 is designed for combined environmental testing rather than isolated pressure testing. Depending on the test procedure, low air pressure may be combined with temperature or humidity stresses to reproduce real operating conditions.
Typical combined conditions include:
Low pressure + low temperature
Low pressure + high temperature
Low pressure + humidity exposure
These combined stresses help identify potential issues such as:
Insulation degradation
Material expansion or contraction
Seal leakage
Electronic component instability
Reduced equipment reliability
Test Chamber Performance Requirements
To perform IEC 60068-2-39 testing effectively, the environmental test chamber should provide:
Precise Pressure Control
The chamber should maintain stable low-pressure conditions throughout the test cycle.
Temperature Uniformity
The system should ensure consistent temperature distribution around the test specimen.
Humidity Management
When humidity testing is required, the chamber should provide accurate moisture control.
Data Monitoring and Recording
Test parameters should be continuously monitored and recorded for reliability verification and test traceability.
Products Commonly Tested According to IEC 60068-2-39
IEC 60068-2-39 testing is commonly applied to products that may operate in high-altitude or low-pressure environments, including:
Aerospace electronic equipment
Avionics systems
Military electronic components
Automotive electronic modules
Communication equipment
Semiconductor devices
Industrial control systems
These products require verification to ensure reliable operation when exposed to combined environmental stresses.
IEC 60068-2-39 Test Procedure
IEC 60068-2-39 testing follows a controlled environmental simulation process to evaluate product performance under combined low air pressure, temperature, and humidity conditions. The typical test procedure includes the following six steps:
1. Test Specimen Preparation
Before testing, the specimen is prepared according to the product requirements and relevant IEC 60068 test conditions. Engineers verify the condition, installation method, and measurement points to ensure accurate test results.
2. Initial Measurements
Initial electrical, mechanical, and functional measurements are performed before environmental exposure. These baseline results are used to compare product performance before and after the IEC 60068-2-39 test.
3. Temperature and Humidity Stabilization
The test chamber adjusts temperature and humidity conditions according to the specified test severity. The specimen is stabilized until the required environmental conditions are reached before applying low air pressure.
4. Low Air Pressure Application
The chamber gradually reduces air pressure to simulate high-altitude environments. During this stage, the specimen is exposed to controlled low-pressure conditions combined with temperature or humidity stresses defined by the test requirement.
5. Environmental Exposure and Monitoring
The specimen remains under the specified low-pressure environmental conditions for a defined duration. Engineers monitor key parameters, including temperature stability, pressure level, and product operating performance.
6. Recovery and Final Evaluation
After completing the exposure cycle, the chamber returns to normal atmospheric conditions. The specimen is inspected and compared with initial measurements to identify any failures, performance degradation, or environmental damage.
IEC 60068-2-39 Test Parameters Table
| Parameter | Description |
|---|---|
| Air Pressure | Simulated low-pressure altitude conditions |
| Temperature | Cold or dry heat conditions depending on test requirements |
| Humidity | Combined humidity stress when applicable |
| Exposure Time | Defined according to product requirements |
| Evaluation | Functional and performance verification |
IEC 60068-2-39 vs Altitude Test Chamber
For products that only need verification under reduced atmospheric pressure, a standard altitude test may be sufficient.
However, when products must operate in environments where low pressure occurs together with temperature variation or humidity exposure, IEC 60068-2-39 testing provides a more comprehensive reliability evaluation.
Typical selection:
| Product Requirement | Recommended Test |
|---|---|
| Aircraft electronics operating at high altitude | Altitude Testing + IEC 60068-2-39 |
| Electronic components exposed to pressure and temperature changes | IEC 60068-2-39 |
| Military equipment reliability verification | MIL-STD-810H altitude testing / IEC 60068-2-39 |
| Semiconductor devices requiring environmental stress evaluation | IEC 60068-2-39 combined testing |
| General altitude simulation | Altitude Testing |
TestEQ Solution for IEC 60068-2-39 and Altitude Testing
TestEQ hypobaric altitude chambers are designed to support advanced environmental simulation requirements, including:
Low air pressure simulation
Temperature control
Humidity testing capability
Combined environmental stress testing
These systems help engineers perform reliable validation for aerospace, defense, automotive electronics, semiconductor, and other high-reliability applications.
TestEQ IEC 60068-2-39 Compliant Hypobaric Altitude Chamber
TestEQ low air pressure test chambers are designed for combined environmental simulation including:
Low pressure
Temperature control
Humidity control
Typical capability:
Pressure adjustment: 5kPa–100kPa
Temperature control
Combined environmental testing
Why Choose TestEQ for IEC 60068-2-39 Low Air Pressure Testing?
TestEQ provides advanced hypobaric altitude chambers designed for reliable low air pressure environmental simulation. With expertise in environmental reliability testing systems, TestEQ helps engineers achieve accurate, stable, and repeatable test results for aerospace, automotive electronics, semiconductor, and high-reliability applications.
Key advantages include:
IEC 60068-2-39 Testing Support
TestEQ chambers are engineered to simulate combined environmental conditions, including low air pressure, temperature, and humidity variations required for reliability validation.
Advanced Environmental Control Technology
Optimized temperature, humidity, and pressure control systems ensure stable test conditions and accurate simulation of extreme environments.
Customized Testing Solutions
TestEQ provides customized chamber designs based on different specimen sizes, test requirements, and industry applications.
Reliable Performance for Critical Industries
TestEQ environmental testing systems support demanding applications in aerospace, defense, automotive electronics, semiconductor, and research laboratories.
Engineering Support and Long-Term Reliability
From system design to installation and technical support, TestEQ works with customers to develop efficient and reliable environmental testing solutions.
IEC 60068-2-39 Applications
IEC 60068-2-39 testing is widely used to evaluate the reliability of products that may operate under low air pressure, temperature, and humidity conditions. This combined environmental testing method helps engineers identify potential failures and improve product durability before products are introduced into demanding environments.
Common applications include:
Aerospace and Aviation Electronics
IEC 60068-2-39 testing helps verify the reliability of avionics, aircraft components, sensors, and electronic systems exposed to high-altitude conditions where reduced air pressure and temperature changes may affect performance.
Defense and Military Equipment
Military electronics and defense systems often require environmental validation under extreme conditions. IEC 60068-2-39 testing helps evaluate equipment reliability in challenging operating environments.
Automotive Electronics
Modern vehicles, especially electric vehicles and advanced electronic systems, use environmental testing to verify the durability of controllers, sensors, communication modules, and other electronic components under combined environmental stresses.
Semiconductor and Electronic Components
Semiconductor devices and electronic assemblies can experience performance changes under low-pressure environments. IEC 60068-2-39 testing helps manufacturers evaluate product stability, insulation performance, and long-term reliability.
Industrial and Research Equipment
Industrial instruments, measurement devices, and specialized equipment may require validation under simulated altitude environments to ensure safe and stable operation.
By applying IEC 60068-2-39 testing, manufacturers can better understand product limitations, reduce field failures, and improve reliability in real-world applications.
Frequently Asked Questions About IEC 60068-2-39 Low Air Pressure Testing
1. What is IEC 60068-2-39?
IEC 60068-2-39 is an environmental testing standard that evaluates products under combined low air pressure, temperature, and humidity conditions. It is commonly used to verify the reliability and performance of electronic components, aerospace equipment, and industrial products in high-altitude environments.
2. What is a low air pressure test chamber?
A low air pressure test chamber is an environmental simulation system designed to reproduce reduced atmospheric pressure conditions. It allows engineers to evaluate product performance under altitude-related environments while controlling temperature, humidity, and pressure parameters.
3. What is the difference between altitude testing and IEC 60068-2-39?
Altitude testing mainly focuses on simulating reduced atmospheric pressure at high elevations, while IEC 60068-2-39 evaluates combined environmental stresses including low pressure with temperature and humidity conditions. It provides a more comprehensive reliability evaluation method.
4. Which industries use IEC 60068-2-39 testing?
IEC 60068-2-39 testing is widely used in aerospace, aviation electronics, defense systems, automotive electronics, semiconductor devices, telecommunications equipment, and high-reliability industrial applications.
5. Does IEC 60068-2-39 require temperature and humidity testing?
Yes. IEC 60068-2-39 focuses on combined environmental conditions, which may include low air pressure together with temperature and humidity stresses. These combined tests help identify failures that may not appear under normal atmospheric conditions.
6. What chamber is used for low pressure testing?
Low pressure testing is typically performed using a hypobaric altitude chamber or altitude simulation chamber. These systems combine pressure control with temperature and humidity regulation to reproduce high-altitude environmental conditions.
7. Can IEC 60068-2-39 simulate aircraft altitude environments?
Yes. IEC 60068-2-39 test systems can simulate reduced pressure environments similar to high-altitude conditions experienced by aircraft, avionics equipment, and aerospace components during operation.
8. How does TestEQ support IEC 60068-2-39 testing?
TestEQ provides customized hypobaric altitude chambers designed for IEC 60068-2-39 environmental simulation. The systems integrate low pressure control, temperature regulation, and humidity management to support reliable product validation for aerospace, electronics, and industrial applications.
Internal Linking Module
Recommended Equipment
Related Test Equipment for IEC 60068-2-39 Low Pressure Testing
Simulates high-altitude and low-pressure environments for aerospace, defense, electronics, and reliability testing applications.
2. Temperature Humidity Chamber
Provides precise temperature and humidity control for environmental reliability tests based on IEC 60068 and other international standards.
Designed for repeated temperature cycling tests to evaluate product reliability under changing environmental conditions.
Related Standards
Related Environmental Testing Standards
1. IEC 60068 Environmental Testing Standard
Provides an overview of IEC 60068 environmental testing methods, including temperature, humidity, vibration, and combined environmental tests.
2. MIL-STD-810H Environmental Testing Standard
Explains military environmental testing requirements for equipment exposed to extreme temperature, altitude, humidity, vibration, and shock conditions.
3. RTCA DO-160 Environmental Testing Standard
Covers environmental qualification testing requirements for airborne equipment and avionics systems.
Technical Resources
Related Guides for Low Pressure and Environmental Testing
1. What Is Altitude Testing? Complete Guide for Reliability Testing
Explains altitude simulation testing methods, applications, and how low-pressure environments affect product reliability.
2. How to Choose an Environmental Test Chamber
Provides guidance on selecting environmental test chambers based on temperature range, humidity control, testing standards, and applications.
3. MIL-STD-810H Altitude Test Method Guide
Introduces MIL-STD-810H altitude testing procedures and explains the differences between military and commercial environmental testing requirements.
CTA
Need an IEC 60068-2-39 Low Pressure Test Solution?
TestEQ provides advanced hypobaric altitude chambers designed for IEC 60068-2-39 combined environmental testing, including low air pressure, temperature, and humidity simulation.
Our reliability testing systems help aerospace, automotive, semiconductor, and electronic manufacturers validate product performance under extreme environmental conditions.
Contact TestEQ engineers to discuss your IEC 60068-2-39 testing requirements and customized chamber solutions.
