IEC 60068: A Complete Guide to Environmental Testing for Electronic Components

IEC 60068 represents the international reference for environmental testing of electronic and electromechanical componentsand materials intended to operate in variable climatic conditions. Published by the International Electrotechnical Commission (IEC), this series of standards defines procedures for testing the resistance of devices and components to extreme temperatures, humidity, thermal cycling, and other environmental stresses.

In this guide, we analyze the main tests of the IEC 60068 series, the required test conditions, the industrial sectors that adopt them, and the FDM environmental chambers designed to perform them with maximum precision.

What is IEC 60068 and why is it the reference standard?

The IEC 60068 series, officially titled "Environmental Testing," is a family of standards comprising dozens of subparts, each dedicated to a specific environmental test. The tests are identified by letters (A for cold, B for hot, N for thermal cycling, etc.) and progressive numbers that identify the specific procedure.

There are many reasons why IEC 60068 has become the reference standard in the electronics sector:

• International harmonization: Adopted as EN 60068 in Europe, the standard ensures that tests are comparable worldwide.
• Comprehensive coverage: From temperature to humidity, from pressure to vibration, the series covers all relevant environmental stresses.
• Precise requirements: each sub-part defines test conditions, tolerances, durations and acceptance criteria, eliminating ambiguity.
• Regulatory Recognition: It is recognized by industry standards such as MIL-STD-810 for defense, JEDEC for semiconductors, and ISO 16750 for automotive.

For electronic component manufacturers, passing IEC 60068 tests is often a prerequisite for accessing international markets and obtaining product certification.

The main tests of the IEC 60068 series

The IEC 60068 series comprises over 80 subparts. Below, we analyze the five most requested climatic tests in the electronics industry, the ones that every qualification laboratory must be able to perform.

IEC 60068-2-1 — Test A: Cold

IEC 60068-2-1 defines the procedures for testing the ability of components and devices to withstand and function at low temperatures. The standard includes three main variants:

• Ab (non-dissipative cold): The sample is not powered during the test. Mechanical and structural strength is evaluated at temperatures from -65°C to +5°C.
• Ad (dissipative cold): The sample is powered and functioning. Correct electrical operation at low temperatures is verified.
• Ae (gradual cold): The temperature is reduced at a controlled rate to simulate real-world conditions.

Typical conditions: temperatures from -65°C to +5°C, durations from 2 to 96 hours depending on the required severity. The FDM T-PRO series thermostatic chambers reach -70°C, covering the entire range required by the standard.

IEC 60068-2-2 — Test B: Dry heat

IEC 60068-2-2 tests the resistance of components and materials to high temperatures in low humidity conditions. This test also includes dissipative and non-dissipative variants:

• Bb (non-dissipative dry heat): The sample is not powered. Range from +30°C to +1000°C, duration from 2 to 1000 hours.
• Bd (dissipative dry heat): The sample is in operation. It is verified that the electrical performance remains within the specified limits.

Typical conditions: For electronic components, the most common temperatures are +85°C, +125°C, and +155°C. FDM environmental chambers with ranges up to +180°C cover the needs of most qualification tests.

IEC 60068-2-14 — Test N: Temperature variation (Thermal Cycling)

IEC 60068-2-14 is among the most critical tests for electronic components: it subjects samples to rapid temperature variations to highlight defects related to thermal fatigue, differences in material expansion, and soldering. The standard defines three methods:

• Na (rapid transfer): The sample is transferred rapidly between two zones at different temperatures. With two chambers, the transfer time should not exceed 3 minutes; for large samples, the standard permits longer times.
• Nb (controlled gradient variation): the temperature in the chamber changes at a rate of 1 to 15 K/min. The sample remains in the same chamber throughout the cycle.
• Nc (fluid bath): The sample is immersed alternately in hot and cold baths for maximum thermal shock.

Typical conditions: Cycles between -40°C and +125°C with ramps from 5 to 15 K/min, 100 to 1000 cycles. The C-BCXPRO series FDM climate chambers offer programmable ramps and multi-step profiles ideal for these tests.

IEC 60068-2-30 — Test Db: Cyclic damp heat

IEC 60068-2-30 evaluates the resistance of components to condensation and moisture penetration through controlled temperature and humidity cycles. Unlike steady-state tests, the cycles cause condensation to form and reabsorb on the surface of the specimens.

The standard cycle includes:

• Hot phase: rise in 3 hours to 40°C (or 55°C in the severe variant) with humidity of at least 95% RH, during which condensation forms on the sample; then maintenance at 93% RH for up to 12 hours from the start of the cycle
• Cold phase: drop to 25°C in 3-6 hours and remain at 25°C with humidity of at least 95% RH until the end of 24 hours
• Number of cycles: 2, 6, 12, 21 or 56 at 40°C; 1, 2 or 6 at 55°C (each cycle lasts 24 hours)

This test is particularly relevant for protective coatings, connectors, and PCBs exposed to tropical environments. Proper execution requires a climate chamber with precise humidity control and gradual transitions.

IEC 60068-2-78 — Cab test: Steady damp heat

IEC 60068-2-78 maintains the specimen at constant temperature and humidity, without condensation: 30°C or 40°C with 85% or 93% relative humidity, for durations from 12 hours to 56 days.

The 85/85 test (85°C and 85% RH, typically 168 to 1000 hours), one of the most widespread tests in the semiconductor and power electronics industry, is the accelerated version of this test but belongs to another standard: the Test Cy of IEC 60068-2-67 and, for semiconductors, the THB of JEDEC JESD22-A101.

What happens:

• Resistance to electrochemical corrosion
• Ionic migration between conductive tracks
• Degradation of electrical insulation
• Delamination of encapsulants and coatings

The 85/85 test is required by JEDEC (JESD22-A101), the automotive industry (AEC-Q100/Q200), and photovoltaic standards (IEC 61215). The C-PRO Series FDM chambers provide the long-term temperature and humidity stability required for these extended tests, with tolerances that meet the standard's requirements.

Sectors requiring IEC 60068

The IEC 60068 series isn't limited to consumer electronics. Here are the main industrial sectors that use it as a reference for product qualification:

Like FDM it supports IEC 60068 tests

FDM Environment Makers designs and manufactures environmental test chambers specifically configured for IEC 60068 series testing. Each chamber is customizable for temperature range, ramp rate, and humidity control to meet your laboratory's needs.

All FDM chambers are equipped with a programmable controller with multi-step profiles, continuous data recording, and a remote interface. For laboratories requiring the entire IEC 60068 series, FDM offers customized solutions with multiple chambers integrated into the same management system.

Learn more: Discover our climate chamber for testing electronic batteries, designed and manufactured by FDM Environment Makers.

Further information on individual IEC 60068 tests

Explore our dedicated guides to each test in the IEC 60068 series:

• IEC 60068-2-1: Complete Guide to Cold Testing
• IEC 60068-2-14: Temperature Variation Test (Thermal Cycling)
• IEC 60068-2-78 and Test 85/85: Conditions and Differences

Authoritative Sources and External Links

To learn more about the IEC 60068 series and related standards for electronic environmental testing:

• IEC Webstore — IEC 60068 series — Direct access to the official 60068 series parts catalog on the IEC webstore.
• CENELEC — European Committee for Electrotechnical Standardization which implements IEC 60068 into EN standards (e.g. EN 60068-2-1 for cold testing).
• UL Solutions — A certification body that performs accredited IEC 60068 compliance testing of electronic products destined for the North American and European markets.
• CEI — Italian Electrotechnical Committee — Implements IEC 60068 as the CEI EN 60068 series, the Italian reference standard for electronic environmental testing.
• IECEE — CB Scheme — International mutual recognition system for IEC tests for electronic products, which includes IEC 60068 environmental tests.

Frequently Asked Questions about IEC 60068

What is the difference between IEC 60068 and EN 60068?

There is no technical difference. EN 60068 is the European version of IEC 60068, adopted by CENELEC. The requirements are identical: a component tested according to IEC 60068-2-1 automatically also satisfies EN 60068-2-1.

How many subparts does IEC 60068 have?

The series includes over 80 subparts, organized into three groups: Part 1 (general guidelines), Part 2 (specific test procedures) , and Part 3 (supporting information). For electronic component qualification, Parts 2-1, 2-2, 2-14, 2-30, and 2-78 are the most popular.

Is the 85/85 test mandatory?

The 85/85 test (IEC 60068-2-67, or JEDEC JESD22-A101 for semiconductors) is not required by law, but is in fact required by most qualification programs in the semiconductor (JEDEC), automotive (AEC-Q), and photovoltaic (IEC 61215) industries. Without passing the 85/85 test, a component is not accepted into the supply chain.

What tolerances does IEC 60068 require?

Tolerances vary by subpart, but in general, the standard requires ±2°C for temperature and ±3-5% for relative humidity. FDM chambers are designed to ensure stability and uniformity within these limits.