IEC 61000-4-2 ESD Testing: Immunity to Static Discharge
How electrostatic discharge testing works, the difference between contact and air discharge, test levels and where products most often fail.
3 min readOctober 14, 2026
What Does the Test Measure?
In daily life, devices constantly operate inside fields created by radios, mobile phones, Wi-Fi routers and broadcast transmitters. IEC 61000-4-3 measures whether a device keeps working correctly when exposed to such fields.
During the test, an electromagnetic field of a set strength and frequency is applied to the device while its behavior is monitored. A frozen screen, a drifting reading or a lost link is assessed against the performance criterion in the product standard.
Levels and Frequency Range
The field strength used in the test is expressed in volts per meter (V/m). Common levels are 3 V/m for home and office products and 10 V/m for industrial products. Automotive and military standards can demand much higher values.
The frequency range is typically 80 MHz to 6 GHz. The signal is amplitude-modulated with a 1 kHz tone to mimic real transmitters, and the frequency is swept step by step. That's why the test can take several hours per device.
Why Is a Shielded Room Needed?
The field generated in the test is strong enough to disrupt nearby radio and telecom services. The test must therefore be done in a room that leaks no signals outside. Reflections must also be controlled so the field is uniform in front of the device.
These two requirements mean the test must be done in a semi-anechoic chamber or an absorber-lined test chamber. The chamber is validated with a field uniformity measurement to the standard; tests run before it passes aren't accepted.
What to Watch in Pre-Testing
The most common mistake in in-house pre-testing is laying out cables differently from the certification lab. Because cables pick up the field, their length and position directly affect the result.
We can help you define the right test setup and chamber size for your product. Our solutions for electronics manufacturers range from pre-test chambers to full test chambers.
Frequently Asked Questions
What equipment does the test need?
The core equipment is a signal generator, power amplifier, transmitting antenna and field probe. Amplifier power is chosen by the required field strength and test distance.
What is a field uniformity measurement?
It shows the field is distributed evenly enough over the plane where the device will sit. It is repeated at chamber handover and after major changes.
Does failing mean a design flaw?
It can usually be solved with small changes to cabling and grounding. Finding the problem in pre-testing makes the fix much easier.
Related Solutions
Let's Find the Right Solution for Your Project
Get a QuoteYour free site survey and quote will be ready within 24 hours.