Electromagnetic interference (EMI) testing is an important aspect of developing and launching an electronic device. It involves measuring the disruption a device can cause to other devices that operate around it due to radiated and conducted emissions.

As an electronics manufacturer, almost all countries require your device to pass EMI testing in an accredited lab before it can go on sale. In the United States, EMI is regulated as part of the FCC Part 15 rules, which apply to electronic devices.

As an accredited electronics testing lab, we can test your device for EMI and verify that it fully complies with EMC standards such as FCC Part 15 and the EU’s EMC Directive. To request a quote or ask our team a question, contact us online or call us at 866-540-5287. 

Below, you can learn more about what electromagnetic interference is, how EMI testing works, as well as common EMI and electromagnetic compatibility (EMC) standards that your product will need to comply with to enter the US and/or EU markets.

What is EMI?

Electromagnetic interference refers to disruption caused by one electronic device to others due to emitted electromagnetic fields.

Almost all devices are capable of releasing electromagnetic energy, which is usually referred to as emissions. These emissions can cause other devices to malfunction, give false readings, or simply stop working as a result of interference.

You’ve likely experienced the effects of EMI before if you’ve used an electronic device in a room with multiple other devices. For example, you may have noticed a loss of radio or TV signal as a microwave, phone or other device operates nearby. 

EMI can be either radiated or conducted. Radiated EMI travels through the air, similar to a radio wave. Conducted EMI is emitted via power cables, signal cables and other conductive materials connected to a device. 

There are many sources of EMI, from cell phones and computers to industrial machinery, power lines and other equipment. 

How EMI Testing Works

EMI testing is conducted to ensure that electronic devices comply with specific standards and don’t emit harmful levels of electromagnetic radiation that could interfere with other devices. 

Testing for EMI is critical not just for ensuring that your device works properly, but also to verify that it complies with all applicable regulations and standards.

In the United States, the most important EMI standard is the Code of Federal Regulations, Title 47, Part 15, or as it’s more commonly known, FCC Part 15.

This standard sets limits on the amount of electromagnetic emissions a device can produce, as well as its ability to withstand emissions from other devices. Devices need to be tested to verify that they comply with FCC Part 15 before they can go onto the market in the United States.

The process of EMI testing generally involves placing your electronic device inside a controlled test environment, such as an anechoic chamber. This is a shielded testing area in which noises and reflections of electromagnetic waves are dampened, allowing for accurate testing. 

Inside this chamber, your device is subjected to various electromagnetic environments that are designed to simulate real-life use. Special testing instruments, such as spectrum analyzers and antennas, are used to measure emissions from your electronic device. 

Compliance with EMI and EMC regulations requires testing for both emissions from your device and your device’s immunity, or its ability to withstand interference from other devices. 

For more information about the EMI and EMC testing process, you can contact us online or call us at 866-540-5287 to talk to our engineering team. 

Common EMI & EMC Standards

To regulate and standardize EMI testing, several standards have been established globally. Key EMI and EMC standards include FCC Part 15, the European Union’s EMC Directive and Radio Equipment Directive (RED), and international standards set by the IEC:

• FCC Part 15. Regulated by the Federal Communications Commission, FCC Part 15 sets limits on radiofrequency energy emissions. Compliance with FCC Part 15 is essential for electronic devices that are sold in the United States.
• EU EMC Directive. In the European Union, the EMC Directive is the key regulation that governs electromagnetic interference. Like FCC Part 15, it sets specific criteria for safety and performance for electronic devices.
• EU RED Directive. The Radio Equipment Directive is a separate regulation that governs radio equipment that’s sold in the European Economic Area, including cell phones, Wi-Fi routers and other devices.
• IEC standards. The International Electrotechnical Commission (IEC) publishes its own standards for electromagnetic compatibility that are used as baseline standards in many countries. 

Contact Us for EMI Testing Help & Information

Completing EMI testing is a key step in verifying that your device complies with regulations and is ready to enter the market. 

As an accredited testing lab, we’ve helped hundreds of manufacturers achieve compliance with FCC and European standards, including FCC Part 15 and the EMC/RED Directives.

To request a quote for testing your device, or to ask our engineers a question about testing and compliance, contact us online or call us at 866-540-5287.