Saturday, June 22, 2024

What is EMI/RFI Shielding & Why it is Important?

You might have heard that all electronics emit some waves or signals that can potentially interrupt the performance of another electronic product. So, what exactly these waves or signals are?

Every electronic device produces electromagnetic waves, known as interferences, interrupting other electronics and damaging the equipment. These electrical noise interferences are known as Electromagnetic interference (EMI). Regarding electrical noise, the terms EMI and RFI are often used interchangeably. However, there’s a slight difference between these two. While EMI is used in electrical noise, RFI is used for the radio frequency spectrum.

EMI and RFI can be generated inside a single product or externally from another device. Several sources are responsible for producing EMI/RFI that are both artificial and natural sources, such as mobile phones, car ignition systems, thunderstorms, the northern lights, and televisions, to name a few. These interferences disrupt other electronic devices’ performance and result in equipment failure. So, to control the ingress and egress of these interferences, design engineers need to use shielding. Now, let’s take a look at EMI/RFI Shielding.

What is EMI/RFI Shielding?

Engineers use the shielding technique to ensure that an electronic device doesn’t emit signals and meets various EMI-RFI standards. When eliminating EMI is impossible, the best viable solution is to use an EMI-RFI shielded enclosure. Various medical, military, and aerospace electronics that transmit signals need shielding.


EMI Shielding is the technique of protecting an electronic from external electromagnetic signals that disrupt its functioning. Shielding also helps block its internal signal to prevent it from leaking out and interfering with surrounding electronics. This method applies a conductive material to electronic enclosures as a spray.

The concept of shielding is based on the principle of the Faraday cage. A metallic screen is installed to absorb electromagnetic interference. For shielding, magnetic alloys that are highly absorbent are used. Pure elements such as silver, copper, and nickel are best for shielding because of their ability to reflect electromagnetic radiation. However, a metallic box of highly conductive material is quite costly and not cost-effective for design engineers. So, to minimize the cost, engineers often spray EMI-RFI shielding agents on plastic enclosures.

Why is EMI-RFI Shielding Important?

The EMI/RFI Shielding is used across many industries. Several electronic devices are used for various operations, from the medical industry to the military. A major consideration of every enterprise is to make sure that their equipment and devices work properly. When electronic devices stop working when they’re most needed, it can result in huge losses. So, to prevent electronics from malfunctioning, industries use EMI-RFI shielding.

For instance, EMI/RFI Shielding is essential for the Telecomm industry to prevent incorrect frequencies from interfering with a device. Likewise, shielding protects medical equipment from interferences that can potentially damage the equipment and severely impact patients’ well-being. In a nutshell, EMI/RFI shielding is used in every application that needs protection from electronic disturbance to prevent equipment failure and keep operations running at peak performance.

William J. McGoldrick
William J. McGoldrick
Passionate beer maven. Social media advocate. Hipster-friendly music scholar. Thinker. Garnered an industry award while merchandising cannibalism in Gainesville, FL. Have some experience importing human hair in Minneapolis, MN. Won several awards for consulting about race cars in the government sector. Crossed the country developing strategies for clip-on ties in Washington, DC. Spent a weekend implementing Virgin Mary figurines in West Palm Beach, FL. Had moderate success promoting Elvis Presley in Ocean City, NJ.

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