Is Protection Against Electromagnetic Interference Necessary?

Electromagnetic Interference (EMI) is an electric field that can interfere with how electronic devices function. Applications of devices that can stop working because of magnetic fields include the medical, military, aerospace, railroad, and mass transit industries. Therefore, it is imperative to add protection against electromagnetic interference when manufacturing sensitive equipment. 

It’s imperative to invest in EMI shielding to ensure equipment keeps fulfilling its function without electronic interference, especially in medical applications where protection against electromagnetic interference can be the difference between life and death. 

What is EMI Shielding?

EMI shielding is the act of preventing interference in equipment from external electrostatic and electromagnetic fields and radio frequency waves. Different EMI shielding materials determine the shielding effectiveness in equipment. Some shielding materials work better for strong electromagnetic (EM) fields than others. 

You need an EMI shielding expert to assist you in deciding the best shielding materials when manufacturing medical, military, or rail and mass transit equipment. The strength of the EMI for equipment should determine the shielding materials that a manufacturer should use. 

Why is it Important?

Electromagnetic interference can affect many electronic devices and systems that have critical applications daily. It is essential to ensure that EMI doesn’t affect important systems and electronic devices that offer crucial services across various industries. Some of the devices vulnerable to EMI are used in the following industries and applications:

•  Medical
•  Military
•  Railway & Mass Transit
•  Control & Navigation Systems 
•  Vehicular Control Systems 
•  Aerospace Electronics

EMI shielding can prevent a catastrophe by ensuring essential control and navigation systems work as they should. Also, it deflects electromagnetic waves and reduces the odds of malfunction in communication devices.

EMI shielding increases the reliability of your devices, and you can expect the best performance from machines outfitted with EMI protection. Customers will be more satisfied with products that feature EMI shielding due to the efficiency of the devices and systems. 

There are regulations that compliance organizations provide about systems and devices that are at risk of electromagnetic interference. Therefore, it would be in your best interest to use protection against EMI and meet regulatory bodies’ compliance requirements. 

Sources of EMI

There are natural and artificial sources of electromagnetic interference. Natural magnetic fields occur when charged particles are accelerated. Examples of natural sources of electromagnetic fields are storms, including electric storms, rain spray, lightning discharge, and solar radiation, among other natural occurrences. 

Man-made EMI sources are plentiful because many devices use electrons nowadays, from home appliances to communication devices. The most popular sources of human-made magnetic fields include high-frequency devices, microwave equipment, electric motors, cell phones, radios, and power lines, among others. 

Therefore, there is a significant probability that critical devices and systems can face EMI when suitable shielding materials are not in place. It is essential to consider both natural and human-made EMI sources when selecting shielding materials to use in your design. 

You cannot forgo shielding in design production because there is a high probability that your design will come into contact with magnetic materials at one point or another. It is best to be prepared for all possibilities when designing critical systems and devices. 

How to Protect Against EMI

The best way to protect against electromagnetic interference is by identifying the source, its path, and the victim. This makes it simple to locate where EMI comes from and the best approach to prevent it. 

There are electromagnetic compatibility (EMC) guidelines that stipulate various techniques manufacturers can use to keep electromagnetic fields at regular rates. The methods and techniques that manufacturers use depend on the strength of electromagnetic fields that devices produce. Some of the popular methods include Faraday cages, EMI gaskets, and conductive silicone and composite enclosures. 

Faraday Cages 

Michael Faraday invented Faraday cages, a protective shield that keeps electromagnetic radiation from getting inside of the cage, in 1836. And nearly 200 years later, they are still an effective method of preventing external electromagnetic fields from interfering with electrical equipment. Manufacturers use metal foils in alternating layers to create a cage that can resist electromagnetic waves. 

A popular material for a Faraday cage is expanded metalized foils because they are electrically continuous and flexible. Metal foils are lightweight, making them perfect for a portable Faraday cage. It makes it easy to overlay the foils with small spaces. 

Faraday cages are also popular because they contain electromagnetic fields emitted by devices in the cage from affecting devices and systems outside the cage. Overall, these tools are perfect for protecting devices and systems that you want to keep safe from external EM fields. 

EMI Gaskets 

EMI gaskets protect your devices by presenting a conductive covering on electronic enclosures or seams to prevent leaks of EM fields. Early EMI gaskets used thin metal sheets that would collapse under strong EM fields, leading to leaks. It is rare to find gaskets made of thin metal sheets due to technological advancements. 

Modern EMI gaskets use metal foam or metal screens to create a complex surface that reduces electromagnetic interferences in devices and systems. The materials are flexible and can be transformed to fit various enclosures and seams. Overall, the use of EMI gaskets is an effective way to protect against EMI. 

Conductive Silicone and Composite Enclosures 

Composite materials like carbon fiber reinforced plastics are becoming popular as a way to protect against EMI. Conductive silicone is a material made from particle-filled silicone, and it is effective in protection against EMI. 

Conductive silicone and composite enclosures protect against EMI by absorbing the energy and spreading it over the conductive material. Therefore, the waves are canceled and unable to interfere with devices or systems. 

Both conductive silicone and composite enclosures need reinforcements, like expanded foil or a mesh gasket, to prevent EM leaks. Expanded metal foils are the most popular reinforcement materials because they are compatible with multiple manufacturing processes. The reinforcements ensure that the final shielding is effective in canceling EM waves. 

Geospace Technologies—Your EMI Protection Experts 

It’s best to protect against EMI whether you are manufacturing consumer products like cell phones or creating navigation systems for aerospace industries. Natural and artificial EM fields can interfere with the performance of devices or systems, and providing adequate protection against EMI is the manufacturer’s duty. 

Geospace Technologies provides a full suite of services for designing devices and systems under one roof so you don’t need to use third parties to ensure that your products are EMC compliant. Moreover, we are located in the U.S.A., and you can get your products within a short lead time. 

Our team of experts will offer advice on the best shielding materials to use in your devices and the best techniques to protect devices against EMI. We have a long history of manufacturing top-notch products that meet all industry requirements on the first inspection. Contact our experts for more helpful information on design modifications and other cost-effective methods of achieving protection against electromagnetic interference.