EMP & Faraday Protection: A Buyer's Guide for Preppers and Survivalists

What Is an EMP and Why Should You Care?

An electromagnetic pulse, commonly called an EMP, is a sudden burst of electromagnetic energy that can disrupt, damage, or destroy electronic devices. EMPs are usually discussed in three main categories: high-altitude nuclear detonation, a major solar event such as a coronal mass ejection, or a localized non-nuclear EMP device.

A high-altitude nuclear EMP can create multiple types of electromagnetic effects that impact different classes of electronics and electrical infrastructure. A severe solar storm, such as the Carrington Event of 1859, could also cause serious damage to the electrical grid and connected systems. While the exact impact of any EMP event would depend on its source, strength, location, and duration, the concern is simple: modern life depends heavily on electronics.

Communications, transportation, medical equipment, banking systems, fuel distribution, food logistics, and emergency response networks all rely on electronics and power infrastructure. A serious EMP or solar event could create cascading failures across multiple systems at the same time. For preppers and survival-minded individuals, protecting key electronics is a practical part of a larger preparedness plan.

What Is Faraday Protection?

A Faraday cage is an enclosure made from conductive material that helps block electromagnetic fields. The concept is named after scientist Michael Faraday. In simple terms, the conductive outer layer redirects electromagnetic energy around the outside of the enclosure, helping protect the items inside.

Faraday protection comes in several common forms:

Faraday bags are flexible pouches lined with conductive material. They are commonly used for phones, radios, GPS units, small hard drives, and other compact electronics.

Faraday boxes are rigid containers, usually made from or lined with conductive material. They can offer stronger physical protection and are useful for larger or more valuable electronics.

Faraday rooms or full Faraday cages are larger enclosures designed to protect bulkier equipment or high-value systems.

For most preppers, Faraday bags and boxes are the most practical starting point. The goal is not to protect every electronic device you own. The goal is to protect the devices you would truly need in a grid-down emergency.

What Should You Put in a Faraday Cage?

Focus first on electronics that support survival, communication, navigation, medical needs, or power management. These are the items that may be difficult or impossible to replace during an emergency.

Common items to consider include:

Communications equipment such as handheld ham radios, GMRS radios, AM/FM receivers, and backup communication devices.

Navigation tools such as backup GPS units, offline map devices, and compact electronic navigation aids.

Medical electronics such as hearing aids, blood glucose monitors, insulin pump accessories, or other medically necessary electronic devices.

Power management equipment such as solar charge controllers, MPPT regulators, inverter control boards, and small battery management components.

Data storage devices such as backup hard drives, USB drives, encrypted storage devices, offline maps, scanned IDs, insurance documents, medical records, and other critical files.

Vehicle and equipment parts such as backup ignition components, electronic control modules, or small replacement parts for generators and older vehicles.

Older vehicles with carbureted engines and mechanical ignition systems are generally less dependent on sensitive electronics than modern vehicles. If post-EMP transportation is part of your preparations, an older carbureted truck, tractor, or generator with minimal electronic controls may be worth considering.

What to Look for in a Faraday Bag

Attenuation Rating

Attenuation measures how much signal a Faraday bag blocks. It is usually measured in decibels, or dB. As a rule, look for bags rated at 60 dB or higher. Some higher-end Faraday bags advertise ratings in the 80 to 90 dB range.

A bag with no published attenuation rating should raise questions. If a manufacturer will not tell you how much signal the bag is designed to block, it is difficult to know what level of protection you are buying.

Layer Count

Higher-quality Faraday bags usually use multiple conductive layers. These may include materials such as nickel-copper fabric, carbon-based conductive fabric, or conductive foil layers. Dual-layer and triple-layer designs typically provide better shielding than thin single-layer products.

Layer count alone does not guarantee quality, but it is one factor to consider when comparing bags.

Seam and Closure Design

The seams and closures are often the weakest points on a Faraday bag. Even if the body of the bag uses good shielding material, a poor closure can create a gap where radio frequency energy can leak through.

Look for features such as rolled seams, double-stitched conductive seams, roll-top closures, fold-over flaps, or multiple closure points. A simple zipper by itself is usually not ideal unless it is backed by a conductive flap or another shielding layer.

Size and Practical Use

Choose the size based on what you plan to protect. Small bags work well for phones, handheld radios, GPS units, and USB drives. Larger bags are better for multiple radios, backup hard drives, tablets, small solar components, and compact power management equipment.

Some preppers also build larger Faraday storage containers using metal trash cans, ammo cans, or steel boxes lined with insulating material. The key is to make sure the electronics do not touch the bare metal directly and that the lid creates continuous conductive contact around the opening.

Testing Your Faraday Bag

You should test any Faraday bag before relying on it. A simple first test is to place a phone inside the fully sealed bag and call it. If the phone rings or receives a notification, the bag is not blocking signals effectively.

This test is useful, but it is not perfect. Cellular, Wi-Fi, Bluetooth, GPS, and radio frequencies can behave differently. For more serious testing, use a signal meter or test with multiple types of devices and frequencies. The more critical the device, the more seriously you should test the protection.

Building a Faraday Protocol

Faraday protection only works if your electronics are already protected before an event happens. That means you need a simple system, not just a bag sitting in a closet.

A practical Faraday protocol might include keeping one backup radio permanently sealed in a Faraday bag while using a separate radio for daily or training use.

Store backup data drives, scanned documents, and critical files in a sealed Faraday container at home or at a bug-out location.

Rotate stored electronics on a schedule so batteries stay charged and devices remain functional.

Label each bag or container clearly so you can find the right item quickly under stress.

Keep charging cables, adapters, spare batteries, and printed instructions with the protected devices whenever possible.

The goal is to make the system easy enough that you will use it. Complicated preparedness plans tend to fail when people are tired, rushed, or under pressure.

EMP Protection and Body Armor: The Full Preparedness Picture

Preparedness is built in layers. Faraday protection helps preserve your ability to communicate, navigate, store information, and manage power during a major disruption. Body armor, plate carriers, helmets, and other defensive equipment protect you physically if infrastructure fails and civil order becomes unstable.

EMP preparedness and ballistic protection are not competing priorities. They solve different problems. A well-rounded readiness plan considers power, communication, water, food, medical needs, transportation, and personal security.

Protecting your electronics is one part of that plan. Protecting yourself and your family is the next layer. Browse our body armor collection and plate carriers, explore Faraday bags and EMP protection gear, and check out our gas masks buying guide and ReadyWise emergency food review, and our body armor laws by state guide to round out your preparedness plan.