Electromagnetic Pulse (EMP) Testing

Electromagnetic pulses (EMPs) are a growing concern worldwide. EMPs, also known as direct energy weapons are being used by military and law enforcement in a variety of ways. These EMP weapons have the ability to impact electronics in a variety of ways ranging from just temporarily interrupting operations to completely destroying them.

As more and more adversaries gain this technology, the importance of being prepared has increase exponentially.

What is an EMP?

An electromagnetic pulse (EMP) is a short burst of electromagnetic energy that can be extremely damaging to electronic equipment and electrical devices. EMP energy can be transferred in the form of electromagnetic radiation, an electric field, electrical conduction or a magnetic field. Since EMPs have a short duration, their impact can occur across a large range of frequencies.

The pulses of an EMP are characterized based on:

• Type of energy
• Range of frequencies
• Their pulse waveform

The type of energy can be conducted, electric magnetic or nuclear. The waveform characteristics include the amplitude, duration and shape.

How are EMPs produced?

EMPs can be produced naturally, occur from man-made equipment. Natural EMPs include lightning strikes and electrostatic discharges (ESD), geomagnetic storms/coronal mass ejections of solar origin.

On the other hand, Man-made EMPs include power line surges, pulses created by ignition systems, nuclear electromagnetic pulses (NEMP) and non-nuclear electromagnetic pulses (NNEMP). Additionally, military EMPs can be either nuclear in origin or non-nuclear.

What are NEMPs and HEMPs?

NEMP stands for Nuclear Electromagnetic Pulse. A NEMP is a quick pulse of electromagnetic radiation resulting from a nuclear explosion that causes damaging current and voltage surges. The radiation emitted can impact the surrounding air by ionizing it. This creates a secondary EMP since the atoms of air lose their electrons and then regain them.

A high-altitude electromagnetic pulse (HEMP) produces gamma rays that are converted to EMP in the mid-stratosphere. These EMPs have an impact over a wide area within the line of sight of the detonation.

By occurring in the thinner air of higher altitudes, the EMP is much stronger.

What are EMP testing, NEMP testing and HEMP testing?

EMP testing can be completed using either an induced pulse simulation or a threat pulse simulation.

An induced pulse simulation is conducted using a current clamp. The EMP test lab will reverse the clamp to inject a damped sine wave signal into a cable connected to the device under test. This damped sine wave generator is can replicate the signals that most commonly occur.

Additionally, the threat pulse simulation is conducted by using an EMP generator. The size of the generator will vary from handheld to large outdoor test facilities. The EMP testing lab will use a low-level pulse to characterize the victim’s response prior to the damped sinewave injection.  The EMP test can be completed using pulses at high energy to simulate the actual conditions of the threat.

How important is EMP testing?

In 2019, the President issued an executive order on coordinating national resilience to electromagnetic pulses. This order spoke to the dangers of EMPs, NEMPs and HEMPs. Furthermore, those dangers include the potential to disrupt, degrade, and damage technology and infrastructure.

These electromagnetic pulses can affect large geographic areas, disrupting elements critical to the Nation’s security. Other factors that could be involved include economic prosperity, global stability, and commerce.

The order states that “The Federal Government shall provide incentives, as appropriate, to private-sector partners to encourage innovation that strengthens critical infrastructure against the effects of EMPs through the development and implementation of best practices, regulations and appropriate guidance.”

What are the most common test standards used in NEMP testing and HEMP testing?

MIL-STD-461 is the foundational U.S. military standard that governs Electromagnetic Compatibility (EMC), ensuring military equipment can operate reliably amidst electromagnetic interference (EMI). Within this standard, specific tests address the unique, severe threats posed by an Electromagnetic Pulse (EMP), particularly a High-Altitude EMP (HEMP) generated by a nuclear event.

These tests are categorized as “Susceptibility” or “Immunity” checks, focusing on the equipment’s ability to survive powerful, fast-rising electromagnetic energy.

RS105 (Radiated Susceptibility, Transient Field)

RS105 assesses the device’s radiated immunity against the raw, high-intensity Electric Field (E-field) of an EMP. This test directly evaluates the shielding effectiveness of the equipment’s enclosure or box. It uses an extremely fast, single, high-voltage pulse with a nanosecond-scale rise time to simulate the direct electromagnetic threat coupling onto the equipment’s surface.

CS116 (Conducted Susceptibility, Damped Sinusoids)

CS116 addresses the secondary effects of an EMP by assessing the equipment’s conducted immunity. It simulates the highly energetic, oscillating currents and voltages that are induced onto the external cables and power leads of the equipment after the EMP field interacts with the larger platform (e.g., an aircraft or vehicle). These induced currents take the form of damped sinusoidal transients.

Expert Electromagnetic Pulse Compliance Testing Laboratory

Known as one of the best EMP test labs in the country, Applus+ Keystone has extensive experience with shielding effectiveness and EMP testing. We work with manufacturers and citizens to determine if their equipment and shielding can handle natural or man-made EMPs. Contact us to determine how we can help you determine your product’s ability to survive an EMP event.

By partnering with Applus+ Keystone, you gain a deep understanding of your product’s electromagnetic resilience. Our services include custom test plan development and specialized chamber testing to ensure certifiable compliance and enhanced operational security against both conventional and nuclear-origin EMP threats. Request a free quote today!