Tactical Helmets: Testing & Ballistic Protection Levels

February 03, 2021

The standards that define a tactical helmet you can trust with your life

Whether you are in law enforcement, the military, or private security, knowing you’re well-protected provides vital confidence in dangerous situations. And a range of tactical helmet safety standards provide the essential benchmarks for head protection.

But which standards mean what—and how do you know which product can be trusted with your life?

This blog decodes the alphabet soup of safety standards for ballistic helmets, explaining which ones apply, who creates them, and what ballistic protection levels mean. We also dig into the extensive testing that should be conducted to ensure performance in challenging conditions.

Law enforcement and the military face alarming head injury risk

Serving in law enforcement and the military can be a dangerous profession, and the threat of gun-related injuries and fatalities looms particularly large.

The FBI reports that about half of U.S. police officers killed in the line of duty in 2019 were shot, including more than 91% of officers who were killed feloniously that year. Handguns accounted for nearly 80% of these deaths.

Head-strike hazards are another significant risk for police officers and security forces, leading to injuries caused by impact weapons, thrown projectiles, and more.

Researchers examined the FBI’s Law Enforcement Officers Killed and Assaulted database, data from the National Electronic Injury Surveillance System, and a range of studies to determine the impact and risk of brain injuries in law enforcement. They found “Elevated levels of head injury … in U.S. police forces relative to other blue light occupations (i.e. firefighters and emergency medical staff)” and note “police are likely to have an increased risk of injury due to the very dynamic situations that they are exposed to.”

Head injuries are an even more significant risk among military personnel, with closed head injuries considered the “signature wound” of the wars in Iraq and Afghanistan.

U.S. service members suffered nearly 414,000 TBIs between 2000 and 2019, according to The Defense and Veterans Brain Injury Center (DVBIC). Often regarded as an “invisible wound” among veterans, traumatic brain injury (TBI) can lead to long-term mental and physical problems.

On the battlefield, the biggest head injury threats boil down to the three Bs: ballistic, blunt, and blast. Soldiers face fragmentation and ballistic threats from artillery, explosions, and small arms fire; blunt trauma caused by falls, vehicle crashes, impact with vehicle interiors, translation from blasts, and parachute drops; and exposure to primary blasts.

As a result, tactical helmet manufacturers face a tall order. They must meet the seemingly opposing requirements of creating helmets that are comfortable, lightweight, and allow for a full range of head motion while also offering a high degree of mission-ready protection.

Today’s headgear is substantially lighter than previous generations, which can make all the difference between cursing every step and staying focused on your task. But lighter weight can also come with a trade-off: less protection.

Generally, lighter helmets can achieve a similar resistance to penetration as their heavier counterparts, but protection against “backface deformation” and “blunt impact” may decline. Backface deformation happens when a helmet defeats a projectile but deforms inward, potentially causing localized blunt impacts to the head.

However, a lot more goes into testing, designing, and manufacturing helmets that are comfortable, versatile, and offer adequate protection. Weighing critical factors like different safety standards, usability, and potential threats will help you choose the tactical helmet that’s right for you.

A good place to start is the National Institute of Justice (NIJ), which sets standards for body armor, ballistic-resistant materials, and, to a lesser extent, helmets.

NIJ body armor and tactical helmet standards: what’s the deal?

The National Institute of Justice sets crucial industry benchmarks for ballistic protective materials and body armor, but how these rules apply to tactical helmets is complicated—and can be misleading.

Commercially available protective equipment is tested and certified according to standards set by NIJ. As the research, development, and evaluation agency of the U.S. Department of Justice, the organization oversees performance standards for equipment used by criminal justice agencies. NIJ isn’t a regulatory body; its performance standards are voluntary. Manufacturers engage third-party labs to test their goods to the specs set by the standards, thus allowing them to promote a certain NIJ protective “level.”

NIJ guidance has become the industry standard for most commercially available body armor, largely adopted by manufacturers because it reflects best practices. It also makes it easier to compare equipment against a common set of benchmarks. But while NIJ maintains a tested Compliant Armor List, tactical helmets are governed by constantly evolving standards that defy one set of performance specifications. 

Today, ballistic helmets are commonly promoted as NIJ III-A, which basically means they protect against specific handgun threats. As we’ll get into shortly, however, what those exact threats are isn’t always clear, meaning an “NIJ III-A” label could mean slightly different things.

Before we explain that, we’ll need to go over three essential NIJ standards:

1. NIJ Standard 0106.01, Standard for Ballistic Helmets

An official NIJ helmet standard exists, but the document—Standard 0106.01—was published in 1981 and is considered woefully outdated. Further, 0106.01 “only consists of three levels, levels I, IIA and II, and so there is no level IIIa associated with an NIJ standard for helmets.” Clearly, today’s manufacturers aren’t testing to this old document.

2. NIJ Standard 0101.06, Ballistic Resistance of Body Armor

For now, body armor is tested to NIJ Standard 0101.06, Ballistic Resistance of Body Armor, which was published in 2008. This standard’s test protocol identifies five ballistic protection levels determined by the caliber and velocity that enable a bullet to puncture ballistic material and/or cause blunt trauma to the wearer:

NIJ body armor protection levels

Publication of the seventh revision of the body armor performance standard is expected in early 2021.

3. NIJ Standard 0108.01, Ballistic Resistant Protective Materials

The protection levels outlined by NIJ's Ballistic Resistant Protective Materials Standard (0108.01) can apply to a range of items. These levels define the ballistic resistance of any piece of equipment, including helmets:

NIJ ballistic materials protection levels graphic

So, when a helmet company advertises “Level IIIA protection,” which standard are they following?

Tactical helmet standards clarified: what does “NIJ Level IIIA” protection really mean?

There is currently no go-to NIJ list for compliant helmets, making it critical for military and law enforcement buyers to conduct a little more research.

When it comes to helmets advertised as “NIJ Level IIIA,” a manufacturer should be testing against NIJ Standard 0108.01, Ballistic Resistant Protective Materials. But some could conceivably be testing against the body armor standard.

Level IIIA protection according to 0108.01 ideally means that a helmet is tested to stop up to the following threats:

  • 240 grain .44 Magnum rounds at a nominal velocity of 1,400 f/s.
  • 124 grain 9 mm Full Metal Jacket (FMJ) rounds at a nominal velocity of 1,400 f/s.

So, a level IIIA helmet can stop a .44 Magnum, right?

Not so fast.

In reality, a lot of helmets aren't even tested to the .44 Magnum "IIIA" threat—very frequently, those that claim IIIA according to 0108.01 were only tested vs. the 9mm "IIIA" threat. In other words, helmet manufacturers don't always evaluate their stuff against both projectiles. 

In addition, there is some debate about whether helmets that are tested to stop a .44 Magnum would fully protect the wearer. The backface deformation injury from a .44 strike might still be fatal. 

Hard Head Veterans ballistic helmets are tested to protect against both calibers according to NIJ 0108.01, offering our customers more confidence in a quality product. When we say NIJ IIIA, we mean it. And our helmets protect against penetration from a .44 Magnum.

But as a general rule: all helmet purchasers and wearers should assume that a level IIIA helmet truly protects them against 9 mm Full Metal Jacket (FMJ) rounds at a nominal velocity of 1,400 f/s. And unless a manufacturer provides test data showing they’ve evaluated the .44 Magnum, purchasers should not assume they will have that level of protection.

Helmet standards are a little confusing, right?

Well, we’re not done yet. Helmets are also tested according to the specifications of other standards.

Beyond NIJ Level IIIA protection: enhanced combat helmets and additional standards

To keep up with the latest threats and make helmets from lighter, stronger materials, tactical helmet manufacturers also test to specific standards set by large contracts like the U.S. Army’s Advanced Combat Helmet Generation II (ACH GEN II).

For instance, ACH Blunt Impact Protection requirements (per Purchase Description AR/PD 10-02) stem from a widely used U.S. Army helmet impact test based on the Department of Transportation’s FMVSS (Federal Motor Vehicle Safety Standard) 218 for motorcycle helmets. And European countries often have their own ballistic helmet testing requirements that are also set by specific contracts.

By choosing ballistic helmets that meet NIJ Level IIIA and meet or exceed the latest large-contract standards, buyers can feel confident about making a high-quality purchase. Achieving these specs indicates a helmet has passed a string of strenuous tests included in NIJ’s Ballistic Resistant Protective Materials standard (108.01), and specific evaluations required by the MIL-STD 662F or NATO STANAG 2920 standards.

MICH helmet

This MICH/ECH HHV BTE® Ballistic Helmet paired with Up-Armor Plates offers a true solution to defeating the common rifle rounds, including 5.56 & 7.62mm mild steel core rifle ammunition.

Enhanced combat helmet (ECH) designs aim to take protection to the next level with greater safeguards against impacts and add-on plates that can stop certain rifle projectiles. Evolving research is also continually evaluating new materials that will balance the need for increased protection at less weight.

For instance, Hard Head Veterans’ MICH/ECH HHV BTE® Ballistic Helmet delivers the essential NIJ Level IIIA protection against handguns as well as lesser projectile threats. But it is also tested to meet the overall impact performance standards set out by the Advanced Combat Helmet contract and exceeds the ACH’s blunt impact protection requirements.

In addition, both Hard Head Veterans’ MICH/ECH HHV BTE® and ATE® GEN2 Ballistic Helmet can be mounted with Rifle-Rated Up-Armor Plates to meet the most common rifle threats head-on, including 5.56 M855 62 gr. and 7.62X39 Russian MSC steel penetrating rounds at full velocities.

Always look closely at an ECH helmet’s testing data before you buy.

While many manufacturers claim to offer ECH helmets in a monolithic design that can defeat rifle threats, digging into their data reveals that they are truly only “bulletproof” for particular rifle rounds at reduced velocities. Only the addition of adequately tested Up-Armor plates makes a helmet a real solution to head-on rifle threats.

We are often asked why ballistic helmets with added plates aren’t rifle-rated at NIJ Level IV to stop 30-06 steel core armor-piercing rifle ammunition—and trust us, we want that, too! Unfortunately, at this point, the materials needed to achieve that level of protection add another 7–9 lbs., rendering a helmet far too heavy.

Ensuring tactical ballistic helmet performance: the critical tests

While the ability to stop projectiles is vital, it’s not the only factor determining whether you can trust a tactical helmet. Again, helmets meant for U.S. troops face a series of rigorous laboratory tests before contracts are ever awarded.

Reputable manufacturers of commercially available helmets use the same tests that meet NIJ's safety standards and these large military contracts to assure quality gear. Buyers should beware of companies that don’t have readily available lab reports that prove protections met or exceeded the established baselines.

While in-house, random batch testing may also be conducted for quality assurance, these four tests are the most critical to safety—and therefore best performed at third-party, NIJ-certified labs:

1. Resistance to Penetration (RTP)

There’s no room for error in an RTP test, also known as “V0 testing,” which mandates a strict pass/fail stance against bullet perforation. It is measured as a sequence of five ballistic impacts: to the front, rear, left, right, and crown of a tactical helmet that’s placed on a clay headform.

To achieve NIJ Level IIIA protection, the test is typically performed using 9 mm, .357 Magnum, and .44 Magnum rounds. Zero perforations are permitted to meet NIJ Level IIIA standards as defined by 0108.01 and the modified 0106.01.

2. Backface Deformation or Ballistic Transient Deformation (BTD)

Helmet backface deformation can be easily assessed by measuring non-perforating ballistic impacts after RTP testing since it is determined using the same sequence of five shots. If the maximum impact depression depth in the clay headform caused by helmet deformation exceeds BTD limits, the helmet fails the test.

Here’s an overview of how it works:

  1. A tactical ballistic helmet is mounted on a clay headform that is then mounted in the test fixture.
  2. The helmet is removed from the headform so a laser can scan the clay surface.
  3. The helmet is reattached to the headform and fired upon.
  4. The helmet is once again removed from the headform and inspected for penetrations and deformations.
  5. The clay is rescanned with the laser to calculate backface deformation.

BTD tests are a debated topic, as the U.S. National Research Council has formally stated there is no scientific basis for BTD limits. But to meet ACH contract specifications, the U.S. military requires BTD averages under 25.4 mm for front and back shots and 16 mm for side and crown shots using a 9mm FMJ projectile.

Backface deformation

BTD tests measure the potential of backface deformation (demonstrated in this steel plate) to cause localized blunt impacts after stopping bullets.

3. Fragmentation Performance

In modern combat environments, fragments and shrapnel pose a greater threat of injury or death than bullets. The Defense Technical Information Center (DTIC) reports that as many as 80% of combat injuries are caused by fragments from explosive munitions like shells or grenades. The interest in fragmentation performance is also rising among law enforcement agencies, especially riot and SWAT teams.

A V50 test is an internationally recognized standard for assessing the fragmentation resistance of personal protection equipment. It reveals a tactical helmet’s breaking point by firing fragment simulating projectiles (FSPs) at higher and higher velocities until they start penetrating.

The V50 value reflects the velocity at which 50% of the shots penetrate the helmet, and 50% are stopped. The greater the V50 value, the greater the protection.

The most widely used standards for testing fragment resistance for a ballistic helmet are MIL-STD 662F and NATO’s STANAG 2920, which require a minimum V50 of 1470 f/s (450m/s) or V50 2130 f/s (650m/s), depending upon the weight and type of fragment projectile.

ACH GEN II contract specifications require a minimum V50 of 2,200 f/s (670 m/s) for 22-caliber 17 grain FSPs.

Explosion on a battlefield

Fragments from explosive munitions are a more common threat than bullets on the modern battlefield.

Here’s an overview of how V50 tests work based on MIL-STD 662F protocols:

  • A tactical ballistic helmet is mounted to a headform with a 2024-T3 Alum witness plate.
  • Testers fire at the helmet, typically starting with a high velocity and then decreasing powder charge and velocities to produce complete, partial, and no penetrations. MIL-STD 662F instructs testers to deliver first-round shots with a striking velocity about 75 to 100 f/s above the minimum V50 required. Starting velocities can also be set by previous V50 testing on comparable helmets.
  • If the first round causes a complete penetration, the second round's velocity is decreased by 50 to 100 f/s. If there is no penetration, the velocity is increased by the same amount.
  • For the rest of the test, the velocity is increased or decreased as needed until one partial and one complete penetration is obtained.
  • Once that occurs, the velocity is increased or decreased in increments of 50 f/s. Firing continues until enough partial and complete penetrations are obtained to estimate V50. This is done by calculating the average velocity corresponding to an equal number of the highest partial and lowest complete penetrations.

The military standard does not mandate a maximum number of shots for the test, but between 8 and 14 are typically used. STANAG 2920 requires an even number of at least six shots—half perforating and half not—with velocities of 40 m/s (131 f/s) or less. The V50 is then estimated as the mean velocity of the three lowest complete penetrations and the three highest partial penetrations.

Parachute jump with helmet

Tactical ballistic helmets are tested to ensure peak accelerations of 150 Gs or less, so they don't transmit excessive force to wearers who hit their heads during impacts.

4. Blunt Impact Performance

Blunt impact testing measures a tactical helmet’s performance against realistic blunt impact threats like falls, motor vehicle crashes, and parachute drops.

The ACH GEN II contract’s blunt impact protection requirements utilize a widely used U.S. Army helmet impact test derived from the Department of Transportation’s (DOT) FMVSS (Federal Motor Vehicle Safety Standard) 218 for motorcycle helmets.

ACH specifications require multiple drops with peak accelerations remaining at 150 Gs or less, so they don’t transmit excessive force to wearers who hit their heads.

Here’s an overview of how the test works:

  1. The tactical helmet is fitted onto a DOT headform and positioned on a monorail drop tower.
  2. The helmet is dropped onto a hemispherical steel anvil at different impact sites—two times each for the crown, front, back, right lateral, left lateral, right nape, and left nape.
  3. During each impact, acceleration is measured to ensure it stays at 150 Gs or less.

More critical tests for tactical helmets

To ensure performance, tactical helmet testing is repeated at ambient, hot, and cold temperatures and after immersing helmets in saltwater to gauge performance in different environments.

While head injuries resulting from tactical helmet compressions are rare, today’s lighter materials have also led to concerns about helmet stiffness. Compression tests are other essential safety criteria, ensuring permanent deformations that compromise performance won't result from everyday use.

Compression tests measure deformations to tactical helmets after multiple compressions are applied to all sides. According to ACH contract specifications, pass/fail numbers must not exceed .020” (0.51mm) shape deformation within five minutes.

Watch this video to see Hard Head Veterans helmets go through all these vital tests:

Do your homework and buy tactical helmets with essential impact, fragmentation, and ballistic protection

A helmet’s listed features and prices mean nothing if it doesn’t meet essential safety standards. But without a simple, straightforward list of compliant helmets from a trusted source like NIJ, it’s up to buyers to do their homework and demand test results that prove the highest levels of safety.

At a minimum, ensure that a ballistic helmet is classified to meet NIJ Level IIIA—and review testing data to define whether this includes a .44 Magnum evaluation. But also look beyond this protection level. For example, Hard Head Veterans’ MICH/ECH HHV BTE® Ballistic Helmet also offers impact, fragmentation, and blunt impact performance that meet or exceed advanced combat helmet standards.

Knowing these critical safety measures are met—with the lab tests to back it up—is vital to selecting a tactical ballistic helmet you can trust with your life.

Hard Head Veterans stays on top of helmet research to ensure we provide the best protection possible. Read more blog posts and be sure to check out our gear, including a selection of the best tactical helmets and essential helmet accessories.




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