Standard for testing and protection grades of tactical helmets
Nov 06, 2020
Whether you're in law enforcement, the military, or private security, knowing you're well-protected provides vital confidence in dangerous situations. A series of tactical helmet safety standards provide the basic benchmark for head protection.
But what standards mean - how do you know which products you can trust?
Head Injury Risks to Law Enforcement and the Military
Serving in law enforcement and the military can be a dangerous career, and the threat of firearm-related injury and death is especially high.
About half of U.S. police officers killed in the line of duty in 2019 were shot and killed, and more than 91 percent of those officers were killed by felonies that year, the FBI reported. Handguns account for nearly 80 percent of those deaths.
Head impact hazard is another significant risk to police and security forces, resulting in injuries such as striking weapons, throwing projectiles, and more.
The researchers examined the FBI's database of law enforcement killings and assaults, data from the National Electronic Injury Surveillance System, and a range of studies to determine the impact and risk of brain injury in law enforcement. They found "higher levels of head injuries in U.S. police forces compared to other blue light occupations (i.e. firefighters and emergency medical personnel)," noting that "due to the dynamic situation in which police officers are exposed, they may be at increased risk of injury exposure ."
Head injuries are a greater risk for military personnel, and closed head injuries are considered the "signature wound" of the wars in Iraq and Afghanistan.
According to the Defense and Veterans Brain Injury Center (DVBIC), U.S. military personnel suffered nearly 414,000 TBIs between 2000 and 2019. Often seen as a "hidden wound" for veterans, traumatic brain injury (TBI) can lead to long-term mental and physical problems.
On the battlefield, the greatest threat of head injury boils down to the three Bs: ballistic, blunt and explosive. Soldiers face fragmentation and ballistic threats from artillery, explosive, and small arms fire; blunt trauma from falls, vehicle collisions, collisions with vehicle interiors, explosions, and parachute falls; and exposure to primary blasts.
As a result, tactical helmet manufacturers face a daunting task. They must meet the seemingly opposite requirements of creating a helmet that is comfortable, lightweight, allows for a full range of head movement, while also providing a high degree of mission-ready protection.
Today's helmets are much lighter than previous generations, which can make a huge difference between executing each step and focusing on your task. But lighter weight also comes with a tradeoff: less protection.
In general, lighter helmets can achieve similar penetration resistance as heavier helmets, but protection against "backward deformation" and "bludgeoning" may be reduced. Backward deformation occurs when the helmet smashes the projectile but deforms inward, potentially causing a localized bludgeoning blow to the head.
However, there is still a lot of work to be done in testing, designing and building helmets that are comfortable, versatile and provide adequate protection. Weighing key factors such as different safety standards, usability and potential threats will help you choose the right tactical helmet for you.
A good place to start is the National Institute of Justice (NIJ), which sets the standard for body armor, ballistic materials and, to a lesser extent, helmets.
NIJ Standard for Body Armor and Tactical Helmet: What is it?
The National Institute of Justice sets key industry benchmarks for ballistic protection materials and body armor, but how those rules apply to tactical helmets is complex and potentially misleading.
Commercially available protective equipment is tested and certified according to the standards established by the 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 is not a regulatory agency; its performance standards are voluntary. Manufacturers hire third-party laboratories to test their products for compliance with the specifications set forth in the standard, allowing them to increase a certain "level" of NIJ protection.
The NIJ guidelines have become the industry standard for most commercially available body armor and are widely adopted by manufacturers because it reflects best practice. It also makes it easier to compare devices against a common set of benchmarks. But while the NIJ maintains a list of tested and compliant armors, tactical helmets are subject to evolving standards that violate a set of performance specifications.
Today, ballistic helmets are often referred to as NIJ III-A, which basically means they protect against a specific pistol threat. However, as we'll discuss shortly, these exact threats aren't always clear, meaning the "NIJ III-A" label could mean something slightly different.
Before we explain, we need to understand three basic NIJ standards:
1. NIJ Standard 0106.01, Ballistic Helmet Standard
An official NIJ helmet standard exists, but this document - Standard 0106.01 - was published in 1981 and is considered outdated. Additionally, 0106.01 "contains only three classes, I, IIA, and II, so there is no class IIIa associated with the NIJ helmet standard." Clearly, today's manufacturers did not test this old document.
2. NIJ Standard 0101.06, Ballistic Resistance of Body Armor
Currently, body armor has been tested according to NIJ Standard 0101.06, Ballistic Resistance of Body Armor, published in 2008. The standard's testing protocol identifies five ballistic resistance levels, determined by the bullet's ability to pierce ballistic materials and/or cause blunt trauma to the wearer:
NIJ body armor protection rating
The seventh edition of the Body Armor Performance Standard is expected to be released in early 2021.
3. NIJ Standard 0108.01, Ballistic Protective Materials
The degrees of protection outlined in the NIJ's Standard for Ballistic Protective Materials (0108.01) apply to a range of items. These levels define the ballistic resistance of any equipment, including helmets:
NIJ Ballistic Material Protection Class Diagram
So, when a helmet company advertises "Class IIIA protection," what standards do they follow?
Tactical Helmet Standard Clarification: What Does "NIJ Class IIIA" Protection Really Mean?
There is currently no NIJ listing for compliant helmets, making it critical for military and law enforcement buyers to do more research.
For helmets advertised as "NIJ Level IIIA", manufacturers should test in accordance with NIJ Standard 0108.01 (Ballistic Protection Materials). But conceivably some are testing against body armor standards.
Ideally, Level IIIA protection according to 0108.01 means helmets are tested to block the following threats:
240-grain .44 Magnum with a nominal speed of 1,400 f/s.
124 grain 9mm full metal casing (FMJ) rounds with a nominal speed of 1,400 f/s.
So, a Class IIIA helmet can block 0.44 Magnum, right?
Not so fast.
In fact, many helmets are not even tested against the 0.44 Magnum "IIIA" threat - often, those that claim to be IIIA under 0108.01 are only tested against the 9mm "IIIA" threat. In other words, helmet makers don't always evaluate their stuff against both projectiles.
Additionally, there is some debate as to whether helmets tested to block 0.44 Magnum fully protect the wearer. Backward deformation damage from 0.44 impact may still be lethal.
Tophelmetfan ballistic helmets are tested against two calibers according to NIJ 0108.01, giving our customers more confidence in a quality product. When we say NIJ IIIA, we mean it. Our helmets prevent penetration of 0.44 Magnum.
But as a general rule: all helmet buyers and wearers should assume that a Class IIIA helmet actually protects them from a 9mm full metal jacket (FMJ) bullet rated at 1,400 f/s. Buyers should not assume they will have that level of protection unless the manufacturer provides test data indicating that they have evaluated the .44 Magnum.
Helmet standards are a bit 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 Helmet and Other Standards
To keep up with the latest threats and use lighter, stronger materials for helmets, tactical helmet manufacturers are also tested to specific standards set by large contracts such as the U.S. Army Advanced Combat Helmet 2nd Generation (ACH GEN II).
For example, the ACH Blunt Impact Protection requirement (per Procurement Note AR/PD 10-02) stems 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 motorcycles helmet. European countries often have their own ballistic helmet testing requirements, which are also specified by specific contracts.
By choosing ballistic helmets that meet NIJ Level IIIA and meet or exceed the latest big contract standards, buyers can be confident in making a quality purchase. Achieving these specifications indicates that the helmet has passed the rigorous series of tests contained in the NIJ's Standard for Ballistic Protective Materials (108.01), as well as specific evaluations required by MIL-STD 662F or NATO STANAG 2920.
This MICH/ECH ballistic helmet paired with an armor plate offers a real solution to defeat common rifle rounds, including 5.56 and 7.62mm mild steel core rifle rounds.
The Enhanced Combat Helmet (ECH) is designed to take protection to the next level with stronger impact protection and additional plates that can stop certain rifle projectiles. Evolving research is also continually evaluating new materials that will balance the need for increased protection at a lighter weight.
For example, Tophelmetfan's MICH/ECH ballistic helmets provide the necessary NIJ IIIA protection against pistol and smaller projectile threats. But it has also been tested to meet the overall impact performance standards set by the Premium Combat Helmet Contract and exceeds the ACH requirements for blunt impact protection.
In addition, both Tophelmetfan's MICH/ECH and GEN2 ballistic helmets can be fitted with rifle-grade upper armor plates for head-on protection against the most common rifle threats, including the 5.56 M855 62 gr. and 7.62X39 Russian MSC full-speed armor-piercing rounds.
Be sure to carefully review the test data for ECH helmets before purchasing.
While many manufacturers claim to offer ECH helmets with a one-piece design that can defend against rifle threats, digging into their data shows that they are indeed "bulletproof" for low-velocity firing of specific rifle cartridges. Only the addition of the well-tested Up-Armor plate makes the helmet a true solution to the frontal threat of rifles.
We are often asked why ballistic helmets with add-on plates are not rated NIJ IV to stop the rifle rating of 30-06 steel core armor-piercing rifle ammunition - trust us, we want that too! Unfortunately, at this point, the material needed to achieve this level of protection adds another 7-9 pounds, making the helmet too heavy.
Ensuring the performance of tactical ballistic helmets: key tests
While the ability to stop projectiles is critical, it's not the only factor that determines whether you can trust a tactical helmet. Likewise, helmets designed for the U.S. military go through a rigorous series of lab tests before the contract is awarded.
Well-known commercial helmet manufacturers use the same tests that meet NIJ safety standards and these large military contracts to ensure gear quality. Buyers should be wary of companies that do not have readily available lab reports demonstrating that protection meets or exceeds established baselines.
While random batch testing can also be done in-house for quality assurance, these four tests are the most critical to safety—so best done in a third-party, NIJ-accredited laboratory:
1. Resistance to Penetration (RTP)
There is no room for error in the RTP test (also known as the "V0 test"), which requires a strict pass/fail stance on bullet piercing. It was measured as a sequence of five ballistic impacts: front, rear, left, right and top of a tactical helmet placed on a clay headform.
To achieve NIJ IIIA protection, testing is typically conducted with 9mm, 0.357 Magnum and 0.44 Magnum rounds. Allows zero perforation to NIJ Class IIIA as defined by 0108.01 and modified 0106.01.
2. Backward Deformation or Ballistic Transient Deformation (BTD)
Helmet back deformation can be easily assessed by measuring non-pierced ballistic impact after the RTP test, as it is determined using the same five-shot sequence. If the maximum impact dimple depth in the clay headform caused by helmet deformation exceeds the BTD limit, the helmet fails the test.
Here is an overview of how it works:
1.The tactical ballistic helmet was mounted on a clay headform and then in a test fixture.
2.The helmet is removed from the headform so the laser can scan the clay surface.
3.The helmet reconnects to the head shape and fires.
4.Remove the helmet from the headform again and check for penetration and deformation.
5.Rescan the clay with a laser to calculate the backside deformation.
BTD testing is a controversial topic because the US National Research Council has officially stated that BTD restrictions have no scientific basis. But to meet ACH contract specifications, the U.S. military requires a 9mm FMJ projectile with a BTD average of less than 25.4mm for frontal and rear fire, and a BTD average of 16mm for side and top fire.
The BTD test measures the potential for backside deformation (shown in this plate) to cause a localized bludgeoning blow after stopping the bullet.
3. Sharding performance
In the modern combat environment, fragments and shrapnel cause a greater threat of injury or death than bullets. The Defense Technical Information Center (DTIC) reports that up to 80 percent of combat injuries are caused by fragments of explosive ordnance such as shells or grenades. Interest in fragmented performance is also on the rise among law enforcement agencies, especially riot and SWAT teams.
The V50 test is an internationally recognized standard for evaluating the shatter resistance of personal protective equipment. It reveals the breaking point of tactical helmets by firing Fragmentation Simulating Projectiles (FSPs) at increasing velocities until they begin to penetrate.
The V50 value reflects 50% of the bullets penetrating the helmet and stopping 50% of the speed. The larger the V50 value, the greater the protection.
The most widely used standards for testing ballistic helmet fragment resistance 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 on Depending on the weight and type of fragmentation projectile.
The ACH GEN II contract specification requires a minimum V50 of 2,200 f/s (670 m/s) for a 22 caliber 17 grain FSP.
explosion on the battlefield
Fragments of explosive ordnance are more common than bullets on the modern battlefield.
The following is an overview of how V50 testing based on the MIL-STD 662F protocol works:
The tactical ballistic helmet is mounted on a headform with a 2024-T3 Alum witness plate.
Testers fired into the helmet, usually starting at high speed, then reducing the powder charge and velocity to produce full, partial, and no penetration. MIL-STD 662F instructs testers to deliver first-round shots at strike speeds of approximately 75 to 100 f/s above the required minimum V50. Startup speed can also be set via previous V50 testing on a similar helmet.
If the first round results in full penetration, the second round is slowed down by 50 to 100 f/s. If there is no penetration, the speed is increased by the same amount.
For the rest of the tests, increase or decrease the speed as needed until one partial penetration and one full penetration are obtained.
Once this happens, the speed increases or decreases in 50 f/s increments. Continue firing until sufficient partial and full penetration is obtained to estimate V50. This is done by calculating the average velocity corresponding to an equal number of the highest partial penetration and the lowest full penetration.
Military standards do not specify the maximum number of shots tested, but typically 8 to 14 shots are used. The STANAG 2920 requires an even number of at least 6 perforations—half perforations, half perforations—at 40 m/s (131 f/s) or less. The V50 was then estimated as the average velocity of the three lowest complete penetrations and the three highest partial penetrations.
skydiving with helmet
Tactical ballistic helmets are tested to ensure peak acceleration of 150 Gs or less, so they don't transmit excessive force to the wearer hitting their head on impact.
4. blunt performance
The blunt impact test measures the performance of tactical helmets against real-world blunt impact threats such as falls, motor vehicle collisions and parachute drops.
The blunt impact protection requirement of the ACH GEN II contract leverages the 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.
The ACH specification requires multiple drops and peak accelerations to be kept at 150 Gs or less, so they don't transmit excessive forces to the wearer striking the head.
Here is an overview of how the test works:
The tactical helmet is mounted on a DOT headform and placed on a monorail pendant.
The helmet lands on the hemispherical anvil in different impact positions - twice each on the top of the head, front, back, right, left, right and left neck.
During each impact, acceleration is measured to ensure it remains at 150 Gs or less.
More key tests for tactical helmets
To ensure performance, tactical helmet testing is repeated at ambient, high and low temperatures, and the helmet is dipped in salt water to measure performance in different environments.
While head injuries due to compression in tactical helmets are rare, today's lighter materials have also raised concerns about helmet stiffness. Compression testing is another important safety standard, ensuring that daily use does not cause permanent deformation that affects performance.
The compression test measures the deformation of a tactical helmet after multiple compressions on all sides. According to the ACH contract specification, the pass/fail number must not exceed 0.020” (0.51mm) of shape deformation within five minutes.
Do your homework and buy a tactical helmet with basic impact, fragmentation and ballistic protection
If the helmet does not meet basic safety standards, the features and price listed on the helmet will be meaningless. But without a simple, straightforward listing of compliant helmets from trusted sources like the NIJ, buyers must do their homework and ask for test results that demonstrate the highest level of safety.
At a minimum, make sure the ballistic helmet is classified to NIJ Class IIIA - and look at the test data to see if this includes the 0.44 Magnum assessment. But also go beyond this level of protection. For example, Tophelmetfan's MICH/ECH ballistic helmets also have impact, crush and bludgeoning performance that meets or exceeds the standards of advanced combat helmets.
Knowing that these key safety measures are met - backed up by lab testing - is critical to choosing a tactical ballistic helmet you can trust.
Tophelmetfan always pays attention to helmet research to ensure we provide the best protection. Read more blog posts and be sure to check out our gear, including our selection of the best tactical helmets and essential helmet accessories.