Body Armor 101: How to Choose

To better understand the choices, let’s go step by step through the various types of armor, threat levels, and certification processes.


There are tons of body armor options out there for departments and individual first responders to choose among. From soft inserts to ceramic plates to carriers, which ones are right for your needs? To better understand the choices, let’s go step by step through the various types of armor, threat levels, and certification processes.

Types of Armor

The two most common types of armor are “soft armor” and “hard armor.” Soft armor is commonly found in concealable armor, the types of vests worn underneath a uniform shirt. Soft body armor does not deflect or repel bullets. Instead, it catches the bullet within the weave to dissipate the energy and prevent it from penetrating. The panels are made of either tightly woven aramid threads, such as Kevlar or other similar material, laminates such as Dyneema, or a combination of these fabrics.

Hard armor is harder and thicker, typically made from either steel or ceramic, and usually backed with pressed laminate. Each has its advantages and drawbacks. Hard armor is designed to shatter the round, dispersing the energy and preventing penetration. Many armor plates have an extra layer on the outside to reduce fragmenting and minimize the chance of injury.

While soft armor tends to be fairly lightweight and suitable for everyday wear, hard armor is heavier, so it is reserved largely for tactical vests and any application where the wearer will have it on for a relatively short time.

Threat Levels

Body armor, both soft and hard, is designed to stop only certain types and calibers of bullets.

The National Institute of Justice (NIJ) sets the standards for “threat level,” the measure of stopping power based on the caliber and velocity of the projectile.

Threat levels fall into five categories: IIA, II, IIIA, III, and IV. Each higher category protects against higher-level threats than the previous one.

Concealable soft armor typically rates to level II or IIIA, designed to stop pistol rounds. Hard armor plates rate as high as IV, tested to stop certain types of armor-piercing rifle ammunition.

NIJ-Certified vs. NIJ-Compliant

Not all armor is created equal. The NIJ not only sets ballistic armor standards, it also runs a comprehensive testing program and encourages manufacturers to submit their armor panels, both soft and hard, for testing at their facilities. The test includes not only ballistics tests to determine threat level, but also endurance tests, such as immersing the armor in water for 30 minutes and a high-humidity/high-heat test to see how well the fibers hold together under adverse conditions. Armor that passes official NIJ laboratory testing is labeled as “NIJ-certified,” the highest rating that armor can achieve. Because it is so thorough, NIJ testing is a long and expensive process.

To save money, sometimes manufacturers opt to make armor that satisfies the NIJ written standard but is not actually tested by the NIJ. This armor is label “NIJ-compliant.”

While this armor may stop bullets just as well as NIJ-certified armor, the NIJ cannot verify that the armor will perform as claimed. Propper only sells NIJ-certified armor.


Factors that Impact Armor Effectiveness

While body armor is rugged and durable, it is not impenetrable under all conditions. Several factors determine how well it works beyond just its design.

  • Moisture – Water can wreak havoc on soft armor, which relies on a tight weave to stop bullets. As the fibers get wet, they begin to relax, spread apart, and weaken the overall structure of the weave, allowing gaps in coverage. This is why soft armor is housed in a waterproof carrier that repels moisture. If the waterproof seal is broken, moisture may work its way inside and weaken the weave.
  • Multiple Hits – While NIJ standards do rate for multiple hits across the face of a vest, most armor is designed to take only one, maybe two shots in a single area. Depending on how close together they are, multiple hits can compromise the integrity of the armor, both soft and hard, as the bullets begin to tear into the structure designed to withstand the impact of only one hit at a time. The first strike compromises fiber or plate strength and weakens the spot, lessening the stopping power if subsequent shots hit the same area. The odds of that occurring are low, but it can happen.
  • Coverage – Put simply, a vest can’t stop a bullet from hitting something that’s not covered. The wider the ballistic material, the better chance the bullet will hit it. Be sure any gaps in your vest are closed. This is especially important in two-panel clamshell vests that can leave areas of vulnerability on the sides if not sized correctly.
  • Wear and Tear – Armor doesn’t last forever. The materials, especially in soft armor, break down over time and can accelerate depending on conditions. For this reason, the NIJ recommends inspecting in-use body armor at least once a year.

Ceramic vs. Steel vs. Polyethylene

Hard plates are made from three basic materials: steel, ceramic, polyethylene, or combinations of materials. All are highly effective. Choosing among them comes down to a question of cost vs. weight.

Steel plates are heavier than ceramic but also less expensive. They are less susceptible to multi-hit issues, as any unhit areas remain intact and stop additional rounds striking the plate. However, the spall that occurs from impact can send fragments in all directions and can injure the wearer or individuals who are in close proximity.

For this reason, we do not recommend steel plates to our customers. We always recommend other types of hard armor.

Ceramic plates cost a bit more but offer a significant weight savings. This is especially beneficial when carrying lots of other gear, such as extra magazines, a radio, and other equipment often strapped to a plate carrier. Ceramic plates have excellent stopping power. The main drawback to ceramic is its susceptibility to damage not just from bullets but from everyday activity such as dropping it into the trunk of a patrol car.

Polyethylene is a lightweight, plastic-type substance that stops the bullet by using the bullet’s own friction to partially melt the plate and then instantly cool it to wrap the bullet inside, both stopping it from penetrating and reducing bounce and fragmentation. The biggest downside to polyethylene is a lack of level IV protection. It is also somewhat expensive when compared to other types of hard armor.

Which to Choose

Patrol officers and others who wear armor on a regular basis, for hours at a time, often prefer concealable soft armor due to its relatively light weight compared to hard plate armor and slim profile that hides better under a uniform.

SWAT and other tactical teams are less concerned about concealability and more about maximum protection, so they often complement the soft armor with a plate carrier full of higher level stopping power.

Correct Fit

Whichever armor you choose, it needs to fit right to work right. One of the biggest complaints about body armor in general is it’s uncomfortable because it’s either bulky or doesn’t fit correctly. Ill-fitting armor can hinder the mission, or worse, get left at the station or trunk when it needs to be protecting the officer.

Correct-fitting armor encourages officers to wear it, increasing the odds they will go home at the end of the shift.

As you consider your armor needs, think less about cost and more about how it will be used.