NIJ Ballistic Protection Levels

What the NIJ standard is

The National Institute of Justice (NIJ), the research agency of the U.S. Department of Justice, publishes performance standards for ballistic-resistant body armor worn by law enforcement officers. NIJ Standard-0101.06, published in 2008, defines five protection levels and the laboratory method used to test them. Although it was written for U.S. police, it is one of the most widely referenced body armor standards in the world and appears in many military and security tenders.

Every level is defined by specific test rounds fired at a specified velocity. Armor passes when none of the rounds perforate it and the dent left in the clay backing material behind the armor (back-face deformation) stays within 44 mm. Soft armor is tested both new and after conditioning, a process of tumbling at raised temperature and humidity that simulates wear.

NIJ 0101.06 levels at a glance

The table lists the test rounds and reference velocities for new armor. Conditioned soft armor is tested at slightly lower velocities.

Levels IIA, II and IIIA are normally met with flexible panels made of aramid or UHMWPE fabric layers. Levels III and IV require hard plates made of UHMWPE, ceramic and composite, or steel, carried in a vest either on their own or over a soft panel.

Each level is tested only against its own listed rounds. Higher levels generally cover the threats of lower levels, but the only reliable way to know whether an armor stops a particular round is the test report.

Stand-alone and in-conjunction plates

A plate rated "stand-alone" passed the test on its own. An "in-conjunction" plate passed only when a specified soft armor panel was placed behind it, so its rating is valid for that combination only. When you compare offers for rifle plates, check which configuration the stated level refers to.

What does "Level III+" mean?

III+ is not a level defined in NIJ 0101.06. The industry uses the term for plates that meet Level III and were additionally tested against selected rifle rounds, for example 5.56 mm M193 or M855, or 7.62×39 mm mild steel core. Because there is no common definition, a III+ plate should always be judged by a test report that lists the exact rounds and velocities. İpek's HardPlate III+ is listed under this designation; you can ask us for its test documentation.

NIJ 0101.07 and NIJ 0123.00: the new designations

In November 2023 NIJ published Standard 0101.07 together with NIJ Standard 0123.00, the "Specification for NIJ Ballistic Protection Levels and Associated Test Threats". 0101.07 now describes how armor is tested, while 0123.00 defines the protection levels and their test rounds. The Roman numerals were replaced by HG (handgun) and RF (rifle) levels.

Level IIA has no equivalent in the new specification. The biggest practical change concerns rifle plates: RF1 adds two common rifle rounds that a Level III plate was never required to stop, and RF2 adds the M855 round on top of that.

Armor certified to NIJ 0101.06 remains in use, and NIJ has said it will keep the 0101.06 compliant products list through at least the end of 2029. For the next few years both naming systems will therefore appear side by side in specifications and tenders.

How to read an NIJ rating on an offer

• Edition and level: is the rating based on NIJ 0101.06 or on NIJ 0101.07 with 0123.00?
• Configuration: stand-alone plate, or in conjunction with a named soft panel?
• Evidence: which laboratory tested the model, and is the test report available for the size you are buying?
• Coverage: the size and cut of the tested panel or plate, which determine how much of the body is protected.
• Additional threats: any rounds tested beyond the standard list, for example for III+ plates.
• Weight: the level says nothing about comfort, so compare weight per size as well.

Levels shown on İpek product pages are the levels stated in our product data. Ballistic helmets are not covered by NIJ 0101.06 as body armor; they are commonly specified against Level IIIA handgun rounds, and the test method used should be named in the helmet's test report. Our ballistic helmet guide explains the helmet types.