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National Institute of Justice Standards: What Do the NIJ Protection Levels Mean?

When you step into the line of fire to do your duty, you want to know that you have the proper gear for the application. The National Institute of Justice (NIJ) provides scientific research and development for the United States Department of Justice (DOJ). This government agency sets the voluntary national standard for ballistically certified body armor worn by law enforcement and corrections officers.

The NIJ also provides commercial testing to evaluate armor for compliance with its performance standards. The test evaluates whether or not a bullet perforates the vest and the vest’s ability to protect the wearer against blunt force trauma.

The British, Australian and German governments have set international standards that provide criteria for body armor durability as well. Defenshield has created this overview to help you assess which body armor level is appropriate for the dangers you may encounter in the field.

Protection Levels and Types of Ammunition Explained

The NIJ provides five armor protection level classifications — IIA, II, IIIA, III and IV. The “A” in some levels refers to the fact that the vest offers more protection than the level before but cannot meet the standard of the next level, so it’s generally a half-step up. Although there is an armor level one, it’s now outdated and no longer approved by the NIJ because of its weak resistance level.

Soft body armor is typically level IIIA and below, while hard body armor is generally level III and up with body armor plates included. Each of the five armor levels has distinct advantages against different types of ammunition:

Other Types of Bullet-Resistant Ratings and Standards

A number of other standards exist for bullet-resistant armor. In addition to NIJ armor, the U.S. has standards from the State Department. Countries around the world and independent testing organizations have also produced their own standards, some of which include:

Find NIJ Ballistically Certified Armor from Defenshield Today

Defenshield is a global industry authority focused on the engineering and production of the highest quality ballistic protective equipment and tactical gear. Our clients include the U.S. government and military, law enforcement and foreign partners.

Defenshield has a guide to national and international armor standards you can browse for more information. If you have questions or want to make a purchase, reach out to our sales team online, call us at 904-679-3942 or send us an email at