Ballistic Resistance of Body Armor, NIJ Standard 0101.07

This National Institute of Justice (NIJ) publication, Ballistic Resistance of Body Armor, NIJ Standard 0101.07, specifies minimum performance requirements and test methods for the ballistic resistance of body armor used by U.S. law enforcement that is intended to protect the torso against handgun and rifle ammunition. It is a revision of National Institute of Justice (NIJ) Standard 0101.06, Ballistic Resistance of Body Armor, published in 2008.[1]

The primary purpose of this standard will be for use by the NIJ Compliance Testing Program (CTP) for testing, evaluation, and certification of ballistic-resistant body armor. It will also be used by ballistic testing laboratories and body armor suppliers participating in the NIJ CTP. This standard will be included in the Law Enforcement and Corrections Equipment Laboratory Accreditation Program (LAP) of the National Voluntary Laboratory Accreditation Program (NVLAP) to accredit ballistics laboratories.[2]

NIJ Standard 0101.07 is divided into fourteen sections and eight appendices and differs from NIJ Standard 0101.06 in several important ways. Among these are notable structural changes between the two documents, as well as the introduction of several improvements to test methods and laboratory practices. An overview of these differences is provided in the following paragraphs.

Referencing a Suite of Standards

Unlike previous versions of the NIJ standard, NIJ Standard 0101.07 references a suite of standardized test methods and laboratory practices published by ASTM. NIJ, the U.S. Army, the National Institute of Standards and Technology (NIST), ballistics laboratories, body armor manufacturers, materials suppliers, and other stakeholders have been working collaboratively for several years within ASTM Committee E54 on Homeland Security Applications to harmonize, where possible, laboratory test procedures and practices relevant to ballistic testing. The result of this collaboration has been a suite of test methods and laboratory practices developed within ASTM Subcommittee E54.04 on Public Safety Equipment, many of which are referenced in this document.[3]

Incorporation of relevant ASTM standards into U.S. government standards and technical requirements affords the opportunity to harmonize laboratory test procedures and practices for both law enforcement and military ballistic-resistant armor and other ballistic-resistant equipment where the same general testing methodology otherwise applies. This also provides those end-user communities ultimate control over product specifications, such as the specific threats against which their equipment must protect.

Ballistic Threat Level Changes

The ballistic test threats are no longer listed in NIJ Standard 0101.07 as in past revisions of the standard. These have been moved into Specification for NIJ Ballistic Protection Levels and Associated Test Threats, NIJ Standard 0123.00, which is a new standalone document that defines ballistic threats identified by U.S. law enforcement as representative of current prevalent threats in the United States.

NIJ Standard 0123.00 was designed be used in conjunction with other standards like NIJ Standard 0101.07 to test and evaluate specific ballistic-resistant equipment, such as ballistic- resistant body armor, against contemporary ballistic threats that pose a life-threating safety hazard to U.S. law enforcement officers. The test projectiles and reference velocities in the inaugural version of NIJ Standard 0123.00 have been updated from section 2 of NIJ Standard 0101.06 to reflect the current threats faced by U.S. law enforcement end users, including a wider range of rifle threats.

Protection level nomenclature has also been moved into NIJ Standard 0123.00 and has been revised to be more descriptive of threats and to reduce confusion for users of body armor, see Table 1.

NIJ Standard 0101.07 references the new ballistic protection levels in the inaugural version of NIJ Standard 0123.00 rather than defining the levels within NIJ Standard 0101.07 itself, as was done in NIJ Standard 0101.06 and previous versions.

Improved Test Methods for Armor Designed for Women

Fourth, this standard contains improvements to the test methods for armor designed for women, including new clay appliques (e.g., build-up of clay) to ensure better contact of nonplanar panels with the clay backing material and new shot requirements to assess shaping features. Shot placement has also been reconfigured to exploit potential vulnerabilities due to unique construction elements in the panel and nonzero angles of incidence in the proximity of edges.

Earlier drafts of NIJ Standard 0101.07 initially referenced ASTM E3086, Standard Practice for Creating Appliques for Use in Testing of Nonplanar Soft Body Armor Designed for Females.

This ASTM standard specified a procedure for creating appliques for use behind nonplanar soft armor panels and affixing the appliques to the clay block. The purpose was to specify critical parameters for creating appliques in order to improve consistency of the test setup between laboratories. The practice described a single applique shape applicable only to nonplanar, soft body armor designed for women.

Implementation of this laboratory practice proved more challenging than expected, including difficulty creating the specific applique shapes described in ASTM E3086 and ensuring proper contact with the armor panel once mounted on the clay block. These challenges required reconsideration of how to build up clay behind nonplanar soft armor panels. A more simplified applique was developed to ensure that the panels are fully filled in with clay before mounting on the clay block. This applique is more monolithic in form and better supports armors designed for female wearers during testing. It is created using one of two standardized mold sizes along with a procedure to shape its form once affixed to the clay block. The result is a better substrate to ballistically test nonplanar armor, replacing the procedure in ASTM E3086. The electronic files containing the drawings of the molds to make the clay appliques described in Appendix G are freely available to NIJ-approved testing laboratories and other organizations upon request.

Updated Perforation-Backface Deformation Testing

NIJ has updated perforation-backface deformation (P-BFD) testing to include an additional shot on soft armor panels. How soft armor responds to handgun projectiles striking very near the top edge of a front armor panel has been explored by an adjacent U.S. Government agency through experimental testing efforts. This involved mounting a ballistic vest with soft armor panels in an external carrier onto a model female torso made of molded ballistic gelatin. In this configuration, the top of the panel is naturally slanted back toward the torso in the carrier, creating an angle of obliquity between the armor panel and the trajectory of the incoming bullet. Shots striking the top-center edge at angles of obliquity in excess of approximately 40° have been demonstrated in some exploratory tests to not fully engage all layers of the armor panel and deflect off a middle layer into the neck region of the gelatin torso.

For soft armor, NIJ has added a shot located at the top center at the minimum shot-to-edge distances (2 in. or 3 in.) for the respective NIJ HG1 and NIJ HG2 threats at a 45° angle of obliquity between the shot and the armor test item. This added shot applies to all soft armor tested, both planar and nonplanar.

• For planar soft armor, the clay block is rotated a 45° angle of incidence to introduce the obliquity for the shot striking the armor.
• For nonplanar soft armor, the built-up clay of the applique introduces an approximately 15° angle of obliquity by slanting the top of the armor panel back toward the clay block. The clay block is rotated an additional 30° angle of incidence to yield the required 45° obliquity for the shot striking the armor.

This new shot will provide minimum performance for soft armor for handgun projectiles striking that location.

NIJ has also reconfigured P-BFD testing on hard armor plates to include striking the crown on curved plates. The crown is defined as the location of the highest point of the strike face of the plate when the plate is lying horizontally on a flat surface, at the intersection of multiple different curvatures. The placement of a shot on the crown probes the performance of hard armor in a location that may be more vulnerable to penetration due to characteristics of the materials or construction methods used to manufacture plates. This shot location is consistent with testing conducted by the U.S. Army on hard armor to meet its specifications, bringing the NIJ standard into better alignment with U.S. Army testing of hard armor plates.

A previous draft of this standard was published for public comment in the Federal Register.[4]