The NIJ standard specifies that “Four complete armors, selected at random and sized to fit a 117 cm (46 in) to 122 cm (48 in) chest circumference, shall constitute a test sample. (Note: The larger the size, the more likelihood that all ballistic testing will fit on just two complete armors.)’ In quality assurance,

Table l—Types of Ballistic Resistance Defined by NIJ

Standard 0101.04 / 0101.05 / 0101.06 in Terms of Bullets and Velocities

Specified for Testing

    Bullet Mass Finumum Velocity
Type / Level Bullet caliber and type (Grains) Ft./sec.
 I 22 long rifle high-velocity / .38 round-nose lead   40 / 158 1050 / 850
 IIA

.357 jacketed soft-point / 9-mm full metal jacket

158 / 158 1250 / 1090
 II

.357 jacketed soft-point / 9-mm full metal jacket

158 / 124 1395 / 1175
IIIA

.44 magnum lead semi-wad-cutter gas-checked / 9-mm full metal jacket

240 / 124 1350 / 1450
III  7.62 mm full metal jacket 150 2750
IV .30-06 armor-piercing 166 2850
Special custom   Custom custom

% finumum velocity; the maximum velocity for a fair hit is 50 ftls greater.