Stab vest

A stab vest, or stab proof vest is a reinforced piece of body armor, worn under or over other items of clothing, which is designed to resist knife attacks to the chest, back and sides. Stab vests are different from bulletproof vests, most of which offer protection against firearms but afford little against stabbing with sharp-tipped objects such as knives; most stab vests afford less protection against bullets, particularly those of high caliber, but are designed to prevent serious injury by prohibiting knife penetration beyond a few millimeters. Stab vests are also needle and slash proof.

In the mid-1980s the state of California Department of Corrections issued a requirement for a body armor using a commercial ice pick as the test penetrator. The test method attempted to simulate the capacity of a human attacker to deliver impact energy with their upper body. As was later shown this test over stated the capacity of human attackers. The test used a drop mass or sabot that carried the ice pick. Using gravitational force, the height of the drop mass above the vest was proportional to the impact energy. This test specified 109 joules (81 ft·lbf) of energy and a 7.3 kg (16 lb) drop mass with a drop height of 153 cm (60 in) and an ice pick with a 4 mm (0.16 in) diameter with a sharp tip with a 5.4 m/s (17 ft/s) terminal velocity in the test. The California standard did not include knife or cutting edge weapons in the test protocol. In this early phase only titanium and steel plate offerings were successful in addressing this requirement.

It should be noted that these textile materials do not have equal performance with cutting-edge threats and these certifications were only with ice picks and were not tested with knives.

The PSDB work studied what kind of weapons are commonly used in stabbing attacks and what levels of impact energy fit young men are capable of generating during an attack. The study resulted in minimum performance ratings for armor used in the UK, as defined under PSDB publication 6/99. The PSDB standard was replaced in 2007 with the current Home Office Scientific Development Branch (HOSDB) publication No. 39/07/C which governs stab resistant body armor performance in the UK. This updated standard introduced a more stringent testing procedure with more drops than the previous standard plus the introduction of the P1/B Blade which is found to be more aggressive that the older P1/A Blade.

...
Wikipedia