The level and bulletproof standard of body armor
For the bulletproof level, there are many standards abroad, but the most commonly used is the US NIJ standard du. There are 6 levels in this standard, namely: Class I, Class IIdaoA, Class II, Class IIIA, Class III, Class IV.
The protection capability ranges from low to high. Among them, the ⅢA level requires 9mm pistol bullets capable of preventing micro-impact launch, and the bullet speed is: 420m/s;
All levels below ⅢA are anti-9mm pistols, with a bullet speed: 360m/s or less. Most foreign customers require the protection level of body armor to be ⅢA.
Level Ⅲ protection is to add two 300mm*250mm ceramic composite panels before and after the body armor. The thickness of each panel is 18mm and the weight: 2.6kg. This level requires the protection of NATO M80 bombs (7.62*51 bombs, bomb speed : 800m/s) There are also ordinary ammunition fired by AK-47 and 56 rifles in this level.
Level IV also needs to add ceramic plates, the thickness of the plate: 21mm, weight: 3.3kg, it is required to be able to resist the armor-piercing projectile fired by M1, and the projectile speed: 850m/s.
According to the ballistic performance, this standard divides the ballistic protection capability of body armor into 7 levels. The ballistic threat caused by bullets to the human body is related to the composition, shape, caliber, mass, incident angle and impact velocity of the bullet. Due to the diversity of bullets and the same caliber bullets can have different shells, as well as the existence of hand-loaded ammunition, the body armor that can withstand a certain caliber bullet test in this standard may not be able to withstand the same caliber but different dosing methods. Bullet shooting.
For example, a body armor that can prevent the 40S&W from completely penetrating may not be able to prevent the higher speed 40S&W shooting test. In short, a body armor that can defend against a specific caliber does not necessarily prevent the complete penetration of bullets with different structures or structures under the same caliber.
Bulletproof vests (Bulletproof Vest), also known as bulletproof vests, bulletproof vests, bulletproof vests, bulletproof vests, personal protective equipment, etc., are used to protect the human body from damage caused by bullets or shrapnel. The bulletproof vest is mainly composed of two parts: a jacket and a bulletproof layer. Clothing covers are often made of chemical fiber fabrics. The bulletproof layer is made of metal (special steel, aluminum alloy, titanium alloy), ceramic sheet (corundum, boron carbide, silicon carbide, alumina), glass fiber reinforced plastic, nylon (PA), Kevlar (KEVLAR), ultra-high molecular weight polyethylene Fiber (DOYENTRONTEX Fiber), liquid protective materials and other materials form a single or composite protective structure.
The bulletproof layer can absorb the kinetic energy of the bullet or shrapnel, and has obvious protective effect on the low-speed bullet or shrapnel. It can reduce the damage to the human chest and abdomen under the control of a certain depression. Body armor includes body armor for infantry, flight personnel, and artillery. According to the appearance, it can be divided into bulletproof vests, full-protection bulletproof vests, ladies bulletproof vests and other types.