Whether you are interested in it as a security measure in an environment where guns are used, or as a protective precaution in a time where gun violence is common, you will want the best quality body armor for the job. In addition, though, when choosing body armor, you get to choose the
level of protection it offers, each level offering its own advantages and disadvantages.
A good starting point is to remember that although they can be combined, bulletproof vests are not inherently stab-proof. The materials are made in different ways to stop different types of attack and are not capable of more than they promise. A stabbing attack has significantly different requirements to a gunshot.
Now, bulletproof vests come in two different general levels - soft armor and hard armor. Soft armor resists a lower level of attack than the hard plates used in hard armor, but is generally more wearable day to day and convenient. If you only realistically need protection lower than level 3, soft armor is the way to go. This includes some body armor of level 3a, and level 2 body armor. The
NIJ (National Institute of Judgement) has set standards defining several different threat levels, between 2 and 4. Soft armor is made out of woven or fibrous materials that resist certain types of ballistic attack (gun shot). These can include Kevlar, Twaron, Dyneema, or others, all designed specifically in a way that stops the bullet from puncturing the skin. Body armor of any level promises only to resist the bullet piercing the skin. The energy the bullet carries with it will still hit with the same impact force, and you have to be ready for that. It is recommended that wearers of hard armor wear a layer of soft armor underneath, to further minimize the risk of blunt force injury.
Within the category of hard armor, there are two main types of plate used: Ceramic plates, and Polyethylene plates. Both have pros and cons. Ceramic plates are available at higher levels of NIJ certified ballistic protection, however, they are designed to break upon impact, thus scattering the force of the bullet, which means that they are far less effective with any consecutive shots, and can protect against fewer bullets. Polyethylene plates can handle more rounds of bullets, as they use the spin of the bullet to slow it down. They can withstand more attacks without significant loss of effectiveness, but they are not certified up to level 4 of ballistic protection.
Two common abbreviations used when talking about body armor are ICW and STA. These refer to the plates' ability to stand alone (STA) and don't need any other bulletproof protection other
than what they themselves provide, or their designation as meant to be worn with other bulletproof protection underneath, such as soft armor, which is called ICW, and stands for 'in conjunction with.' Many ballistic vests are designed with a pocket meant to carry ICW plates, so that extra protection can be added if desired. STA plates are thicker and bulkier but offer the protection alone.
Other protection protocols that have been established outside of the NIJ are SAPI (Small Arms Protective Insert), which is designed
with military specs in mind (followed by the more recent ESAPI, which stands for Enhanced SAPI), the IOTV (Improved Outer Tactical Vest), and the MTV (Modular Tactical Vest). Additionally, the DEA and the FBI have their own protocols, and there exist "Special threat" plates that are made for specific scenarios outside of the typical protocols. An example of these are the Venture FM-STX, designed to be thin but protect against most common threats. But they are not yet NIJ certified due to insufficient testing.
Level 3 body armor (available in ceramic and polyethylene) are rifle plates, also known as hard inserts. They offer protection against six spaced hits of 7.62X51MM NATO (Full Metal Jacket) travelling at 2,750 feet per second, or a .308 Winchester hunting round. It's important to remember that a plate rated by the NIJ to stop a particular threat isn't designed for things outside of what it offers, even if it is a smaller calliber or slower shot. This is why it is important to understand the capabilities of the armor you are looking at and choose based on your realistic expectation of what you need it to protect against. Higher level armor can sometimes not protect against lower level threats. Level 3 or 3+ are generally thought to cover most commonly needed scenarios and so is the most common body armor to purchase, but you should always verify that it has the specs for exactly what you need.
