Beyond the flak jacket

With today’s high-performance fiber technology, soft body armor offers improved ballistic protection.

The technical textiles industry that focuses on ballistic protection has made impressive technological advancements, but as much as the label “bulletproof” is in common use, when used with textiles, it’s simply not accurate. There are no bulletproof fabrics. A better phrase is “soft body armor” (SBA).

While many may be strong fabrics and combinations that offer a great deal of protection from bullets or shrapnel, chances are there is a bullet with a hardened projectile or a powerful enough charge that it will penetrate and cause death or serious injury. The goal is to provide as much protection as possible and the least damage consistent with the hazard.

There are two primary markets: military and law enforcement personnel protection. Within each sector are many variables, calling for special add-ons or other modifications. This article will focus primarily on products for law enforcement.

Ballistic protection, traditionally

While bullet-resistant applications inevitably have some bulk, vests (the most widely used kind of protection) must be as lightweight and comfortable as possible for someone who needs it to actually wear it. Various levels of protection and vest construction have been available. Like all protective clothing, compromise is the key word. The greater the protection, the heavier and bulkier the garment was likely to be. It can be reduced to need, the hazard and risk, comfort and cost.

Textiles in some form have been used for centuries for protection from arrows, swords, knives and even bullets. Even layers of cotton or nylon yarns, sometimes combined with metal plates, have been used. The “flak jackets” of World War II were designed to protect soldiers from the shrapnel that flew about as a result of a hit to their aircraft. These vests were never considered bulletproof. With the advent of high-performance fibers, today’s protection is truly new.

Specific-use construction

Ballistic vests supplied for law enforcement are primarily for handgun protection. Rifle-resistant materials, such as those for the military and high hazard officers, need higher levels, often incorporating a high-strength plate used with the vests. Police wear the vest representing the types of weapons likely to be encountered, most using a vest that at least provides a level of protection equal to the guns they and their colleagues carry.

The mechanism of SBA involves catching and deforming the bullet, absorbing the kinetic energy and dispersing the impact throughout the other yarns or inserts in the vest. Secondly, the impact and the process of stopping the bullet will cause a back force—a cone or impression behind the vest next to the body—as the bullet tries to push through but is stopped, impacting the wearer’s body to a certain depth. Vests are designed and rated to stop specific bullets resulting in a backforce impact within a non-lethal depth, from 23-44mm. Though serious injury could occur, the chance of  survival is much better.

Testing and standards

Standards and testing are especially critical in this market. The National Institute of Justice (NIJ) is the U.S. government agency for setting standards for ballistic protection. The NIJ defines five main levels of protective SBA (I, II, III, IIIA, IV and V) with each level giving protection from more powerful projectiles. “Ballistic Resistance of Body Armor NIJ Standard-0101.06” (NIJ 06) establishes minimum performance requirements and test methods for the ballistic resistance of personal body armor designed to protect the torso against gunfire. As a minimum, police officers are recommended to use level II, though others feel level IIIA should be selected. It seems reasonable to suggest that the level of protection should at least be suitable protection from impact by the officer’s own weapon. (Ten percent of police bullet injuries are from their own weapons.)

While the NIJ is the U.S. standard, other countries and NATO have others, and still more are being developed. Unfortunately, the array of standards is not exactly comparable. Those who supply materials or products that require certification should be clear on which standard is being applied, and then test accordingly.

Materials used

The most widely known fibers used for SBA are Kevlar™ paraaramid from DuPont and Twaron™ from Teijin Spectra™. Honeywell’s Ultra High Molecular Weight Polyethylene, UHMWPE, an extremely high-strength olefin fiber that is said to be 15 times that of steel (mostly due to its low specific gravity) ) is also used extensively in SBA. Dyneema™, by a company of the same name, is another UHMWPE used.

DuPont’s Kevlar defined the modern vest about 40 years ago with its use of the high-strength fibers in SBA. Even today, many refer to them as “Kevlar,” even if it is made of another material. Though initially of high-denier fibers, mimicking the so-called “ballistic nylon,” a trend has been to use tight weaves in lower deniers (200-400) to keep the weight of the vest down.

Many vests are made of all woven fabric from a number of suppliers. Honeywell developed a special method of putting together a sheet of resin-impregnated parallel yarns—not interlaced by weaving and with no crimp—by cross-laying multiple layers over each other at 90-degree angles, either of all Spectra (SpectraShield™) or in combination with para-aramids and films (Gold Shield). The theory behind SpectraShield is that a projectile (bullet) may strike at an interlace point of a woven fabric, reducing its effectiveness, but by using all parallel yarns, close together, this reduces the potential for the projectile to slide between fibers.

The trend has been to provide hybrids for increased protection, fabric combined with panels of Shield products, all UHMWPE or combined with para aramids.

Level IIIA is the standard most police specify. Combat soldiers, however, must utilize inserts and slightly different carrier designs as they are more likely to be impacted by higher-caliber rifle bullets.

There are many other fibers available for use in SBA. All the fibers used in SBA have high strength and some elasticity, making them suitable to absorb and dissipate the shock of being hit with a projectile. Each has its own concerns: longevity, wear and tear, and launderability. One famous situation involved PBO, polybenzoxazole, (Zylon™ from Toyobo), a fiber about 1.6 times stronger than Kevlar. Quickly adopted as a premium product (highly effective but lower in weight) the product was withdrawn when several failures resulted, one which resulted in death. It was found that it degraded under UV light.  The NIJ has decertified all vests with PBO so their use has essentially been discontinued.

When an all-woven fabric is used in vest construction, up to 22 layers may be used. In the Shield products, there are far fewer layers, reducing the weight, while providing high levels of performance.

In addition to the actual vest fabric that provides protection, there are various plates that can be inserted within several pouches in the vest carrier. These may be rigid metal, such as titanium; flexible metal variations, or ceramics; or ultra-tight para-aramids to offer greater cut, slash or puncture resistance. Each manufacturer claims features such as more comfort, flexibility, protection against stabs, cutting and slash hazards.

Finally, the carrier, an important part of the ensemble, provides the covering for the ballistic panels and pockets for metal or other inserts for protection at a higher level. They are most often of fairly mundane fabrics like polyester/cotton or 100 percent cotton, and sometimes treated with antimicrobials. The carrier allows breathability and greater comfort. Urethane shoulder coated straps or some other system is included to reduce the strain on the wearer and allow for tightening – a non-advanced textile opportunity for an advanced textile application.

Cut and slash resistance

Not all soft body armor is for projectiles. Some products protect from cut and slash, stabs and knife threats. More corrections officers are injured or killed with homemade shanks, ice picks and knives than are shot. Warwick Mills, Ipswich, N.H., produces fabrics, components, and garments for such cut/slash/stab-resistant material.

Turtleskin™, a tightly woven fabric of high-strength paraaramid, often with a coating on one side and a conventional aramid fabric on the other, offers good stab and cut/slash protection when properly utilized. Though not designed for ballistic protection, the material is often incorporated as an insert in ballistic vests for added cut/slash/stab protection. Turtleskin is not offered alone for ballistics, but engineered to reduce non-penetrating injuries associated with blunt trauma to the chest and torso.

Charles Howland, Warwick’s president, says, “We focus on multi-threat armor: knife spike, pistol and fragments. This approach gives the user comprehensive protection. The multithreat offering has been popular in Europe for years; it is now being adopted in the U.S. We are now supplying the U.S. Army with multithreat for MPs.”

It is a “mosaic” approach, he says, using a variety of materials, including the tightly woven paraaramid, as well as special flexible metal inserts. Holland points out that their largest customer is Howland’s police force where the product is used extensively. Other customers use the material for gloves, for example.

(NIJ 06 applies only to ballistic protection and does not cover cut/slash/stab requirements. For that, see “NIJ Standard-0115.00, Stab Resistance of Personal Body Armor.”)

Blast protection

De-mining or bomb blast protection apparel is a specialty field utilizing many of the principles of ballistic protection. They are heavy, cumbersome suits designed to withstand and disperse the pressure of a bomb blast. Usually made of thick Kevlar fabrics over low density foam or plastics, they are designed to stop or decrease the blast wave pressure being transferred to the wearer. Since dexterity is essential in defusing a mine or bomb, there are usually no gloves worn, leaving the wearer dangerously exposed.

The design of the bomb suit is undergoing continuous refinement and testing to make it more effective, with reduced weight, and providing improved dexterity and agility. The NIJ is working on standards, so there is opportunity for discussions.

Blastproof curtains for storefronts and other public places are used in many parts of Europe and being studied for use in the U.S.

Protection of the head against ballistics is a concern. Helmets of reinforced materials, often Kevlar, provide protection against bullets or shrapnel. Liners of Kevlar-reinforced materials are now standard, but better effectiveness and lower weight are goals. A new helmet, developed by the military, is 16 percent lighter and will stop a 9mm bullet, and will likely to be adopted for tactical units.

The larger market

Accurately determining the size of a market is difficult, because how things are counted or included may vary. One estimate (2011 BCC Research, a market research service) indicates a market of “advanced protective gear and armor” was worth about $4 billion in 2010 with a compound annual growth rate (CAGR) of 6.1 percent between 2010 and 2015. Of that amount, though, ancillary products (gloves, head and eye protection, respirators) accounted for almost 60 percent of the total, while thermal (fire service and related items) was the second largest at about 14 percent, or $566 million. Body armor followed at about $500 million in 2010.

Other studies offer varying figures, but they seem to agree on a 5-6 percent CAGR. Europe and the U.S. account for the major share, although Southeast Asia and the Pacific are seen as major growth areas. India, for example, is becoming a major exporters to other countries.

The BCC study reveals the disparity in numbers for advanced textiles at times, as it breaks the overall total down to include the aforementioned ancillary products (some include them as well as similar products elsewhere), chemical/biological/nuclear markets, as well as thermal and armor.

A recent report available on Reportlinker.com indicates a global market of $1.5 billion for 2012 for body armor and personal protection with a CAGR of 4.89 percent going to $2.4 billion by 2022. As you can see, there are discrepancies, most likely on what is counted. Taking numbers at face value without sorting them out for a particular market segment can lead to inaccurate assumptions. This market is specialized and complicated, but it is also substantial. Careful study is advised for those interested in participating.

Imports

SBA, as with many technical textiles, is subject to competition from imports. India, for instance, has a hearty industry supplying SBA to its own military and to countries outside India. MKU is India’s leading producer of SBA, modifiying its offerings to meet the needs and standards of the countries where purchased. They are fully certified for NIJ 06. MKU’s paraaramid fabric is woven in India by Kusumgar Corporates, likely India’s only weaver of ballistic fabric. They also use olefin materials from Dyneema and Honeywell.

Neeraj Gupta, president of MKU, says that he personally does not see a major opportunity for MKU in the U.S. It is his opinion that the U.S. market is over-supplied and has many small players. And overall, the market is declining, he believes. Lack of experience in the U.S. market, the local need for service, and other issues are barriers, as well. Nonetheless, he participates in a number of U.S. trade shows.

China is somewhat of a threat, Gupta says, but mostly for those “who are not so cautious about quality.” How much of China production gets into the U.S. is uncertain.

Most of the production used in the U.S.—and virtually all of the military versions—are produced in the U.S. But there are some imports, especially among smaller companies eager to get in this industry. As a life-saving issue, it is essential the standards and testing are adhered to, preferably with third-party certification.

Legal issues

It is not illegal for civilians to own ballistic vests, and, in fact, many do. Convicted felons, however, are not permitted to own or possess such a vest in most states. Many countries also have their own standards as to who can own such equipment.

As for liability in the event someone gets killed wearing gear made with your material, regular liability insurance is mandatory. You may likely be covered already under your current policy. Again, make sure your material meets the standards in every respect.

Opportunities

Weavers used to weaving heavy, beat-up (tight) fabrics of certain weights, and who are competent in testing and quality, might be able to switch over to weaving SBA constructions. There are a number of large companies, such as Armor Holding’s Safariland, US Armor, PACA Body Armor, TurtleSkin Body Armor, Point Blank Body Armor, KDH Defense, and a large number of smaller companies that are in some form of SBA production and distribution. The Internet is full of information about this industry; it is recommended one be thoroughly grounded in what is needed.

Where to now

Current efforts seem to focus on new materials. Several new fibers have been developed, mostly abandoned for one reason or another. Aasron Tomich, program manager for TEAM, a company doing extensive research on hard armor, says TEAM is looking more to S2 fiberglass composites, and carbon is expected to play a part. While Tomich’s work is not directed to soft body armor, technology has a way of migrating from one to another.

Spider silk, for example, is one fiber that continues to be reviewed, as it is an extremely strong material that would no doubt result in lighter weight materials. But how to extract the protein I spider silk in a commercial and cost-effective process has been difficult. (For new information on this technology, see “New ‘Big Red’ spider silks offer superior strength” on this site.) Carbon nanotubes may emerge as a major force but the same difficulty as that of spider silk keeps it in the lab for now.

Riot gear has a different requirement. Blunt force trauma to the body is common; cut slash and stabbing protection is also needed. Most gear is made of fabric-covered foam. Auxetic materials may have good potential in riot gear. Simply stated, auxetic materials have a tendency to get larger as they are stretched, unlike a rubber band that gets thinner. That property provides greater coverage for the blunt force encountered in riots. Dow Corning has a similar material on the market, used in a coating, for motorcycle rider fall protection. (See “Auxetic advances” on this site.)

The risk factors are great—for the user as well as the supplier. Modern fibers, construction techniques, standards and required testing have made for vast improvements in the use of ballistic materials; yet, there have been materials that were found to have flaws.

Improvements are constantly being researched and tested. And while the focus may be on the fibers and components in hybrid products, mainstream companies that do cut-and-sew work have a good opportunity to participate by developing more effective carriers, straps, and storage units for these highly specialized applications.

Could this market offer opportunities for your company? It’s a challenging environment, but time spent in researching and studying it could be worth your while.

William C. Smith is a technical textile consultant. He can be reached at billsmith@intexa.com (www.intexa.com).