What the Controversy Is of Zylon in Body Armor

¶ … controversy is of Zylon® in body armor

The story of the controversy surrounding the use of Zylon® in body armor seems to be a rather predictable tale of the obfuscations of business and government concerning public health and safety, with the expected casualties and penalizing of its whistle-blowers. One of the differences and the many others that have emerged concerning product safety in this post-atomic age is that in this case it has only taken a single death for the biggest name in business to immediately recant and actively pursue some kind of resolution, even if it might not be what its customers would find perfectly ideal.

Zylon® is a fiber filament manufactured by Toyobo, a Japanese firm. It is used in the majority of the most popular bulletproof body armor types, and also in other commercial projects, including flame resistant clothing and equipment. Among the companies using Zylon® is Second Chance, which manufacturers body armor and at least until recently had the lion's share of the market. However, after a police officer on duty suffered a serious gunshot injury while wearing one of Second Chance's Zylon® vests, the company recalled their popular Zylon® lines, citing new research which might show vests were compromised.

Tests performed by Second Chance suggested that Zylon® vests degenerate at an accelerated rate in some cases, and may be no long 100% effective when they reach a slightly more advanced age (over one year). Tests by Toyobo country also show that degeneration does happen, however they claim it is only likely in extreme conditions of heat and humidity, and that body armor companies should be able to design vests so as to escape this flaw. Both Toyobo and other manufacturing companies suggest that their product is not innately flawed, and should be continued in production. So far, Second Chance has been the only company to offer any sort of recall or to discontinue making the vests.

It is difficult to say with certainty what the truth of the matter is regarding the safety of Zylon®. On the one hand, there has only been one failure of a safety vest, and over 2,500 or so instances of vests saving an officers' life. Both Toyobo and the other armor manufacturers seem to have a legitimate set of arguments as to why Zylon® is a dependable ingredient in bulletproof vests. It seems possible that Second Chance is either overreacting to the data they have found regarding Zylon® or that the problem is limited to their methods of using Zylon® and does not lie with the material itself. On the other hand, just one failure does seem to indicate a greater problem, and combining Zylon®'s admitted degeneration issues with the practical evidence Second Chance claims to have gathered does seem to indicate that a serious problem exists. It seems improbable that the leading manufacturer of personal body armor would have the worst and most unsafe design and that its competitors (who do not appear to even be testing their used vests) would not be prone to the same mistakes in construction.

Currently, Second Chance is offering to upgrade all its Zylon® vests for free, or replace them for a sharp discount which varies according to age. (The average life span cited for vests is between five and ten years, so a one-month-old vest is obviously worth more for credit than a five-year-old vest which probably needs to be thrown away anyway) This has not satisfied everyone, and Second chance is currently bound up in a number of lawsuits claiming that they committed fraud by releasing unsafe jackets. On this issue, at least, the reality seems rather cut and dry. Unlike other vest manufacturers, Second Chance is the only one that is admitted there is a problem with their Zylon® vests and offers to replace or repair them. This sort of responsibility is actually uncommon to companies whose products have an occasional failure, and it would be far more typical to deny the accusations and continue selling the vests. The fact that Second Chance has not taken this opportunity to continue releasing killer products is not something they should be punished for, nor does it make sense to penalize them because they were willing to undertake research on product safety and took some time to draw conclusions and present their findings and so forth before withdrawing the vests. Such research is still a step beyond other companies, even if its implications took a month or two to make their way up the chain of command. In short, while it is difficult to say if Second Chance is right that the vests are dangerous, it is easy to say that at the least they should not be penalized for this admission.

Introduction

Body armor has a long history of trial-and-error development, and throughout time designers of armor have struggled to keep up with those who created weapons designed to pierce it. Somewhat amusingly, the first recorded armor was made of light and flexible materials not unlike those used today, if overwhelmingly more low-tech. Body armor and shields were both made from animal skins. However, advanced in technology led to wooden and metal shields and body protection of various sorts. Metal breastplates were common in very early history, and by the Middle Ages full "suits" of armor were created that sheathed every part of the wearer's body in protective metal. While crossbows and longbows that could penetrate armor presented a danger to those wearing full body armor, it was the coming of firearms that finally made metal armor completely outdated. Bullets could easily pierce even strong metal shells. Meanwhile, in Japan soft body armor was being developed that might be considered a direct ancestor of today's bullet proof vests. Using silk, which was significantly stronger than most other natural fibers, medieval Japanese armor makers could create tough garments that would help turn blades.

So when the American military began researching the possibility of creating some sort of body armor that would stop bullets, silk became one of the primary candidates. There was some limited success with this, and silk body armor could stop low-velocity bullets. However, it did nothing against more advanced high-velocity ammunition. Many other forms of body armor were suggested, but none proved to be particularly feasible. The next best thing came about during World War II with the invention of the "flak jacket" which was comprised of a ballistic nylon, and provided some protection against flak and other munitions fragments, though not particular useful against pistols and rifles. Flak jackets certainly saved lives during the war, but they were not a legitimate option for peace time officers.

But in the 1960s, new forms of synthetic fibers made the manufacture of body armor a reality. After extensive research by the National Institute of Justice's Bureau of Standards', it was discovered that the Dupont corporations' material called Kevlar would work remarkably well as ballistic fiber. "Ironically, the fabric was originally intended to replace steel belting in vehicle tires." (NIJ) According to Lester Shubin, how managed the project, "The Army notified me that DuPont had a new fabric to replace steel belting for high-speed tires. When I saw it, I realized it might be a great improvement over nylon for personal armor....and I took a piece of Kevlar to a gun range. The bullets didn't go through." (NIJ)

So Kevlar became the standard for body armor for many years to come. Much of the work on its development was done by government agencies such and the FBI, Secret Service, and the National Bureau of Standards. The government also funded private contractors such as The Aerospace Corporation and MITRE Corporation. Of course the U.S. Army also got involved in research. To some degree this intense study of the nature of Kevlar is different than the work that went into Zylon® as a material, which was primarily explored by independent companies. Kevlar was tested both against a wide range of bullets, and the vest design was finalized. Medical testing oversaw what level of protection was necessary in the regular line of duty, because of concerns about the blunt trauma inflicted by a non-penetrating bullets.

Like Zylon® today, researchers found that Kevlar degraded under less-than ideal circumstances. For example, sunlight, cleaning agents including bleach, repeated washing, and moisture were all listed as potential threats to the integrity of the body armor. One important fact to remember from this era is that this early armor made by the government itself "was designed to ensure a 95% probability of survival after being hit with a.38 caliber bullet at a velocity of 800 ft/s. Furthermore, the probability of requiring surgery if hit by a projectile was to be 10% or less." (NIJ) In short, back in the day when Kevlar was the standard, a 5% fatality rate when wearing the jacket was considered to be acceptable causalities. This is significant to keep in mind when one approaches the story of how a single bulletproof vest failed after almost a thousand from the same company had succeeded (an 0.1% fault rate).

Kevlar gave way to Zylon as the standard because Zylon appeared to be not only much stronger, but also far lighter which made the vests more comfortable to wear. Many officers chose to leave their vests behind when they are on patrol simply because they downplay the risk and because the vests are so uncomfortable. By making the vests lighter and less sticky and better fitted, the number of officer casualties may be reduced.

Understanding how such vests work may also be relevant to understanding the controversy surrounding Zylon®. Bulletproof vests, whether made with Kevlar or Zylon®, are formed with a weave of fibers. When the bullet strikes the vest, those fibers absorb some of the impact and transfer the impetus to nearby fibers so that the energy passes throughout the vest. Each layer of ballistic fabric presents more of a barrier to the bullet and subverts more of its energy. This causes the bullet to become increasingly deformed and slow-moving. By spreading the force of the blow into a larger area, it is possible to dissipate the force necessary to penetrate the body, though severe bruising may occur. Unfortunately, without having an unreasonable number of layers (which would make the vests rigid and difficult to wear on a regular basis), it is only possible to protect against low and medium energy handgun fire. Rifle fire, teflon coated bullets, and other such extreme variables may make it possible to pierce through even the best and most cutting edge body army. This is also important to keep in mind when considering the claims that a vest has "failed" -- there is always a chance that the threat against which it was guarding was too difficult for the vest even at its prime. For example, the officer who was injured in the recent vest failure still has the bullet lodged inside his body, so it is impossible to tell at this juncture whether the bullet might have had some kind of special external coating or have been specifically modified to defeat body armor.

The types of fiber currently used in creating body armor are: Kevlar, a manmade organic fiber, of which there are a number of varieties; Spectra fiber, which is a polyethylene fiber that has a vaguely gel-like appearance; TWARON, which has a patented Microfilament technology and is exceptionally light; and Dyneema, which is also remarkable light with high energy absorption. Zylon®, however, which is considered the strongest fiber known to man, until recently remained a favorite for personal body armor.

The change was really precipitated with a single failure that led to the unveiling of a growing body of research regarding the Zylon® fibers potential failures. As the National Border Patrol Council reported the story, "It began with a single gunshot. Last summer, an undercover police officer stepped out of a van in Pennsylvania to make a drug bust and was shot in the abdomen. The bullet penetrated the front panel of his body armor. The officer survived, but the damage - to him and to an industry that exists specifically to protect law enforcement - was done." Almost immediately, a great out roar began among those who had purchased the same sort of vest that this officer, Limbacher, was wearing at the time of the shooting. It has been estimated that approximately 200,000 police officers have and wear Second Chance Zylon® vests of the same sort. The outrage over one near-fatal shooting persists despite the fact that Second Chance vests have "recorded more than 900 'saves' - instances when medical personnel have confirmed that its vests protected an officer from serious injury or death [and] The Ultima and Ultimax vests [in question] account for 37 of those saves." (National Border Patrol Council)

Today the controversy is as to whether or not Zylon® should continue to be used in bulletproof vests, and also whether or not Second Chance industries should be held responsible for the entire financial costs of replacing the 200,000 plus vests in use today (at a cost of between $500 and $1,000 a piece, which would certainly bankrupt the company). It is to the point of answering this controversy, or at least understanding it, that this paper is focused.

Literature Review

The literature review would begin best with the report from the Pittsburgh Post-Gazette that broke the story, "Bullet Pierces Officer's Vest During Drug Bust." The story it tells is a little more complicated than that explained by the National Border Patrol Council. Around Forest Hills Plaza in Pennsylvania, there was a large drug bust involving 14 officers, of which 9 were undercover. Police Officer Limbacher was not undercover. He wore a bulletproof vest under a task force jacket. When the other officers were rounding up suspects, Limbacher identified himself as a police officer and confronted one suspect, who opened fire on him. A bullet pierced his arm (which was not covered) and also hit him in abdomen. This was when his vest failed. ." "..'[The bullet] passed through the vest,' Forest Hills Police Chief William Fabrizi said yesterday, reflecting on what he said was the first shooting of an officer in his department's history. 'They were just issued, and they're not more than five months old.'" (Pittsburgh Post-Gazette Staff Writer)

Doctors decided not to remove the bullet because to do so would endanger the officers life. Investigators believe it was fired from a."40-caliber semiautomatic handgun that was later recovered from a pizzeria parking lot where it had been discarded," (Pittsburgh Post-Gazette) though the exact sort of bullet could be questioned. According to spokesman from Second Chance, the vest should have been able to stop a bullet from such a gun at pointblank range. However, they also point out that an altered bullet, "coated with Teflon, for instance, or made with a steel core" (Pittsburgh Post-Gazette) would have been able to pierce a vest even in perfect condition. A bullet that had been doctored might explain the failing of the jacket.

Another view of the problem, "Faulty Body Armor Coming Under Increasing Fire," discusses the aftermath of this shooting. Four states, at last count, have started investigations into the matter, suggesting that Second Chance intentionally sold vests it know to be defective. U.S. Attorney General John Ashcroft meanwhile has initiated a wider investigation into Zylon® itself. "That inquiry underscores growing concern within law enforcement that the problem rests not with Second Chance's manufacturing but with the durability of the fiber the vests are built on." (National Border Patrol Council)

This is a serious concern, the article explains, because both Second Chance and Toyobo (who manufactures Zylon®, it will be recalled) claim that the flaw is not their fault. Both claim that the engineering flaw belonged to the other company. In the spring, Limbacher was shot. By fall, Second Chance had released its own private studies saying that Zylon® deteriorated much faster than should have been expected. They were met with surprising outrage from consumers: "[they] tried to blow the whistle on Zylon®, only to be flooded by allegations of fraud and deception." (National Border Patrol Council) Shortly thereafter, Second Chance handed over many of its internal documents to consumer groups and to the government. These document showed that the body armor weakens over time, and even under ideal circumstances is considerably less powerful after a few years. One document by Toyobo suggest that Zylon® can lose up to 30% of its strength.

As may be apparent from the sources of these quotes, Toyobo's own research might indicate that Zylon® has some failings. So it would not be fair to blame Second Chance exclusively if the problem lies with Zylon® itself. This is certainly the position of Second Chance, which claims that the "company was being demonized simply because it was the first to raise a red flag... We blew the whistle... So we pay the price." (National Patrol Council) The Fraternal Order of Police agrees to some extent, suggests that this is valid. He says it would be hasty to condemn Second Chance when other manufacturers are not yet even admitting that it is a problem, Why, they ask, haven't other companies come forward with plans to replace Zylon® The answer, of course, is that most other companies still support Zylon® and use it in most of their lightweight designs.

Second Chance continues to claim that it did not knowingly sell defective vests, but rather than all items were sold at a time when they were believed to be up to code and safe. Offering a steep refund is an important part of proving that sincerity, as is the practice of offering free "patches" (ceramic plates designed to go in lining of the vests) that will ascertain their ability to withstand bullets. However, a number of lawsuits both at the state level and class-level ensued accusing the company of both fraud and negligence, and demanding that rather than offer a replacement plan based on the number of years or months which the vests had been owned (e.g., based on their depreciating value) but on the original purchase price or the current replacement price.

A third article, "NH Cops Told Vests Not Bulletproof," further describes the reaction of police officers and the proposed exchange. "We are trying to be tactful, but people are very agitated. This was a company we trusted our lives to for many years." (Exeter Newsletter) This article discusses the idea of a patch kit, and the rage with which it is being greeted by police officers who want their vests replaced free of charge. However, it also admits that Second Chance is doing a better job than the other armor companies of admitting the flaws with Zylon®. In 2001 Toyobo published data:

On how heat, humidity and light caused severe degradation of the so-called indestructible material over time. Since then, the research has been updated and provided to all of Toyobo's customers. Until last month, police had not been notified.... Zylon® retains 35% of its original strength when exposed to six months of normal light... 'any visible light,'...[and] significant degradation because of exposure to any form of humidity. This includes the humidity that occurs between the officer's perspiring body and the vest he is wearing, which according to tests, can reach 100% humidity. The degradation increases when the vest is exposed to heat above normal room temperature... Essentially, a vest that is six months old may have lost a significant amount of its protective strength during normal everyday use." (Exeter Newsletter)

Some armor companies, including German BSST, have recalled all Zylon® vests. However, American companies including Second Chance relied on their own National Institute of Justice tests, which do not test for degradation. Though Second Chance did start testing used vests at that point, it is interesting to note that they might have acted first on the warnings of Zylon®. Of course, Toyobo insists that these findings do not keep the material from being suitable for use. "We felt that Toyobo's results were based on laboratory tests that were not realistic to conditions the vest would really encounter," (Exeter Newsletter) Second Chance originally said, which is precisely what other American companies continue to say.

It is believed by many who are suing the company that this evidence that the vests were defective ahead of time means that they should be liable to replace all vests purchased since then. If they had not known, maybe it would be acceptable to just patch the vests or give a discount, but as it is this is being taken as a matter of fraud. Still, the main issue to be resolved continues to be whether or not Second Chance will replace the vests free of charge.

To analyze whether Second Chance is being fair with its "patch upgrade" one might wish to turn to a report on the subject by the National Institute of Justice. The NIJ says that they cannot judge the upgrade offer for Zylon®. Models are compliant, they explain, only if they are identical to the version which was tested. NIJ does not test used armor or modified armor, and cannot comment on the patches. They do stand by their original testing of the Second Chance vests, and proceed to advise against improper care and storage of vests, promote quality cleaning of armor, and the avoidance of extreme conditions such as automobile trunks and non-climate-controlled storage areas. It seems almost as if the NIJ is passing on blame for the failing of the vests to the officers who have owned them, which may or may not be a valid point.

With the support of NIJ, other American companies do continue to produce Zylon® products. To demonstrate the sort of logic that continues the use of Zylon®, one can look at the FAQ release from Armor Holding Products Division, one of the major remaining manufacturers of Zylon® body armor. They begin by explaining how wonderful Zylon® is, with its "high tensile strength and thermal stability and flame resistance when compared to organic fibers." (Armor Holding Products, 1) They explain how Toyobo sells Zylon® in spools of filament yarn, and it is only this raw yarn which is tested by Toyobo for flaws. They further claim that once the yarn has gone through their patented processes to be made into a vest, it is protected from degradation to a large degree. They explain that ballistic materials can always degrade, "It is an industry recognized fact that the various mechanical properties in ballistic materials can, over time, degenerate...[but] We anticipate this...and provide clear care and use guideline." (Armor Holding Products, 1) These guidelines, if followed, will supposedly protect the vest from degeneration.

Armor dismisses the tests performed by Second Chance as being "vague" and likewise explains away the Toyobo results. They admit that high heat and humidity can effect their product, but claim that the Toyobo tests with high heat and humidity are generated artificially and do not resemble actual working conditions, and that furthermore any important degradation occurs in the first few months while still in storage and is thus unrelated to the success of the vests. "Toyobo has placed as-produced Zylon® fiber in a chamber that is set to 104*F and 80% relative humidity, 24/7, 365 days of the year... intentionally stressing the raw yarn." (Armor Holding Products, 3) This is different from real aging, they say, just like ironing clothes at too-high of a heat setting is different from the process of normal aging for properly cared for clothing. "No test [is] universally agreed upon that can simulate 10 years of aging" (Armor Holding Products, 4)

Their letter to customers reads: "while we applaud their prompt action to correct performance deficiencies discovered in some Second Chance vests, it is unclear exactly what 'wearing out faster' means, or the basis on which they make that statement of conclusion. This ambiguity is causing concern and confusion..."

In short, Armor says today exactly what Second Chance was saying for the last two years before an officer died. Honeywell Spectra, another maker of bulletproof vests, likewise denies the validity of the tests performed by Second Chance (whose design, they suggest, is just flawed) and Toyobo (whose data is irrelevant). Honeywell focuses on Toyobo's tests as being irrelevant. "ambient age samples usually do not exist" (Honeywell) so Toyobo must use accelerated aging to get the products to market sooner, but it has failures. Putting more severe stress (such as higher temperature or humidity) than would otherwise exist might be an unfair way of testing because "Although accelerated aging techniques are well documented in some circle, information on the use of these techniques is limited in the ballistic protection field...data [is] almost nonexistent... results from accelerated aging work will generally be conservative." (Honeywell) They call the results Toyobo has found to be unrealistic negative data, and claim -- as the company would wish -- that it is perfectly all right to go ahead with making Zylon® jackets until field test show otherwise. Of course, neither Honeywell nor Armor appears to be aggressively researching used product.

To balance out these views, one should return to Second Chance, who did actually do extensive testing of used vests. They respond to questions regarding the way in which their competitors continue to use Zylon® by responding: "As we've said before, we cannot speak for our competitors. We can only tell you what we are doing and why. However, we can tell you that we believe the problem is inherent in the fiber. We would hope that any manufacturer would test a large number of in-use vests, of varying age, and from agencies across the country before making any statements." (Second Chance)

They go on to explain why, like their competitors, they spent so long in denial about Zylon® and the dangers it posed. They agree that Toyobo's original data was based on only a few months of unrealistic conditions, and that it might not be relevant to processed Zylon® within the vest. They preferred to protect their investment and share of the market by first testing the used vests themselves before starting a nationwide recall and panic regarding the safety of the vests. A letter from the president of Second Chance further explains that not all vests are actually negatively effected, which slowed down testing. "there is no one set of circumstances that can be a leading indicator of performance. Age, exposure to heat, humidity, sunlight, wear, care, in service life, flex fatigue and other factors all can have an impact on the performance of any used armor. You just can't tell without ballistic tests that destroy the armor." (Second Chance)

Second Chance seems genuinely to care about the effects of Zylon® armor on the police force, for they openly discuss its early degradation rather than claim that Limbacher's case was a freak accident in keeping with the small failure percentage rate prescribed by the NIJ. "the early degradation of this miracle fiber (Zylon®) was not predicted by anyone in our industry... Little did we know where this new fiber would lead us." (Second Chance) As mentioned repeatedly, it is for this reason that they propose patching existing jackets or replacing them on a sliding scale.