DuPont’s Spruance facility in Richmond, Virginia recently hosted SSD for an in depth look at Fire Resistance and Ballistic Protection.
Back in the 60s a new class of fabrics was developed, called Aramids with DuPont at the forefront of their creation. Two fabrics in this class have become the cornerstones of modern Soldier Survivability; Kevlar and Nomex. They provide Ballistic and Fire protection respectively. Kevlar was initially developed by DuPont for tire belts but not put to its current use until the early 70s. Nomex on the other hand was quickly integrated into flying and space suits not long after its creation.
The most compelling portion of the visit was the ThermoMan lab. Composed of 122 sensors, ThermoMan was designed with the assistance of NC State. In addition to the mannequin, there is also a skin burn injury model that takes data collected at the sensors and displays how a thermal threat would equate to an injury to the human body. One interesting aspect of the ThermoMan over other testing methods such as the commonly used vertical flame test is that the ThermoMan tests not only the material’s performance but also the garment’s overall design and construction. This is a critical factor in protecting a wearer from thermal threats. If a flame can get inside a garment then the wearer might as well not be wearing FR at all. Interestingly, the pocket configuration of the issue flight suit is designed to provide additional protection for the wearer by doubling the layers of Nomex in certain key areas. Testing has revealed that most injuries actually occur after the flame threat is removed and the wearer is subjected to residual heat retained by the garment.
We witnessed two burns consisting of a 3 second burn delivering 6 calories. It is intended to replicate a JP4 fire. In the first burn, an issue CWU-27/P US issue flight suit manufactured from Nomex III.
As you can see, minimal damage was sustained by the ThermoMan due to the material and design of the flight suit. it is important to note that while the ThermoMan does a great job predicting injuries, actual injuries may vary due to a wearers body and the fit of the garment. Experience has shown that 1% injury equates to 1 day in the hospital. In this case, the ThermoMan indicated 7% injuries.
In the second, a similar looking flight suit manufactured from 65/35 PolyCotton was subjected to the same threat. PolyCotton, a mixture of 65% Polyester and 35% Cotton is commonly found in Chinese made garments. There IS a place for this fabric, but as you will see in the video, it isn’t in a flame threat environment. Rather, PolyCotton is a cool fabric and very good for use in warm climates. The choice of materials goes back to our recent article concerning knowing your equipment, the threat, and environmental conditions and making an informed choice about which equipment to choose. As you can see the PolyCotton not only caught on fire but it continued to burn even after a direct flame was removed. In this case, the ThermoMan sustained 75% injuries.
During our visit to the ballistics lab we witnessed a demonstration of testing of an armor vest and were introduced to the various apparatus used during testing. Additionally, we were given the opportunity to try out first hand correctional armor which is designed to stop stab and puncture threats. We were amazed at how much differently ballistic and correctional armor reacted to the icepick type of shiv commonly found in correctional facilities. The bottom line is that correctional armor works.
We were fortunate enough to be able to discuss a variety of current Soldier Systems issues with the DuPont team but probably the most important message we got was that DuPont is constantly looking at new ways to use their flagship products. Adaptability is the key as they not work to improve the performance of their materials but also as they seek new ways to use their products as well as combine them with other fibers.
While in years past many vendors would have pushed monolithic solutions to threats, it makes more sense now to develop hybrid solutions that combine multiple fibers into a more robust material. This way, the best characteristics of different materials can be combined into a common solution.
Overall, the meeting was excellent and we left with a greater appreciation of the level of commitment DuPont has to protecting our troops and public safety professionals.