Image credit: REUTERS/Hamad I Mohammed
E&T spoke to the designers of the material used to develop the suits and apparel for racing drivers – an innovation that provides the valuable seconds racing professionals need to escape fires that result from both on-track collisions and pit accidents.
If the Bahrain Grand Prix on 29 November reminded us of anything, it would be that motor racing is a very dangerous sport. As you may have seen on the TV during the race, or later in the news, Formula One (F1) Haas driver Romain Grosjean’s car became engulfed in flames when he veered off the track three corners into the first lap, tearing the Haas VF-20 car in two. Medics helped him escape the frightening incident, fortunately, without any serious injuries: Grosjean sustained only minor burns on his hands and feet before being rushed to the hospital.
While Grosjean credited the ‘halo’ device – a ring of titanium that sits above the car’s cockpit to protect the driver’s head from flying debris – with saving his life, his suit helped protect him from further devastating burns caused by the fire. How does this technology provide long-lasting protection for these passionate speedsters?
When drivers are tearing around a track at 200mph, the last thing they want to think about is the effectiveness of their flame-resistant protection – they just want to know that it will keep them safe from harm if an accident like Grosjean’s does happen. If it does, and their overalls catch fire, an inner body-suit called ‘Nomex’ - a fire-resistant, meta-aramid and lightweight fibre developed by chemicals company DuPont - can help prevent burns and extinguish the fire.
“While graphic, the [Grosjean] crash has illustrated to many the incredible developments in safety-specific material science, technology and engineering advancements,” says Amr Moniem, the global market leader for DuPont Personal Protection. “Over the last 20 years, supported by tighter FIA (Fédération Internationale de l’Automobile) regulation on safety procedures and personal protection equipment (PPE) performance standards, companies like DuPont have been working to develop the most protective materials possible for high-risk environments like F1.”
The material was first discovered by DuPont scientist Dr Wilfred Sweeny in the late 1950s, Moniem told E&T. “The development of Nomex was actually stimulated in reaction to the death of race car drivers in fiery crashes; it went into full commercial production in the late 60s and thus started its journey into PPE.”
Its first generation was short-staple (relatively short fibres), progressing into a shiny filament. A key element for the application of Nomex in racing suits, Moniem highlights, other than its protective properties, was the look and feel. “Much research and testing continue today to make Nomex garments that are even more comfortable, lighter as well as safer.”
The first use case for safety within F1 was seen in 1969, when Italian-born US former racing driver Mario Andretti survived an Indy 500 practice day crash and fire while wearing a racing suit made with Nomex. Today, around 95 per cent of racers around the world wear suits and apparel made of Nomex. Moniem says the material has “revolutionised PPE and safety standards”, with the material also found in garments and apparel for firefighters, the military, law enforcement and industrial workers, as well as racing professionals, to protect them from heat and flame hazards on the job.
Moniem adds that the protective apparel such as racing or fire suits, gloves, underwear and balaclavas (the head covering under the helmet) worn by racing drivers and their team members are manufactured by several specialist global companies to meet specific safety standards defined for each use case by the FIA.
“In the case of the fire suit for racing", Moniem explains, "the suits are a multi-layer (usually two or three) approach with an outer shell for durability and toughness with breathable inner layers designed to provide additional insulation from heat while wicking away moisture. Nomex fabrics woven in different configurations can be used for each layer.”
Although the DuPont team has been fortunate enough not to witness many fatal incidents, especially since safety has improved over the last 20 years, Grosjean’s crash has highlighted that these events are unpredictable. This means that all PPE should be optimised for any scenario, Moniem tells E&T. “Although the specific details of this particular incident are still being fully investigated, it was reported that the driver made impact with the barrier at 137mph, sustaining an impact of 53G, and was exposed to flames for approximately 28 seconds before walking out of the fire.”
To ensure that Nomex is ready for the threats that racing drivers, firefighters, military and other personnel may face, Moniem says DuPont is diligent with its testing process. “The process for Nomex, and specifically Nomex used in PPE suits, is one of the best in the world and has set industry standards for testing procedures,” he explains. “We use a burn injury evaluation unit that we’ve named 'Thermo-Man'. It is one of the most advanced life-sized thermal burn injury evaluation devices in the industry and uses state-of-the-art technology to demonstrate the performance of Nomex.”
DuPont has six Thermo-Man testing units around the world and the company is constantly testing using software simulation and Thermo-Man units to develop safer and more comfortable garments that can raise the level of safety and utilisation of the material.
Thermo-Man evaluates the burn injury potential of the materials and measures the performance of the protective apparel. This thermal-testing mannequin is equipped with 122 heat sensors and is exposed to various fire hazards through controlled burns to test burn protection properties of garment constructions, fabric weights, material types and garment design styles. The video demonstration above shows the mannequin being ignited for 20 seconds with flames of 2cal/cm². In the video, the garment made of Nomex does not melt or drip and self-extinguishes, whereas the garment made of polyester continues to burn.
According to DuPont, the data collected in the sensors can predict the amount, degree and location of burn injuries that would be sustained by the wearer in a flash fire. DuPont scientists then use this information to help apparel manufacturers develop optimum designs in lightweight, flame-resistant suits that equip drivers, pit crews, rescue teams and track officials that are comfortable and provide ideal thermal protection.
In addition to the Nomex fabric, Moniem explains that Romain Grosjean’s suit - designed and manufactured by AlpineStars - has incorporated decades of precision garment design that is proprietary to that manufacturer. “Each manufacturer who designs products to meet the FIA safety standards works with DuPont and our value chain partners to design different fabric weaves to construct garments to meet and, usually, exceed these standards,” he explains further. “Some layered suit designs also have features such as quilting air pockets that expand when exposed to heat and that give the driver additional thermal barrier to further delay any burning of flesh.”
Scientists at DuPont taking off burnt clothing on Thermo-Man.
Moniem adds: “Technology and advances in material science worked together during this incident to help save the driver’s life and limit injuries – the racing suit made with Nomex is just one of the elements that contributed to his safety.”
Aside from heat resistance and self-extinguishing qualities, Moniem adds that the material is also lightweight. “There was scepticism from drivers when Nomex suits and layers were first introduced due to concern that it would weigh drivers down, but what this crash illustrated is not only are these materials crucial in keeping them safe in dangerous F1 environments, but they also do not weigh the driver down or stop them from escaping.” Grosjean pushing himself out of the burning car and over the barrier to safety demonstrates this.
Looking forward, Moniem says DuPont’s ultimate aim is to develop materials and technologies that improve performance, safety and comfort while remaining lightweight and durable. He adds that the material can take many forms and has numerous end-use applications. Indeed, as well as being used in PPE, Nomex is also used in aeroplanes; as thermal protection and electrical insulation in hybrid electric vehicles, and in electric infrastructure applications among others. Given the broad range of applications and end-markets, Moniem says the DuPont team is always learning and applying to solve challenges that its customers and end users face.
Moniem also believes that the FIA and F1 will evolve new regulations for racing cars and fire suits in response to the incident in which Grosjean was involved, as they are often quick to respond to new data. “The FIA has announced a full investigation into the incident and it is likely these findings will have a direct impact on what we develop next,” he concludes.
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