Nomex Underwear Medium SFI

The RJS Safety Nomex Underwear Medium SFI is a two-piece fire-resistant base layer engineered for high-temperature environments and motorsport applications. Constructed from Nomex—a aramid fiber fabric proven to resist ignition and self-extinguish—this underwear set meets SFI 3.3 certification standards, the recognized benchmark for motorsport safety apparel. The long-sleeve top and matching bottom work together to provide comprehensive thermal protection while maintaining breathability during extended wear.

Nomex fiber begins to decompose around 370°C without melting or dripping, characteristics critical for drivers, pit crew, and other professionals exposed to fire hazard. The crew-neck design allows layering under racing suits or proximity gear without bulk, while the white colorway helps with visibility in pit environments. SFI 3.3 certification indicates this garment has passed standardized flammability testing and continues to meet the specifications required for sanctioned motorsport competition and professional racing programs.

This product is designed for professional motorsport participants, fire service personnel, welders, and others working in environments where conventional fabrics present unacceptable thermal risk. The medium sizing and two-piece configuration allow precise fit adjustments under race suits or protective overalls. Nomex base layers function as a critical layer of defense in multi-layer thermal protection systems, not as standalone protective equipment.

SFI-certified base layers are mandatory or strongly recommended in sanctioned racing, professional welding, and firefighting contexts. Nomex remains the industry-standard material for this application due to its proven performance record and consistent certification compliance across manufacturers.