Big Bill FR Liner 52 cal/sq cm Arc PPE Category 4 Navy Zipper Closure

Arc-Rated Liner for High-Energy Work

This Big Bill FR liner carries a 52 cal/sq cm ATPV rating and meets Arc Flash PPE Category 4 requirements. It is built for workers who face severe arc-flash hazards and need a certified layer that can be worn beneath an outer shell. The navy 7 oz Nomex construction delivers the required protection without adding a separate heavy garment.

Zip-In Design for Modular Layering

The YKK #5 reversible Nomex-taped Vislon zipper allows the liner to fasten securely inside a compatible unlined bomber jacket. Elastic tabs on the cuffs stabilise the sleeves when zipped in, while the elastic knit collar and elasticised back waist improve fit and mobility. Two large side pockets at the waist remain accessible, and bar-tacking at all stress points reinforces the attachment points.

52 cal/sq cm Protection with Cold-Weather Insulation

The 52 cal/sq cm rating provides the thermal capacity required for Category 4 tasks, giving the wearer a substantial margin against second-degree burn onset. Insulation is integrated for cold conditions, so the liner handles both arc-flash energy and low temperatures in a single layer. It does not replace an outer arc-rated shell where the hazard assessment calls for a complete system.