The Bulwark Lightweight FR Long Sleeve Henley is a 5 oz. inherently flame resistant work shirt rated 4 cal/cm2 (CAT 1), built for industrial workers who need breathable upper-body protection for daily field wear. Designed for electrical, utility, and oil and gas environments, this FR henley combines lightweight comfort with dependable CAT 1 arc-rated protection suitable for warm weather conditions and year-round layering systems. This shirt uses a 70% Modacrylic, 30% Tencel inherently flame resistant blend, which means the protection is built into the fiber itself and will not wash out under normal laundering. The 5 oz. weight puts it in the lightweight category, and the crew-style collar and three-button placket give it a henley silhouette rather than a heavier button-front work shirt. This long sleeve FR henley functions as either a standalone lightweight FR shirt for jobs where a CAT 1 hazard assessment applies, or as part of a layered arc flash PPE system when the jobsite calls for a higher combined rating.* The henley collar, ribbed collar and cuffs, and pullover design provide a more casual fit profile while still meeting workplace compliance requirements in industrial and utility settings. *Remember: You cannot add garments’ arc ratings together to determine the combined protection. To get an accurate layered rating you MUST have the test data, and that data must be the same fabrics in the same layered configuration. The garment is certified to ASTM F1506 and ASTM D6413, and it is built for workers who require dependable flame resistant clothing for daily use. Properly cared for, this garment maintains its flame resistant properties for the useful life of the garment. Follow all manufacturer laundering instructions to preserve garment performance and fabric integrity over repeated wash cycles. Compared to heavier FR work shirts rated CAT 2 or higher, this lightweight Bulwark henley supports improved mobility and reduced bulk while still meeting Category 1 compliance requirements. The long sleeve construction adds arm coverage for environments where exposed skin protection is required at the CAT 1 level.