You can focus on the job, because we've focused on the details. Wrangler FR® garments are designed to self-extinguish to effectively prevent or greatly reduce the severity of burn injuries and were created to meet the rigorous requirements of the major protection agencies. HRC 1 and meets ASTM 1506, NFPA-70E and OSHA Final Rule 1910.269. he RIGGS WORKWEAR® flame resistant long sleeve denim shirt offers a relaxed, comfortable fit. 7.5 oz. 100% Cotton FR twill. Flap front pockets with pencil slot. Safety orange outside ID for high visibility. Size selection varies by retailer. Check with your local/online retailer for availability.