Durable FR Cotton Blend fabric is made flame-resistant by application of a flame retardant finish. COMBED COTTON. INHERENTLY FLAME RESISTANT. Firewear® is a top contender for petrochemical workers, utility workers and firefighters. Our Fibrous Flame Retardant Fiber (FFR) is inherently flame resistant and selfextinguishing. FR properties are permanent, and will not be damaged through repeated laundering. Click here to learn more about Bulwark Fabric Types.