What does "Inherently flame retardant" mean?

Cheaper flame retardants only have a limited life because the treatment that makes them flame retardant will eventually wash out.

Inherently flame retardant materials like Protal & Protex means they are flame retardant for the life of the garment.

Made from Protal fabric (although some garments will have the Protex logo on.

Concealed front button fastening with zip fly.

Two side hand pockets with same material lining.

Two leg cargo pockets with fixed flap.

Belt loops.

Flame retardant ENISO11612 A B1 C1