We design industrial control systems and we have to use Orange wire in accordance with NFPA 79 184.108.40.206. It says "This color identification shall be strictly reserved for this application only". Then you go over to NFPA 70 110.15 and they want me to use Orange on the high leg delta. I am not sure how I can comply with both of these and be in compliance. Orange is also used for 70-424.35 Heating Cables & 517.160(A)(5)(1) Isolated Circuits. Shouldn't these all agree?