Rationale

T.G. 428. Tube Marking. A) A solid quality control system has to rely as a very first step on tracking and traceability up to the maximum practical extent. B) An "anonymous" good does not assure Customer and Contractors for quality and product liability and does not even protect the manufacturer. C) Establishing solid product liability is crucial while industry is moving towards the application of hazardous and flammable refrigerants. D) (important) ASTM B1003 is specific standard for linesets. Provided the main field of linesets application, it is well accepted the intimate connection between ASTM B1003 and ASTM B280. Thus, extending marking on tubes in B1003 would grant the above-mentioned consistency and consolidate a common ground within the industry. E) (very important) UL 207 (Rev. Aug. 26, 2022) --Refrigerant-Containing Components and Accessories, Nonelectrical-- says that <> F) In this draft I added the option to mark the copper tubing by ink to address the comments related to the concerns on the connection with the fittings. I used the wording "shall be permanently incised or marked by ink" since the wording "permanently marked" does not have a punctual meaning at the moment.