What are the criteria(s) to make these changes? Are there regulations and policies? If so what? Please provide guidance.
As you know, Source, Maintenance and Recoverability (SMR) codes are used to identify the origin of spares, repair parts, and end items of support equipment, and the maintenance authority to use, maintain, overhaul, rework, rebuild, condemn, or dispose of them. Your question asked for guidance on SMR changes, over concern regarding Beyond Economical Repair (BER) decisions, and such concern is appropriate since both initial code assignment and subsequent changes to SMR codes significantly impact funding appropriations, requirements determination, and each of the 12 integrated product Support Elements (IPSE). The overarching reference for development and use of SMR codes in DOD is the AR 700–82/SECNAVINST 4410.23/AFMAN 21–106, Joint Regulation Governing the Use and Application of Uniform Source, Maintenance, and Recoverability Codes, (http://www.navybmr.com/study%20material/SECNAVINST%204410.23.pdf).
Individual Services typically have varying processes for managing and changing SMR codes. For example, within the bounds of the joint processes mentioned above, the USAF SMR code change procedure details use of USAF Tech Order Form 22, per TO 00-5-1 and TO 00-25-195. Comparable Navy/USMC procedures are in the NAVSUP P-719/NAVSUPINST 4423.29, Navy Uniform Source, Maintenance and Recoverability (SMR) Codes, (http://www.navybmr.com/study%20material/NAVSUPINST%204423.29.pdf) which provides DON unique procedures. That reference discusses forms, request procedures and content, and routing processes. Chapter 10 includes change procedures for organizations under purview of NAVAIR, and Chapter 11 covers change procedures for NAVSEA, SPAWAR, etc. I could locate no Army-specific documents describing the process – available documentation refers back to the joint instruction which provides overarching evaluative rationale for code changes, but it does not detail USA processes. Keep in mind for that for each of the Services, such decisions most likely originate within and generally are the purview of the program office, based on Product Support Business Case Analyses (BCA), Level of Repair Analyses (LORA), maintenance planning and the development/ongoing evolution of the product support strategy as a system matures and changes over time. It is clearly the role of the program office to determine (and periodically reevaluate) optimum maintenance, repair, and disposal options for system components, and likewise, for subsequent SMR changes, as the product support strategy and maintenance plan changes. The economics portion of your question is one of many inputs to those decisions, although cost does not in itself drive consumable vs repairable characterizations. With a systematic, fact-based justification for requested SMR changes, your provisioning office at the serving Inventory Control Point, would take the lead on incorporating such changes once the program manager/Service decision is made.