GASCO (Abu Dhba Gas Industries Ltd) commenced design and construction of processing facilities since 1978. The main plants and subsequent expansions were engineered in phases by different EPC Contractors. Piping Material Specifications (PMS) were developed for each Project as per EPC Contractor’s engineering understanding and as per the Project need. This resulted in having different PMS for similar fluid services in an identical process Units/Trains. This paper presents the outcome of the study to optimize the number of PMSs and generate a common PMS to satisfy all the existing plant requirements. GASCO has around 800+ Piping classes across all the sites. The selection of right PMS was a challenge during the modification projects in existing plants. It was also difficult for Store/Ware house personnel to maintain the inventory and track spares as because of large number of stock codes. A comprehensive study was undertaken to develop a master set of PMS involving following steps; data collection & review, checking the compatibility with latest Codes and Standards, study lessons learnt, generate back up calculations, documentation and publish the Design General Specification (DGSs). Through this comprehensive study, 800+ piping classes were optimized to 150 number of piping classes in a common PMS to suit overall GASCO’s requirement. The co-relation of existing piping classes having outdated materials with newly developed classes made the selection of required piping class much easier and user friendly. The new PMS, with new material classes ensuring good engineering practices and adapting the lessons learnt over the years of operation. This optimization campaign facilitated GASCO to formulate a definitive approach towards the selection of common piping material for specific fluids across the plants. The new PMS has segregated the material requirement for various fluids with different operating temperature and pressure conditions from different Units/Trains. Some of obsolete components had been taken out from PMS based on GASCO’s operating experience over last 30+ years. The selection of material has become easy at all level of work force when doing the modification work. Use of right piping material will save material cost with engineered material solution with minimal failures. Alignment with all the Plants with common piping classes will maintain optimum inventory across GASCO plants. The same philosophy can be used within all the OPCOs under ADNOC directives of cost saving and standardization.