1. INTRODUCTION Piping is the most common component in a construction site which is used to transport fluids. Since several de- cades the importance of this component became crucial and for that several standards from ASME, ASTM, ISO, API, BS, DIN, and others, have been published to cover the re- quirement of piping including raw materials, design condi- tions, system design, grades, rating, fittings, joints, flanges, accessories, testing, inspection, installation, commission- ing, operation, maintenance, and rehabilitation. Standards could be a design code which is having several categories (design conditions, pressure design, flexibility and stress intensification, material, standards, fabrication and assem- bly, inspection and testing) like ASME B 31.1, B31.2, B31.3, ISO 14692, or it could be a piping specification document like ASTM D 3517, BS 5911. Other standards could be an auxiliary document related to testing, inspection, installa- tion or other. [1] GRP Glass Fiber Reinforced Polyester material as one of piping materials and due to its versatility it is used in sev- eral applications and services like gravity, high pressure, low pressure, seawater, potable water, irrigation, industrial waste, cooling water, wastewater, circulating water, sewer, firewater, above ground, underground, on ground, subsea, ducting and more applications. In this paper, we will highlight the shared requirement of GRP piping with other materials, and then we will demon- strate the special requirements of GRP piping which make it unique from other materials. We will explain several failure modes for GRP piping some case histories including root cause analysis of several failures. 2 PIPING REQUIREMENT (GRP VS OTHER): 2.1 ER, CHEMICAL WASTE, WASTEWATER): GRAVITY SEWER/ DRAINAGE UG (SEW- In gravity application, the client needs to construct pipe which can handle at least the below requirement: • Availability of piping material with all components and • accessories. Long design life, (50 – 100 years) with lower mainte- nance cost • Minimum leakage and infiltration incidents which are • • and environmental impact also. Good corrosion resistance internal and external includ- ing biological and gaseous medium. Smooth vs rough surface, which will have an impact on pipe sizing for gravity flow. • High abrasion resistance to water jet cleaning • External load resistance at short term and long term RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 59 • Adapting to special design conditions like road crossing, shallow depths, high wheel load, water table, settlement. [2] GRP pipes dominate the best choice material for above service and here is the proof: 1. Design proof: GRP pipes design has been done con- sidering long term behavior as per ASTM D 3681 where pipes are over deflected along with Sulfuric acid solu- tion which is a case simulating a gravity sewer, Amiblu R & D facility has performed a type test results up to 30 years as stated by Mr. Hogni in his interview. Refer to figures 1 and 2. Figure 1: Strain Corrosion Test Amiblu Center [3] Figure 2: Test data for Hobas and Flowtite Pipes for 40 years, results extrapo- lated to 150 years. [3] 2. Flexibility vs Rigidity: GRP considered unique ma- terial between flexible (PVC, PE) and Rigid (RC, VC). Rigid pipes fail by cracking mode under ring bending loading, unlike flexible pipes that are deforming in a deflected mode. Dieter Scharwächter consulting ex- plained the difference between flexible pipe and rigid pipe in buried condition, rigid pipe is more rigid than the soil and it bears the burden of external loading due to soil movement, water table fluctuation, settlement