The present report aims to address the topic of robustness of instruments and equipment to extreme environmental conditions issue. We are interest to define standard test methods suitable to the specific activities of ENVRI RIs. In this sense, attention need to be devoted not only to commercial instruments, but also to technical solutions often adopted to adapt commercial and/or custom instruments to the extreme environmental conditions in which they will be deployed and will operate. In this report, for our scopes, the concept of extreme environment/conditions is always intended in a very broad sense. First two chapters are mainly devoted to provide a brief but exhaustive introduction about the concept of standards and actual landscape of international as well as national organizations, normative panorama and ongoing tendency arising from rapid technological transformation and global economy. We focus on technical standards, from definitions until description of the whole tailoring process needed to be implemented to carry on in a correct way standard test methods for ruggedness. About this process, Chapter 3 is devoted to describe the typical life cycle of instrumentation operated by RIs of different domains. Based on an analysis of technical standards available for robustness (chapter 4), four standards have been identified to provide necessary information and standard procedures for scope of ENVRI RIs. They are MIL-STD-810G, NF-X 10-812, IEC 60068 and IEC 60259 (IP code). These standards, briefly described in Chapter 4, are considering different environmental parameters and induced effects, providing for all of part of them standard test methods. They group test methods into categories, and, when necessary, include guidelines and suggestions on how to fix or control other environmental parameters affecting the results. For the scope of this Report, categories provided by selected standards have been revisited considering usual environmental conditions in which ENVRI RIs operate, determining a comprehensive list of 24 categories (environmental condition in which we are interested) spanning from cold to low pressure/altitude, from icing/freezing rain to immersion/temperature shock, from corrosion to sand and dust. Categories provided by single standards have been, sometimes merged into a broader category, when necessary retaining only some of proposed test methods. New categories and groups of test methods have been created with the scope to be more compact and suitable for ENVRI RIs and serve more than one environmental domain (Chapter 5). In addition to that, we provide recommendations, as well as illustrate an alternative approach for the most classical and expected harsh environment, polar regions (Chapter 7), and we also illustrate (Chapter 6) how resources and facilities for testing robustness and qualify instruments/systems are not only provided by the private sector, but also inside the ENVRI RIs community, sometimes also supported by EU. Finally, in chapter 8, the issue of implementing a dedicated service is addressed through a sustainable approach based on several steps.