Quality of analytical results Quality of analytical results Quality of measurements made in chemistry and other areas is an important issue in today’s world as measurements influence quality of life, cross-border trade and commerce. In this respect, EN ISO 17025 is the main standard used by testing and calibration laboratories as to appropriately tackle quality management related issues. While chapter four of the standard deals with management requirements, chapter five describes requirements for technical competence. Management related issues can be found in other standards as well e.g. ISO 9000, however the technical requirements are specific for calibration and testing laboratories. As for technical competence,
Symbols and conventions used in welding documentation Symbols and conventions used in welding documentation The symbols and conventions used in welding documentation are specified in national and international standards such as ISO 2553 "Welded, brazed and soldered joints -- Symbolic representation on drawings" and ISO 4063 "Welding and allied processes -- Nomenclature of processes and reference numbers". The US standard symbols are outlined by the American National Standards Institute and the American Welding Society and are noted as "ANSI/AWS". Due in part to the growth of the oil industry, this symbol set was used during the 1990s in about 50% of the world's welding operations. An ISO