Principali enti normatori

 - API – American Petroleum Institute
 - ASA – Acoustical Society of America
 - ASHRAE – American Society of Heating, Refrigerating & Air Conditioning Engineers
 - ASME – American Society of Mechanical Engineers
 - ASTM – American Society of Testing & Materials
 - AWWA – American Water Works Association
 - BS – British Standards Institution
 - DIN – Deutsches Institut für Normung
 - IEEE – Institute of Electrical & Electronics Engineers
 -  IET – Institution of Engineering & Technology
 - IP – The Institute of Petroleum
 - ISO – International Organization for Standardization

 - NFPA – National Fire Protection Association
 - SAE – Society of Automotive Engineers
 - UNI Ente Nazionale Italiano di Unificazione
 - VDE – VERLAG Conference Proceedings