Các đơn vị, tổ chức quốc tế
- ISO - The International Organization for Standardization
- IEC - The International Electrotechnical Commission
- Oiml - The International Organization of Legal Metrology
- Bipm - The Bureau International des Poids et Mesures
- EURAMET - The European Association of National Metrology Institutes
- EUROPEAN STANDARDIZATION - CEN-CENELEC