It is essential in everyday life we can trust the weighing instruments used in shops, factories and hospitals. Therefore, legal metrology legislation is in place to guarantee the quality of weighing. For centuries rules are set to make sure a customer is able to trust that the indication on a scale is correct. In other words, that one kilogram on the display means the product weighed is in fact one kilogram. Currently, there is a comprehensive legal framework in place consisting of European and national legislation, international standards (e.g. OIML Recommendations) and guidelines (e.g. WELMEC guides) to protect users and consumers. Particularly in the area of commercial transactions, medical diagnoses and legal disputes these requirements are strict and not-negotiable.
Consequently, the weighing instruments need to meet certain standards when being sold and during its lifetime there are rules to guarantee they continue to function correctly. For purchasers it is mandatory to buy the weighing instruments that are compliant with the requirements as set in European Directives when used in specified situations such as commercial transactions. Every weighing instrument type is checked and certified by an independent notified body to guarantee it meets the legal requirements. Depending on the conformity assessment procedure followed, also quality audits are carried out to certify the production process of the manufacturer.
Additionally, weighing instruments are obliged to be checked and reverified by an approved organisation or government body on a regular basis and/or after repairing a weighing instrument. National legislation sets strict requirements to guarantee the accuracy and reliability of weighing instruments during its lifetime. With this legal metrology framework users can rely on business transactions being fair, medical diagnosis being correct, medicines produced according to the highest quality standards and law enforcement appropriate. This way the legal metrology framework protects users, businesses and customers and enables the world to function smoothly.
 Directive 2014/31/EU on non-automatic weighing instruments & Directive 2014/32/EU on measuring instruments