Legal metrology

The food we consume, the tap water we drink, the electrical appliance we switch on, the car we drive, the airplane that transports us — in all these situations, our safety depends on the application of safety laws and regulations developed and implemented by authorities, regulatory bodies, and governments. The purpose of these safety laws and regulations is also to ensure that the information displayed on labels, packaging, and user manuals is accurate.

Regulations may:

  • establish tolerance thresholds to protect us against the ingestion of different kinds of toxic substances in food (such as heavy metals, pesticides, and harmful bacteria),
  • specify the materials that may be used for water pipes (for example, lead-free materials),
  • limit the amount of electromagnetic radiation emitted by electrical devices (such as household appliances that create interference with radio or television receivers),
  • specify testing requirements applicable to motor vehicles in order to ensure compliance with road safety standards (for example, the CO content of exhaust emissions).

There are countless practical examples demonstrating the vital importance of accurate measurements for our safety: from the compatibility of electrical equipment to the control of medical devices and instruments, as well as the composition of construction materials, and much more.

SAFETY: A RIGOROUS MEASUREMENT SYSTEM

A rigorous measurement system is essential for achieving an effective safety policy. The key factors of such a system are:

  • traceability to the International System of Units, or SI (scientific metrology),
  • regulations concerning measurements and measuring instruments (legal metrology), and
  • confidence in testing and measurement results through certification, standardization, accreditation, and calibration (industrial metrology).

At the international level, national measurement systems must be compatible and harmonized, while mutual trust and mutual recognition arrangements are indispensable.

The International Bureau of Weights and Measures (BIPM) helps coordinate arrangements and maintains international reference equipment designed to ensure the comparability of the many national measurement standards established by national metrology institutes.

The International Organization of Legal Metrology (OIML), together with national legal metrology authorities, works on developing harmonized regulations concerning measurements and measuring instruments used to guarantee safety.

The International Committee for Weights and Measures (CIPM) and the OIML have respectively established a Mutual Recognition Arrangement (CIPM MRA) and the OIML Certification System (OIML-CS), which serve as frameworks for demonstrating the consistency of measurements and tests at the international level.