Do you feel someties lost when dealing with metrology experts ? It feels hard to you to find the right consultant that may elp you in your lab metrologic journey .

Christophe Balichard, responsible for the LABELIANS smart service metrology laboratory sits at your side to reveal you all secrets about metrology. Everything you have ever wanted to know about it is just one read away :

Metrology word root

The word” metrology” comes from the ancient greek word “metron” that means measure and “logia” that means science. Metrology is thus the science of measure.

Metrology orgins

Metrology is NOT the last scary thing, invented to fool lab quality professionnals during annual quality processes reviews. Metrology usage is a one of those you really want to put in place and it’s very valuable for anybody who actually fancy being able to repeat an action chain to manufacture a product or master any industrial or wordcraft process.

Since antiquity, measure us is obvious: ” Measure is in everything, and willing to capture it is the first of the sciences” quoted Themistocle ( an Athenian politician, -524/-459 bef. JC). Time measure to organize days, to manage seasonnality, distances to organize space or being able to build, weight measurement to guarantee equal business for all.

International metrology streamlining

The World Trade Organisation made it necessary to standardise measurement units at an early stage. The Metre Agreement was the second international harmonisation agreement after the Telegraph Agreement (ITU in 1865). First communication, then trade. It was held in Paris at the Pavillon de Breteuil on 20 May 1875 and brought together 17 signatory states (Great Britain was obviously not included).

It was on this occasion that the BIPM (Bureau Internationale des Poids et des Mesures), the highest international authority on metrology, was born to coordinate the various actors in this field. This is how the International System of Measurement (SI) came about.

You can also find the International Vocabulary of Metrology guide at the BIPM.

systeme internatoonal des mesures les 7 unités de base

Today metrology management


OIML (International Organization of Legal Metrology)

This is an intergovernmental organisation that internationally co-ordinates and aligns the administration, instruments and measurement techniques of different countries.


ILAC (International Laboratory Accreditation Cooperation)

This international organisation brings together the various national accreditation bodies for calibration laboratories, testing laboratories, medical analysis laboratories and inspection bodies.

The aim is to create an international network to combat technical barriers to trade.


COFRAC (Comité Français d’Accréditation)

The only French authority that can deliver accreditations to organizations involved in conformity assessment in France.

Logo EA

EA (European Accreditation)

It is the European organization that coordinates the various bodies responsible for issuing accreditations in Europe.

Logo LNE

LNE (Laboratoire National de métrologie et d’Essais)

It is the reference laboratory for metrology in France.

Logo CFM

CFM (Collège Français de Métrologie)

This association gathers 680 members and thus makes it possible to disseminate information related to metrology to all the actors.

Measure uncertainty

Metroly experts challenge is not deploying a measurement process or the corresponding tools or means, but rather to consider the measure uncertainty that guarantees the highest confidence level in the delivered result.

The GUM guide is by the way referring tothe sepcific wording of measure uncertainty

5M method may help for uncertainty evaluation :

  • Material or Means represented by the calibration devices
  • Material or Measurand for everything that can influence the measurement: mismatch, instability, stray currents…
  • Manpower for everything related to the operator taking the measurement: his clothes, manual tightening, heat emitted…
  • Method that may differ from the standard method
  • Environment in which the measurement is taken: temperature, relative humidity, vibrations…
loi de propagation des incertitudes avec covariance

Law of uncertainty propagation with covariance

intervalle de confiance par facteur d'élargissement k

Confidence interval / widening factor k

justesse et fidélité instrumentale

Accuracy and instrument integrity

What are companies expressed needs and duties ?

Commercial transactions

Metrology is all around us: the pump at the petrol station, the scales at the vegetable shop or post office, on our roads (speed cameras), taximeters, etc. A whole range of commercial activities are subject to the legal framework of metrology by the States, coordinated by the OILM in order to allow the guarantee of fairness of transactions (evaluation: inspection section of COFRAC in France). The frequency of verification inspections is imposed.


Medecines manufacturing falls under legal metrology thus within OIML perimeter.


Biological analysis When accreditation is compulsory to carry out an activity, the implementation of a metrological management may become compulsory due to the requirements of the standards. We are not in the context of legal metrology, so it is up to the laboratories to implement an adapted metrology in order to guarantee traceability to the international system.


The implementation of a metrological management system may be required to obtain labels (certification) or to meet customer requirements. It is a formidable tool for controlling the quality and conformity of production, the safety of installations and personnel, and the confidence of its customers.

What are metrological solutions for laboratories available on then market ?

There are so many of them , and there are some many rules to follow. For instance you need to run regular machines, micropipettes, or scales calibration.

This is why it’s vital for laboratories to have the support of a true expert in that field.

Maintenance technicians also metrology experts are part of LABELIANS smart service team. They will calibrate your instruments properly for accurate relsults.