Interlaboratory comparisons

Laboratories are committed to optimum quality of their instruments, procedures and measurement capabilities. To do this, they usually work with internal inspections. However, external validation is indispensable. VSL provides this, in the form of interlaboratory comparisons.

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The importance of interlaboratory comparisons

Systematic measurement deviations that develop over time cannot be detected by internal audits alone. Several accreditations, as well as ISO/IEC 17025:2017, therefore require laboratories to participate in Proficiency Tests (PT schemes) or interlaboratory comparisons. This involves an anonymous comparison of measurement results from multiple laboratories (benchmarking) to identify any deviations. VSL is an accredited PT provider.


Interlaboratory comparisons in practice

During a Proficiency Test, all participating laboratories perform the same measurements and data analyses. The results are compared and compiled into a report in which each participant is assigned a unique code. Participants only know their own code, allowing them to anonymously compare their results with those of other laboratories. We treat the data confidentially and only disclose them to the laboratory itself.

Participation in interlaboratory comparisons is an investment in reliability, operational security and confidence in one’s own capabilities. It also enables laboratories to meet the requirements for accreditation and ISO/IEC 17025:2017.

Laboratories that are committed to quality also consider it important to participate in ILCs (PT schemes) because:

  • they allow them to independently verify and confirm their own performance
  • they provide input for strategic marketing decisions because they show how the laboratories perform compared to others
  • they either confirm the laboratories’ satisfactory performance or provide a warning of possible problems that require investigation
  • the laboratories see PTs as a quality and risk management tool
  • they recognise the educational role of PTs
  • they meet the requirements set by regulatory and accreditation bodies.

Would you like to know more about our services?

Our experts are happy to help.

Peter van Otterloo
Sales Engineer

Planned comparison schedules
VSL carries out interlaboratory comparisons in several areas. These range from pressure, mass and viscosity to temperature, electricity and length. Click here to see the available interlaboratory comparisons.


Need another interlaboratory comparison?
Depending on demand from the market, we can set up interlaboratory comparisons with a diversity of ranges, artefacts and technologies. Another possibility is to organise a bilateral comparison with VSL. Just let us know.

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