Calibration Laboratory • 5 mins read
5 mins read
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In April 1966 the UK took a decisive step towards trusted measurement, creating a national approach to calibration accreditation that would underpin trade, innovation and safety for decades to come. Sixty years on, UKAS carries that legacy forward—helping ensure that calibration certificates are credible, comparable and accepted worldwide.
A national need for confidence in measurement
In the mid-1960s UK industry made a clear case: exporters and manufacturers needed calibration certificates that overseas customers could trust, supported by stronger measurement standards and better training in measurement science. The Minister of Technology, Frank Cousins, proposed a network of approved laboratories—across both public and private sectors—each authorised to issue calibration certificates within a defined scope. The British Calibration Service was born with a remit to assess these laboratories and provide formal recognition of their competence: the foundations of modern calibration accreditation.
The British Calibration Service: setting the pattern
The service quickly put governance and technical expertise at the heart of the new system. Edgar Barnett, from the Ministry of Aviation, was appointed Director and established both a headquarters and the Minister’s Advisory Committee on Calibration and Measurement headed up by Maurice Banks, Deputy Chairman of BP. The committee brought together respected voices from industry, academia and the National Physical Laboratory (NPL) – reflecting an early recognition that measurement is both a practical and a scientific discipline – and set the rules for approving laboratories, strengthening teaching in measurement science and supporting international collaboration.
From the outset, the British Calibration Service introduced concepts that are familiar to accreditation service users today: defined scopes of competence and peer-informed assessment. Early technical panels covered core measurement areas including electrical, mechanical and fluid measurements. Approved laboratories issued certificates bearing the British Calibration Service badge—an early mark intended to signal trust and consistency.
The service also helped bring emerging ideas into mainstream practice—most notably the need to evaluate and communicate measurement uncertainty. By 1968 the first ten laboratories had been accredited, including Coventry Tool and Gauge (accreditation number 0001) as the first mechanical laboratory and Ferranti (0004) as the first electrical laboratory. Laboratories were assessed by a lead assessor from British Calibration Service HQ and a technical assessor from the relevant technical panel. Assessments considered people, facilities and environmental conditions, reference standards and traceability, equipment and documented procedures—principles still central to competent calibration accreditation today.
Over the years the service evolved within government, reflecting both the growing importance of measurement to the economy and the need to keep accreditation close to technical expertise. By the early 1980s the number of accredited calibration laboratories had grown from tens to hundreds, supporting an increasingly diverse industrial base.
NAMAS: aligning calibration with testing and international standards
In 1985, calibration accreditation merged with testing accreditation to form the National Measurement Accreditation Service (NAMAS), part of NPL. Calibration expanded well beyond its original core disciplines, reflecting advances in instrumentation and the widening needs of industry—spanning areas such as optical, thermal, radiological, chemical and acoustics measurement. This chapter in the calibration accreditation journey also saw measurement uncertainty take a more formal place in practice, supported by UK guidance that helped laboratories express uncertainty and confidence in results in a consistent way.
NAMAS requirements were a forerunner of today’s ISO/IEC 17025, helping embed consistent technical and quality expectations across the UK calibration community. As standards evolved, accreditation to this standard moved towards what is now recognised globally as best practice for competent laboratories.
UKAS: one national accreditation body, global recognition
In 1995 the United Kingdom Accreditation Service (UKAS) was formed through the merger of NAMAS and the National Accreditation Council for Certification Bodies (NACCB). For calibration laboratories, this consolidated accreditation within a single national body strengthened alignment with international expectations—particularly as ISO/IEC 17025 became the central standard for demonstrating technical competence.
Over the past 30 years, UKAS calibration accreditation has continued to grow in breadth—from traditional electrical, mechanical and thermal measurements to newer and increasingly specialised areas such as accelerometery, density, dimensional, mass, fibre optics, textile, ultrasonics and volume.
The continuity of our service is also striking: one of the earliest British Calibration Service accreditations—0009, now TÜV SÜD Limited trading as the National Engineering Laboratory—remains accredited today; linking the first decade of the scheme to modern practice.
As calibration accreditation enters its 60th year, UKAS maintains 366 calibration accreditations managed by the Calibration, Inspection and Testing (CIT) Section made up of a Director, five Senior Assessment Managers and 14 Assessment Managers.
These accredited calibration activities support sectors as varied as manufacturing, energy, healthcare, transport, construction and environmental monitoring. Behind each accreditation is the same core aim that inspired the British Calibration Service in 1966: confidence that measurements are traceable, uncertainties are understood and results are produced by competent people using controlled methods.
Accredited calibration laboratories remain a vital part of the UK National Measurement System. They help ensure that everything from routine quality checks to high-stakes measurements in safety-critical industries are based on solid foundations.
Our work extends beyond the UK and we maintain accreditation for customers in many countries including Borneo, China, India and Iceland. As UKAS accreditation is recognised internationally, this helps UK businesses trade with confidence and enables global supply chains to rely on measurement results.
UKAS will continue to provide a comprehensive national – and international – service for the calibration of measuring instruments of all kinds in the decades ahead. This will support innovation in measurement and ensure that confidence in results keeps pace with future technologies, risks and opportunities.