Ionising radiation metrology

Exposure to large amounts of radiation is harmful to humans and animals. Fortunately, radiation equipment is becoming more and more sophisticated. Innovations are only made possible by accurate radiation measurements and correct interpretation of the measurement data.


Ionising radiation

Exposure to large amounts of radiation is harmful to humans. Sometimes this happens accidentally, as in the Fukushima disaster. Conversely, in radiotherapy for cancer treatment, ionising radiation is used intentionally to destroy malignant cells (tumours). Measuring the amount of radiation delivered (dosimetry) and its precise location are two essential factors for successful treatment.

Accurate measurements are crucial to both external (teletherapy) and internal radiation (brachytherapy), Radiation equipment, such as linear accelerators combined with an MRI scanner, is becoming increasingly sophisticated, with proton radiation being applied instead of the traditional photon radiation treatment. VSL is developing measurement methods to determine with increasing accuracy the amount and distribution of radiation delivered by this new radiation equipment.

VSL and ionising radiation

VSL provides various dosimetry services to hospitals, the medical industry, dosimetry companies, producers of radiation equipment and detectors, as well as to parties that work with radiation, such as nuclear power plants. We are also working on several research projects at a European level.

VSL specialists sit on several committees, including the Netherlands Commission on Radiation Dosimetry (NCS), where they advise on the measurement of ionising radiation.

Would you like to know more about our services?

Our experts are happy to help.

Jaïr Blom
Sales Engineer


We support and advise manufacturers and end users with regard to questions, enabling them to improve measurement and inspection methods to optimise the quality of their processes and products.

Custom services

Custom ionising radiation metrology

VSL has specialised knowledge of and experience in ionising radiation as well as in its measurement and the interpretation of measurement data. Governments, hospitals, research institutes and manufacturers regularly ask our help with specific applications. Our services in this regard include:

  • Advice on and set-up of measurement systems. From the design of measurement set-ups and ensuring traceability to the set-up and preparation for ISO certification.
  • Development and validation of measurement methods. This results in a report describing the measurement and validation method, including the determination of measurement uncertainty.
  • Advice with regard to ISO certification. A measurement system must meet several requirements in order to obtain accreditation. VSL verifies the measurement method and measurement data, optimises traceability and calculates the uncertainty budget.
  • Reducing measurement uncertainty and preparing the uncertainty budget.
  • Audits of calibration labs. These are carried out on the instructions of the Dutch Accreditation Council.

Every situation is unique. Do you need advice or would you like to know what we can do for you? Don’t hesitate to contact us.


Ionising radiation calibration services

Accurate radiation measurements are essential to ensure effective radiotherapy treatments and patient safety in radiological diagnostics. VSL ensures traceability to standards in radiotherapy (teletherapy and brachytherapy) by calibrating ionisation chambers for Co-60, Cs-137 and X-ray beams. In addition, we calibrate well-type ionisation chambers for Ir-192 sources.

As regards radiological applications, we calibrate KAP meters, KLP meters and ionisation chambers for a wide range of X-ray qualities. We adhere to the ISO, IEC, NEN and NCS standards.

Keeping radiation environments safe

Radiation levels also need to be accurately measured to ensure the safety of employees in such environments. Quality can be guaranteed by means of regular calibration of the radiation source or measurement equipment. Regular calibration is also a requirement for ISO certification and FDA approval.

On-site calibration of radiation sources

In addition to performing calibrations in its own laboratory, VSL offers on-site calibration of radiation sources. This way, we provide as many high-quality sources as possible.

Our areas of expertise