Hamilton ISO 17034-Certified Liquid Solutions
ISO 17034‑Certified calibration solutions: Precision you can trust for pH buffers and conductivity sensor calibration.
Calibrating Hamilton Probes
Many factors influence the accuracy of sensor measurements, but calibration stands out as the most critical process step, poor or incorrect calibration can lead to inaccurate results, increased waste, compliance issues, and costly process downtime.
Calibration is highly dependent on the buffer solutions used, which are essential for both accurate sensor calibration and verification. Key factors include certified high-quality buffers, proper sensor handling, temperature compensation, defined acceptance criteria, and thorough documentation
To ensure reliable performance, Hamilton complements its sensors with a comprehensive portfolio of best-in-class pH and ORP buffers, as well as conductivity standards.
What role does the ISO 17034 certificate play in defining a reliable calibration solution?
ISO 17034 defines the requirements for organizations that produce certified reference materials. In the context of calibration solutions, it ensures that reference values are assigned using validated procedures, supported by documented measurement uncertainty, traceability to recognized standards, and verified homogeneity and stability over the stated shelf life. This provides a transparent and defensible basis for calibration in regulated and measurement‑critical applications. Beyond these standards, understanding how pH buffer solutions are used for sensor calibration is vital for ensuring the accuracy of your measurements.
What defines a good calibration solution?
- Chemical Properties: Stability & Homogeneity
- Metrological Quality: Known Uncertainty, Traceability & Regulatory Standards (ISO)
- Practical Criteria: Portfolio Range, Shelf Life, Ease of Use
- Operational Reliability: Reproducability, Supply Security, Lead Time, Metrology Competence of Supplier
Hamilton's Sensor Calibration Solutions
ISO 17025 and ISO 17034 Certified Reference Materials
Hamilton is committed to providing products and services that customers can rely on, trust, and use with confidence every day.
This is why our buffer production is based on internationally recognized ISO standards. ISO 9001 certifies a company, ISO 17025 validates testing, whereas ISO 17034 validates the reference.
Our buffer production is based on internationally recognized ISO standards. Our ISO 17034 accreditation, granted by the Swiss Accreditation Service (SAS), demonstrates that our ISO 17034-certified reference materials are produced under rigorous quality control, with traceability and reliability built into every step. The production of these materials requires an unbroken chain of comparisons to primary reference materials of the highest metrological quality, such as those provided by NIST and PTB.
The measurement laboratories are accredited according to ISO 17025 by DAkkS or DANAK. These accreditations provide documented assurance that your calibration standards are fully traceable, compliant, and audit-ready, strengthening regulatory confidence and simplifying verification processes.
What is an ISO 17034 certified reference material?
An ISO 17034 certified reference material is a reference material produced by an accredited organization, with one or more property values assigned, documented measurement uncertainty, and established traceability to recognized standards. ISO 17034 focuses on the quality and reliability of the reference material itself, rather than the calibration laboratory using it.
What information is provided in an ISO 17034 certificate?
An ISO 17034 certificate of analysis typically includes the certified value, associated measurement uncertainty, traceability information, batch identification, and references to applicable standards. This documentation supports the use of the calibration solution in regulated environments and provides transparency for audit and validation purposes.
Benefits of ISO 17034 Certified Reference Material
ISO 17034 is the highest international standard for organizations that produce reference materials, such as pH buffers and conductivity standards.
| What happens on Hamilton's side | ISO 17034 benefit |
|---|---|
| Full traceability and process control | Audit readiness & regulatory confidence |
| Stringent tests throughout the entire shelf life | Lifetime stability guarantee |
| External verification | Defined measurement uncertainty |
| Validated documentation | Enhanced CoA for pharma QA |
Homogeneity for ISO 17034 Certified Reference Material
The homogeneity studies were performed in all packaging materials in compliance with ISO 33405:2024. Homogeneity is assessed using a representative number of samples packaged in their primary packaging, selected systematically across the entire batch to evaluate the between-unit(bottle) homogeneity. All measurements were carried out in compliance with ISO/IEC 17025:2017.
Stability for ISO 17034 Certified Reference Material
Stability studies were conducted for all packaging materials in compliance with ISO33405:2024. The stability assessment covers both the long term stability behavior of the CRM under the recommended storage conditions and the short term stability, which accounts for any additional effects arising during transport and opening of the products.
For a deeper dive into maintaining stability and managing temperature effects, check out our article on properly handling calibration solutions.
Uncertainty Calculation for Certified Reference Material
The expanded uncertainty UCRM for the product is calculated according to ISO 33405:2024 as 𝑈𝐶𝑅𝑀=𝑢𝐶𝑅𝑀∗𝑘, where 𝑘 is the coverage factor for a 95 % coverage probability and 𝑘=2.
uCRM = √( uCharacterization2 + uHomogeneity2 + uStability2 )
The standard uncertainty uCRM is calculated from the root mean square (rms) of uncertainties of characterization, homogeneity, and stability. For instance, the accuracy and stability of conductivity standards are influenced by unique matrix effects that must be accounted for in the total uncertainty budget.
The uncertainty of stability is further calculated by the short-term and long-term uncertainties:
uStability2 = uSts2 + uLts2
- 𝑢𝐶𝑅𝑀 Denotes the standard uncertainty associated with the property value of the CRM.
- 𝑢𝐶ℎ𝑎𝑟𝑎𝑐𝑡𝑒𝑟𝑖𝑧𝑎𝑡𝑖𝑜𝑛 This standard uncertainty is in accordance with ISO/IEC 17025:2017 which includes the standard uncertainty contributions of the primary reference material and the measuring system.
- 𝑢𝐻𝑜𝑚𝑜𝑔𝑒𝑛𝑒𝑖𝑡𝑦 This standard uncertainty is the unit-to-unit variation and is in accordance with ISO 33405:2024.
- 𝑢𝑆𝑡𝑎𝑏𝑖𝑙𝑖𝑡𝑦 This standard uncertainty is obtained from stability studies in accordance with ISO 33405:2024. The stability studies define the minimum shelf life of the respective conductivity standard for unopened bottles, where usts denotes the standard uncertainty contribution from the assessment of short-term stability, and ults denotes the standard uncertainty contribution from the assessment of the long-term stability under storage conditions.
Characterization
The batch was characterized in a laboratory accredited to ISO/IEC 17025:2017. The approach of characterization complies to characterization strategy a) according to ISO33405:2024(chapter 7.12.3). The principle of measurement is based on electrical resistance spectroscopy in a measuring cell with a known cell constant under constant temperature conditions.
Traceability of Hamilton Liquid Solutions
Hamilton works with circular traceability, providing unique reliability
Hamilton relies on two ISO/IEC 17025:2017 accredited laboratories to ensure ISO 17034 metrological traceability. These laboratories are either accredited by DANAK or by DAkkS.
Calibrations performed under DANAK accreditation no. 255 are carried out by Denmark’s national accreditation body, operating in accordance with EU Regulation (EC) No. 765/2008. Alternatively, calibrations performed under DAkkS accreditation no. DK 15186-01-00 are carried out under Germany’s national accreditation body, also operating in accordance with EU Regulation (EC) No. 765/2008.
Calibration results are traceable to national or international standards through reference materials or instruments with documented calibration chains.
As signatories to the EA and ILAC Mutual Recognition Arrangements (MRAs), calibration certificates issued under both DANAK and DAkkS accreditation are internationally recognized by other MRA member bodies.
What are Bottom-Up & Top-Down traceability?
Top-Down Traceability
Top-down traceability refers to the classical calibration hierarchy, where measurement traceability is established by transferring values from national or international primary standards down through a documented chain of calibrations to the end-user instrument. Each step in this chain ensures that the measurement system remains aligned with internationally recognized standards, guaranteeing consistency and comparability of results.
Bottom-Up Traceability
Bottom-up traceability is an uncertainty-based approach where the evaluation starts from the measured value and its associated measurement system. All relevant sources of uncertainty, such as instrument performance, environmental influences, repeatability, and reference standards, are individually quantified and combined to derive the total measurement uncertainty. This method follows the principles of the ISO GUM framework and focuses on building the uncertainty budget from the measurement result upwards.
Related Content
- Download our Liquid Solutions Brochure to see the entire conductivity standard product offering.
- Visit our Main Calibration Knowledge Base Page to see all articles on calibration solutions.