ISO 8655 is the global standard that defines how Pipettes/POVA (Piston Operated Volumetric Apparatus) devices should be manufactured and tested for accuracy. The standard outlines what types of devices fall under each of the different categories and the different levels of care that are needed to manufacture and test each device. The original document was released in 2002. In May of 2022, the ISO committee released an update to the document with new chapters and changes that will affect all pipette users. In March 2024, ISO 8655 released Part 10: User Guidance and Requirement for Competence, training, and pipette suitability.
The 2022 update made changes to the terminology, specifications, devices, reference methods, and user training.
One of the key changes is to the reference methods and environmental controls in how pipettes are tested. The requirements to perform calibrations are now much stricter and require the right equipment, not only balances but also hygrometers and thermometers, to make sure that all conditions are correct for testing.
Please click here to view our on-demand webinar for a more detailed summary of the changes and updates.
The ISO 8655-10 guideline outlines the importance of qualification and re-qualification of pipette users in the laboratory. Volumetric performance is dependent on the technique employed by the user, and, therefore, proper training and competence assessments are necessary. Besides the users, the pipettes must also be qualified and re-qualified, and part 10 of the ISO 8655 also gives guidance here.
Your work is too important to risk inaccurate or inconsistent data due to poor pipette performance. Rainin pipette service is rigorous and comprehensive, executed by highly trained and experienced technicians who know your pipettes.
As one of the members of the ISO committee, we are uniquely positioned to provide you with all of the solutions that will meet the new ISO 8655 requirements and have implemented changes in our service processes to reflect all the changes.
Whether you prefer mail-in or onsite service, we offer a range of pipette calibration plans that includes the update to ISO 8655 and ISO 17025-accredited calibration to meet your regulatory needs.
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Rainin Good Pipetting Practice™ by METTLER TOLEDO is a practical, science-based approach to helping scientists improve and enhance the accuracy and efficiency of their experiments.
From workflow evaluation and instrument selection to technique, ergonomics, and instrument qualification, GPP helps labs improve experimental reproducibility with an array of training and technical and support resources. The different Rainin trainings cover all topics of ISO 8655-10.
Find more information or to sign up for a seminar here.
The SmartCheck is an easy-to-use device built to perform Routine Tests between calibrations. Routine Tests are introduced in ISO8655:2022 as a simple test to reduce the risk of inaccurate pipetting. SmartCheck can be used with the binary pass/fail decision rule mentioned and combined with PipetteX for complete documentation.
The combination of SmartCheck and PipetteX can also be used to perform and properly document user competence assessments according to ISO8655-10.
Click on the respective links to learn more about SmartCheck and PipetteX.
ISO 17025 provides general standards for testing and calibration labs and maintaining high-quality systems. It focuses on maintaining well-defined processes and tracking and documenting everything around them. A testing house can be accredited to ISO 17025 and follow standards that differ from ISO 8655.
ISO 8655 specifically details requirements for manufacturing and calibrating pipettes and other manual or semi-automated liquid handling devices. Automated liquid handling systems are covered in a separate standard (ISO 23783).
There were many changes, but the most relevant include:
a. Updates to the volume specifications for a POVA. Each now has its own specifications, which in some cases are tighter than the 2002 version and cover a wider volume range.
b. New specifications for syringes and multichannel pipettes.
c. New recommendations for routine testing between calibrations.
d. New terms or clarifications of terms that reflect best-practice metrology definitions.
• Part 6: Gravimetric reference measurement
This section specifies the procedure for determining the volume of a POVA using the gravimetric method, considered one of the gold standards for calibration. It defines strict requirements around equipment, pipette environmental conditions, and the number of test readings. Deviations are not permitted.
• Part 7: Alternative measurement procedures
This section specifies alternative procedures for determining the volume of a POVA, including gravimetric, dual-dye photometric, single-dye photometric, photometric/gravimetric hybrid, and titrimetric procedures.
It also describes potential exceptions to the procedures stated in Part 6.
• Part 8: Photometric reference measurement
This section specifies the procedure for determining the volume of a POVA using a dual-dye photometric reference method. It is considered another gold standard or preferred calibration procedure.
Part 6 follows the gravimetric method, considered one of the best methods for pipette calibration according
to ISO’s 2022 standard, whereas Part 7 provides several alternative methods. Also, Part 6 includes the following requirements and, unlike the 2002 standard, does not allow for deviations:
• Number of measurements
A minimum of 3x10 measurements is required (the 2002 standard allowed testers to claim conformity with less than 10 measurements). The three volumes tested must be 10%, 50% and 100%. If a pipette’s minimum volume range is greater than 10%, that volume can be tested.
• Room temperature
The testing room temperature may only vary by ±0.5 °C while testing, and the equipment must be given time to equilibrate.
• Water temperature
The difference in temperature between water and air must not exceed ±0.5 °C. The water temperature must be recorded at the beginning and end of calibration and printed on the certificate.
• Tip changes
Tips must be changed after five dispenses. For example, in a 3x10 calibration for a single-channel pipette, a technician must use six tips (two for each test volume).
Part 7 provides several alternative methods, including a modified gravimetric method that has less strict environmental control requirements, thus making it easier to perform calibrations onsite. Rainin Service lists specific requirements in our standard method document, PS-125. For laboratories who desire ISO/IEC 17025-accredited work that is not strictly ISO 8655 Part 6 compliant, we recommend calibrating according to Part 7.
Products and technologies have changed in the 20 years since the original version was released. The update also includes new procedures and techniques used to test a POVA, e.g., the photometric method was added as a gold standard. The new standard also emphasizes the role of the end user and the standard operating procedures required to perform calibrations and routine maintenance and includes updates to metrology (including terminology, uncertainty calculation, and routine testing).
It is a substantial improvement if users change from four to 10 measurements. The uncertainties calculated for each volume are lower and it reduces your overall risk and improves the quality of your calibration.
When you take calibrations with 10 measurements, you have a higher confidence that the results you receive are within a 95% confidence interval. Once you reduce the measurements to less than 10, you increase the chance you may have a result that is outside of the specification. One must take this risk into consideration when choosing between four or 10 measurements.
Laboratories need to determine their requirements for following the new ISO standard.
Some laboratories may be audited by agencies or companies requiring strict adherence to the new standard. If so, they may need to update their standard operating procedures to match changes in methodology. Laboratories in GMP- or CLIA-type regulated environments or who work for other companies in these environments may need to follow ISO 8655 guidelines as they reduce the risk of instruments not performing to specification.
Laboratories in research and academic environments that do not use accreditation services can continue to have their pipettes calibrated without change. If laboratories still want accreditation but want to avoid the stringency of Part 6, they can use Part 7.
Because the usage of POVA, especially pipettes, can be very user-dependent. This applies not only to the pipetting techniques or skills but also to the selection and qualification of the POVA (e.g., pipettes) and exchangeable parts (e.g., pipette tips).
The new Part 10 of the ISO8655:2022 focuses on the Pipette (POVA) user.
Besides best practices for using POVAs, it includes a section on the selection and qualification of instruments and the respective consumables.
As user skills can greatly influence pipetting user qualification, Part 10 introduced regularly scheduled training and user competence assessments.
ISO 8655 Part 10 divides user qualification into training and competence assessment. Every user will be regularly trained and retrained in pipetting.
Rainin´s GPP program covers training in all aspects of pipetting. User skills can be assessed yearly. With Rainin´s SmartCheck and PipetteX, user skills can be evaluated directly in the lab.
Different performance requirements, calibration frequencies, routine test frequencies, and pass/fail decision rules help establish a fitting POVA qualification process. Other possibilities for planning a quality assurance process are described. Rainin can help here with different solutions to fulfill the requirements.
The uncertainty in use describes the overall accuracy consisting of the systematic and random error and a coefficient covering the number of measurements. The Safe Pipetting Range describes the volume range with uncertainty in use and a safety margin below the liquid handling tolerance. More details can be delivered in a GPP seminar.