Learn how to be an AASHTO lab 24/7

"“…if you do everything that the AASHTO accreditation requires you to do, if you execute all of the requirements of [AASHTO re:source], you will have a well-run laboratory."

Florida Department of Transportation

Tim Ruelke, P.E., Director, Office of Materials

55+ years of experience
PSP participants
samples shipped per year
laboratory assessments per year
accredited labs

AASHTO re:source ISO/IEC 17025 Assessment: What to Expect and Tips to Prepare

By Guest Author: Jayanth Kumar Rayapeddi Kumar, P.E., Quality Control Engineer, Jas. W. Glover, Ltd.

Posted: September 2023

After having spent about 10 years in developing and deploying a Quality Management System (QMS) conforming to ISO/IEC 17025, AASHTO R 18, and ASTM quality standards, I take this opportunity to share my thoughts about the uniqueness of ISO/IEC 17025 (General requirements for the competence of testing and calibration laboratories) and present some tips about preparing for the ISO/IEC 17025 assessment.

ISO/IEC 17025 is a global quality standard for testing and calibrating laboratories. Conformance to this standard is widely recognized as meeting a higher-level international standard in lab accreditation. The current release was published in 2017. A QMS developed to conform to the requirements of ISO/IEC 17025 will have to factor two distinct differences compared to all other AASHTO and ASTM quality standards.

First, ISO/IEC 17025 is not an industry-specific standard. Therefore, the different requirements listed in the standard are somewhat less prescriptive compared to the other quality standards mentioned previously. For instance, AASHTO R 18 includes frequency of calibration for all lab equipment. The ISO/IEC 17025 does not impose any time frequency for lab equipment. It gives the labs enough latitude to establish an equipment calibration program to maintain confidence in the status of calibration.

Second and perhaps the most important difference is that the ISO/IEC 17025 standard emphasizes risk-based thinking when developing policies, procedures, and programs. It requires labs to proactively evaluate risks and address them in their lab operation. For instance, test results determined by two different technicians in the same lab have inherent variability. Based on the test data, the person in charge of the lab must evaluate if the inherent variability rises to the level of risk. In such a case, the lab must evaluate the risk, its impact on previous results, and rules for resumption of work. AASHTO R18 does not have such a requirement.

A good resource to understand the differences between AASHTO R 18 and ISO/IEC 17025 standards can be found in the Comparison of AASHTO R 18-18 and ISO/IEC 17025:2017. Similar tables showing the differences between other quality standards and ISO/IEC 17025 can also be generated.

ISO/IEC 17025 Assessment and TipsISO-IEC 17025 Assessment- What to Expect and Tips to Prepare

A Construction Materials Testing (CMT) lab accredited to conform to AASHTO R 18 and other quality standards can benefit from adding ISO/IEC 17025 to their scope. First, a QMS framework developed based on the risk-based approach, as required by ISO/IEC 17025, adds an extra layer of robustness compared to a QMS developed based on other quality standards. Managing risks proactively will help in ensuring quality objectives are achieved effectively. Second, a QMS deployed based on ISO/IEC 17025 can lower operational costs and reduce business risks in the long-term by helping laboratories avoid making costly mistakes. Third, laboratories maintaining accreditation for ISO/IEC 17025 can set themselves apart from competitors.

Once the decision to pursue the ISO/IEC 17025 standard is made, the burden is on the lab to prepare for the assessment. An ISO/IEC 17025 assessment is usually combined with the review of the requirements of AASHTO R 18 and ASTM quality standards the lab chooses to include in its scope. This review is typically done after the regular AASHTO re:source technical assessment, where the lab technicians demonstrate various test methods selected by the lab, is completed. If you haven’t experienced an ISO/IEC 17025 assessment before, but you are curious about what to expect, this is how the big day might unfold.

Expect the day to start with the assessor opening the meeting to discuss the agenda for the day followed by Q&A, and then a walk-through of the facility.

5 Tips for Your Next   ISOIEC 17025 Assessment - tip 1
Tip #1:
 Assessors appreciate an organized lab. A CMT lab will not likely have museum-like cleanliness, but maintaining the lab in good working order can show that lab personnel care about and take pride in their work.

Expect the assessor to ask you for your QMS manual. The assessor will be reviewing the QMS manual to ensure its conformity with different sections of the ISO/IEC 17025 and all other quality standards the lab chooses to get accredited for.

5 Tips for Your Next   ISOIEC 17025 Assessment - tip 2
Tip #2:
The style and format of the QMS manual is the lab’s choice. There is no cookbook for this if all sections of the quality standards are addressed in the manual. But creating the QMS manual with section numbers that match with the section numbers in the ISO/IEC 17025 standard has distinct advantages: (1) The policies and procedures to meet the requirements of other quality standards can be included under one of the sections of the ISO/IEC 17025 standard, which makes the information common and streamlined, (2) As mentioned previously, the ISO/IEC 17025 standard encompasses a risk-based approach in developing the QMS. Because of this requirement, you will be automatically examining potential risks for every section in the manual and taking actions to mitigate them, (3) Because of (1) and (2), conducting an internal audit and deploying the QMS becomes easier for the lab manager, and (4) The assessor will have an easier time to go through the sections without having to look for information in assorted places in the manual.

Expect the assessor to ask you for documents such as equipment calibration records, corrective action reports for proficiency testing, internal audit documents, management review documents, customer feedback surveys, vendor evaluations, technician training records, complaints log, and so on. These documents will be verified to substantiate the commitments your lab has made in the QMS manual and to the various standards for which your lab is seeking accreditation.

5 Tips for Your Next   ISOIEC 17025 Assessment - tip 3
Tip #3:
ISO/IEC 17025 places significant importance on maintaining detailed documentation compared to all other quality standards. This is to ensure traceability of lab activities. The assessor will review the documents to ensure your lab practices the ‘do what you say and say what you do’ principle. So, maintaining a good and easily retrievable documentation system can save time for the lab and the assessor during assessment.

Expect the assessor to talk to all the lab staff about policies documented in the lab’s QMS manual.

5 Tips for Your Next   ISOIEC 17025 Assessment - tip 4
Tip #4:
Ensure all your lab personnel are aware of the contents of the most current QMS manual. Depending on the position responsibility of the lab personnel, the assessor will probe some of the lab practices and compare the responses to the promises made in your QMS manual. If your lab personnel aren’t sure about something, it is best to not speculate or postulate answers.

Expect the assessment process to take several hours. It typically takes more than one day.

5 Tips for Your Next   ISOIEC 17025 Assessment - tip 5
Tip #5:
Assessment process does not mean providing documentation to the assessor and leaving the room to attend a meeting or disappear for other reasons. The assessor will most likely have questions that need to be addressed. It is important that the lab manager or someone who has the authority to answer questions and has access to all the documents stay in the lab with the assessor for the entire assessment.


A Quality Management System serves as an important driving force toward achieving quality of products and services. Including the ISO/IEC 17025 standard to your scope of accreditation is a formal recognition of the lab’s technical and organizational competence. The decision to pursue the ISO/IEC 17025 quality standard should not be made lightly or without complete clarity, as there is a cost to the business. Conforming to this rigorous standard demonstrates the lab’s willingness to go above and beyond the customer’s minimum requirements to provide quality service. Whether it’s your first time or something your lab has been through in the past, preparing for an ISO/IEC 17025 assessment can be overwhelming and nerve-racking. This is because there are many pieces to the ISO/IEC 17025 puzzle, and the fear of something not working seamlessly in real-time is quite tangible. Following the five tips presented in this article and addressing them ahead of time can make the lab assessment seamless, straightforward, and a vindication of the lab’s good practices.

Editor’s note: We would like to thank Jayanth for being a guest author on this piece. If you are interested in writing something for us, please reach out AASHTO re:source Communications Manager, Kim Swanson.