Interlaboratory comparisons (ILCs) have been used for more than a century and many important concepts are linked to them. This leaflet addresses the basic terminology of ILCs, why some colloquial terms can be misleading or misunderstood, and the importance of harmonisation.&nbsp;An ‘ILC’ is the organisation, performance and evaluation of measurements or tests on the same or similar items by two or more laboratories in accordance with predetermined conditions [1]. ILCs have a variety of overall – and detailed – objectives, the three most common [2] being:<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Eurachem_Let_s_call_a_PT_scheme_a_PT_scheme_3_9993b9fb0f.jpg" alt="Eurachem: Let’s call a PT scheme a PT scheme" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Eurachem_Let_s_call_a_PT_scheme_a_PT_scheme_3_9993b9fb0f.jpg 245w," sizes="100vw" width="1516" height="472"><h4>Some comparisons have special names&nbsp;</h4>The evaluation of participant (laboratory, organisation or individual) performance is typically referred to as ‘proficiency testing’ (PT) or ‘external quality assessment’ [1]. When the main objective is evaluating the performance of, for example, a candidate standard method, the ILC is often called a ‘method performance study’ or a ‘collaborative study’ [2, 3]. The former is quite clear whereas wording such as “collaborative” and “cooperative” just stresses joint effort. A project aimed at producing a new certified reference material may involve several laboratories conducting analyses on agreed properties [4]. Not surprisingly, this work is sometimes labelled as a ‘material certification study’. Special ILCs used to demonstrate measurement capabilities of National Metrology Institutes are called ‘key comparisons’, ‘supplementary comparisons’, and ‘pilot studies’ [5].&nbsp;<h4>Some terms can be confusing&nbsp;</h4>Other terms for ILCs, including ‘ring test’, ‘round robin’ and ‘circle analysis’, are common in the literature. They have, however, been used for different objectives and different designs and may be ambiguous or understood differently by laboratory staff. The use of these terms may, for example, imply a specific way of distributing the ILC sample. ISO/IEC 17043 uses ‘sequential scheme’, for a PT where a unique item is transferred between the participants and ‘simultaneous scheme’, in which similar items from a batch are distributed simultaneously to the participants [1].&nbsp;Terms like ‘measurement audit’, ‘interlaboratory testing scheme’, ‘measurement comparison scheme’, ‘rapid performance evaluation scheme’ and ‘intercalibration’ may not correctly reflect the category of laboratory involved, or the type of work participants do during the ILC.&nbsp;When in 1994 the IUPAC defined and described three major types of ‘interlaboratory studies’, the word ‘study’ was preferred to synonyms such as ‘trial’, ‘exercise’, ‘test’, ‘evaluation’ or ‘check’ [2].<h4>Let’s try to harmonise&nbsp;</h4>Many laboratory staff are unaware of official terms related to ILCs but recognise the acronym PT and words like ‘ring test’. Ideally, we would use a common scientific language, but harmonisation is time consuming. Terms appear and disappear and definitions change. The same term can be defined differently, even in different international standards. Lack of standards and guidelines in local languages can cause confusion and contribute to spreading of less appropriate terms.&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Eurachem_Let_s_call_a_PT_scheme_a_PT_scheme_2_820043ce8b.jpg" alt="Eurachem: Let’s call a PT scheme a PT scheme" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Eurachem_Let_s_call_a_PT_scheme_a_PT_scheme_2_820043ce8b.jpg 234w," sizes="100vw" width="1006" height="671">Much confusion can be avoided by clear reference to relevant standards and sectoral guides. ISO/ IEC 17043 [1] and ISO 13528 [6] contain many important concepts related to PT schemes and other ILCs. Some of these are also incorporated into ISO/IEC 17025 [7]. Additional useful, and free, tools are the Eurachem PT Guide [8] and the ISO online browsing platform [9].&nbsp;In writing guidance and instructions, remember that the term ‘interlaboratory comparison’ has a broad meaning and can be used for all cases described above. Sometimes this is clear enough for the reader. In other cases, use acknowledged terms that reflect the detailed objective of the ILC. Let’s call a PT scheme a PT scheme!

Let’s call a PT scheme a PT scheme!

The countdown is on for one of the world’s leading conferences dedicated to food analysis. The 12th International Symposium on Recent Advances in Food Analysis (RAFA 2026), taking place in Prague from 3–6 November 2026, is approaching two important milestones: the Early Bird registration deadline and the deadline for oral abstract submissions, both ending on 30 June 2026. Researchers, analysts, industry professionals, regulators, and students are encouraged to secure their participation at a reduced registration rate and take advantage of the opportunity to present their latest scientific results to the international food analysis community.RAFA 2026 will once again bring together leading experts from academia, industry, and regulatory organizations to discuss the latest developments in food safety, authenticity, contaminants, non-target screening, PFAS, microplastics, food contact materials, artificial intelligence, and advanced analytical technologies. The preliminary program already features an outstanding lineup of internationally recognized speakers addressing some of the most pressing challenges in modern food analysis and food safety.<h3>Registration</h3><blockquote>👉<a target="_blank" rel="noopener noreferrer" href="https://rafa.easyevent.eu/tickets/">Register to attend RAFA 2026!</a>Early-bird registration until 30 June, 2026</blockquote>After successful submission of your registration, you will receive by e-mail (i) an automatic confirmation of receipt indicating the total amount of payment due (either for bank transfer or for on-line payment by card), (ii) login to Member section where you can administrate your profile, submit your abstracts, and from September 2026 register for satellite events, workshops and seminars. If it will not be delivered within a few minutes after submission of your registration please contact us at RAFA2026@vscht.cz.As soon as payment of registration fee is processed, you will also receive by e-mail (iii) confirmation of payment.<h4>Registration Fees</h4><ul><li>Smart rate (Until 30 June, 2026): € 655</li><li>Regular registration (Until 30 September, 2026): € 855</li><li>Late registration (From 1 October, 2026): € 955</li><li>Student rate*&nbsp;<ul><li>Until 30 June, 2026: € 465</li><li>From 1 July, 2026: € 605</li></ul></li></ul>* The proof of student status (e.g. copy of a student identify card) is requested as an attachment of the registration form.<h5>The regular registration fee will include:</h5><ul><li>Attendance at all scientific sessions, workshops, seminars, vendor seminars and other satellite events</li><li>Access to the poster and exhibition area</li><li>Conference kit (name badge, conference bag, conference documents, certificate of participation, certificate of presentation on request)</li><li>Final programme</li><li>E-Book of Abstracts</li><li>Coffee breaks</li><li>Buffet luncheons</li><li>Welcome drink</li></ul>In the registration form you can register free of charge for the welcome drink and you can also order ticket(s) for the conference dinner (€ 85).Please note that your registration is firm when your payment has been received.<h3>Abstract submission</h3><blockquote>👉<a target="_blank" rel="noopener noreferrer" href="https://rafa.easyevent.eu/tickets/">Submit your ABSTRACT HERE!</a>In order to submit an abstract, you must first register to attend RAFA 2026. After registration you will receive an access to the Member section where you can submit your abstract(s).</blockquote>&nbsp;After successful submission of your abstract you will receive an automatic confirmation of receipt of submitted abstract via e-mail. If it will not be delivered within a few minutes after submission of your abstract please check at first your spam box-mail and then contact us at RAFA2026@vscht.cz.Please ensure that your abstract does not contain spelling, grammatical or scientific errors. Even though modifications of your submitted abstract will be allowed in the Abstract section of the Member section until the deadline for the abstract submission, please be confident on the lack of errors in your final version prior to starting the submission process.The abstract will be reproduced exactly as submitted. No proofreading will be done, although some corrections may be requested by the reviewers.If you need to withdraw your abstract, a written statement reflecting the reasons for this decision must be sent to RAFA2026@vscht.cz no later than September 30, 2026.<h4>Important notice:</h4><blockquote>1 registered participant can submit no more than 2 abstracts.</blockquote>To apply for a young scientist’s oral presentation, as an indication please respect the rule that you should be born in 1991 or later.The text of the abstract should be limited to 3000 characters including spaces. Tables and pictures are not allowed.Abstracts of oral presentations and posters will be included into the "e-Book of Abstracts" only after receipt of the conference registration fee. Any payment of the registration fee has to be received until September 30, 2026, otherwise contribution(s) will not be included into the e-Book of Abstracts and the Conference programme.<h3>Program</h3><h4>Invited Speakers</h4><h5>Food allergen risk assessment: Past, present, future</h5><ul><li>Ben Remington from Remington Consulting Group B.V., Utrecht, the Netherlands &amp; University of Nebraska, USA</li></ul>Food allergy and allergen management are global public health issues, and consumer protection depends on transparent and trustworthy labelling. While 30 years of scientific advances show that low level exposures, or reference doses, are unlikely to trigger reactions in most allergic individuals, harmonized and globally aligned regulations are still needed to promote consistent allergen risk assessment and labelling decisions. This presentation will discuss the landscape of allergen risk assessment, global policy developments, current research and future needs in the area.<h5>Unmasking hidden adulteration in honey: Strategies for detecting and characterizing honeys produced from sugar-fed colonies</h5><ul><li>Oscar Nuñez Burcio from University of Barcelona, Barcelona, Spain</li></ul>From hive to jar, not all honey tells the same story. This presentation addresses hidden adulteration associated with sugar-fed bee colonies, highlighting implications for authenticity, production practices, and the need for a more precise characterization of honey to ensure consumer trust.<h5>Analytical and toxicological methods for safety of food contact materials</h5><ul><li>Erich Leitner from Graz University of Technology, Institute of Analytical Chemistry and Food Chemistry, Graz, Austria</li></ul>Food packaging plays a critical role in protecting and preserving food throughout the supply chain. All packaging materials intended to come into contact with food must comply with strict EU safety rules. Due to increased complexity of packaging solutions, lowering legal limits and increasing numbers of target compounds, we also have to adapt the strategies used to verify and guarantee the safety of these materials.<h5>Data-driven strategies to reduce complexity in non-target HRMS analysis of food samples</h5><ul><li>Anneli Kruve from Stockholm University, Stockholm, Sweden</li></ul>LC/HRMS based non-target screening can detect hundreds to thousands of chemical features in complex food and environmental samples. Investigating all of these in detail is practically impossible, so which ones to focus on? Novel computational tools developed in computational mass spectrometry allow predicting the toxicity and concentration of the detected chemical features even if these have not yet been fully structurally elucidated. Combining these predictions enables us to focus on the chemical features possessing high risk.<h5>Role of AI in the identification of emerging food systems risks</h5><ul><li>Ákos Bernard Jóźwiak from Syreon Research Institute, Budapest, Hungary</li></ul>AI-assisted evidence synthesis – spanning curated scientific evidence, exposome data, and network analysis – is the backbone of next-generation emerging chemical food safety risk identification, enabling earlier signals and more resilient surveillance systems.<h5>Challenges of microplastics analysis in the context of food safety</h5><ul><li>Dorte Herzke from Norwegian Institute of Public Health, Oslo, Norway</li></ul>Food and food packaging are major sources of micro- and nanoplastic exposure. Plastics used in processing, storage, and packaging can release particles through heat, abrasion, and degradation. Small particles below 2 µm may cross gut barriers and carry chemicals, highlighting the need for robust and sensitive measurement methods.<h5>Never-ending analytical challenges in PFAS analysis of food</h5><ul><li>Darina Dvořáková from University of Chemistry and Technology Prague, Prague, Czechia</li></ul>Exploring and monitoring PFAS in food requires advanced strategies. Combining targeted, suspect, and non-target HRMS analysis, determination of total fluorine and sum parameters, and novel sensors provides new insights into PFAS occurrence and supports food safety monitoring.<h5>An overview of the latest scientific knowledge on process contaminants in food for appropriate risk management measures</h5><ul><li>Thierry Delatour from Nestlé Research, Lausanne, Switzerland.</li></ul>Recent scientific findings related to acrylamide and furans formation, occurrence and analytical methods in food provide important insights for risk management.

Deadline for RAFA 2026 Early Registration and Oral Abstract Submission is approaching

Our Library never stops expanding. What are the most recent contributions to LabRulezICPMS Library in the week of 22nd June 2026? Check out new documents from the field of spectroscopy/spectrometry and related techniques!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT SPECTROSCOPY/SPECTROMETRY RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">LabRulezGCMS</a> libraries.</blockquote>This week we bring you technical note by Agilent Technologies, application note by Shimadzu and other document by Thermo Fisher Scientific!<h3>1. Agilent Technologies: Dual-Cell System (DCS) and Advanced Helium Mode (AHM)</h3>Technological developments for higher sensitivity and better interference removal than traditional He-KED<ul><li>Technical note</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/labrulez-bucket-strapi-h3hsga3/te_batch_conversion_tool_9500_icp_ms_5994_9214en_agilent_0a1bba76e2.pdf">Full PDF for download</a></li></ul><h4>Evolution of Agilent’s Collision Reaction Cell (CRC) technology&nbsp;</h4><ul><li>2001: Launched the first ICP-MS with CRC—the Agilent 7500c with Octopole Reaction System (ORS)&nbsp;</li><li>2011: Introduced High Energy Helium Mode (HEHe) using Collision Induced Dissociation (CID)&nbsp;</li><li>2012: Released the world’s first Triple Quadrupole ICP-MS—the Agilent 8800 ICP-QQQ&nbsp;</li><li>2016: Launched the second generation Triple Quadrupole ICP-MS with Axial Acceleration—the Agilent 8900 ICP-QQQ&nbsp;</li><li>2026: Introduced the innovative Dual-Cell System (DCS) and Advanced Helium Mode (AHM) for the Agilent 9500 ICP-QQQ</li></ul>Collision/Reaction Cell (CRC) technology is now a standard feature in modern ICP-MS systems, providing a reliable means of eliminating spectral interferences that compromise data quality. ICP-MS systems with integrated CRCs range from single quadrupole (SQ) ICP-MS used in environmental and food analysis, to triple quadrupole ICP-MS (ICP-QQQ) for advanced research applications. For routine applications, Helium Kinetic Energy Discrimination (He KED) mode, commonly referred to as helium mode (He mode), is the most widely used CRC operational mode. The widespread use of He mode is due to its universal effectiveness in reducing a broad range of polyatomic interferences without the need for element-specific optimization.&nbsp;Unlike CRCs that rely on reactive cell gases and require complex tuning (often referred to as reaction cells), He mode effectively mitigates many commonly occurring polyatomic ion interferences without the need for intricate adjustments. In contrast, reaction cells often require careful selection of gas type (such as ammonia or oxygen) and tuning parameters based on the specific interfering ions on analytes of interest.&nbsp;Building on the simplicity of He mode, Agilent has developed Advanced Helium Mode (AHM) for the <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library?mainauthorItems=10&amp;search=9500">Agilent 9500 Triple Quadrupole ICP-MS (ICP-QQQ)</a>. AHM represents a breakthrough in interference removal technology, enabled by the newly designed Agilent Dual-Cell System (DCS) and high-speed cell voltage control. These innovations deliver high sensitivity across the mass range and superior interference removal performance for routine applications. Compared to conventional He mode, AHM demonstrates the following improvements:<ul><li>Around a 20-fold sensitivity improvement for low-mass elements, such as beryllium (Be) and boron (B)&nbsp;</li><li>Around a 2-fold improvement for mid-to-high mass elements&nbsp;</li><li>A reduction of more than 33% in data acquisition time while maintaining detection limits (DLs), accelerating analytical measurement times&nbsp;</li></ul>AHM not only replaces traditional He KED but also consolidates multiple tuning modes including no gas, He, and HEHe into a single, streamlined mode. Integrated into the 9500 ICP-QQQ, AHM is a next-generation standard He mode that is faster, simpler, and delivers higher performance than its predecessor. This technical note describes the performance enhancement mechanisms of the DCS and AHM. It also includes some comparative results with conventional He KED mode to highlight the analytical improvements of AHM.<h4>Overview and advantages of AHM&nbsp;</h4>Typically, multi-element ICP-MS methods apply no gas mode to the determination of low-mass elements like Be and B due to low sensitivity in traditional He KED mode. Consequently, many routine ICP-MS applications have required multiple tune setups, combining no gas, He, and HEHe. Each mode switch introduces a delay due to cell pressure stabilization requirements.&nbsp;In practice, low-mass elements (m/z &lt; 23) are generally unaffected by polyatomic ion interferences, so KED is often unnecessary. Therefore, in AHM, different voltages are applied to the DCS (effectively disabling KED) for low-mass elements, while keeping standard settings for elements with m/z ≥ 23.&nbsp;The DCS voltages are dynamically switched in sync with Q2 using a high-speed voltage control circuit, providing over 20× sensitivity improvement for low-mass elements compared to conventional He mode. AHM eliminates the need to run in no gas mode, greatly simplifying the method. As a default approach, AHM alone is suitable for most applications.1<h3>2. Shimadzu: Damping Force Characteristic Test of Suspension Struts [JASO C611]</h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_01017_en_2fbbb9c247.pdf">Full PDF for download</a></li></ul><h5>User Benefits</h5><ul><li>Damping force characteristic tests on suspension struts can be performed based on the JASO C611 standard.&nbsp;</li><li>Combination test enables automatic speed change and measurement.&nbsp;</li><li>High responsiveness of the EMT series enables testing at high excitation speed.</li></ul>Various components play an important role in achieving a comfortable ride in vehicles. Among them, the suspension strut used in the suspension system is an important component that stabilizes the vehicle body by mitigating the impact caused by uneven road surfaces.&nbsp;“JASO C611 Suspension Struts for Automobiles”1), a standard of JASO (Japanese Automotive Standards Organization), established by JSAE, specifies the definition, quality, and test method for suspension struts. There is no international standard that is equivalent to JASO C611.&nbsp;In order to improve the performance of suspension struts, it is necessary to measure the damping force against speed by changing the excitation speed. The performance of suspension struts can be confirmed by measuring the response, such as the relationship between speed and damping force and the Lissajous waveform.&nbsp;This article introduces an example of the test method “Damping Force Characteristic Test” specified in JASO C611, which was conducted on a Shimadzu EMT series electromagnetic fatigue testing machine.<h4>Testing Equipment&nbsp;</h4>The EMT-1kNV-50 electromagnetic dynamic and fatigue testing machine was used in this test. Fig. 1 shows a photograph of the testing machine. The electromagnetic actuator with extremely high frequency response enables highly accurate dynamic testing. In this test, the maximum test speed was 0.6 m/s. The EMT seriesis most suitable for testing at such high frequencies.<h4>Conclusion&nbsp;</h4>A damping force characteristic test on a suspension strut based on JASO C611 was conducted using an EMT series electromagnetic fatigue testing machine and Windows software for 4830. The test conditions were set using the excitation speed, and it was confirmed that the test was accurately controlled as set. The standard “JASO C611 Suspension Struts for Automobiles” referred to this time is derived from “JASO C602 Automotive Parts - Telescopic Shock Absorbers for Suspension Systems”2). Although C602 also prescribes a damping force characteristic test, it is almost equivalent to the C611, and the test machine configuration can be used by replacing the jig.<h3>3. Thermo Fisher Scientific: <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2206">Hypulse Surface Analysis System</a></h3><ul><li>Other document</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Hypulse_DS_0516_EN_05_2025_1998238_WEB_0e44628a5e.pdf">Full PDF for download</a></li></ul><h4>Key features&nbsp;</h4><ul><li>Unique depth profiling capability. The femtosecond laser ablation system provides controlled material removal without inducing chemical damage to your sample.&nbsp;</li><li>Fast, efficient XPS. Quick sample pump-down times, a unique sample viewing system, and high sensitivity for all analysis areas help ensure exceptional data quality, even for highly challenging samples.&nbsp;</li><li>Co-incident additional spectroscopy. Optimize the information obtained from features of interest with the addition of optional analytical techniques, including ion scattering spectroscopy, reflected electron energy loss spectroscopy, and UV photoelectron spectroscopy.&nbsp;</li><li>Fully featured software. The latest version of the Avantage Data System is included for data collection and analysis, with the ability to import data into Thermo Scientific Maps Software for correlation with electron microscopy images.</li></ul><h4>Technical highlights&nbsp;</h4><h5>Micro-focused, monochromated aluminum K-alpha X-ray source&nbsp;</h5><ul><li>Computer-controlled quartz-crystal monochromator&nbsp;</li><li>Software-adjustable spot size&nbsp;</li><li>Spot size range: 10–400 μm&nbsp;</li><li>Motorized, water-cooled anode with 16 positions&nbsp;</li></ul><h5>Electron optics and analyzer</h5><ul><li>Electrostatic objective lens&nbsp;</li><li>Full 180° hemispherical μ-metal shielded analyzer&nbsp;</li><li>Continuously selectable pass energy: 1–400 eV&nbsp;</li><li>128-channel, signature-corrected, positionsensitive detector&nbsp;</li><li>Automatic energy scale and transmission function calibration&nbsp;</li></ul><h5>Charge compensation system&nbsp;</h5><ul><li>Patented dual-beam electron and ion source&nbsp;</li><li>Beam energy for charge compensation: 0–5 eV&nbsp;</li></ul><h5>Femtosecond-laser ablation system&nbsp;</h5><ul><li>Fully integrated 1,030 nm pulsed femtosecond-laser source&nbsp;</li><li>Class 1 laser system&nbsp;</li><li>Tunable pulse energy up to 1 mJ&nbsp;</li><li>Computer-controlled attenuation optimizes ablation conditions&nbsp;</li><li>Beam imaging module for system calibration and alignment</li></ul>

News from LabRulezICPMS Library - Week 26, 2026

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RAFA provides an overview of contemporary trends in ANALYTICAL & BIOANALYTICAL STRATEGIES IN FOOD QUALITY AND SAFETY CONTROL and discusses CHALLENGES / NOVEL APPROACHES IN FOOD AND NATURAL PRODUCTS ANALYSIS.

Recent Advances in Food Analysis (RAFA)

Eurachem is a European network promoting international traceability of chemical measurements and good analytical practice. It provides expert guidance, supports method validation, uncertainty evaluation, proficiency testing, and facilitates discussion on technical and policy issues in analytical quality.

Eurachem

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News from LabRulezICPMS Library - Week 26, 2026

Deadline for RAFA 2026 Early Registration and Oral Abstract Submission is approaching

Let’s call a PT scheme a PT scheme!