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The question whether a given set of test items can be considered “identical” is often addressed in terms of the homogeneity of the test material from which said items were taken. However, for some types of matrices – in particular, for matrices consisting of minute separate particles, only some of which carry the analyte under consideration – even in the case of homogenous test material, an irreducible source of variability between test items may remain: the fundamental variability. In this paper, the concept of fundamental variability is explained, and procedures for reducing and characterizing it are described.

Measurement uncertainty is typically expressed in terms of a symmetric interval , where denotes the measurement result and the expanded uncertainty. However, in the case of heteroscedasticity, symmetric uncertainty intervals can be misleading. In this paper, a different approach for the calculation of uncertainty intervals is introduced. This approach is applicable when a validation study has been conducted with samples with known concentrations. It will be shown how, under certain circumstances, asymmetric uncertainty intervals arise quite naturally and lead to more reliable uncertainty intervals.

The ISO 2859 and ISO 3951 series provide acceptance sampling procedures for lot inspection, allowing both sample size and acceptance rule to be determined, starting from a specific value either for the consumer or producer risk. However, insufficient resources often make it difficult to implement “ISO sampling plans.” In cases where the sample size is determined by external constraints, the focus shifts from determining sample size to determining consumer and producer risks. Moreover, if the sample size is very low (e.g. one single item), prior information should be included in the statistical analysis. For this reason, it makes sense to work within a Bayesian theoretical framework, such as that described in JCGM 106. Accordingly, the approach from JCGM 106 is adopted and broadened so as to allow application to lot inspection. The discussion is based on a “real-life” example of lot inspection on the basis of a single item. Starting from simple assumptions, expressions for both the prior and posterior distributions are worked out, and it is shown how the concepts from JCGM 106 can be reinterpreted in the context of lot inspection. Conceptual differences regarding the definition of consumer and producer risks in JCGM 106 and in the ISO acceptance sampling standards are elucidated and a numerical example is provided.

Meat species authentication in food is most commonly based on the detection of genetic variations. Official food control laboratories frequently apply single and multiplex real-time polymerase chain reaction (PCR) assays and/or DNA arrays. However, in the near future, DNA metabarcoding, the generation of PCR products for DNA barcodes, followed by massively parallel sequencing by next generation sequencing (NGS) technologies, could be an attractive alternative. DNA metabarcoding is superior to well-established methodologies since it allows simultaneous identification of a wide variety of species not only in individual foodstuffs but even in complex mixtures. We have recently published a DNA metabarcoding assay for the identification and differentiation of 15 mammalian species and six poultry species. With the aim to harmonize analytical methods for food authentication across EU Member States, the DNA metabarcoding assay has been tested in an interlaboratory ring trial including 15 laboratories. Each laboratory analyzed 16 anonymously labelled samples (eight samples, two subsamples each), comprising six DNA extract mixtures, one DNA extract from a model sausage, and one DNA extract from maize (negative control). Evaluation of data on repeatability, reproducibility, robustness, and measurement uncertainty indicated that the DNA metabarcoding method is applicable for meat species authentication in routine analysis.

Supplemental material, sj-pdf-1-vdi-10.1177_10406387221115702 for Second round of an interlaboratory comparison of SARS-CoV2 molecular detection assays used by 45 veterinary diagnostic laboratories in the United States by Kaiping Deng, Steffen Uhlig, Laura B. Goodman, Hon S. Ip, Mary Lea Killian, Sarah M. Nemser, Jodie Ulaszek, Shannon Kiener, Matthew Kmet, Kirstin Frost, Karina Hettwer, Bertrand Colson, Kapil Nichani, Anja Schlierf, Andriy Tkachenko, Mothomang Mlalazi-Oyinloye, Andrew Scott, Ravinder Reddy and Gregory H. Tyson in Journal of Veterinary Diagnostic Investigation

Supplemental material, sj-pdf-1-vdi-10.1177_10406387221115702 for Second round of an interlaboratory comparison of SARS-CoV2 molecular detection assays used by 45 veterinary diagnostic laboratories in the United States by Kaiping Deng, Steffen Uhlig, Laura B. Goodman, Hon S. Ip, Mary Lea Killian, Sarah M. Nemser, Jodie Ulaszek, Shannon Kiener, Matthew Kmet, Kirstin Frost, Karina Hettwer, Bertrand Colson, Kapil Nichani, Anja Schlierf, Andriy Tkachenko, Mothomang Mlalazi-Oyinloye, Andrew Scott, Ravinder Reddy and Gregory H. Tyson in Journal of Veterinary Diagnostic Investigation

Supplemental material, sj-pdf-1-vdi-10.1177_10406387211029913 for Interlaboratory comparison of SARS-CoV2 molecular detection assays in use by U.S. veterinary diagnostic laboratories by Kaiping Deng, Steffen Uhlig, Hon S. Ip, Mary Lea Killian, Laura B. Goodman, Sarah Nemser, Jodie Ulaszek, Shannon Pickens, Robert Newkirk, Matthew Kmet, Kirstin Frost, Karina Hettwer, Bertrand Colson, Kapil Nichani, Anja Schlierf, Andriy Tkachenko, Ravinder Reddy and Renate Reimschuessel in Journal of Veterinary Diagnostic Investigation

Supplemental material, sj-pdf-1-vdi-10.1177_10406387211029913 for Interlaboratory comparison of SARS-CoV2 molecular detection assays in use by U.S. veterinary diagnostic laboratories by Kaiping Deng, Steffen Uhlig, Hon S. Ip, Mary Lea Killian, Laura B. Goodman, Sarah Nemser, Jodie Ulaszek, Shannon Pickens, Robert Newkirk, Matthew Kmet, Kirstin Frost, Karina Hettwer, Bertrand Colson, Kapil Nichani, Anja Schlierf, Andriy Tkachenko, Ravinder Reddy and Renate Reimschuessel in Journal of Veterinary Diagnostic Investigation

It is our pleasure to present the proceedings of the 13th International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions (ISHPMIE). The publication of these proceedings was heavily affected by the global situation. In light of these challenges, we are happy to compile proceedings consisting of 84 high-quality papers that reflect the scientific state-of-the-art in the following topical categories: Advances in explosion protection: Strategies, measures, and protective equipment; Detonations and DDT; Electro-chemical energy carriers; Explosion modelling and simulation; Explosion prevention; Explosion properties of substances and mixtures; Explosion testing; Explosions of sprays and vapors; Flame propagation and acceleration; Gas, dust, and hybrid mixture explosions; Hydrogen safety and Ignition phenomena. All articles in this volume have been subject to a peer review process administered by the proceeding editors.

Dies ist ein Beitrag für das 15. BAM-PTB-Kolloquium zur chemischen und physikalischen Sicherheitstechnik am 21. und 22. Mai 2019 bei der PTB in Braunschweig., Prävention beginnt im Prüflabor, wenn Chemikalien auf ihre gefährlichen Eigenschaften getestet werden. Dazu sind Prüfmethoden entwickelt und veröffentlicht worden, die heute weltweit Anwendung finden. Auf die Validität der Prüfmethode und richtige Durchführung der Prüfung im Laboratorium müssen sich Sicherheitsfachkräfte, Transporteure oder Händler verlassen können. Anhand der in den letzten 10 Jahren im Rahmen des CEQAT-DGHS von BAM und PTB durchgeführten Ringversuche (RV) wird gezeigt, dass bei allen bisher untersuchten Prüfmethoden ein Verbesserungsbedarf besteht. Die RV müssen daher zunächst auf die Methodenverbesserung und -validierung abzielen und nicht auf Leistungstests. Das Labormanagement und die praktische Durchführung der Prüfung sind in vielen Laboratorien verbesserungsbedürftig. Der Begriff „Erfahrung der Prüfer“ ist kritisch zu sehen: Eine „lange Erfahrung mit vielen Prüfungen“ ist nicht unbedingt ein Garant für richtige Ergebnisse. Bei der Prüfung der gefährlichen Eigenschaften von Chemikalien sind Referenzmaterialen auf Grund der Instabilität in der Regel nicht verfügbar. Für Prüflaboratorien sind RV daher eine Alternative bei der Qualitätssicherung. RV sind jedoch aufwendig und können nur in relativ großen Zeitabständen durchgeführt werden. Es sind deshalb Verfahren zur Verifizierung z. B. der in den Laboratorien verwendeten Prüfapparaturen zu entwickeln. Die Entwicklung von Verifizierungsverfahren wird am Bespiel der Prüfmethode UN Test N.5 demonstriert.

Dies ist ein Beitrag für das 15. BAM-PTB-Kolloquium zur chemischen und physikalischen Sicherheitstechnik am 21. und 22. Mai 2019 bei der PTB in Braunschweig., Die Ursachen für Chemikalienunfälle können vielfältig sein. Prävention beginnt bereits im Prüflabor, wenn Chemikalien auf ihre gefährlichen Eigenschaften getestet werden. Dazu sind Prüfmethoden entwickelt und veröffentlicht worden, die heute weltweit Anwendung finden. Auf die Validität der Prüfmethode und richtige Durchführung der Prüfung im Laboratorium müssen sich Sicherheitsfachkräfte, Transporteure oder Händler verlassen können. Anhand der in den letzten 10 Jahren im Rahmen des CEQAT-DGHS von BAM und PTB durchgeführten Ringversuche (RV) wird gezeigt, dass bei allen bisher untersuchten Prüfmethoden ein Verbesserungsbedarf besteht. Die RV müssen daher zunächst auf die Methodenverbesserung und -validierung abzielen und nicht auf Leistungstests. Das Labormanagement und die praktische Durchführung der Prüfung sind in vielen Laboratorien verbesserungsbedürftig. Der Begriff „Erfahrung der Prüfer“ ist kritisch zu sehen: Eine „lange Erfahrung mit vielen Prüfungen“ ist nicht unbedingt ein Garant für richtige Ergebnisse.

It is our pleasure to present the proceedings of the 13th International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions (ISHPMIE). The publication of these proceedings was heavily affected by the global situation. In light of these challenges, we are happy to compile proceedings consisting of 84 high-quality papers that reflect the scientific state-of-the-art in the following topical categories: Advances in explosion protection: Strategies, measures, and protective equipment; Detonations and DDT; Electro-chemical energy carriers; Explosion modelling and simulation; Explosion prevention; Explosion properties of substances and mixtures; Explosion testing; Explosions of sprays and vapors; Flame propagation and acceleration; Gas, dust, and hybrid mixture explosions; Hydrogen safety and Ignition phenomena. All articles in this volume have been subject to a peer review process administered by the proceeding editors.