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For the classification and safe handling and use of the chemicals, special standardized testing proce-dures have been developed and are used world-wide. Safety experts must be able to fully rely on the precise execution of the respective laboratory tests and assessments. In this context interlaboratory tests (round robin tests, interlaboratory comparisons / intercomparisons) are a crucial element of a laboratory's quality system. Participation in interlaboratory tests is explicitly recommended by the standard ISO/IEC 17025. The present document reports on the results of the interlaboratory test 2010/2011 on the test method DIN EN 15188:2007 “Determination of the spontaneous ignition behaviour of dust accumulations” [1] which was organized by the Center for Quality Assurance for Testing of Dangerous Goods and Haz-ardous Substances. The test method DIN EN 15188:2007 is applied to characterize the self-ignition behaviour of combus-tible dusts. The experimental basis for describing the self-ignition behaviour of a given dust is the de-termination of the self-ignition temperatures (TSI) of differently-sized volumes of the dust sample by isoperibolic hot storage experiments (storage at constant oven temperatures) in commercially availa-ble ovens. The results thus measured reflect the dependence of self-ignition temperatures upon dust volume [1]. Several internal investigations and interlaboratory comparisons in the past have shown significant differences between the lab-specific results of hot storage tests. Figure 2-1 shows the Pseudo-Arrhenius plot of hot storage tests of eight different laboratories (Round Robin Test 2002, BAM). The dust under this investigation was Lycopodium powder (spores). The par-ticipants of this interlaboratory test used different laboratory ovens (size, ventilation) as well as differ-ent sample baskets (shape, mesh size, single- and double-walled). Figure 2-1 shows clearly that this test failed to produce reasonable reproducibility of the TSI between the different laboratories. As possible reasons for the deviations have been identified lab-specific dif-ferences, e.g.: - oven ventilation (enforced, natural convection), - oven size, - sample baskets, - radiation effects, - measuring precision (temperature difference between tests with ignition and no ignition), - minimum sample size. To reduce the differences between the labs it was necessary to ameliorate the testing method and to improve the execution of the method by the lab. From there, the installation of an inner chamber into the laboratory oven was suggested as experimental set-up in EN 15188:2007 to provide more repro-ducible test conditions. The aappropriateness of this set-up has not been verified yet. The current interlaboratory test 2010-2011 focuses on the use of a special mesh wire screen and spe-cial volumes of the sample baskets (cubes) to normalise/harmonise the test conditions in the different labs. In preparation for the interlaboratory test a joint program between Syngenta and BAM has been initiated in 2009. As a result of these investigations a modified set-up ( chapter 3) has been identi-fied to be probably more appropriate than the suggested set-up in DIN EN-15188:2007. Due to the time-consuming test procedure and to optimize the workflow for the laboratories this in-terlaboratory test should be performed stepwise as a multi-level test ( chapter 5.4) on one typical test sample.

The classification of solid oxidizers according to the GHS (Globally Harmonized System of Classifica-tion and Labelling of Chemicals) and according to regulations on the transport of dangerous goods (based on the UN Recommendations/Model Regulations and implemented in all carrier domains as transport by road, railway, sea, air) is performed on the basis of the results of the UN test O.1 (―Test for oxidizing solids‖ described in chapter 34.4.1 in the Recommendations on the Transport of Danger-ous Goods, Manual of Tests and Criteria, Fifth revised edition, United Nations, New York and Geneva, 2009). This test was introduced into the UN Test Manual in 1995 as a replacement for a similar test from 1986. Even though the O.1 test is much better than the previous one there are still many prob-lems with this test. For this reason the IGUS-EOS working group (international group of experts on the explosion risks of unstable substances – working group: energetic and oxidizing substances) installed an ad-hoc working group in 2002 assigned with the task of proposing solutions for the existing prob-lems. The adequacy of such proposals has to be proven preferably by interlaboratory comparison (interlaboratory test) before they are presented to the UN Sub Committee for adoption into the UN Test Manual. The present report is the evaluation of an interlaboratory test which was designed by the Ad-hoc working group in order to find out whether the current method of comparing combustion times of test mixtures with those of reference mixtures is suitable in principle and whether some approaches for improvement of the method can be identified.

Metaproteomics has matured into a powerful tool to assess functional interactions in microbial communities. While many metaproteomic workflows are available, the impact of method choice on results remains unclear. Here, we carry out a community-driven, multi-laboratory comparison in metaproteomics: the critical assessment of metaproteome investigation study (CAMPI). Based on well-established workflows, we evaluate the effect of sample preparation, mass spectrometry, and bioinformatic analysis using two samples: a simplified, laboratory-assembled human intestinal model and a human fecal sample. We observe that variability at the peptide level is predominantly due to sample processing workflows, with a smaller contribution of bioinformatic pipelines. These peptide-level differences largely disappear at the protein group level. While differences are observed for predicted community composition, similar functional profiles are obtained across workflows. CAMPI demonstrates the robustness of present-day metaproteomics research, serves as a template for multi-laboratory studies in metaproteomics, and provides publicly available data sets for benchmarking future developments.

For the classification of chemicals, special standardized test procedures have been developed and are used world-wide. Safe handling and use of these chemicals depend on the correct classification which therefore must be based on the precise and correct execution of the tests and their evaluation. In this context interlaboratory tests (round robin tests, interlaboratory comparisons / intercomparisons) are a crucial element of a laboratory's quality system. Participation in interlaboratory tests is explicitly recommended by the standard ISO/IEC 17025. The present document reports on the results of the interlaboratory test 2007 on the method UN Test N.5 “Test method for substances which in contact with water emit flammable gases” [1] / EC A.12 “Flammability (contact with water)” [2] which was organized by the Center for Quality Assurance for Testing of Dangerous Goods and Hazardous Substances. In dependence on the chemical structure and/or the physical form and state (e.g. particle size) substances or mixtures may be able to react with water (even water damp / air humidity) under normal ambient temperature conditions. Sometimes this reaction can be violent and/or with significant generation of heat. Especially if gases are evolved this reaction may become dangerous. In addition, it is important to know whether a substance emits flammable gases due to contact with water because special precautions are necessary especially with regard to explosion protection. The methods UN Test N.5 and EC A.12 are applied to characterize chemical substances or mixtures which in contact with water emit flammable gases. To differentiate between chemicals with these properties and chemicals which are not classified as hazardous / dangerous, the substance’s gas evolution rate is determined and compared to the classification criteria(s) in the last step of the test method. In the methods UN Test N.5 / EC A.12 no special laboratory apparatus / measuring technique to determine gas evolving flow is required. However, practical experience shows that the testing procedure for substances and mixtures which in contact with water emit flammable gases is sensitive to a number of influencing factors. Since the methods (UN N.5 / EC A.12) were developed and came into force in the early nineties a systematic review concerning the practical application of the test method has not been carried out.