NF EN Research Articles

The development of a standard qualification protocol for all climatic and thermostatic chambers according to the requirements of the Good Manufacturing Practices (GMP) and the standards of characterization: NF X 15-140 and NF EN 60068-3.

The qualification of climatic and thermostatic chambers is not based on a single standard, but it also requires the control of several standards such as NF X 15-140, NF EN 60068-3 and the requirements of the Good Manufacturing Practices (GMP). So, currently the qualifiers only take into account the standard NF X 15-140 or NF EN 60068-3 to make their qualification, without giving importance to other criteria that must be treated or accurately tested and that are not mentioned in these standards, but they are cited in other references such as GMP (Good Manufacturing Practices). Because with the standards NF X 15-140 or NF EN 60068-3 we can only judge on the conformity of the distribution of temperature and humidity into the chamber. That is to say, in qualification terms, it is the last step of the qualification, which is the PQ (Performance Qualification). While in the GMP, we find the other steps of qualification, which are the IQ (Installation Qualification) and the OQ (Operational Qualification) and even in the GMP, they are not well detailed. Thanks to the use of the characterization standards such as NF X 15-140 and NF EN 60068-3 and the requirements of the Good Manufacturing Practices, we have been able to develop a standard qualification protocol. Indeed, this protocol could be used for all climatic and thermostatic chambers for the purpose of their qualification. Also, it could allow us to make a judgment on the conformity or not of the chamber to qualify

Statistical analysis of the effluent quality of 231 on-site sanitation facilities in France monitored during a 6-year period.

On-site wastewater treatment systems are approved by the French regulation based on the results of platform tests following the European standard NF EN 12566-3. In addition to this approval for the treatment system, at least 90% of outlet concentrations have to be below 30 mg L-1 for total suspended solids (TSS) and 35 mg L-1 for biochemical oxygen demand. The aim of this study is to evaluate the effluent quality of these treatment systems on site, i.e. under real operating conditions, and to assess their performances. Between 2011 and 2016, 1,286 treated wastewater samples were taken from 231 on-site sanitation facilities in France. Data collected are heterogeneous and a robust statistical methodology (using a generalized log-linear model) was used to study the effects of four explanatory variables (treatment systems, loading rate, aging and sampling methods) on the distribution of treated wastewater concentrations. The model calculates median outlet concentrations depending on the effects identified. Its application allowed studying and comparing the outlet median concentrations of 21 on-site sanitation systems classified into nine categories and three groups. Four treatment systems out of the 21 monitored showed TSS median outlet concentrations below 10 mg L-1 and four treatment systems have TSS medians higher than the regulatory threshold of 30 mg L-1.

L’incertitude en sérologie infectieuse

Uncertainty in serological testingTaking into account and estimation of uncertainty are now mandatory to meet the guidelines for accreditation of medicine laboratories according to NF EN ISO 15 189 norm. Serological tests in infectious diseases are frequently considered as quantitative assays and evaluating the analytical uncertainty is clear to us. The most pertinent level for assessing uncertainty is the positive threshold that permits to discriminate the presence or absence of the antibody or the antigen of interest. Total uncertainty is determined using bias and reproducibility of the method. A low level of the internal quality control is optimal to determine reproducibility while bias will be obtained using, if available, WHO standards for methods with results in international units. Global uncertainty is then a good way to optimize the gray zone according to the real performances of the methods. In addition to analytical uncertainty, diagnosis specificity and lower limit of detection also impact significantly the predictive value of the results and thus must not be neglected. Considering the rarity of international standards for most of the serological markers, the choice of external quality assessment programs is particularly critical.

Accreditation of the screening for the rectal carriage of vanA and/or vanB Vancomycin-resistant enterococci by an accredited laboratory under the standard NF EN ISO/IEC 17025:2005

The quality of the screening of vanA and/or vanB Vancomycin-resistant enterococcal (VRE) carriage by patients transferred from foreign countries plays a role in the management of risks linked to extensively drug resistant organisms (XDRO). Accreditation of the screening according to the NF EN ISO 15189 and NF EN ISO/IEC 17025 standards contributes to satisfy the level of quality. Our laboratory was already accredited according to the NF EN ISO/IEC 17025 standard. We used its quality management system and the type B widened flexible scope to identify the required criteria based on microbiology and infection control standards and those of Afnor and Cofrac, and to validate the screening procedure. Accreditation was obtained for use of the Type B scope, for culture-based detection and identification (codes BA1 and BA5), for determination of the minimal inhibitory concentrations of glycopeptides (code BA6), and for the detection of resistance genes to glycopeptides by polymerase chain reaction (code BA8). The maturity of our quality management system contributed to validate the screening procedures following the required criteria of the NF EN ISO/IEC 17025 standard.

Characterization of the Venturi flowmeters for the control of ITER magnets

Within the framework of the ITER project, CEA/SBT is in charge of the design, manufacturing and delivery of 277 Venturi flowmeters. The latter were developed for either the control of the supercritical helium flow in the magnets at cryogenic temperature (4.5 K) or the operation of the current leads at room temperature. Depending on the temperature, the values of the Reynolds number in the Venturi tubes are significantly higher or lower than those specified in the standard NF EN ISO 5167-4 regarding the design of Venturi flowmeters. An experimental determination of the flowmeter coefficient was therefore required. Due to the large number of flowmeters, a manufacturing strategy was developed in order to obtain a reproducible behaviour. This strategy was validated by the experimental results obtained at room and cryogenic temperature.

Accreditation of the toxicological screening: recommendations of the SFBC-SFTA group

Toxicological screening is a specific approach to analytical toxicology that uses analytical tools such as GC-MS, LC-UV (diode array) or LC-MS. Toxicological screening allows the detection and simultaneous identification of a large number of compounds. The results may be based on the use of one or more techniques. As part of the accreditation process for medical biology examinations according to standard NF EN ISO 15189, the group from SFTA and SFBC recommends an approach to accredit toxicological screening. Indeed, the complexity of the accreditation of this analysis comes in particular from the high number of compounds that can be detected. Validation parameters are discussed in the specific context of toxicological screening by considering two distinct approaches: the simple identification of compounds, or the identification and estimation of a range of concentration related to clinical outcomes.

Chlorhexidine Digluconate Formulations Used for Skin Antisepsis

Aims: The representativeness of European standards phase 2, step 1 regarding bactericidal and yeasticidal activities was used for the comparison of two marketed antiseptic solutions, one containing chlorhexidine digluconate (0.5%) and the other combining chlorhexidine digluconate (0.25%), benzalkonium chloride (0.025%) and benzylic alcohol (4%). Methods: The bactericidal activity of the antiseptic solutions used pure or diluted was assessed according to the European standards NF EN 13727 and NF EN 13624 for the bactericidal and yeasticidal activity respectively. The contact time was 1 min at 20°C. Interfering substances used correspond to soiling conditions i.e. bovine serum albumin and sheep erythrocytes. A reduction of colony-forming units by ≥5 log10 was deemed to meet the requirements to conclude bactericidal activity and ≥4 log10 for yeasticidal activity. Results: Regarding all the mandatory strains, both solutions are bactericidal and yeasticidal even after a 40% dilution and even under “dirty” conditions. Conclusions: The present study demonstrated the efficient bactericidal and yeasticidal activity of aqueous solutions containing chlorhexidine digluconate either alone at a concentration of 0.5% (w/v) or at a concentration of 0.25% (w/v) when combined with benzalkonium chloride at 0.025% (w/v) and benzylic alcohol 4%. These results have to be considered regarding the respective formulations and potent allergy risks.

Caractéristiques des élevages avicoles et évaluation de leur niveau de contamination par Salmonella spp. et Escherichia coli dans les villes de N’Djaména et Doba au Tchad

The main purpose of this study is to evaluate the characteristics of poultry farm sand the level of contamination of chickens farmed in the towns of N'Djamena and Doba by Salmonella spp. and Escherichia coli. Information, based on both formal and informal surveys, was collected from ten broiler chicken farms in N'Djamena and 16 traditional farms in Doba, mainly small establishments with low levels of investment. A total of 1,090 samples were taken from these farms over three periods, each of three months, from June to August 2014 then from March to May 2015 for Doba, and from November 2014 to January 2015 for N'Djamena. The NF EN ISO 6579 method and the seeding of a specific eosin methylene blue (EMB) agar were used to isolate 105 bacteria strains, including 65 (5.96%) strains of E. coli on five farms, giving a contamination level of 19.23%, and 40 (3.67%) strains of Salmonella on ten farms, with a contamination level of 38.46%. These high prevalences highlight, for the first time to the authors' knowledge, the contamination levels of the broiler chicken and traditional chicken value chains by Salmonella and E. coli in N'Djamena and Doba.

Study of the impact of waste glasses types on pozzolanic activity of cementitious matrix

This paper deals with glass packaging and especially with different types of wastes from its recycling (Valued Product (VP), End-of-Wash Waste (EWW) and Optical Sorting (OS)), in order to make a comparative study of their pozzolanic activity and leaching behaviour for an environmental study. VP is used by industrials in the production of new packaging glass, and EWW and OS are residues which are not currently valued, so considered as undesirable parts. First of all, these three materials have been crushed to obtain a homogeneous particle-size distribution (with d50 = 6.5 µm). Then, they have been physically and chemically characterized by helium pycnometer (absolute density), gas adsorption method (specific surface), X-ray crystallography and X-ray Fluorescence for chemical composition. The second step of this study involves making 4 × 4 × 16 cm specimens according to standard NF EN 196-1 in order to compare a reference mortar (RM) with 100% of cement 42.5 R with samples including the three types of waste glass (VP, EWW and OS) in partial substitution of cement. Leaching tests performed on these wastes according to standard NF EN 12457-2 allowed to highlight a correlation between mobility of silicon, aluminium and calcium, and the mechanical performances obtained. Finally, SEM observations and study of cement paste in fresh state allowed to give an explanation of the results observed in macroscopic scale.

A flame retarded chitosan binder for insulating miscanthus/recycled textile fibers reinforced biocomposites

ABSTRACTThe main objective of this study is devoted to the development of new insulating and ignifuged miscanthus fibers (Mf)/recycled textile fibers (RTf) reinforced biocomposites (BCs) using chitosan as polysaccharide‐based binder and aluminum trihydroxide (ATH) fillers while focusing on the fire behavior. To achieve this goal, a preliminary study was carried out on flame retarded chitosan‐based films with various ATH‐filler ratios (20, 33, 50, and 60 wt %). ATG and pyrolysis‐combustion flow calorimeter analysis showed significant improvement of chitosan thermal behavior with the addition of 33 wt % and above of ATH. Mechanical properties of films were, however, degraded. Thereafter, different ratios of miscanthus/RTf reinforced BCs (fibers content up to 89.5–90 wt %) were elaborated through thermocompression process using neat chitosan and chitosan/ATH (67/33 wt %) as a binder. Mechanical, thermal, and fire behavior were evaluated. Higher mechanical properties were found for hybrid materials containing the association of both RTf and Mf in comparison to those containing only RTf or Mf. Fireproof BCs (E rating: according to the NF EN ISO 11925‐2), with thermal conductivity values between 0.07 and 0.09 W m−1 K−1 and density range between 270 and 299 kg m−3 were successfully elaborated. The results of this study show a promising use of the chitosan/ATH system as flame retardant for biobased insulating building materials. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47306.

Harmonisation du système de management de la qualité au sein d’un laboratoire de biologie médicale hospitalo-universitaire

In the frame of the accreditation of the laboratories of medical biology, teaching hospitals laboratories stands in a particular place. Their diversity and specialization in terms of biological specialties are major. They make it hard to imagine that high output automated biochemistry tests are subject to the same requirements than more specialized manual methods. This article presents how, by using simple tools and by mastering their transmission, a teaching hospital laboratory can obtain the accreditation using the NF EN ISO 15189 norm.

Effect of steel hanger height on its members’ internal forces due to wind loads: comparison between standards EN1991-1-4 and NV65

This paper presents a comparison between two standards, namely NF EN 1991-1-4/A1 (October 2010) of Eurocode 1 and NV65 (DTU P06-002) (February 2009), that estimate wind loads on steel structures. For that purpose, a typical steel hanger was designed and analysed using both standards. Five different heights for the designed hanger were considered going from five to 25 m with an increment of 5 m. The paper shows all obtained curves for the calculated internal forces (axial, shear, and bending moment) on the hanger elements for all studied cases when using both standards.

How overcome the lack of internal quality control for the analysis of crystalluria?

The study of the crystalluria is the search and the identification for crystals in urines. This multi-parametric study brings a precious help in the diagnosis and/or the follow-up of acquired or congenital lithiasis. The lack of the internal urinary quality control (IQC) makes the accreditation of this analysis, according to the NF EN ISO 15189 standard, particularly delicate. After a presentation of the three steps (pre-analytical, analytical and post-analytical) performed in the laboratory, the authors present some insights in order to mitigate the lack of the urinary IQC. These insights, particularly concern by the "misappropriation" of IQC, the elaboration of an "in house" IQC as well as by the evaluation of the external evaluation of the quality. Thanks to the implementation of these tools, it becomes easier to prove that the laboratory of medical biology masters the qualification, the authorization and the continuous preservation of the skills of the operators performing the study of the crystalluria.

THE QUALIFICATION OF CLIMATIC AND THERMOSTATIC CHAMBERS ACCORDING TO STANDARDS: FD X 15-140, NF EN 60068-3 AND THE REQUIREMENTS OF THE GOOD MANUFACTURING PRACTICES (GMP)

Today's equipment is the main link between the raw materials and the finished product, so it must be installed, operational and must be maintained in accordance with its design specifications. Whatever the sector of activity, the same principles apply to all equipment. The qualification of the equipment, which demonstrates their adaptation to the use in an appropriate way, is a prerequisite before the stage of the validation, which consists of studying its performances by means of certain criteria. Subsequently, it is necessary to ensure that the performance of the system is maintained during the application of the method in routine by using tests of system conformity and quality control samples.

Production of fiberboards from shives collected after continuous fiber mechanical extraction from oleaginous flax

ABSTRACTIn this study, fiberboards were produced from shives collected after continuous fiber mechanical extraction from oleaginous flax straw. Fiberboards were produced through thermo-pressing, and their mechanical and thermomechanical properties were studied, as well as their water resistance. The influence of two pretreatments for shives and lignin addition was investigated on the different properties. Boards obtained were all cohesive hardboards. The optimal board was obtained from fibers extruded from the shives and without addition of any supplementary lignin amount. Looking at its characteristics and standard NF EN 312, the latter perfectly complied with the requirements for type P1 boards, i.e., boards for general uses in dry conditions.

Mechanical behavior of the reinforced concrete frame with masonry filling Comportement mécanique des portiques en béton armé avec remplissage en maçonnerie

Masonry is often used in the most of reinforced concrete structure constructions as a filling material that is important on structural characteristics. Structural contribution in the calculations was neglected or misunderstood, mainly due to the lack of a practical calculation methods and an appropriate regulatory tool.The analysis of frames filled with masonry is very complex. This complexity is linked from one part to the difference in the nature of elements and its behavior that make up the masonry itself (brick and mortar) and their interaction, and on the other part, for the large dispersion that characterizes the bricks as well as the execution's quality parameters which make it difficult to define reliable criteria for the masonry. The objective of this work is to experimentally highlight the influence of the hollow brick masonry filler, commonly used in Morocco, on reinforced concrete frames subject to lateral stresses, to deepen understanding the seismic behavior of the masonry structures by evaluating the structural performance of a specimen wall. These experimental results will be compared to those found by modeling prototypes, using SAP 2000 software, based on various approaches and models as well as other results deduced from the other researchers. The experimental study was carried out according to standard NF EN 1052-3 on two reinforced concrete frames, of dimensions (2m X 1.6m), the one with the masonry filling, and the other without filling in order to determine the initial characteristic resistance to the shearing of the masonry walls. The obtained results showed that a filling has a beneficial effect on rigidity which can be doubled compared to an empty frame. in the same way the lateral resistance. But this effect is much contrasted; it depends a lot on the characteristics essentially of the materials (bricks and concrete). This is the main reason, which justifies the divergence of the results deduced from the nine models that we used.

Determination of procalcitonin (PCT) in micro-method on AQT90 FLEX® analyzer and in vitro stability study

Radiometer® has developed a point-of-care test for fast PCT measurement on whole blood in micromethod on a AQT90 FLEX® instrument. We have verified the analytical performances of the AQT90 FLEX® PCT assay in heparinized macrotube and EDTA microtube for pediatric use, according to modified French Society of Clinical Biology (SFBC) protocol to the requirements of the standard NF EN ISO 15189: 2012. The samples (n=61, 30 macrotubes, 31 microtubes) were analyzed by the Brahms Kryptor Compact Plus® reference method vs the AQT90 FLEX®. In a second step, we studied the stability of the PCT at room temperature for 24 h. A good correlation between the two methods on macro- or microtubes is observed (respectively r=0.990 and 0.993). The Bland-Altmann representations confirm the excellent correlation with a deviant, above the acceptable limit, which was calculated according to ISO 5725-6, for each type of tube and for the two concentration ranges (lower and greater than 1 ng/mL). The biases observed do not affect the clinical decision. No degradation of PCT after 24 h was demonstrated by the Mann and Whitney test on macro- and microtubes (p=0.50 and 0.34, respectively). The determination of PCT on AQT90 FLEX® has satisfactory analytical characteristics and can be used as point-of-care testing device on whole blood without pre-analytical treatment. In heparinized macrotube and EDTA microtube, the PCT is stable at room temperature up to 24 h.

Comparison of standardized methods for suspended solid concentration measurements in river samples

SSC (Suspended Solid Concentration) measurements in rivers are a complex scientific issue. Many questions arise on the spatial and temporal distribution of particles throughout a cross-section, on the properties of particles and grain-size, and also on the sediment transport capacity of streams and rivers. In this study, we focused on the SSC and grain size distribution measured from river samples, automatically or manually acquired. Many agencies suggested slightly different methods for measuring SSC: The European standard NF EN 872, which related to the US EPA 160.2 requires sub-sampling using shake-and-pour aliquot selection. The APHA 2540D requires sub-sampling by pipetting at middepth in the original sample shaken with a magnetic stirrer. These methods lead to significant uncertainty when particles larger than 63 μm are present in the samples. The ASTM D3977 analysis method, endorsed by the USGS is more accurate to capture and quantify particles larger than 63 μm. In this study we confirm the sub-sampling problem in a large concentration range using a set of samples from an alpine river.

Experimental platform for outdoor characterization of photovoltaic modules under hot climate

This paper presents a novel test facility for outdoor characterization of photovoltaic modules. The test facility named “I-V bench” has been recently installed, within a sudano sahelian climate, in Ouagadougou (Burkina Faso). Our principal aim with this bench is to carry out different studies on photovoltaic energy productivity through the characterization of PV modules in real operating conditions. The experimental platform can receive up to 24 modules, from 1 Wp to 600 Wp that can be simultaneously monitored. In this paper, the principle of the operation of the test-bench is described. Then, current and voltage (I-V) data collected with the bench are used to find out the STC values of three different performance settings (open circuit voltage, short circuit current and maximum power) of PV modules. Several methods are proposed in the literature to translate outdoor values into standard conditions ones. Here, a comparison of results obtained with three methods, includitang the standard NF EN 60891: 1995-02, is performed. It has been shown that although the I-V data translation with model L5P leads to good accuracy, the best results for all photovoltaic parameters are obtained with the standard NF EN 60891: 1995-02.

Optimizing mortar extrusion using poplar wood sawdust for masonry building block

The wood industry generates some 12 million tons of waste in France, 60% of which basically stems from sawmills. The reuse of this waste in the most common construction materials (e.g., concrete) may offer a sustainable solution. In the literature, the optimization of composites formulations generally focuses on aggregates plant pretreatment regardless of classical optimization parameters and the implementation process that can afford to get a high strength composite. The work presented herein is intended to optimize the mix design of a mortar made from poplar wood by-products, without involving any pretreatment. The conventional mix design parameters (i.e., paste volume, W/C ratio) have been varied. An optimal implementation technique (i.e., extrusion) was used. The wood mortar mix designs have been optimized in order to obtain composites compliant with French standard NF EN 771-3/CN, with respect to criteria regarding both dimensional tolerance and mechanical strength for structural elements (i.e., above 8 MPa at 7 days).A mortar mix design, optimized by means of extrusion, has been used as a reference. Poplar wood particles have been introduced through substitution for the sand volume. Test results indicate that the blocks produced from two wood mortar mixes with 60 and 70% wood aggregate-for-sand substitution rates are in line with the normative requirements relative to dimensional tolerances and mechanical strength. This material compliance underscores the potential use of such blocks as load-bearing masonry elements, thus facilitating the building of structures with a limited environmental impact.