European Norm Research Articles

Practical fatigue analysis of hydraulic cylinders – Part II, damage mechanics approach

The paper is continuation and extension of the previous article (Marczewska et al., 2006) [1] published in Journal of Fatigue in 2006. Our previous model of analysis (Marczewska et al., 2006) [1] was based on classical S–N curves and equivalent amplitude stress concept. Now more physically justified damage mechanics approach to fatigue analysis is applied. The analysis used in both our papers is based on particular application of the constitutive model described in Oller et al. [2]. Hydraulic cylinders investigated under E.C. project “PROHIPP” are analyzed. Modeling of fatigue crack propagation is performed. The new elements, in comparison with previous paper (Marczewska et al., 2006) [1] are: application of the thermodynamic basics of damage mechanics approach to fatigue analysis with taking into account plastic deformations, introduction of damage evolution surface in fatigue analysis, modification of analytical form of S–N curve proposed in Oller et al. [2] and fatigue crack propagation modeling using damage mechanics approach. As it was mentioned in Marczewska et al. [1] the “marriage” of stress analysis and fatigue data is still one of deficiencies in the current European Norm EN 13445, chapter 18: detailed assessment of fatigue life [3]. Our paper is an attempt to further reduce this deficiency.

RE: Extracorporeal circulatory systems in the interhospital transfer of critically ill patients: experience of a single institution

RE: Extracorporeal circulatory systems in the interhospital transfer of critically ill patients: experience of a single institution

Impact of the amount of hand rub applied in hygienic hand disinfection on the reduction of microbial counts on hands

Two different hand rubs were tested in order to investigate the minimum volume required for microbicidal efficacy according to the European Norm EN 1500; we also sought to determine whether there is a correlation with hand size. Eight male volunteers with big hands (mean 184 cm(2)) and eight female volunteers with significantly smaller hands (mean 148 cm(2); P<0.001) participated in our study. Application of 2 mL of both products (P) provided mean log(10) reductions significantly smaller than those of the reference disinfectant (R) (product A: P=3.34, R=4.00, P=0.001; product B: P=3.37, R=3.75, P=0.022). Higher volumes (product A: 3 and 4 mL; product B: 2.5, 3 and 4 mL) ensured that the pass criteria of the European Norm (EN) 1500 were fulfilled. For both products log(10) reductions increased with increasing product volume until a plateau was reached. For the smaller female hands, this plateau level was reached after applying 3 mL of product A and 2.5 mL of product B. The plateau level on male hands was observed after treating the hands with > or =4 mL of product A and 3 mL of product B. The increase in product volume also correlated with the decrease in the number of volunteers considering the product volume applied as insufficient. In conclusion, the applied volume for hygienic hand rub should not fall below 3 mL in order to achieve maximum benefit.

Impacts of alcohol type, ratio and stirring time on the biodiesel production from waste canola oil

The use of alternative fuels in order to reduce the environmental impacts of diesel emissions has been extensively investigated. Trends in the regional use of biomass-derived fuels, such as alcohols, biodiesel and agricultural residues as a proposed control initiative against elevated carbon monoxide levels in urban areas have expanded to a global scale. Waste cooking oil is considered as the most suitable material due to its readily-availability and cost-effectiveness. In this study, the transesterification of waste canola cooking oil was carried out using lower alcohol to oil molar ratios to study its feasibility. Some important variables such as volumetric ratio, types of reactants and shaking time were selected to obtain a high quality biodiesel fuel with the specification of American Standard for Biodiesel Testing Material (ASTM D 6751) and European Norm (EN 14214). The highest biodiesel yield was obtained (49.5%) under conditions of 1:1 volumetric oil-to-methanol weight ratio, 0.5% NaOH catalyst at 55°C reaction temperature and 250 rpm stirring speed. The results showed that biodiesel production from different oil to methanol ratio, alcohol types and shaking time exhibited considerable differences. There was also a considerable difference of biodiesel yield produced by methanol, ethanol and 1-butanol. The biodiesel yield increased in the order of 1-butanol < ethanol <methanol. There was little difference in viscosity, acid value and chemical elements (Fe, Mg, Ca, Na, P etc.) at different parameters. The result showed that the optimal combination which could give highest production of biodiesel was transesterification, carried out for 2 h by using methanol to oil molar ratio of 1:1, catalyzed by 0.5% sodium hydroxide and produced biodiesel can be used as fuel in diesel engine.

Acacia mangium Tannin as Formaldehyde Scavenger for Low Molecular Weight Phenol-Formaldehyde Resin in Bonding Tropical Plywood

One of the limitations in using low molecular weight phenol-formaldehyde (LmwPF) resin as a binder for wood-based panels is the amount of the free formaldehyde being emitted during soaking, pressing and sometimes during the earlier stage of application. Tannin from bark extracts is rich in phenolic compounds, and thus may be able to absorb this free formaldehyde and at the same time provide strength to the joint. In this study, tannin–phenol-formaldehyde adhesives were prepared by blending Acacia mangium bark extracts (40% solids) with low molecular weight phenol-formaldehyde (40% solids at 1:1 ratio). The tannin–LmwPF adhesive produced cured within 4 min at 130°C, reduced the free formaldehyde to level E1 of European norm EN-120. The 3-ply plywood had acceptable shear strength (>1.0 MPa) exceeding the minimum requirements of European norms EN-314-1 and EN-314-2:1993 for interior and exterior applications, respectively. The study has shown that Acacia mangium tannin can be used as formaldehyde scavenger in LmwPF resin without compromising the strength of the joints.

La compatibilidad de la normativa catalana de seguridad industrial con la Directiva europea de servicios y su transposición legislativa en España

La Directiva europea de servicios en el mercado interior establece la libertad de entrada para las actividades económicas. Esta normativa ha sido objeto de transposición en España mediante las Leyes 17/2009 y 25/2009. No se prevé un régimen especial para la garantía de la seguridad industrial. Los organismos de control, pueden quedar sujetos a autorización administrativa bajo estrictas condiciones de igualdad y proporcionalidad. La Comunidad Autónoma de Cataluña ha mantenido su normativa (anterior y posterior) en clara contradicción con las normas del Estado y con los principios de derecho europeo.

Effects of Nanoclay as a Reinforcement Filler on the Physical and Mechanical Properties of Wood-based Composite

In this study, the effects of nanoclay (layered silicate) loading (0, 2, 4, 6, 8 wt%) as reinforcement filler and press temperature (165 and 175 °C) on the properties of laboratory made medium density fiberboard (MDF) boards were investigated. Physical (thickness swelling) and mechanical properties of the boards were determined according to the procedure of European Norm standards. The results showed considerable improvement in mechanical properties, specifically in bending strength and internal bond strength of the boards as nanoclay was loaded from 2 to 6 wt% to the boards’ furnishes. The boards with 6 wt% nanoclay content showed the optimized mechanical properties. There was a clear trend that both thickness swelling (after 2 and 24 h water soaking) decreased with addition of nanoclay and press temperature. The increasing press temperature had strong positive effect on all physicomechanical properties of the boards. Thus, the data showed that nanoclay can enhance mechanical strength and water stability properties of MDF boards.

Correlation for the estimation of the cetane number of biodiesel fuels and implications on the iodine number

Some European experts on normalization of transport fuels have recently suggested the suppression of the cetane-number limitation from the European biodiesel norm when its final destination is blending with diesel fuel. Although this measure should not affect the range of oils used for biodiesel production (only few of them lead to biodiesel fuels with cetane numbers below this limit), the trend of cetane number to decrease with increasing unsaturation could reinforce the arguments to maintain the iodine-number limitation as an indirect limit for the cetane number. The iodine number has frequently been subjected to controversy because its stringent limitation in Europe prevents from using differently unsaturated fatty oils for biodiesel production. Some of the arguments in favour of extending or eliminating the iodine-number limitation in the norm are exposed here. Previously, a correlation for the estimation of the cetane number based on a literature review is proposed. From this correlation, a procedure is proposed for the estimation of the limiting effect of the current cetane-number limitation on the unsaturation degree of biodiesel fuels. Finally, the impact of the elimination of the cetane-number limitation on the use of different oils for biodiesel production is analyzed.

Incidence of Microperforation for Surgical Gloves Depends on Duration of Wear

The use of sterile gloves is part of general aseptic procedure, which aims to prevent surgical team members from transmitting infectious agents to patients during procedures performed in an operating room. In addition, surgical gloves also protect team members against patient-transmitted infectious agents. Adequate protection, however, requires that the glove material remain intact. The risk of perforations in surgical gloves is thought to correlate with the duration of wear, yet very few prospective studies have addressed this issue. We prospectively collected 898 consecutive pairs of used surgical gloves over a 9-month period in a single institution. After surgical team members wore the gloves during surgical procedures, the gloves were examined for microperforations using the watertight test described in European Norm 455, part 1. The gloves were analyzed as a pair; if 1 glove had a perforation, the pair was considered to be perforated. In addition, we evaluated the use of a hand cream that contained a suspension of cornstarch and ethanol to determine its potential influence on the rate of microperforation. Wearing gloves for 90 minutes or less resulted in microperforations in 46 (15.4%) of 299 pairs of gloves, whereas wearing gloves for 91-150 minutes resulted in perforation of 54 (18.1%) of 299 pairs, and 71 of (23.7%) of 300 pairs were perforated when the duration of wear was longer than 150 minutes (P = .05). Subgroup analysis revealed no significant difference in the rates of microperforation for surgeons (56 [23.0%] of 244 pairs of gloves perforated), first assistants (43 [19.0%] of 226 pairs perforated), and surgical nurses (53 [20.5%] of 259 pairs perforated). Of 171 microperforations, 114 (66.7%) were found on the left hand glove (ie, the glove on subjects' nondominant hand), predominantly on the left index finger (55 [32.3%]). The use of the hand cream had no influence on the rate of microperforation. Because of the increase in the rate of microperforation over time, it is recommended that surgeons, first assistants, and surgical nurses directly assisting in the operating field change gloves after 90 minutes of surgery.

Surgical Hand Antisepsis With Alcohol-Based Hand Rub Comparison of Effectiveness After 1.5 and 3 Minutes of Application

Research has shown 1.5 minutes of surgical hand antisepsis with alcohol-based hand rub to be at least as effective under experimental conditions as the 3-minute reference disinfection recommended by European Norm 12791. The aim of the present study was to validate the effectiveness of 1.5 minutes of surgical hand antisepsis in a clinical setting by comparing the effectiveness of 1.5- and 3-minute applications of alcohol-based hand rub (45% vol/vol 2-propanol, 30% vol/vol 1-propanol, and 0.2% mecetronium ethylsulphate). Prospective crossover trial in which each surgeon served as his or her own control, with individual randomization to the 1.5- or the 3-minute group during the first part of the trial. Basel University Hospital, Switzerland. Thirty-two surgeons with different levels of postdoctoral training. We measured the bactericidal effectiveness of 1.5 minutes and 3 minutes of surgical hand antisepsis with alcohol-based hand rub by assessing the mean (+/-SD) log10 number of colony-forming units before the application of hand rub (baseline), after the application of hand rub (immediate effect), and after surgery (sustained effect) so as to follow European Norm 12791 as closely as possible. The immediate mean (+/-SD) log10 reduction in colony-forming units (cfu) was 2.26 +/- 1.13 log10 cfu for the 1.5-minute group and 3.01 +/- 1.06 log10 cfu for the 3-minute group (P = .204). Similarly, there was no statistically significant difference between the 2 groups with respect to the sustained effect; the mean (+/-SD) log10 increase in bacterial density during surgery was 1.08 +/- 1.13 log10 cfu for the 1.5-minute group and 0.95 +/- 1.27 log10 cfu for the 3-minute group (P = .708). No adverse effects were recorded. In this clinical trial, surgical hand antisepsis with alcohol-based hand rub resulted in a similar bacterial reduction, regardless of whether it was applied for 3 or 1.5 minutes, which confirms experimental data generated with healthy volunteers.

The qualitative evaluation of cost effective one test-run determination of aromatic hydrocarbons and fatty acid methyl esters content in fossil diesel fuels by high performance liquid chromatography

A high performance liquid chromatography method was developed for quantifying blends of biodiesel (fatty acid methyl esters) in fossil diesel fuel. The qualitative evaluation of a one test-run determination for aromatic hydrocarbons and fatty acid methyl esters content shows that the developed test method gives accurate and reliable test results in the range from 0.3% (m/m) to 30% (m/m) for fatty acid methyl esters content. The uncertainty for the determination of biodiesel (fatty acid methyl esters) content is comparable to the evaluated uncertainty for the standardized test procedure using infrared spectroscopy prescribed in the European norm for fossil diesel fuel.

Utilization of jarosite/alunite residue for mortars restoration production

The present study was carried out to produce artificial hydraulic lime mortars for repair and conservation of historic masonry using a jarosite/alunite precipitate, a waste product of a novel Greek hydrometallurgical process developed to treat economically low grade nickel oxides ores. Alternative mortars were prepared by mixing lime powder, quartz sand and the above residue, substituting lime up to 50%. The mortars were prepared and tested according to European Norm EN 1015. They were cured for periods of 28 and 90 days and the compressive and flexural strengths were determined. The best mechanical behavior was observed for the mortar with 50% lime replacement, which also presented a low ratio of compressive to flexural strength (f c/f f). X-Ray diffraction, TG-DTA and mercury porosimetry were used to characterize the hydration products at 28 and 90 days. The results showed that the jarosite/alunite residue was dissolved in the high alkaline environment of the mortar, producing CaSO4 · 2H2O and AlOOH. During hydration, gypsum and some of the Ca(OH)2 were consumed, together with aluminum hydroxide in order to produce ettringite, a fact that improved the mechanical behavior of the produced mortars.

Perforation resistance of five different high-strength steel plates subjected to small-arms projectiles

Thin plates of high-strength steel are frequently being used both in civil and military ballistic protection systems. The choice of alloy is then a function of application, ballistic performance, weight and price. In this study the perforation resistance of five different high-strength steels has been determined and compared against each other. The considered alloys are Weldox 500E, Weldox 700E, Hardox 400, Domex Protect 500 and Armox 560T. The yield stress for Armox 560T is about three times the yield stress for Weldox 500E, while the opposite yields for the ductility. To certify the perforation resistance of the various targets, two different ballistic protection classes according to the European norm EN1063 have been considered. These are BR6 (7.62 mm Ball ammunition) and BR7 (7.62 mm AP ammunition), where the impact velocity of the bullet is about 830 m/s in both. Perforation tests have been carried out using adjusted ammunition to determine the ballistic limit of the various steels. In the tests, a target thickness of 6 mm and 6 + 6 = 12 mm was used for protection class BR6 and BR7, respectively. A material test programme was conducted for all steels to calibrate a modified Johnson–Cook constitutive relation and the Cockcroft–Latham fracture criterion, while material data for the bullets mainly were taken from the literature. Finally, results from 2D non-linear FE simulations with detailed models of the bullets are presented and the different findings are compared against each other. As will be shown, good agreement between the FE simulations and experimental data for the AP bullets is in general obtained, while it was difficult to get reliable FE results using the Lagrangian formulation of LS-DYNA for the soft core Ball bullet.

Occurrence of aflatoxin M(1) in dairy products in southern Italy.

A screening survey of the presence of aflatoxin M1 (AFM1) was carried out on 265 samples of cheese made from cow, buffalo, goat, sheep, sheep-goat milk collected in the Apulia region (Southern Italy). Selected samples included unripened, medium and long-term ripened cheeses. AFM1 was found in 16.6% of the analyzed samples. The highest positive incidence was for medium and long-term ripened cheeses, especially those made from sheep-goat milk, while buffalo cheeses tested consistently negative. Our results show that the level of contamination by AFM1 in dairy products from Apulia Region are lower than in other Italian and European regions. Moreover, it is important to underline that a common European norm concerning the AFM1 threshold limits for dairy products is still lacking.

Mineralogy and environmental stability of slags from the Tsumeb smelter, Namibia

Three types of smelting slags originating from historically different smelting technologies in the Tsumeb area (Namibia) were studied: (i) slags from processing of carbonate/oxide ore in a Cu–Pb smelter (1907–1948), (ii) slags from Cu and Pb smelting of sulphide ores (1963–1970) and (iii) granulated Cu smelting slags (1980–2000). Bulk chemical analyses of slags were combined with detailed mineralogical investigation using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM/EDS) and electron microprobe (EPMA). The slags are significantly enriched in metals and metalloids: Pb (0.97–18.4 wt.%), Cu (0.49–12.2 wt.%), Zn (2.82–12.09 wt.%), Cd (12–6940 mg/kg), As (930–75,870 mg/kg) and Sb (67–2175 mg/kg). Slags from the oldest technology are composed of primary Ca- and Pb-bearing feldspars, spinels, complex Cu–Fe and Cu–Cr oxides, delafossite–mcconnellite phases and Ca–Pb arsenates. The presence of arsenates indicates that these slags underwent long-term alteration. More recent slags are composed of high-temperature phases: Ca–Fe alumosilicates (olivine, melilite), Pb- and Zn-rich glass, spinel oxides and small sulphide/metallic inclusions embedded in glass. XRD and SEM/EDS were used to study secondary alteration products developed on the surface of slags exposed for decades to weathering on the dumps. Highly soluble complex Cu–Pb–(Ca) arsenates (bayldonite, lammerite, olivenite, lavendulan) associated with litharge and hydrocerussite were detected. To determine the mineralogical and geochemical parameters governing the release of inorganic contaminants from slags, two standardized short-term batch leaching tests (European norm EN 12457 and USEPA TCLP), coupled with speciation-solubility modelling using PHREEQC-2 were performed. Arsenic in the leachate exceeded the EU regulatory limit for hazardous waste materials (2.5 mg/L). The toxicity limits defined by USEPA for the TCLP test were exceeded for Cd, Pb and As. The PHREEQC-2 calculation predicted that complex arsenates are the most important solubility controls for metals and metalloids. Furthermore, these phases can readily dissolve during the rainy season (October to March) and flush significant amounts of As, Pb and Cu into the environment in the vicinity of slag dumps.

Influence of rub-in technique on required application time and hand coverage in hygienic hand disinfection.

BackgroundRecent data indicate that full efficacy of a hand rub preparation for hygienic hand disinfection can be achieved within 15 seconds (s). However, the efficacy test used for the European Norm (EN) 1500 samples only the fingertips. Therefore, we investigated hand coverage using sixteen different application variations. The hand rub was supplemented with a fluorescent dye, and hands were assessed under UV light by a blind test, before and after application. Fifteen non-healthcare workers were used as subjects for each application variation apart from one test which was done with a group of twenty healthcare workers. All tests apart from the reference procedure were performed using 3 mL of hand rub. The EN 1500 reference procedure, which consists of 6 specific rub-in steps performed twice with an aliquot of 3 ml each time, served as a control. In one part of this study, each of the six steps was performed from one to five times before proceeding to the next step. In another part of the study, the entire sequence of six steps was performed from one to five times. Finally, all subjects were instructed to cover both hands completely, irrespective of any specific steps ("responsible application"). Each rub-in technique was evaluated for untreated skin areas.ResultsThe reference procedure lasted on average 75 s and resulted in 53% of subjects with at least one untreated area on the hands. Five repetitions of the rub-in steps lasted on average 37 s with 67% of subjects having incompletely treated hands. One repetition lasted on average 17 s, and all subjects had at least one untreated area. Repeating the sequence of steps lasted longer, but did not yield a better result. "Responsible application" was quite fast, lasting 25 s among non-healthcare worker subjects and 28 s among healthcare workers. It was also effective, with 53% and 55% of hands being incompletely treated. New techniques were as fast and effective as "responsible application". Large untreated areas were found only with short applications. Fingertips and palms were often covered completely.ConclusionIn clinical practice, hand disinfection is apparently better than practitioners of infection control often anticipate. Based on our data, a high-quality hygienic hand disinfection is not possible within 15 s. A 30 s application time can, however, be recommended for clinical practice. The currently recommended six steps of EN 1500 are not really suitable for clinical practice, because they yield comparably poor results. The most appropriate application procedure may be "responsible application", or one of the other new techniques.

Determination of allergy-causing metals from coins

The majority of everyday items contain metals and their alloys, although many of them may be harmful to human health. Nickel, originating from different sources such as coins, jewelry, or buttons, represents the most common cause of contact allergy dermatitis. Therefore, the aim of this research work was to estimate the possible risk of allergy resulting from skin exposure to coins. In order to obtain information on the amounts of metals released by their daily use, extraction experiments of coins were per- formed applying an artificial acidic sweat solution during varying extraction periods. After extraction, the mass of the metals released (copper, iron, nickel, and zinc) were determined by inductively coupled plasma-optical emis- sion spectrometry (ICP-OES). The mass rate of Ni extracted per area considerably exceeded the permissible values according to the European norm: 50 times for 50- lipa coins, 80 times for 20-lipa coins, and 110 times for 1-kuna coins. This indicates that nickel-containing coins may represent a serious health hazard, especially to sen- sitive people.

Comparative review of the test design Tentative Final Monograph (TFM) and EN 12791 for surgical hand disinfectants

Preoperative antiseptic treatment of the hands of the surgical team is a standard procedure used worldwide in order to reduce the risk of surgical site infection. Two different types of antiseptics are available: alcohol-based hand rubs and antimicrobial liquid detergents ("soaps"). Standards have been developed to determine the antimicrobial efficacy of such preparations: the European norm EN 12971, finally issued in 2005, and the Tentative Final Monograph (TFM) for health care antiseptic products from 1994, which is the corresponding document in the USA. Although both methods use the reduction of resident hand flora as a quantitative parameter for antimicrobial efficacy, there are major differences concerning the test design. Whereas the European method is carried out following a randomized, reference-controlled crossover design, the US method can be characterized as a randomized, blinded parallel arm design. While both standards aim at immediate as well as sustained efficacy of the procedure, according to the EN the test product must not be significantly less effective than the reference procedure, whereas the TFM requires absolute reduction of > or = 1, > or = 2, and > or = 3 log10 per hand on days 1, 2, and 5, respectively. Results from various studies demonstrated that meeting the criteria defined by both standards may happen, but meeting the specifications of one standard does not necessarily mean that the same product will pass the requirements of the other. Missing accordance may be due to a number of considerable differences between both test methods. For a number of reasons the European method seems to be closer to clinical practice and to provide higher patient safety than the US method. However, available study data do neither allow for evaluation of the clinical impact of surgical hand disinfection as such nor of the effect of a particular product on postoperative wound infection rates.

Lachgasbedingte Todesfälle

Despite inspiratory oxygen fraction measurement being regulated by law in the European norm EN 740, fatal errors in nitrous oxide delivery still occur more frequently than expected, especially after construction or repair of gas connection tubes. Therefore, if nitrous oxide is to be used further in a hospital, all technical measures and system procedures should be employed to avoid future catastrophes. Among these are measurement of the inspiratory oxygen fraction (F(I)O(2)) and an automatic limitation of nitrous oxide. Also all anaesthetists involved should be informed about repair or construction of central gas supply tubes. Additionally, more awareness of this problem in daily routine is necessary. Furthermore, a system of detecting and analysing errors in anaesthesia has to be improved in each hospital as well as in the anaesthesia community as a whole. Measures for a better "error culture" could include data exchange between different critical incident reporting systems, analysis of closed claims, and integration of medical experts in examination of recent catastrophes.

The potential of downscaled dynamic column extraction for fast and reliable assessment of natural weathering effects of municipal solid waste incineration bottom ashes

There is a current worldwide interest for evaluating the potential reuse of municipal solid waste incineration (MSWI) bottom ash as a sub-base in road construction and secondary building material. Yet, there is a need for exploration of the physicochemical features of the bottom ashes to ensure environmental sustainability. To this end, batchwise water extraction as promulgated by the European norm EN 12457 or the German DIN 38414-S4 tests is commonly utilized to ascertain the impact of leachable trace elements in bottom ashes on biota. However, the above extraction protocols are not properly simulating the dynamic extraction conditions occurring in the nature, whereby the analytical information provided for risk assessment is debatable. In this work, a downscaled flow-through extraction method is proposed for mimicking the leaching of hazardous trace elements (namely, Pb, Zn, Cd, Cu and Cr) in MSWI bottom ashes by runoff waters more accurately than the manual counterparts. The flow assembly facilitates the full automation of standard and regulatory leaching tests by packing of a suitable amount of solid material into a column, whereupon the leaching reagent is continuously pumped through, thus yielding an accurate assessment of the environmentally significant water-extraction fraction with no effect from readsorption phenomena. The flow-through column system is exploited as a screening tool for fast evaluation of the influence of natural bottom ash weathering on the immobilization of hazardous elements to dictate the potential reuse of the solid waste. The dependence of sorption sites for humic substances on trace element leachability is also discussed. As compared to the steady-state approach, the dynamic method features the substantial shortening of the analytical extraction protocol from 24 h to just 30 min, better precision, with relative standard deviations (R.S.D.) <11% versus >20% R.S.D. for batchwise extraction, improved accuracy because of the absence of metal redistribution phenomena and minimization of manual operations as well as straightforward investigation of leaching rates for the suite of target elements.