European Co-operation For Accreditation Research Articles

Methodology and Analysis of the ILCs Provided by INRIM from 2016 to 2018

To assess the technical competence of calibration laboratories, national accreditation bodies (NABs) take into account the results of national and/or international proficiencies testing (PTs) including the inter-laboratory comparisons (ILCs). As the Italian NAB stopped acting as PT provider since 2015 due to the result of a peer assessment by the European co-operation for accreditation, the National Institute of Metrological Research (INRIM) reorganized itself and reoriented part of its activity to become a ILCs provider, thus supporting the calibration laboratories. This paper describes how INRIM has been organized as ILCs provider to guarantee the accreditation activity continuation and gives information about the main typologies of the provided ILCs and details on the analysis of the ILCs results in different metrological areas. From 2016 to 2018, INRIM provided 114 ILCs, in the areas of acoustics ultrasonic and vibration, electricity and magnetism, length (L), mass (M) and thermometry (T), involving 138 laboratories, for which 375 ILC reports were issued.

Experience of the implementation of EA-4/18

The standard ISO/IEC 17025 (sub-clause 5.9) requires that the validity of tests results is monitored by laboratories and one of the tools that can be used is the participation in proficiency testing (PT). To give guidance to accreditation bodies (ABs) on how to evaluate the level and frequency of participation in PT and to assist laboratories in determining their own levels and frequency of participation, a guidance document, EA-4/18 (Guidance on the level and frequency of proficiency testing participation), was established in 2010 by the European Cooperation for Accreditation (EA). There has been various feedback from the analytical community in Europe suggesting that some laboratories have experienced mixed messages from different assessors as to the level and frequency of PT participation required and that there may be a lack of harmonization between accreditation bodies. Given the concerns raised, the EEE-PT (EA-Eurachem-Eurolab) WG undertook a survey, with the support of the EA Laboratory committee, to ascertain the experience from the EA accreditation bodies with implementing the guidance. The survey was sent to the EA full and associate members. The outcome of the survey showed that EA-4/18 is implemented in a harmonized way throughout the accreditation bodies, but the concept included in EA-4/18 can be difficult to understand. As there are no specific indications in EA-4/18, on the level and frequency of participation, the implementation by each laboratory of the concept found in EA-4/18 can vary, even if the laboratories are active in the same field. In the same way, different assessors can have different views on the strategy established by the laboratory, therefore leading to the impression that the laboratories are treated differently. A majority of ABs wish to revise EA-4/18 as it is considered as a helpful guidance, but more clarification of the concept and additional examples should be included in the revised version, if EA decides to do so.

ISO 15189 Accreditation: Navigation Between Quality Management and Patient Safety.

SummaryAccreditation is a valuable resource for clinical laboratories and the development of an International Standard for their accreditation represented a milestone on the path towards improved quality and safety in laboratory medicine. The recent revision of the International Standard, ISO 15189, has further strengthened its value not only for improving the quality system of a clinical laboratory but also for better answering the request for competence, focus on customers’ needs and ultimate value of laboratory services. Although in some countries more general standards such as ISO 9001 for quality systems or ISO 17025 for testing laboratories are still used, there is increasing recognition of the value of ISO 15189 as the most appropriate and useful standard for the accreditation of medical laboratories. In fact, only this International Standard recognizes the importance of all steps of the total testing process, namely extra-analytical phases, the need to focus on technical competence in addition to quality systems, and the focus on customers’ needs. However, the number of accredited laboratories largely varies between European countries and also major differences affect the approaches to accreditation promoted by the national bodies. In particular, some national accreditation bodies perpetuate the use of fixed scopes, while the European co-operation for accreditation (EA) and the European Federation of Laboratory Medicine (EFLM) Working Group promote the use of flexible scopes. Major issues in clinical laboratory accreditation are the verification of examination procedures for imprecision, trueness and diagnostic accuracy and for estimating measurement uncertainty. In addition, quality indicators (QIs) are a fundamental requirement of the ISO 15189 International Standard.

Flexible scope for ISO 15189 accreditation: a guidance prepared by the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group Accreditation and ISO/CEN standards (WG-A/ISO).

The recent revision of ISO15189 has further strengthened its position as the standard for accreditation for medical laboratories. Both for laboratories and their customers it is important that the scope of such accreditation is clear. Therefore the European co-operation for accreditation (EA) demands that the national bodies responsible for accreditation describe the scope of every laboratory accreditation in a way that leaves no room for doubt about the range of competence of the particular laboratories. According to EA recommendations scopes may be fixed, mentioning every single test that is part of the accreditation, or flexible, mentioning all combinations of medical field, examination type and materials for which the laboratory is competent. Up to now national accreditation bodies perpetuate use of fixed scopes, partly by inertia, partly out of fear that a too flexible scope may lead to over-valuation of the competence of laboratories, most countries only use fixed scopes. The EA however promotes use of flexible scopes, since this allows for more readily innovation, which contributes to quality in laboratory medicine. In this position paper, the Working Group Accreditation and ISO/CEN Standards belonging to the Quality and Regulation Committee of the EFLM recommends using an approach that has led to successful introduction of the flexible scope for ISO15189 accreditation as intended in EA-4/17 in The Netherlands. The approach is risk-based, discipline and competence-based, and focuses on defining a uniform terminology transferable across the borders of scientific disciplines, laboratories and countries.

Editorial: Special issue on the 7th Symposium of the EWDTS on Workplace Drug Testing

Workplace drug testing (WDT) is an interdisciplinary topic thus concerning not only people directly involved with the testing, i.e. laboratory personnel and collectors, but also employees and their representatives, human resources personnel, occupational physicians, risk assessors, compliance officers, lawyers (for the company and for the employees), drug counselling and treatment providers and policy-makers. The situation becomes more challenging when WDT needs to be performed in a heterogeneous continent as Europe is, with its different cultures, trade unions' influence, health and safety policies, languages and laws. This was realized as early as 1998, when the EWDTS was founded primarily to ensure that WDT in Europe is performed according to a defined quality standard and in a legally secured way and secondly to provide an independent forum for all aspects of WDT. The first aim is fulfilled via the formulation of drug and alcohol testing guidelines for urine,[1] hair,[2, 3] and oral fluid.[4, 5] The former two are already accepted by the European Co-operation for Accreditation, (EA) as advisory documents.[6] The oral fluid guidelines have been submitted to the EA and are waiting to be accepted. The second EWDTS goal is mainly achieved through the Society's biannual international symposia: in Huddinge, Sweden (1998), in Rimini, Italy (2000), in Barcelona, Spain (2003), in Dublin, Ireland (2005), in Stockholm, Sweden (2007), in Copenhagen, Denmark (2009), and the last one, held in Edinburgh, Scotland (2011). Thanks to John Wiley & Sons Ltd, this special issue contains 7 of the 21 sessions presented at this last meeting.

Developments in accreditation of flexible scopes in Europe

Accreditation of testing and calibration laboratories is the most frequently used type of accreditation. European Co-operation for Accreditation (EA) as the European network of recognised national accreditation bodies covers accreditation of all types of conformity assessment bodies. In Europe, the number of accredited testing and calibration laboratories covered under the EA Multilateral Agreement is about 15,000 nowadays.

TrainMiC®: Providing a Tool for the Inter-Calibration of Technical Assessors in Europe in the Area of Chemical Measurements

The TrainMiC® (Training in Metrology in Chemistry) programme is a European programme for Life-Long Learning in metrology in chemistry, which is a truly unique system operational across many parts of Europe (19 countries) via national teams. It uses shareware pedagogic tools and the learning content has been harmonised at the European level by a joint effort of many experts across Europe working via an Editorial Board. This paper gives an overview of the activities within the TrainMiC® programme where there is an interaction with national accreditation bodies and the European Cooperation for Accreditation. It is the responsibility of the accreditation bodies to ensure that outcome of the assessments is reliable and transparent and is meeting the relevant requirements. The paper explains the potential of TrainMiC® in providing a tool for accreditation bodies to ensure a harmonised level of knowledge in a specific sector of those who are involved in technical assessments for accreditation in the field of chemical measurements. Some use the word inter-calibration to describe this process.

Complex S-parameter measurement and its uncertainty evaluation on a vector network analyzer

The present paper deals with an uncertainty evaluation in complex scattering (S)-parameter measurements and the correlation coefficients between the real and imaginary components of S-parameters in the frequency range 2–18 GHz. The measurements were performed for one-port and two-port components using a vector network analyzer (VNA) and the uncertainty estimation for complex transmission and reflection coefficients were done separately. The various contributors to the measurement uncertainty in real and imaginary component of S-parameter have been evaluated as per the European cooperation for Accreditation (EA) Guidelines on VNAs. Uncertainty budgets have been provided for one/two-port components separately with various sources of uncertainties involved and their distribution. This paper reports the combined standard uncertainty within ±0.005 and ±0.015 in complex transmission and reflection coefficients, respectively, upto 18 GHz. The correlation coefficients (+1.0 to −1.0) between the real and imaginary components of S-parameters are calculated for a coaxial mismatch of voltage standing wave ratio (VSWR) ≈3.0 and a coaxial attenuator (3 dB) in Type-N connectors.

On the specific experience of national metrology institutes (NMIs) with national accreditation bodies (NABs)

The following paper addresses the experience of certain national metrology institutes (NMIs) with national accreditation bodies (NABs), in particular in small countries with emerging economies in new EU or candidate member states. Specific cases have been analysed primarily in some Central and South-East European countries. NABs under consideration are, in principle, members of European Co-operation for Accreditation (EA). EA cross-frontier policy in these cases will be discussed and resulting dilemmas outlined. Focus will be given to the problems of NMIs also performing calibrations, commercial calibration laboratories, and their relations with NABs. Due to numerous problems of smaller NABs, cross-frontier policy should stimulate cooperation between foreign and local accreditation bodies not only at the request of the calibration laboratory or some other conformity assessment body, but at the request of the local accreditation body in order to provide the best service for their local economy. As a solution to the accreditation problems, this paper proposes a process of gradual formation of a common European pool of experts, real-life common practices and, finally, maybe even some form of joint European accreditation service.

IMEP-12: trace elements in water; objective evaluation of the performance of the laboratories when measuring quality parameters prescribed in the European Directive 98/83/EC

The International Measurement Evaluation Programme (IMEP) is an interlaboratory comparison scheme, founded, owned and co-ordinated by the Institute for Reference Materials and Measurements (IRMM) since 1988. IMEP-12, for the fourth time in the series, focused on trace elements in water and it was designed specifically to support European Commission directive 98/83/EC. Reference values for the concentration of ten elements were established with expanded uncertainties according to GUM. In total, 348 laboratories from 46 countries in five continents participated in the comparison and the degree of equivalence between the results of the laboratories and the reference values is presented graphically. Samples from the same batch were distributed to ten laboratories from European Countries, which represented their country in the framework of the EUROMET project 528. Participation in this comparison was offered to the European Co-operation for Accreditation (EA) for participation of accredited laboratories from all over Europe in the framework of the collaboration between IRMM and EA and to laboratories from the EU new member states and acceding countries in the frame of IRMM’s ‘Metrology in Chemistry support program for EU new member states and acceding countries.’

Accreditation of medical laboratories in the European Union

Using a questionnaire, the EC4 (European Communities Confederation of Clinical Chemistry and Laboratory Medicine) has collated an inventory of the accreditation procedures for medical laboratories in the EU. Accreditation of medical laboratories in the countries of the EU is mostly carried out in cooperation with national accreditation bodies. These national accreditation bodies work together in a regional cooperation, the European Cooperation for Accreditation (EA). Professionals are trained to become assessors and play a prominent role in the accreditation process. The extent of the training is diverse, but assessors are kept informed and up-to-date by annual meetings. The frequency of assessments and surveillance visits differs from country to country and ranges from 1 to 4 years. More harmonisation is needed in this respect, based on a frequency that can be pragmatically handled by laboratory professionals. In the majority of EA bodies, accreditation is carried out on a test-by-test basis. Many professionals would prefer accreditation of the entire service provided within the actual field of testing (i.e., haematology, immunology, etc.), with accreditation granted if the majority of tests offered within a service field fulfil the requirements of the ISO 15189 standard. The scope of accreditation is a major point of discussions between the EC4 Working Group on Accreditation and representatives of accreditation bodies in the EA Medical Laboratory Committee.

A Review of the GUM Workbench

The GUM Workbench provides an extremely useful tool for computing uncertainties that result from combining individual uncertainty components into a single total uncertainty, in accordance with requirements specified by the European Co-operation for Accreditation. The program is fairly easy to use and yields good results, including full uncertainty budgets. Certain tasks, such as identifying and dealing with outliers, and computing variance components due to random effects, need to be done outside of the GUM Workbench prior to entering data. A free demonstration version is available.

Uncertainties associated with current measurements: Analysis by the finite element method

The paper analyses the effect of crosstalk magnetic fields in current measurement devices with magnetic cores, as clamp-type current meters and current transformers. FEM modelization was used to calculate relative errors due to the crosstalk currents and how these errors are affected by variables as permeability, non-linearities and distance. Experimental results are also reported, in order to validate the numerical calculations. The measurements were obtained using the resources of the LME (Electric Metrology Laboratory) of the Electrical Engineering Department of the University of Zaragoza, accredited by ENAC, a member of EA (European Co-operation for Accreditation).

Modelization of current sensors by finite elements method

Accurate high current measurements require the use of devices which are difficult to calibrate since neither it is easy to obtain the current needed nor to set up a proper testing rig in the laboratory. Nevertheless, a straight wire carrying a high current can be replaced by an N-turn coil fed with an N-times lower current. In this paper, the uncertainty associated with the use of N-turn coils in calibration of clamp-type current meters has been estimated using the finite element method (FEM). The wire carrying the current to be measured is often incorrectly located with respect to the sensor. Hence, the effects of excentricity or rotation of the sensor with respect to the straight wire are also analysed by FEM and measured at 50 Hz in our metrology laboratory accredited by European Cooperation for Accreditation (EA).

One way of disseminating reference values with demonstrated traceability and demonstrated uncertainty to field laboratories: IMEP

An operational interlaboratory comparison programme is described which disseminates SI-traceable reference values to laboratories worldwide. These reference values have an uncertainty and traceability that is demonstrated at the highest metrological level. Participating laboratories can use these values to establish the degree of equivalence of their measurement results and can use this to support their measurement capability claims, e.g. towards third parties. The programme has been run by the Institute for Reference Materials and Measurements (IRMM) since 1988, in the first phase as an awareness programme. Currently, IRMM is focusing its efforts on educational aspects of metrology via a collaboration with the European Co-operation for Accreditation, national metrological institutes (NMIs) and interested academic networks. The viewgraphs used are presented in the “Electronic Supplementary Material” of this ACQUAL issue.

Uncertainty in measurement of semiconductor piezoresistive sensors

The analysis of the measurement uncertainty of piezoresistive sensors should be performed according to the ISO “Guide to the Expression of Uncertainty in Measurement” (GUM) and the requirement document EAL-R2 of the `European co-operation for Accreditation of Laboratories'. In this work, the derivation of a model of the physical relationships between quantities in the respective measurement is demonstrated for the case of a piezoresistive sensor. The model is used to evaluate the uncertainty in measurement of semiconductor piezoresistive sensors.

EA, today and tomorrow

This article presents the European co-operation for Accreditation (EA) as it is to day and tries to focus on the main goals on which we will be challenged in the very near future.

Announcing the collaboration between the European co-operation for Accreditation and the Institute for Reference Materials and Measurements: Improving the metrological basis of the European accreditation system for chemical measurements

Announcing the collaboration between the European co-operation for Accreditation and the Institute for Reference Materials and Measurements: Improving the metrological basis of the European accreditation system for chemical measurements

Measurement uncertainty according to ISO/BIPM-GUM

In modern life, to make measurements comparable, stating the quality of a measurement in terms of the measurement uncertainty is an absolute necessity. The ISO/BIPM “Guide to the Expression of Uncertainty in Measurement”—usually referred to as the GUM or the Guide—, which was published in 1993, introduces a method to unify the evaluation and the statement of measurement uncertainties. This method has been accepted by almost all calibration services all over the world and has become a quasi-standard in the field of metrology. This paper deals with the background of the GUM, the knowledge of the respective measurement and other fundamental aspects which have been included in the EA-4/02 requirements document published by the European co-operation for Accreditation. It shows how the basic concepts may be converted in a straight forward procedure to evaluate the uncertainty in a measurement. It is an expanded version of a lecture with the same title, held by the author at the workshop “GUM uncertainty budget in calorimetry—questions and ways to realistic determinations of measurement uncertainty” at the 14th Ulm-Freiberg Kalorimetrietage in Freiberg (Saxony) March 21/23, 2001.

The flexible scope of accreditation

The scope of accreditation for testing laboratories can inhibit, in certain cases, their quick response to customers needs, if the scope is too rigid with regard to the modification of test methods and the introduction of new ones using the same measurement principles. Document EA-2-05 published by the European Cooperation for Accreditation describes possibilities to allow flexibility in accredited laboratories. Several examples of a flexible scope are given.