ABSTRACT

This study presents the heavy metal results obtained during Finnish interlaboratory comparison (ILC) measurements made during 2019. The aim of this measurement campaign was to verify the skills of accredited emission measurement teams and also to evaluate the challenges that stack testing teams face in the future when emission levels decrease. ILCs have been organized in Finland since the 1970s. ILCs provide an important platform for stack testing teams so that they can verify their measurement skills and also for the dissemination of knowledge. The knowledge about the measurement standards and their requirements has improved among stack testing teams during past years in Finland. As emission levels get lower, they still need to pay more attention to some quality assurance procedures, e.g. to method and field blanks. Based on the observations of this ILC for heavy metals it can be noted that the challenges that stack testing teams face are related to the fact that no guidance is given in the standard reference methods EN 13211 and EN 14385 for example on the calculation of measurement uncertainties and how results below limit of quantification should be taken into account. These reference methods were suitable for their purpose at the time they were validated. However, emission levels are now more stringent and it is challenging to measure them with acceptable uncertainty criteria. As a consequence, there is a clear need for harmonized approaches in Europe for consistent implementation of standards and regulations. Key issues where guidance should be provided include realistic measurement uncertainties at low concentration levels, reporting low concentrations and guidance on how measurement uncertainties should be taken into account when the results are used for compliance assessment. The overall aim is to ensure that even with low emission levels, the emission measurement results would be transparent and robust throughout the EU.

Implications: Interlaboratory comparison measurements between stack testing teams are the most important tool to verify the quality of the measurements. Participation in an appropriate ILC is often mandatory to successfully achieve accreditation under ISO/IEC 17025. Such campaigns also provide an efficient platform for dissemination of knowledge. In addition, ILCs can be used to clarify the challenges that teams nowadays face when measuring low emission levels, thus creating important information for the revision work of standards.

摘要

这项研究提出了在2019年进行的芬兰实验室间比较（ILC）测量中获得的重金属结果。此测量活动的目的是验证经过认证的排放测量团队的技能，并评估烟囱测试团队未来面临的挑战当排放水平降低时。自1970年代以来，ILC在芬兰已组织起来。ILC为堆栈测试团队提供了一个重要平台，以便他们可以验证其测量技能并传播知识。在过去的几年中，芬兰的堆栈测试团队对测量标准及其要求的了解有所提高。随着排放水平降低，他们仍然需要更加注意一些质量保证程序，例如方法和现场空白。根据该重金属ILC的观察结果，可以注意到堆垛测试团队面临的挑战与以下事实有关：标准参考方法EN 13211和EN 14385中未提供指导，例如测量不确定度的计算以及如何考虑低于定量限的结果。这些参考方法在经过验证时适合其目的。但是，现在的排放水平更加严格，以可接受的不确定性标准对其进行测量具有挑战性。结果，在欧洲显然需要采用统一的方法来一致地执行标准和法规。应提供指导的关键问题包括低浓度水平下的实际测量不确定度，报告低浓度，以及在将结果用于合规性评估时应如何考虑测量不确定性的指南。总体目标是确保即使在低排放水平下，整个欧盟的排放测量结果也将是透明且可靠的。

含义：堆栈测试团队之间的实验室间比较测量是验证测量质量的最重要工具。要成功获得ISO / IEC 17025的认证，通常必须参加适当的ILC。此类活动也为传播知识提供了有效的平台。此外，ILC可用于阐明当今团队在测量低排放水平时面临的挑战，从而为标准的修订工作提供重要信息。