The EQAT scheme has its origin in the quality management activities of the biology workgroup of the Arbeitsgemeinschaft Trinkwassertalsperren (ATT e.V.) in the 1990s. Since 2002, the proficiency test phytoplankton has been carried out on an international level by the LTV.
The results from 65 participants have now been summarised in preliminary figures and tables.
The preliminary analysis confirmed the stability of the natural phytoplankton sample. Neither during the analysis period nor during transport changed the cell and biovolume concentration of the five algentaxa. Moreover, all values were between zu-scores of -2 and +2 of the preliminary results.
Please now verify your submitted data in the context of the overall EQAT results. If there are obvious errors/discrepancies, please contact us. At this stage, no changes can be made to the result values themselves. Rather, the aim is to ensure that we have correctly allocated the data and results.
You can report issues until April 10th, as we will start producing the certificates at the end of April. These will be sent individually by e-mail.
Inter-laboratory comparisons are an essential part of external quality assurance. Laboratories can test and improve their analytical performance. The EU Water Framework Directive sets high standards for the quality of phytoplankton analysis and requires regular participation in proficiency testing. EQAT Phytoplankton organises such ring trials every 2 years, with typically between 60 and 70 participants. The German Accreditation Body, DAkkS (www.dakks.de), accredits EQAT Phytoplankton for phytoplankton analysis according to DIN EN ISO 17025:2018 and as a provider of interlaboratory comparisons according to DIN EN ISO/IEC 17043:2010. With the help of the innovative reference counting chamber developed by EQAT Phytoplankton, systematic errors can be clearly distinguished from errors related to the detection of algae. This is done within the established work processes at the inverted microscope (Utermöhl technique).
The proficiency tests are based on the procedures described in the DIN EN 15204:2006 Guidance standard on the enumeration of phytoplankton using inverted microscopy (Utermöhl technique) and in DIN EN 16695:2015 Water quality - Guidance on the estimation of phytoplankton biovolume.
