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We aim to use iSPEX for the biggest citizen science project ever in the Netherlands. We hope to do so by distributing about 10,000 iSPEX add-ons among enthousiast iSPEX users across the Netherlands. The use of the free app will allow every iSPEX user to do aerosol measurements.

With iSPEX we want to increase knowledge about aerosols among:

  • the general public, by their participation in actual aerosol research,
  • the scientific community, by providing them with an additional source of information which hopefully creates new starting points for follow up research.

On a sunny day in May or June 2013, we will organize a National iSPEX-measurement campaign, on which we ask all iSPEX users to perform measurements. These measurements will be combined with measurements from professional instrumentation (among which the SPEX instrument at Cabauw, which is developed within our team) and with measurements of an iSPEX on a weather balloon. The data will be processed into an aerosol map of the Netherlands. If this yields succesful results, more campaigns can be organized, perhaps when different circumstances occur, such as volcanic eruptions or the passing of Sahara dust. Taking iSPEX to other European countries will certainly be explored.

Note this…

  • The iSPEX project is an experiment. Results are not guaranteed.
  • The goal of the iSPEX project is to measure the density of  fine dust, its particle size distribution, and a rough indication of the composition of fine dust based on the determination of the complex refractive index. The latter quantities are important for health studies on fine dust .
  • The results of iSPEX measurements do not provide quantities for which official or legal standards are applicable.
  • Results of iSPEX measurements cannot be directly compared with PM10 or PM2,5 measurements; they are of a different nature. A direct comparison with limit values for fine dust (in ug/m3) is  therefore not possible. See  lml.rivm.nl for PM10 or PM2,5 values.
  • With iSPEX you measure not only the fine dust in the close vicinity near the ground, but also further away, in the higher parts of the atmosphere. Whether  iSPEX measurements are relevant for the air you breath can only be determined with the help of additional measurements and/or model calculations.
  • iSPEX only works properly for a cloudless blue sky.
  • An individual iSPEX measurement gives-directly when using the App- only a qualitative  indication of the sky brightness at a low accuracy.
  • The indication of the presence of fine dust given in the App is related to the optical thickness of the dust. This is complex information and a proper interpretation requires specialist knowledge.
  • Individual iSPEX measurements have to be averaged over approximately 100 measurements to obtain reliable values.
  • Initially the iSPEX project will focus only on the analysis of the data obtained during the Dutch national iSPEX measurement day.
  • The analyses of the iSPEX data and the determinations of the quantities mentioned above are done centrally by the iSPEX team and will only be made available through or with explicit permission of the RIVM and the KNMI.
  • The data obtained during the iSPEX project will be used for scientific research. Scientific results will be anonimized before analysis and publication.