The aims of this protocol are to establish a common agreement between EUMETSAT, NILU and relevant data partners in context of the ETALON-NADIR service, to encourage dissemination of data and results for scientists involved in Research Infrastructures (RI)s, Fiducial Reference Measurements (FRM)s, measurement campaigns and contributing networks/stations, and to protect the rights of the individual scientists involved in these. Several types of sources are contributing to the NADIR database: field measurement campaigns, monitoring networks, and measurements from individual scientists. Campaign data sets are data organized, produced or led within field measurement. Network data are data archived by and from infrastructures, frameworks and organizations e.g.: NDACC (http://www.ndsc.ncep.noaa.gov/), SHADOZ (https://tropo.gsfc.nasa.gov/shadoz/) or PGN (https://www.pandonia-global-network.org/). Data are either stored in NADIR, or brokered from the primary source.The data are provided to NADIR with the permission of each organization or data provider.

1. Preliminary data should be replaced as soon as possible by consolidated final data in the NADIR database. The descriptive information in the data file and associated metadata shall reflect such an update.
2. NADIR primarily follows the GEOMS and CF metadata guidelines. Data submitted to the database should thus be preferably GEOMS compliant, following the templates available from the data center, or CF compliant. If a GEOMS template is not available: individual procedures may apply. Please contact the data centre for more information.
3. The ownership of the data remains with the data originator.
4. Data remains protected by their individual and primary license, neither NADIR nor EUMETSAT can share the data with 3rd parties in case of restricted licenses and ownership rights.
5. Users belonging to a specific network or campaign can share and access all the data within this network or campaign, but the other users will have, generally, no access to these data. Re-distribution of restricted data to third parties is nominally not allowed and requires written permission from the funding body and the data originator.
6. Any publication resulting from use of NADIR data requires prior written permission from the data owner. The data user accepts that an offer for co-authorship will be made through personal contact with the data providers or owners whenever substantial use is made of their data. In the case of network data it is also necessary to reproduce the acknowledgements as formulated in the respective network data policy.
7. Access to the data hosted in NADIR is granted only after having signed this protocol. Access is strictly personal through nominative login and password. All data reported as preliminary or final, are available to those with access to the NADIR at no cost for non-commercial scientific use.