EBAS is a database hosting observation data of atmospheric chemical composition and physical properties. EBAS hosts data submitted by data originators in support of a number of national and international programs ranging from monitoring activities to research projects, and is developed and operated by the Norwegian Institute for Air Research (NILU).

The NILU framework contains data from the Norwegian Background Air and Precipitation Monitoring Programme, which has run various projects including measuring and monitoring air quality since the 1970s. More information is available at their website, http://www.nilu.no. NILU administers the EBAS database and provides quality assurance for its data.

This record refers to data downloaded under the NILU framework for components pm10_mass, pm25_mass, and pm10_pm25_mass.