The concepts described on these pages are words and expressions used in statistics with a specific, limited meaning. In everyday speech the word may have a different meaning. In connection with each definition you can find information about which sets of statistics use the concept.

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A mixture of a liquid and a high percentage of finely powdered solid substance. In waste statistics the liquid of the mixture is included in the amount of waste, but not in the case of a sludge in which the liquid content is high compared to the solid matter.

Only the dry matter contained in the sludge from waste water treatment plants is regarded as waste in statistics.

Statistics using the definition

Validity of the definition

  • Valid until (31 December 2078)

Source organisation

  • EU

Related concepts