Ringelmann scale

The Ringelmann scale (also called " Ringelmann Chart" or " Ringelmann Smoke Chart" ) is a scale for the opacity of smoke or dust. The Ringelmann scale was developed by Maximilian Ringelmann (1861-1931, as of 1888 professor of agricultural engineering at the French National Institute for Agricultural Research in Paris ( Institut National Agronomique ) and Head of the Station d' Essais de Machines ).

The dark areas were different from Ringelmann created as a black grid on white paper with defined surface portions black.

The Ringelmann scale has been introduced in various countries for testing / evaluation of combustion plants and is still in use today (eg in the BlmSchV ).