DIN 51813
DIN 51813 Testing of lubricants - Determination of the content of foreign solid matters in lubricating greases - Particle sizes above 25 µm
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 03/01/2016
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 03/01/2016