The methods in measuring the density of smoke in brief are:
- With eyesight
To measure the density of smoke in accordance with uniformed diagram.
To measure the alteration of ray from source of light through the gas exhausted.
- Physical way
To weight the solid substances in a certain volume of exhausted gas. And in the medium or smaller
plants, measurement of the density of smoke relies upon the Ringelman way, which is the standard in
regulating the smoke in many of the countries.