Used primarily in water and wastewater analysis to determine color intensity. The solution serves as a reference standard in visual and instrumental color comparison methods. It is essential in industries such as pharmaceuticals, food and beverage, and environmental monitoring where precise color measurement ensures product quality and regulatory compliance. Commonly used in conjunction with the Platinum-Cobalt (Pt-Co) scale, also known as the Hazen scale, to match or calibrate instruments like colorimeters and spectrophotometers. Provides consistent and reproducible results for detecting trace discoloration in clear liquids.