Used in environmental and water quality testing to calibrate instruments for measuring nitrite levels in drinking water, wastewater, and natural water bodies. Essential in agricultural labs to monitor nitrite concentrations in soil and irrigation water, helping manage fertilizer use and prevent contamination. Commonly used in food and beverage industries to ensure safety and compliance by controlling nitrite levels in cured meats and processed foods. Also employed in research and clinical laboratories for analytical procedures involving nitrogen cycle studies and metabolic assays.