Used in calibration of analytical instruments such as atomic absorption spectrophotometers and inductively coupled plasma (ICP) systems for accurate detection and quantification of cadmium in environmental, industrial, and biological samples. Commonly applied in water quality testing to monitor cadmium contamination in drinking water, wastewater, and natural water sources. Supports compliance with regulatory standards in environmental protection and occupational health. Also used in research and quality control laboratories for method validation and routine analysis of cadmium levels in soil, food, and consumer products.