Used as a reference standard in environmental testing laboratories to calibrate instruments and validate analytical methods for the determination of nitrite nitrogen in water samples. Ensures accuracy and reliability in monitoring nitrite levels in drinking water, wastewater, and surface water. Helps maintain compliance with regulatory standards by providing a known concentration for quality control and assurance programs. Commonly used in spectrophotometric, colorimetric, and ion chromatography analyses. Supports consistent measurement across different testing batches and laboratories.