Used in environmental and industrial laboratories to calibrate instruments for measuring sulfite levels in water and wastewater. Commonly applied in the food and beverage industry to monitor sulfite concentrations in products like wine and dried fruits, where sulfites act as preservatives. Also utilized in boiler water treatment to ensure proper dechlorination and prevent corrosion by maintaining accurate sulfite residual levels. Supports quality control in pharmaceutical manufacturing where sulfite content must be tightly regulated.