What type of approval must a chemical have before being added to water?

The approval that a chemical must have before being added to water, especially in the context of drinking water treatment, is ANSI/NSF 60 approval. This certification signifies that the chemical meets specific safety and health requirements for use in drinking water treatment. ANSI/NSF 60 addresses the performance and health effects of chemicals used in water treatment processes, ensuring that any substance added does not adversely affect public health and complies with regulatory standards.

While other certifications like EPA certification address the broader regulatory aspects of chemical substances and their overall environmental impacts, ANSI/NSF 60 specifically targets the use of those chemicals in potable water systems, confirming their suitability for human consumption. This focus is crucial for water operators, as they must ensure the chemicals used do not introduce harmful contaminants into the water supply.

FDA approval typically relates to food safety and not specifically to the use of chemicals in water treatment, while ISO certification pertains more to organizational and manufacturing quality standards rather than chemical safety for water treatment applications.