GAC tests are used to determine the effectiveness of your granular activated carbon (GAC) filter. GAC filters are proven to be effective at removing many types of chemicals from water. They are also used to remove chemicals that cause unpleasant tastes or odors such as hydrogen sulfide and chlorine. However, your filter may lose its effectiveness over time or there may be other circumstances causing it to be ineffective such as damage to the filter. It is important to regularly test your water to ensure that your filter is doing its job.

It is recommended that you have a GAC test completed at least once a year. You must test both untreated and treated water to determine the filter’s effectiveness. If contaminant levels are high, you will want to test your water more frequently. The appropriate level of contaminants in your water will be determined by the EPA, state, and local regulatory bodies.