What testing method is used to best determine filter efficiency?

The independent laboratory ANSI/ASHRAE 52.2 test is recognized as a standard method for determining filter efficiency. This method provides a comprehensive and reliable assessment of how effectively a filter captures particulate matter from the air. The ANSI/ASHRAE 52.2 testing protocol involves precise measurements and controls that are accepted across the industry, ensuring that results are consistent and comparable among different products.

This testing method is crucial because it uses a rigorous approach to quantify the filter's performance in capturing various particle sizes, which helps manufacturers and customers understand the overall efficacy of the filter. The results generated from this standardized testing are also useful for regulatory compliance and fulfilling certification requirements.

Other methods, like field tests with customer input or visual inspections, lack the systematic rigor and reliability of certified laboratory testing. Homemade testing equipment would not meet the necessary standards for accuracy and repeatability, making it unsuitable for determining filter efficiency. Therefore, using an independent laboratory that adheres to ANSI/ASHRAE 52.2 testing ensures that the evaluation of filter performance is both trustworthy and scientifically valid.