Engineers are under increasing pressure to meet ASHRAE ventilation requirements while also achieving ambitious goals around energy efficiency, sustainability, occupant health, infrastructure utilization, and project budgets. Too often, these objectives compete with one another.

While IAQP has long been part of ASHRAE 62.1, adoption remains limited due to the complexity of contaminant modeling, performance verification, and compliance documentation. ASHRAE 62.1-2022 addressed these barriers with a more structured framework for contaminant assessment, verification, and ongoing monitoring, making IAQP a more practical and reliable pathway to compliance.

Using mass-balance calculations, IAQP evaluates how outdoor air and cleaned recirculated air work together to keep contaminant concentrations below established limits. If the calculations demonstrate compliance, outdoor air requirements can be reduced while maintaining acceptable indoor air quality.

This is not a shortcut or a loophole. It's a documented engineering approach based on measured performance and verified results. For each design compound identified within ASHRAE 62.1, engineers evaluate contaminant removal, calculate resulting concentrations, and document compliance. The contribution of the air cleaning system is based on validated removal efficiencies, not manufacturer claims alone. That's why ASHRAE requires air cleaners used in IAQP applications to be tested to recognized standards, providing performance data that can be incorporated into the compliance calculations.