PART 1: FILTER ACCOMMODATIONIf recirculated air is used, the following requirements are met in ventilation assemblies in the main air ducts forrecirculated air:P P PRack space is available and rack location identified for future implementation of carbon filters orcombination particle/carbon filters.a.b. The mechanical system is sized to accommodate the additional filters.PART 2: PARTICLE FILTRATIONOne of the following requirements is met:P P Pa. MERV 13 (or higher) media filters are used in the ventilation system to filter outdoor air.1Project demonstrates that for 95% of all hours in a calendar year, ambient outdoor PM₁₀ and PM₂.₅levels measured within 1.6 km [1 mi] of the building are below the limits set in the WELL Air QualityStandards feature.b.PART 3: AIR FILTRATION MAINTENANCETo verify that the filtration system continues to operate as designed, projects must annually provide IWBI with:P P PRecords of air filtration maintenance, including evidence that filters have been properly maintainedas per the manufacturer's recommendations.a.WELL