ASHRAE 52.2-2025 ✓ Most Recent

ANSI/ASHRAE Standard 52.2 establishes a method of laboratory testing to measure the performance of general ventilation air-cleaning devices in removing particles of specific diameters.

The 2024 edition adds a new PM(X)52.2 particle removal efficiency for the indoor environment based three sizes of particles with an optical diameter between 0.3 and 10 μm. The calculated efficiency, based on the E1 (0.3–1.0), E2 (1.0–3.0), and E3 (3.0–10.0) ranges, is PM1_52.2, PM2.5_52.2, and PM10_52.2. The PM “52.2” designation is not the same as the EPA PM mainly due to different size cut off ranges and different particle measurement methods. Although not exactly equivalent to the EPA PM size designation, PM 52.2 will give reasonable approximation.

The 2024 edition also adds an optional method for bioaerosol testing of devices other than UV using a Standard 52.2 duct with aerosolized microorganisms, and makes numerous changes to terminology to significantly improve clarity and use.