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40 CFR Part 53, Table F-2 — Particle Sizes and Wind Speeds for Full Wind Tunnel Test, Wind Tunnel Inlet Aspiration Test, and Static Chamber Test

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov
Primary Partical Mean Size a (µm)Full Wind Tunnel TestInlet Aspiration TestStatic Fractionator TestVolatility Test
2 km/hr24 km/hr2 km/hr24 km/hr
1.5±0.25SS|S |
2.0±0.25SS|S |
2.2±0.25SS|S |
2.5±0.25SS|S |
2.8±0.25SS|S |
3.0±0.25|LL |
3.5±0.25SS|S |
4.0±0.5SS|S |
Polydisperse Glycerol Aerosol|| L

a Aerodynamic diameter.

S = Solid particles.

L = Liquid particles.