USA EPA Method 2G Overview: Stack Flow Rate & 2D Probe Velocity Explained

In this comprehensive overview, we break down USA EPA Method 2G, the federal standard for determining stack gas velocity and volumetric flow rate using two-dimensional (2-D) directional probes. When stack gas flow exhibits cyclonic or swirling patterns, a standard Method 2 pitot tube overestimates flow. Method 2G solves this by isolating the yaw angle to find the true axial velocity!

🔍 What is EPA Method 2G?
EPA Method 2G is used to account for angular (non-axial) flow in smokestacks and ducts. By measuring the yaw angle—the horizontal deviation of the gas velocity vector from the stack axis—this method allows field technicians to apply a correction factor, ensuring highly accurate volumetric flow rate reporting for emissions compliance. If this technical overview helped clarify Method 2G for you, please hit the Like button and Subscribe for more deep dives into EPA stationary source testing methods! #EPAMethod2G #StackTesting #2DProbe #YawAngle #EnvironmentalEngineering #AirQuality #EmissionsCompliance #FlowRate