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ScriptableRenderPipeline/HDRenderPipeline/HDRP/Lighting/Volumetrics/VolumetricLighting.cs

 public struct DensityVolumeParameters
 {
     public Color albedo;       // Single scattering albedo: [0, 1]. Alpha is ignored
-    public float meanFreePath; // In meters: [1, FLT_MAX]. Should be chromatic - this is an optimization!
+    public float meanFreePath; // In meters: [1, 1000000]. Should be chromatic - this is an optimization!
     public float asymmetry;    // Controls the phase function: [-1, 1]
 
     public void Constrain()