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These sources have an omni-directional directivity across the entire surface of the source. Their unit is dB(A)/m² (or dB/m² at the input of the spectrum). We're talking about "ground" power, so power per square meter of a horizontal surface. In case of multi-level source, power is distributed on each source height.

The number of sources on a single horizontal surface is limited to 500.

The spectrum (in m²) is distributed over each source based on the surface area and the number of vertical source. For a source, we have:

 num sources = num horizontal sources x num height sources

 Spectrum(Point source) = Spectrum(from User) +  10 x log10(polygon area) - 10 x log10(num sources)

Note: no source is created inside building.