Since the decadic attenuation coefficient μ 10 is related to the (Napierian) attenuation coefficient by μ μ 10 = μ μ ln ⁡ ⁡ 10 , we also have T = exp ⁡ ⁡ ( − − ∫ ∫ 0 ℓ ℓ ln ⁡ ⁡ ( 10 ) μ μ 10 ( z ) d z ) = 10 ∧ ∧ ( − − ∫ ∫ 0 ℓ ℓ μ μ 10 ( z ) d z ) .