Term: power level
https://doi.org/10.1351/goldbook.P04793

Definition:
Logarithm of the ratio of a power to a reference power. Levels are expressed in different ways: LP = (1/2).ln(P/P0).Np, where Np is the symbol for the unit neper coherent with the SI, or LP = 10.log10(P/P0).dB, where dB is the symbol for the unit decibel.

Related Terms:
1) power (http://doi.org/10.1351/goldbook.P04792).
2) neper (http://doi.org/10.1351/goldbook.N04106).
3) decibel (http://doi.org/10.1351/goldbook.D01546).

Source: Green Book, 2nd ed., p. 79 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Citation: 'power level' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04793

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