Refers to the thickness of the current floor.
Refers to the density of the current floor layer, ie how heavy it is.
The loss factor describes the relatively lost energy per radius.
The frequency is the periodic velocity of a sound wave, i.e. the number of oscillations per second the sound wave does. Frequency is measured in Hertz (Hz) which is a unit derived from the SI system and corresponds to 1 oscillation per second.
At what frequency the building component in question creates resonance.
The reduction number is defined as a relationship between incident sound effect on one side of a wall and transmitted sound effect to the other side of the same wall.