Performance characteristics of underlays

There are a number of performance characteristics for underlays under MMF flooring in relation to specific requirements:

1. Performance in relation to the substrate/construction

PC: punctual conformability
SD: water vapor diffusion resistance
R:  thermal resistance

2. Performance in relation to the use of the floor covering
DL:
dynamic load
CS and CC: compressive strength and compressive creep

3. Performance based on acoustics
IS: 
impact sound reduction