TC is a single number rating that indicates the sound transmission loss over a defined range of frequencies of a door assembly between adjacent closed rooms. Higher values equate to better sound reduction performance.
Decibels dB, are used to express the intensity of a sound wave. Examples of decibels levels are:
- 100-120 Deafening industrial machinery, jet engines
- 80-100 Very loud cocktail party, boom box
- 60-80 Quiet speech
- 20-40 Faint soft whisper, recording studio
- 0-20 Very faint acoustical laboratories, deep caves