1. If the average sound insulation of the objective volume is less than 30 decibels, but the normal conversation in the next room can be heard clearly and easy to understand the content of the conversation, then the sound insulation effect is very poor.
2. If you can hear a loud conversation at 30~35 decibels, you can hear quite clearly, and normal conversation can be heard, but it is not easy to understand, then the sound insulation effect is very poor.
3. Under 35~40 decibels, loud conversations can be heard, but not very clear. Normal conversations are also weak when heard, and the sound insulation effect is obviously average.
4. Under the condition of 40~45 decibels, loud conversations can be heard about, but not fully understood, normal conversations cannot be heard, and the sound insulation effect is better.
5. If you cannot hear a loud conversation at 45~50 decibels, but the loudest shouts and the loudest sound of the radio can only be heard slightly, then the sound insulation effect is good. Can score a 60 points.
6. If you can't hear the loudest yelling under 50~55 decibels, and the loudest sound cannot be heard when the radio is turned on, the sound insulation effect is considered excellent.