Range of sound levels |
Range of NC curves | |||
dB A | NC | |||
Large buildings |
Radio and TV studios........................................ | 25-30 | 20-25 | |
Concert and opera halls..................................... | 25-35 | 20-30 | ||
Churches........................................................ | 25-35 | 20-30 | ||
Theaters, Multipurpose halls............................... | 25-35 | 20-30 | ||
Libraries, Museums........................................... | 25-35 | 20-30 | ||
Schools, Classrooms......................................... | 30-40 | 25-35 | ||
Cinema........................................................... | 35-45 | 30-40 | ||
Banquet halls................................................... | 40-50 | 35-45 | ||
Hospitals |
Private rooms.................................................. | 30-40 | 25-35 | |
Operation Theaters........................................... | 35-45 | 30-40 | ||
Halls, Laboratories............................................ | 35-45 | 30-40 | ||
Waiting rooms................................................. | 40-50 | 35-45 | ||
Offices |
Board rooms.................................................... | 25-35 | 20-30 | |
Conference rooms............................................ | 30-40 | 25-35 | ||
Executive Offices............................................. | 35-45 | 30-40 | ||
General open offices......................................... | 35-45 | 30-40 | ||
Typing pools................................................... | 40-50 | 35-45 | ||
Computer rooms............................................... | 45-65 | 40-55 | ||
Hotels, Restaurants |
Rooms............................................................ | 30-40 | 25-35 | |
and stores |
Restaurants.................................................... | 35-45 | 30-40 | |
Halls, Lobbies.................................................. | 35-45 | 30-40 | ||
Stores........................................................... | 40-50 | 35-45 | ||
Supermarkets.................................................. | 45-55 | 40-50 | ||
Residential |
Single Family homes (rural and suburban).............. | 25-35 | 20-30 | |
Buildings |
Single Family homes (urban)............................... | 30-40 | 25-35 | |
Apartment buildings.......................................... | 35-45 | 30-40 | ||
Factories |
Light machinery, assembly lines........................... | 50-70 | 45-65 | |
foundries, heavy machinery................................ | 60-80 | 55-75 | ||
Damage risk criteria |
90 | 85 |