Comparing Noise Criterion (NC, NCB, RNC) to Noise Rating (NR) and dB(A).
dB(A) - LA - is a weighted method compensating for the human hearing of sound pressure at different frequencies.
Choosing appropriate noise criteria is important when specifying acceptable levels of noise. Most organizations use a particular index based upon practical experience. Recommended maximum noise levels for different types of rooms and standards are indicated in the table below
|Type of Room - Occupancy||Maximum Level (dB)|
- NC, NCB, RNC -
- NR -
|Very quiet||Concert and opera halls, recording studios, theaters, etc.||10 - 20||20||25 - 30||20|
|Private bedrooms, live theaters, television and radio studios, conference and lecture rooms, cathedrals and large churches, libraries, etc.||20 - 25||25||25 - 30||25|
|Private living rooms, board rooms, conference and lecture rooms, hotel bedrooms||30 - 40||30||30 - 35||30|
|Quiet||Public rooms in hotels, small offices classrooms, courtrooms||30 - 40||35||40 - 45||35|
|Moderate noisy||Drawing offices, toilets, bathrooms, reception areas, lobbies, corridors, department stores, etc.||35 - 45||40||45 - 55||40|
|Noisy||Kitchens in hospitals and hotels, laundry rooms, computer rooms, canteens, supermarkets, office landscape, etc.||40 - 50||45||45 - 55||45|