Noise Criterion vs. Noise Rating and dB(A)

Comparing Noise Criterion (NC, NCB, RNC) to Noise Rating (NR) and dB(A). Determines appropriate noise criteria for different room types and occupancy levels.

Noise Criterion vs. Noise Rating and dB(A)

Noise Criterion - NC - were established in U.S. for rating indoor noise, noise from air-conditioning equipment etc.

In Europe it is common to use Noise Rating Curves - NR.

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.

Room Type & Occupancy	NC/NCB/RNC (dB)	NR (dB)	dB(A)	RC
Very quiet - Concert and opera halls, recording studios, theaters	10-20	20	25-30	20
Private bedrooms, theaters, TV/radio studios, conference rooms, libraries	20-25	25	25-30	25
Private living rooms, board rooms, hotel bedrooms	30-40	30	30-35	30
Quiet - Public rooms in hotels, offices, classrooms, courtrooms	30-40	35	40-45	35
Moderate noisy - Drawing offices, bathrooms, reception areas, lobbies, stores	35-45	40	45-55	40
Noisy - Kitchens, laundry rooms, computer rooms, supermarkets	40-50	45	45-55	45

Calculator

Inputs

Room Type & Occupancy

Results

Noise Criterion NC/NCB/RNC Range-- dB

Noise Rating (NR) Level-- dB

dB(A) Range-- dB

RC Level-- dB