RC - the Room Criteria
Room Criteria (RC) measures the background noise in buildings over frequencies ranging 16 Hz to 4000 Hz.
RC requires a determination of the mid-frequency average level and the perceived balance between high and low frequency sound.
| Type of Room - Space Type | Recommended RC Level RC Curve | Equivalent Sound Level dB(A) |
|---|---|---|
| Apartments | 25 - 35 (N)1) | 35 - 45 |
| Assembly Halls | 25 - 30 (N) | 35 - 40 |
| Churches | 30 - 35 (N) | 40 - 45 |
| Courtrooms | 30 - 40 (N) | 40 - 50 |
| Factories | 40 - 65 (N) | 50 - 75 |
| Hotels/Motels | ||
| - Individual rooms or suites | 30 - 35 (N) | 35 - 45 |
| - Meeting or banquet rooms | 25 - 35 (N) | 35 - 45 |
| - Service and Support Areas | 40 - 45 (N) | 45 - 50 |
| - Halls, corridors, lobbies | 35 - 40 (N) | 50 - 55 |
| Offices | ||
| - Conference rooms | 25 - 30 (N) | 35 - 40 |
| - Private | 30 - 35 (N) | 40 - 45 |
| - Open-plan areas | 35 - 40 (N) | 45 - 50 |
| - Business machines/computers | 40 - 45 (N) | 50 - 55 |
| Hospitals and Clinics | ||
| - Private rooms | 25 - 30 (N) | 35 - 40 |
| - Operating rooms | 25 - 30 (N) | 35 - 40 |
| - Wards | 30 - 35 (N) | 40 - 45 |
| - Laboratories | 35 - 40 (N) | 45 - 50 |
| - Corridors | 30 - 35 (N) | 40 - 45 |
| - Public areas | 35 - 40 (N) | 45 - 50 |
| Schools | ||
| - Lecture and classrooms | 25 - 30 (N) | 35 - 40 |
| - Open-plan classrooms | 30 - 40 (N) | 45 - 50 |
| Movie motion picture theaters | 30 - 35 (N) | 40 - 45 |
| Libraries | 35 - 40 (N) | 40 - 50 |
| Legitimate theaters | 20 - 25 (N) | 30 - 65 |
| Private Residences | 25 - 35 (N) | 35 - 45 |
| Restaurants | 40 - 45 (N) | 50 - 55 |
| TV Broadcast studies | 15 - 25 (N) | 25 - 35 |
| Recording Studios | 15 - 20 (N) | 25 - 30 |
| Concert and recital halls | 15 - 20 (N) | 25 - 30 |
| Sport Coliseums | 45 - 55 (N) | 55 - 65 |
| Recording studios | 15 - 20 (N) | 25 - 30 |
1) Neutral (N). The levels in the octave bands centered at 500 Hz and below must not exceed the octave-band levels of the reference spectrum by more than 5 dB at any point in the range; the levels in the octave bands centered at 1000 Hz and above must not exceed the octave-band level of the reference spectrum by more than 3 dB at any point in the range.
Related Topics
• Acoustics
Room acoustics and acoustic properties, decibel A, B and C, Noise Rating (NR) curves, sound transmission, sound pressure, sound intensity and sound attenuation.
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