OB-RL Office Building and Research Laboratory District
Octave Band Center Frequency (hertz) | Sound-Pressure Level* (decibels) |
|---|---|
31.5 | 67 |
63 | 62 |
125 | 52 |
250 | 46 |
500 | 40 |
1,000 | 36 |
2,000 | 33 |
4,000 | 30 |
8,000 | 27 |
*According to the following formula: Sound-pressure level, in decibels, equals 20 LOG P/P2, where P2 equals 0.0002 dyne per square centimeter. |
Type of Operation or Character of Noise | Correction in Decibels |
|---|---|
Daytime operation only | Plus 5 |
Noise source operates less than 20% of the time | Plus 5* |
Noise source operates less than 5% of the time | Plus 10* |
Noise source operates less than 1% of the time | Plus 15* |
Noise of impulsive character (hammering, etc.) | Minus 5 |
Noise of periodic character (hum, screech, etc.) | Minus 5 |
*Apply one of these corrections only. |
OB-RL Office Building and Research Laboratory District
Octave Band Center Frequency (hertz) | Sound-Pressure Level* (decibels) |
|---|---|
31.5 | 67 |
63 | 62 |
125 | 52 |
250 | 46 |
500 | 40 |
1,000 | 36 |
2,000 | 33 |
4,000 | 30 |
8,000 | 27 |
*According to the following formula: Sound-pressure level, in decibels, equals 20 LOG P/P2, where P2 equals 0.0002 dyne per square centimeter. |
Type of Operation or Character of Noise | Correction in Decibels |
|---|---|
Daytime operation only | Plus 5 |
Noise source operates less than 20% of the time | Plus 5* |
Noise source operates less than 5% of the time | Plus 10* |
Noise source operates less than 1% of the time | Plus 15* |
Noise of impulsive character (hammering, etc.) | Minus 5 |
Noise of periodic character (hum, screech, etc.) | Minus 5 |
*Apply one of these corrections only. |