Strutt|Mechanical Services|Regenerated Noise|Attenuator (Empirical) inserts sound power levels into the active row of the worksheet.
The total sound power level is calulated using:
`L_(W,t otal) = 55log_10 V + 10log_10 N + 10log_10 H - 45`
Where:
`L_W` is the sound power level generated by the attenuator, dB re 10-12 W
`V` is the local velocity in the splitter airway, m/s
`N` is the number of airways
`H` is the airway height, mm
The following corrections are then applied to calculate octave band sound power levels:
| 63 Hz | 125 Hz | 250 Hz | 500 Hz | 1 kHz | 2 kHz | 4 kHz | 8 kHz |
| -4 | -4 | -6 | -8 | -13 | -18 | -23 | -28 |
References: