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AHU Elements    1/1

Strutt|Mechanical Services|AHU Elements inserts approximate figures for the attenuation due to coils, filters, humidifiers, weather louvres and thermal wheels. These are a guide only and should be confirmed by manufacturer's data.

Heating and Cooling Coils
Selecting the appropriate number of rows of coils inputs the corresponding values into the active row of the worksheet:

 No. Rows 63 Hz 125 Hz 250 Hz 500 Hz 1 kHz 2 kHz 4 kHz 8 kHz 1 - 2 -1.0 -2.0 -2.0 -2.0 -2.0 -3.0 -3.0 -3.0 3 - 4 -2.0 -3.0 -3.0 -3.0 -3.0 -4.0 -4.0 -4.0 5 - 6 -3.0 -4.0 -4.0 -4.0 -4.0 -5.0 -5.0 -5.0 10 -6.0 -7.0 -7.0 -7.0 -7.0 -8.0 -8.0 -8.0

Bag Filter
Inputs the following values into the active row of the worksheet:

 63 Hz 125 Hz 250 Hz 500 Hz 1 kHz 2 kHz 4 kHz 8 kHz -2.0 -3.0 -5.0 -7.0 -8.0 -8.0 -8.0 -8.0

Humidifier
Inputs the following values into the active row of the worksheet:

 63 Hz 125 Hz 250 Hz 500 Hz 1 kHz 2 kHz 4 kHz 8 kHz -1.0 -3.0 -4.0 -5.0 -5.0 -5.0 -5.0 -5.0

Weather Louvre
Inputs the following values into the active row of the worksheet:

 63 Hz 125 Hz 250 Hz 500 Hz 1 kHz 2 kHz 4 kHz 8 kHz -2.0 -2.0 -2.0 -2.0 -3.0 -3.0 -3.0 -3.0

Thermal Wheel
Inputs the following values into the active row of the worksheet:

 63 Hz 125 Hz 250 Hz 500 Hz 1 kHz 2 kHz 4 kHz 8 kHz -2.0 -3.0 -3.0 -3.0 -3.0 -4.0 -4.0 -4.0

Roll Filter
Inputs the following values into the active row of the worksheet:

 63 Hz 125 Hz 250 Hz 500 Hz 1 kHz 2 kHz 4 kHz 8 kHz -3.0 -4.0 -5.0 -6.0 -8.0 -8.0 -8.0 -8.0

References:

• Arup, Sound and Vibration in Mechanical Services Design, Table 18