The sound emission of the projected Aerzen machines, the connected piping systems and the sound propagation in the room resp. free field is examined and described including:

• Compilation of existing acoustic-related data
• Calculation of radiating noise according to VDI 3733
• Determination of room influence and, if so, other background noises
• Determination of the expected room level
• Recommendation of measures to achieve the guaranteed values for room or immission.

Verification of the guaranteed value by acoustic evaluations and interpretation, partly by complex sound intensity measuring according to ISO 9614.

Sound optimization for existing plants

• Recording of acoustic data and conditions at site
• Comparison of measured data with the disturbance variables to be calculated (frequency position, resonant frequencies)
• Discussion on result and proposal for optimization with quotation

Verification of the guaranteed value by acoustic evaluations and interpretation, partly by complex sound intensity measuring according to ISO 9614.

Sound measuring

Sound measuring is done by means of the sound level meter type 2238 Mediator ( Brüel & Kjaer) with ½” microphone.

This instrument meets the following standards:

• IEC 651 – 1979 type 1l
• EN 60651 type 1l
• IEC 804 – 1985 type 1
• EN 60804 type 1l
• Draft IEC 1672 / EN 61672 – April 1997
• ANSI S1.43 – 1983 type S1

The software NOISE EXPLORER type 7815 (Brüel & Kjaer) was used for measuring and evaluation.

Measuring was recorded as TERZ analysis (23% - band filter).

Sound measuring / Sound intensity measuring according to DIN EN ISO 9614 Part 1,2

This standard comprises two parts for the measuring methods:
Part 1: Measuring at discrete points and
Part 2: Measuring by scanning

DIN ISO 9614 Part 2
Class 2 and 3 of accuracy can be achieved by using the scanning method. Based on this classification upper uncertainty limits of measured sound power level can be guaranteed

Sound intensity measuring is performed using the following measuring instruments: