Noise monitoring

Constant monitoring of aircraft noise in the vicinity of the airport is a legal requirement. In particular, we are required to monitor the development of aircraft noise nuisance by performing long-term measurements and to check the effectiveness of the noise reduction measures that have been implemented.

Dresden International Airport's aircraft noise monitoring system consists of a central station in the administration building, five stationary monitoring points in the vicinity and a mobile monitoring point which can be used in different places selected in accordance with the requirements set by the Aircraft Noise Commission.

Steffen Mäder

Head of Noise/Environmental Protection


+49 (0)351 881-3020


+49 (0)351 881-3024

Noise monitoring points

Monitoring point 1: Water tower in Brunnenweg, Dresden-Hellerau
Monitoring point 2: Primary School 84, Heinrich-Tessenow-Weg, Dresden-Hellerau
Monitoring point 3: Private house, Medinger Strasse 12, Hermsdorf
Monitoring point 4: Private house, Grüne Aue 45, Dresden-Rähnitz
Monitoring point 5: Obstruction lights pylon on the airport grounds, Dresden-Weixdorf

Dresden Airport works closely with Cirrus Research plc. The British manufacturer of noise monitoring equipment, which has a branch office in Dresden, supplied the aircraft noise monitoring systems for the five stationary and two mobile monitoring points at Dresden Airport.

Cirrus Research plc

Click on the image to enlarge.

How noise is monitored

Measurements are taken and recorded continuously at all monitoring points at a frequency of one per second. Aircraft noise events are identified with the help of a graphical display of periodic measurements and aircraft noise identification parameters which can be configured to suit the location of the monitoring equipment and the acoustic conditions prevailing there (background noise, other noise sources). The parameters can also be used to filter out other noise sources such as vehicular traffic, birds or leaves.

The day's measurements and aircraft noise events are transmitted to the central data processing unit and matched to aircraft movements during the night, enabling each aircraft noise event to be related to a certain aircraft movement. This correlation process is performed with a time slot model. This enables the time the aircraft passes the monitoring point to be determined based on the actual aircraft take-off or landing times registered in the flight log, and taking the take-off and landing speeds of the various types of aircraft (jet aircraft, propeller aircraft, helicopters) into account. Noise events which meet the aircraft noise identification parameters and which were recorded near the theoretical passing time calculated can thus be matched automatically and precisely to a specific flight.

In order to avoid misinterpretation, meteorological data is collected simultaneously at two separate measuring points to check whether there were any extreme weather conditions prevailing at the time of the noise measurements, in particular wind speeds exceeding 8.3 m/s.  If there were, any aircraft noise events obtained in those conditions are automatically flagged and deleted from the statistics.

After manual assessment of the events and correlations, the final step is to calculate the key acoustic data such as the continuous sound pressure level according to DIN 45643.

Illustration: Noise monitoring point

Noise monitoring point

Illustration: Checking the measurements at a noise monitoring point

Checking the measurements at a noise monitoring point

Sound level reference values

Very faint noises in a range between 0 and 20 dB can actually only be measured in sound-proofed labs, because ordinary ambient noise will always exceed these levels. Even the "absolute silence" of the remotest place outdoors produces noise levels of between 20 and 30 dB. A standard A filter is installed in the monitoring equipment to make allowance for the varying sensitivity of human hearing to high and low sounds. The unit of measurement is thus referred to as dB(A).

The following rule of thumb is used to express the correlation between the measured sound pressure level and the distance to the source of the noise: Tripling the distance reduces the sound pressure level by 10 dB and thus halves the perceived noise nuisance.

Type of noise Sound pressure level
Hearing threshold  0 dB(A)
Breathing noise (at a distance of about 1 m)  25 dB(A)
Very quiet room  20-30 dB(A)
Ticking alarm clock  30-35 dB(A)
Rustling leaves  30-40 dB(A)
Whispering  40 dB(A)
Normal conversation (at a distance of about 1 m)  50-60 dB(A)
DA 20 Katana aircraft (2-seater, 0.7 t MTOW), passing at an altitude of 300 m  60 dB(A)
TV at room volume (at a distance of about 1 m)  55-60 dB(A)
Shouting  70 dB(A)
Car (at a distance of about 10 m)  60-80 dB(A)
ATR 42 aircraft (up to 50 seats, 16 t MTOW) during take-off, at a distance of about 300 m  75 dB(A)
AVRO RJ aircraft (up to 112 seats, 44 t MTOW) during take-off, at a distance of about 300 m  80 dB(A)
Main road (at a distance of about 10 m)  80-85 dB(A)
Airbus A320 aircraft (up to 180 seats, 74 t MTOW) during take-off, at a distance of about 300 m  85 dB(A)
Pneumatic drill at a distance of 1 m or heavy truck at a distance of 5 m  90 dB(A)
Boeing B747-400 aircraft (up to 524 seats, 386 t MTOW) during take-off, at a distance of about 300 m  90 dB(A)
Night club  110-120 dB(A)
Car horn at a distance of a few metres  110 dB(A)
Pain threshold  um 130 dB(A)

MTOW = Maximum Take-Off-Weight