Silence Fan Analysis Report
What does absolute silence sound like?
Proof of the dB Values
A ceiling fan should be seen but not heard. Whether in the bedroom for a restful sleep or in the office for focused work – noise level is a crucial quality feature. We had our AE and FR series models thoroughly tested at the renowned Indoor Environmental Quality Laboratory of the University of Sydney. Learn here why Aeratron fans are among the quietest in the world and how we scientifically measure "silence."
Summary
The goal was to examine the acoustic profile of the 9 different Aeratron ceiling fans (FR3, AE+2, and AE+3 series). The measurements were conducted in the Indoor Environmental Quality (IEQ) laboratory at the University of Sydney. Sound pressure level measurements were taken at a height of 1.2 meters above the floor (head height of a seated person) directly under the fan (0 m) as well as at distances of 1 meter (1 m) and 2 meters (2 m) from the center in a sparsely furnished office environment in Chamber 1 of the IEQ lab. Measures were taken to seal the windows and doors with additional insulation material to minimize noise intrusion.
Methodology
The low-noise microphone system Bruel & Kjaer Type 4179 was connected to an impulse front-end data acquisition module of type 3560. The hardware was controlled by a computer running the Bruel & Kjaer Pulse software (version 20).
The system’s noise floor was determined by the microphone, which in this case has a very low self-noise level of -2.5 dB(A) over a frequency range of 20 Hz to 20 kHz. This ensured that the sound measurements were below the hearing threshold.
The microphone was calibrated before the measurement using a Bruel & Kjaer sound calibrator of type 4231 (serial number 3007062). The calibrator has a current NATA certification (calibration number CAU 1901034), valid until 21.10.2020.
The noise measurements lasted at least 60 seconds, with additional time allowed if the measurements were affected by a temporary increase in background noise level, for example from passing motorcycles or heavy vehicles.
The measurements were analyzed using a moving time window of 10 seconds. The equivalent A-weighted sound pressure level (dB LAeq re 2 x 10-5 Pa) was calculated for each time window. The results show the minimum recorded value for a 10-second window.