A University of Waterloo Professor has received funding to conduct research into Infra Sound.
Associate Professor Richard Mann's study, "Measurement, Analysis and Synthesis of Infra Sound," will measure the effect of Low Frequency Noise and Infra Sound.
Mann says he will study not only wind turbines, but other man made and natural sources of the noise.
He says while both are known it impact human health, there are no standards for infra sound exposure.
He says low frequency noise and infra sound are largely unstudied.
He says infra sound comes from many sources, including waves, thunder, heating systems, industrial machinery, moving vehicles, and wind turbines.
He plans to reproduce the complete sound, audible , and infra sound, under controlled lab conditions.
He has put together a measurement system of infra sound microphones, a micro barometer and a silicon pressure sensor.
Mann says, "I have constructed a measurement system consisting of G.R.A.S. 40AZ infra sound microphones (0.5 to 20000 Hz), an Infiltec INFRA20 micro barometer (0.05 to 20 Hz) and a Honeywell silicon pressure sensor (0-15 psi). Combining these signals will provide the full sound spectrum (from 0 to 20000 Hz). Signals are captured with National Instruments data acquisition hardware using Labview software. A number of sources have already been recorded."
He adds, "To generate infra sound I will use an infra sound transducer device [2]. This device and associated amplifier-control unit, is designed to develop infra sound pressures within a controlled space, based on an arbitrary analog signal input. The full power frequency response of the system is from ~0.2 Hz to ~ 40 Hz. A pressure sensor feedback module will also be assessed. This sensor can provide a method of closed loop pressure control of the control space or alternatively, analog pressure signals may be provided as feedback from user supplied infra sound microphone or pressure sensing system (+100 mV /Pa signal recommended). The goal of this stage will be to ensure that the device performs within its specifications so as to provide a dependable base for further research."
