Posts Tagged ‘noise snare’
John Mar’s statement is technically correct, unfortunately, the measurement methods by Calgary Bylaw are completely wrong. We touched on why the new bylaw is flawed in our post about the Noise Snare, where our Mercedes Benz C63 AMG Black Series failed the bylaw’s definition of objectionable noise. With the help of curious Beyond members in the discussions thread, we were able to figure out why our new and completely stock vehicle was able to fail the test so badly. Let’s start from the top.
It all started with City Council wanting to control objectionable noise, mainly, from motorcycles in areas such as 17th Ave SW, where the roar of their loud pipes makes it difficult to carry conversations on the street. In the City Council meeting on May 18th, 2011, a report was tabled that claims:
Vehicles that are imported or manufactured in Canada are required to meet federal guidelines for noise emissions. The highest permitted exterior noise level for a new vehicle is 84 decibels. These levels will increase marginally as the vehicle experiences normal operating wear and tear or more significantly, if the vehicle is not maintained or is modified from the original manufacturer’s equipment to deliberately emit higher noise levels.
The Traffic Bylaw 26M96 would be amended to make it an offence for any vehicle to exceed the maximum decibel limit. It is recommended that the decibel limit be set above the maximum level specified at time of manufacture to allow for vehicle noise levels increasing with normal wear and tear.
The second open house for the the City of Calgary’s new weapon to combat excessively loud vehicles wrapped up yesterday evening after 469 vehicles rolled through the Noise Snare. We previously mentioned that some vehicles straight off the dealer showroom would exceed the 96 decibels threshold the City has chosen and we wanted to test it out with a brand new 2012 Mercedes Benz C63 AMG Black Series.
First, a little bit on how the Noise Snare works. The vehicle mounted device constantly monitors ambient noise levels using a microphone placed above the rear tire of a parked bylaw vehicle. When a pre-set level is hit the two cameras are activated and begin recording clips of the vehicle approaching as well as it driving away from the noise snare. The concept is simple, but the implementation will be a lot trickier than deploying say a photo radar van that snaps a photo of speeding vehicles. With noise, there are many other factors at play that need to be under control that a bylaw officer may or may not have control of such as: distance from vehicle being measured, sound reflections off buildings or other vehicles and of course how the dB meter readings are weighted.