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Noise & Vibration_1

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Key Findings

  • Measured noise levels at representative noise-sensitive receptor locations within the Study Area are consistent with levels expected within a mix of urban and suburban areas, where road traffic and industry are the dominant noise sources. These noise measurements include a daytime range between 48 dBA1 to 73 dBA and a nighttime range between 43 dBA and 70 dBA
  • Typical ambient vibration levels measured at representative vibration-sensitive receptor locations within the study area range between 0.0067 mm/s2 and 0.0644 mm/s2 in theatres, 0.0826 mm/s (outdoor) at a recording studio and 0.016 mm/s in a hospital Magnetic Resonance Imaging (MRI) room. Current ambient vibration levels at these sensitive receptors are below the typical threshold of human perception
  • Find out more: Noise & Vibration Information Sheet

1dBA refers to the noise level adjusted to how humans experience different frequencies. Typical ambient daytime noise levels — as experienced by humans — are 53 to 67 dBA in an urban area whereas a military jet take-off at 25 metres is 140 dBA.

2mm/s refers to ground-borne vibration velocity, where 0.1 mm/s is equivalent to 72 VdB or the approximate threshold for human annoyance, and 65 VdB (0.045 mm/s) is equivalent to the approximate threshold of human perception. VdB refers to the vibration level adjusted to how humans perceive vibration.

Noise Monitoring Equipment located at Wardell Street

samples of noise monitoring equipment
samples of noise monitoring equipment

Spotlight Case

The 3M Quest SoundPro noise monitor displayed in Image 2 measured sound levels at locations in the Study Area. Image 1 shows the noise monitor in a protective case at Wardell Street. Noise monitors provide advanced sound level monitoring and comprehensive data analysis. Noise monitors typically consist of an electronic device, preamp, microphone, windscreen to reduce sound disturbances and a digital display to view real-time frequency analysis. Typically, monitors are left in place for a specified duration (for this project, five days). Measurements are saved at select fixed intervals (for this project, every 15 minutes) which are stored in the device and then can be used to process and evaluate noise levels. The measurement data collected are provided in the Environmental Conditions Report. These baseline monitoring data can provide a benchmark for comparison with project noise impacts, which are predicted through various measurement and modelling tools.

Methods

Noise measurements were collected at 16 locations representative of noise sensitive receptors near the representative Initial Business Case (IBC) alignment. These locations – residential dwellings and places of worship – were selected based on proximity to the representative alignment and represent spaces and areas of human activity that are sensitive to noise.      

Ontario Line: Noise Measurement Locations

map graphic showing the location of noise monitoring equipment for the study

Vibration measurements were collected at seven locations representative of vibration sensitive receptors near the representative IBC alignment. These locations - theatres, a recording studio and a hospital - were selected because they accommodate spaces and equipment that are potentially more sensitive to groundborne noise and vibration than typical residential buildings.

Ontario Line: Vibration Measurement Locations

map graphic showing locations of vibration monitoring equipment for the study

 

Preliminary Potential Impacts & Mitigation Measures for Further Study

Construction

Operations

Potential Impacts

  • Annoyance
  • Sleep disturbance
  • Interference with activities

Potential Mitigation Measures

  • Use equipment with low vibration levels, enclosures and silencers, where possible
  • Use construction equipment compliant with noise level specifications in MECP guidelines
  • Implement temporary construction site noise barriers
  • Off-site construction of components, where possible
  • Restricting construction hours, where possible

Potential Mitigation Measures

  • Noise & vibration reduction at the source (e.g., rail dampers, continuously welded rail, and quieter heating and ventilation)
  • Noise walls
  • Resiliently supported rail ties and high resilient fasteners
  • Ballast mats or floating slabs

Future Studies

  • Additional noise and vibration measurements, as required
  • Noise and vibration impact studies (stationary sources, rail and construction impact modelling)

 

image of noise monitoring station

Long-term construction noise monitoring station, with solar power and remote telecommunications

image of noise logger

Noise logger capturing ambient noise

 

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