Acoustic Assessment Report
What is an acoustic assessment report (AAR)?
All businesses must have an environmental compliance approval (ECA) or environmental activity sector registry (EASR) from the Ministry of Environment and Climate change if it releases, or has the potential to release pollutants into the air, land or water. Depending on the nature of the operations, NAICS code, and location of nearby sensitive receptors (houses, hotels, schools, daycare, hospitals, etc) businesses may also be required to complete an acoustic assessment report (AAR).Acoustic assessment reports assess the off-property noise impacts of a facility at a nearby sensitive receptor to ensure compliance with NPC-300: Environmental Noise Guideline – Stationary and Transportation Sources – Approval and Planning.
How does one know if they need an Acoustic Assessment Report?
The Ministry of Environment and Climate Change (MOECC) has a four step process for determining whether or not facilities are required to prepare an acoustic assessment report.
Step 1: Identify Closest Point of Reception (POR)
Using a land use zoning map provided by the local municipality, the distance to the closest sensitive receptor and/or permitted sensitive land use must be identified. This includes lands that are zoned or permitted for future use, and includes premises such as:
- Permanent or seasonal residence
- Nursing/retirement homes
- Apartments/rental residences
- Noise sensitive buildings such as schools and places of worship
Step 2: Determine Actual Separation Distance
Once the closest points of reception have been identified from Step 1, a Scaled Area Location Plan drawing must be prepared. The scaled area location plan shows the distance between the noise generating equipment at the facility, and the sensitive receptors identified. Typically, measurements are made from either the nearest facility wall, or an outdoor noise source (i.e. a dust collector or cooling tower located off the building).
In rural, Class 3 areas, Points of Reception are limited to locations within 30 metres of a dwelling. In many rural areas, particularly farmland, there could be significant acreages of land that is not deemed noise sensitive.
Step 3 – Calculate Minimum Required Separation Distance
Separation distance is the distance between a noise source or closest facility wall, and nearest point of reception. It is important, as the Noise Screening Assessment has generalized separation distances (also known as setback distances) for various processes or industry classifications.
Industry with minimum 1,000m separation distance requirement for Acoustic Assessment Report
|21||Mining and Oil and Gas Extraction|
|221111||Electrical Power Generation|
|324||Petroleum and Coal Products Manufacturing|
|3251||Basic Chemical Manufacturing|
|3311||Iron and Steel Mills and Ferro-Alloy Manufacturing|
|3313||Alumina and Aluminum Production and Processing|
Equipment with 1,000m minimum separation distance
- Gas Turbines, Cogeneration or any other continuous or peak shaving electrical power generation equipment
- Arc Furnaces
- Asphalt Plants
- High velocity or pressure atmospheric vents such as Gas Process Blow Down Devices
- Rock, Concrete, or Aggregate Crushing Operations
- Individual Fans with flow rates in excess of 47 m3/s
- Individual Pressure Blowers or Positive Displacement Blowers with static pressure in excess of 1.25 kilopascal
If your business operations are covered by any of the above NAICS code, or your facility has any of the above listed equipment then the minimum separation distance between your facility and a sensitive receptor is 1,000m. If there are no sensitive receptors within this distance then no Acoustic Assessment Report will be required. If there is, then an Acoustic Assessment Report will need to be submitted with your Environmental Compliance Approval Application.
Industry with reduced minimum separation distances 300 – 500m.
The following industrial classifications have reduced minimum separation distance requirements as the nature of the operations are generally less significant than the major sources listed above:
|22112||Electrical Power Transmission, Control and Distribution|
|2213||Water Sewage and Other Systems|
|321||Wood Product Manufacturing|
|325||Chemical Manufacturing (except 3251)|
|326||Plastics and Rubber Products Manufacturing|
|327||Non-Metallic Mineral Product Manufacturing (except 32731 and 32741)|
|331||Primary Metal Manufacturing (except 3311)|
|332||Fabricated Metal Product Manufacturing (except 33271 and 3328)|
|335||Electrical Equipment, Appliance and Component Manufacturing|
|336||Transportation Equipment Manufacturing|
If a facility’s operations are not covered by any of the above tables, or equipment list the Ministry of Environment and Climate Change has a generic scorecard question that has to be filled out.
It takes into account:
- Building size
- Process equipment on site (cooling towers, chillers, compressors, boilers)
- Exhaust rate of all fans/blowers
- Hours of Operation
- Proximity to 400 series highways, provincial highways, and arterial roads
Depending on the ‘score’ received by filling out the questionnaire the facilities minimum separation distance is determined, and can range from 50 m to 500m.
Step 4: Statement Facility Meets Screening Requirements
If a facility can demonstrate that the minimum required separation distances exist, then the facility will not be required to complete the noise portion of the Environmental Compliance Approval Application. If the minimum separation distance criteria is not met, a facility is required to prepare an Acoustic Assessment Report (AAR).
What does an Acoustic Assessment Report Consider?
Acoustic assessment reports predict the off-property noise impact in accordance with MOECC guidelines. Typical sources of noise considered at the facility include:
- Rooftop HVAC equipment
- Cooling towers
- Process exhausts
- Process equipment located outside the building (dust collectors, etc)
- General building exhausts
- Noise from truck traffic
Assessments begin by identifying all significant sources of noise at a facility. ;Using a combination of equipment specifications and directly measured noise readings a detailed inventory of all noise generating equipment is prepared. Next, the noise is modelled. Unlike for Environmental Compliance Approvals for Air, the MOECC does not specific which acoustic modelling software has to be used. The MOECC only specifies that the ISO standard equations be used. ;The two most common software packages used are CadnaA and Soundplan. These software packages take all the sound level data collected at the facility, and predict the sound power levels at the identified receptors. Building the model takes into account the topography of the land, any existing noise mitigation equipment such as silencers, enclosures, barriers, etc.
The off-property noise criteria is broken down into 4 land classes, and each class has a specific limit depending on the time of day (day, evening, night).
Class 1 area– major urban centre, where background sound level is dominated by people and road traffic (i.e. City)
Class 2 area– between Class 1 and Class 3, which has sound levels similar to Class 1 during the day, but similar to Class 3 during evening and nighttime
Class 3 area– rural area where background sound level is dominated by natural sounds having little or no road traffic (i.e. small communities, agricultural area, cottage or resort area, wilderness)
Class 4 area– Class 1 or 2 area, that is intended for development with new noise sensitive land uses that are not yet built, is in proximity to existing stationary noise sources, and has formal confirmation from the land use planning authority with the Class 4 Designation
|Time of Day||Class 1 Area
|Class 2 Area
|Class 3 Area
|Class 4 Area
|07:00 – 19:00||50||50||45||60|
|19:00 – 23:00||50||50||40||60|
|23:00 – 7:00||45||45||40||55|
What if your facility cannot meet the NPC-300 limits?
If a facility cannot meet the NPC-300 limits, then a facility is required to prepare a Noise Abatement Action Plan (NAAP) to support the Acoustic Assessment Report. The noise abatement action plan outlines which noise mitigation measures will be installed, and the timeline for implementation. If a noise abatement action plan needs to be required, the MOECC will put a condition into the Environmental Compliance Approval (ECA) that an Acoustic Audit needs to be conducted by a third party after the installation of the equipment.
Rubidium Environmental has extensive experience designing, and installing noise control solutions. Check out our Industrial Noise Control Page for more information.