Monday, September 26, 2022

Noise versus Development: Residents and Regulators Caught in the Middle

Richard Patching, PEng, MEng, President, AANViS Board
Dan Clayton, MIoA, SLR Consulting, Member-at-Large, AANViS Board

There are often conflicts between a municipality’s/province’s needs for an industrial tax base and employment, good transportation links, and residents’ preference for a quiet environment. The municipality’s/province’s needs typically result in sound generation, and increasingly in areas where people live.

As urban areas and associated infrastructure/industry continue to increase, expand, and get closer to residential areas, the need to consider the acoustic compatibility of adjacent land uses becomes more apparent.

There have been recent examples of unregulated sound sources affecting residents, as reported in the Calgary Herald* on Monday, September 19, 2022.

The article reported that near Manassas, Virginia (USA), there is a large and growing concentration of facilities housing servers for cloud computing. They require substantial air-conditioning (AC) equipment to keep the servers within allowable temperature limits for operation, along with large banks of backup power generators—both high sound-generating equipment items.

For context of scale, the cumulative power requirements of the data centres in northern Virginia are roughly equivalent to the entire output of the North Anna Nuclear Generating Station and similar equipment. So why not regulate the sound from it?

In Prince William County, Virginia, the local ordinance specifically exempts air-conditioning sound from its limits, due to the warm climate.

There are now many complaints and protests organized to object to the constant whirring sound of the AC fans, especially the tonal components of which are irritating to residents.

Regardless of the local ordinance exemption, the local Amazon Web Services facility said that it has made it a priority to address the sound concerns of neighbours and is installing acoustic shrouds at this site to mitigate the situation.

Retrofits of this kind are usually more expensive and compromise efficiencies of the equipment, compared with assessing sound prior to construction and including appropriate mitigation into the design. Also, complainants tend to have a heightened sensitivity to sounds they have complained about, often requiring heightened control measures compared with having controls put in place during construction.

These kinds of uses are starting to appear in Alberta. So, let’s look there for a second.

Is it appropriate that only energy and utilities industries are regulated for sound in Alberta and other industries are not? This means that sound from mining and minerals, manufacturing, data storage/communications, waste transfer, entertainment, and leisure uses, to name a few, are not typically proactively assessed or regulated. Even assessments of the sound generated from these uses, including transportation (let’s ignore rail for now in most locations😉, although in recent years the City of Calgary has required inclusion of rail noise in traffic assessments) in many cases, are typically not required by municipalities to inform a decision in order to grant the development permit. This means that we’re not assessing the risks in terms of sound and appropriate mitigation, in many cases, and just letting things “land as they may.

Is it best to “just build it and see how we get on with complaints”?

Noise complaints are on the rise, which is showing that effects are already apparent. An article published as part of International Noise Awareness Day around data in the US (regulations for sound are not too dissimilar to that in Canada) concluded that, “Commonly only 5 and 10 percent of residents exposed to noise actually complain or participate in any related activity.” That’s an overwhelming percentage of people who don’t complain who are potentially affected. Some will think that complaining won’t bring change, others may think that’s the way it is, or various other reasons.

What about Bylaws?

The Bylaws are typically enforced in reaction to a complaint, rather than the proactive assessment and control of sound to prevent effects on residents. The language in Bylaws is often too general, contradictory, and outdated compared with the industry-regulated approach to assessing sound in Alberta.

There are similar situations in other provinces in Canada, too. Alberta has been given merely as an example.

A typical statement in a Bylaw is

…No person being the owner or occupier of real property knowingly shall allow or permit such real property to be used so that noise or sound which emanates therefrom, disturbs the peace, rest, enjoyment, comfort, or convenience of any person or persons in the neighbourhood or vicinity.” There are also many Bylaws that don’t even mention sound.

Some bylaws have sound level limits, but most don’t. Those that do, typically contradict the regulations with higher sound level limits.

Sure, these can be relevant to urban areas with higher ambient sound levels, but this is not the rule for all situations. Ambient sound levels can be lower within the municipality/county, especially larger and more diverse ones, in terms of distribution of sound sources. This could underestimate the effects on residents.

Sleep disorders and related health effects have been linked to sound level, and related annoyance, in various research conclusions.

So, should we do more?


*Calgary Herald article reprinted from an Associated Press article found at

Thursday, September 22, 2022

Thursday, September 1, 2022

Let's Get Social in Edmonton

After the success of our Calgary social event, we wanted to make sure that our members and potential members in the Edmonton area were not left out. We look forward to seeing you live in September!

Thursday, July 21, 2022

Let's Get Social

This is a chance to meet up with and connect with other acoustics, noise and vibration professionals in Alberta. Please RSVP, so we have an idea on the number of people attending.


A Different Kind of Conference


October 28, 2022

There are many conferences for acousticians by acousticians (e.g., CAA, Inter-Noise, Noise-Con, International conferences on Wind Turbine Noise, the International Congress on Acoustics).  While interesting and of value, it is sometimes challenging to consistently find practical applications to our day-to-day work solving problems for our clients. Our upcoming conference, like those of AANA in the past, provides an opportunity for Alberta acousticians to share what they know with others interested in the field, and in particular with those in industry who might need to hire acousticians and want/need to get an idea of the ‘black magic’ we practise. (A lot of people really dislike logarithms.)

This October’s 1-day conference puts a focus, in part, on the business of acoustics—how workplans and proposals are developed and priced, and what goes into being a consultant. There are also sessions on best practices in noise and vibration solutions, sometimes discovered by trying things that should have worked but didn’t. We will also get a look at a student project and current trends in acoustics education in Alberta. Some sessions are still evolving.

One of AANViS’ primary objectives is education of interested parties. Our full morning Introduction to Acoustics by Steve Bilawchuk has traditionally been used to help train regulator staff in the principles of acoustics, as they were the ones responsible for administering the noise control directives.  They were not exclusively acousticians but needed a grounding in the field. Besides regulators, this course is also of value to architects, engineers and project managers in environmental, transportation and energy whose projects are sometimes affected by noise or vibration issues.

We are especially proud of our panel on noise regulations in Alberta. We have gathered representatives of the AER, AUC, Alberta Infrastructure and city transportation to talk about the noise regulations that affect projects in Alberta. This is a great opportunity for dialogue between those who make and administer the rules and those who must operate within them.

In fact, the entire day is filled with opportunities for dialogue and developing a better understanding of what goes into acoustics work. For more details, please visit our conference page. Register now for the early-bird rate.

Tuesday, February 15, 2022

Smart Phone or Sound Level Meter?

Jonathan Chui, Stantec Consulting
Justin Dos Ramos, Nureva Inc.

In 2022, most people in Canada have a smartphone.  Since smartphones have built-in microphones, electronics and processing, downloading of a free or low-cost application is all that is needed to turn them into a sound level meter.  However, are smartphones accurate enough to replace traditional ANSI Type 1 or 2 sound level meters?

Kardous and Shaw (2014) investigated the suitability of smartphone apps for occupational noise measurements. They studied a sample of smartphones and tablets with 4 Apple devices, 10 iOS apps, 5 Android devices and 4 Android apps. Measurements were conducted in a diffuse sound field in a reverberant noise chamber. Seven levels of broadband noise, ranging from 65 to 95 dB in 5 dB increments, were set as reference measurements and validated by calibrated measurement systems, including a Type 1 sound level meter. In total, over 1680 smartphone measurements were analyzed. Measurement results from four iOS apps showed mean differences within ±2 dB/dBA. This is good enough for ANSI Type 2 and Occupational Safety and Health Administration (OSHA) standards and suggests that certain apps for Apple smart phones and tablets may be considered reliable and accurate for use in occupational noise measurements. On the other hand, the Android-based apps did not offer the functionality and accuracy needed for occupational noise assessments.

Murphy and King (2016) did extensive testing of 100 smartphones, including 65 iOS-based devices (7 models) and 35 Android-based devices (18 models) to assess their suitability for environmental noise measurements. Four iOS and three Android apps were tested. In total, there were 1472 tests. Measurements were conducted similarly to Kardous and Shaw, but reference noise levels were set at 50/70/90 dBA. The background sound level in the room was 27 dBA.

Android devices had much higher variability in comparison to iOS devices. Different hardware used in the variety of Android devices is likely a big factor. Overall, Android devices under-measured levels while Apple devices over-measured levels and offered significantly better measurement consistency and reliability.  Newer phones were also more accurate, but it was unknown whether they are equipped with better microphones or the older phone microphones deteriorate over time. In general, though, smartphones were more accurate at middle of the road noise levels of 50/70 dBA in comparison to the lowest (background only at 27 dBA) and highest (90 dBA) noise levels. This suggests smartphones may not be suitable for some ambient, background noise or hazardous noise level measurement uses. The conclusion was that smartphone apps on the whole are not quite ready to replace traditional SLMs, but a combination of good hardware and software can produce a smartphone that accurately measures sound level.

A more recent paper by Shahnaz and Brown (2020) compared the accuracy of smartphone apps from both Android and iOS devices to a Type 1 sound meter in real world environments (living room, classroom, restaurant, nightclub, public transit, and a fitness class).  The results indicated a variation of 3 dB or greater between the apps and the sound meter were common. They concluded that these apps should not be relied on as an accurate tool to determine hearing protection measures because of the amount of inconsistency between apps and devices. However, the smartphone apps are good for providing a general idea of the sound level in any environment.

Smartphones with external microphones and apps that allow calibration of the sound level were not considered. These would not likely be used by the general public. The combination of hardware and apps result in a wide range of deviations in measurement results.  A singular smartphone measurement is most likely not a reliable indicator of a true noise level, but a large set of these measurements may converge to the true noise level. 

New smartphone models and apps are introduced yearly, and overall sound measurement accuracy and reliability could improve in the future.  Smartphones are ubiquitous tools that can provide useful general noise information. They are a convenient means to explore everyday acoustic environments and open up the potential of large, crowd-sourced sound databases. However, they should not be considered a replacement for a purpose-built sound level meter when precise and reliable measurements are required in a sound assessment.


C. Kardous and P. Shaw, “Evaluation of smartphone sound measurement applications”, Journal of the Acoustic Society of America, 135, 186-92, (2014).

E. Murphy and E. King, “Testing the accuracy of smartphones and sound level meter applications for measuring environmental noise”, Applied Acoustics, 106, 16-22, (2016).

N. Shahnaz and S. Brown, “How accurate are these smartphone sound measurement apps?” Canadian Audiologist, 7, (2020). 

Jonathan Chui, PEng, INCE is a Senior Associate, Team Lead in the Noise Management Group at Stantec Consulting.

Justin Dos Ramos, CET is with Nureva Inc.

Saturday, February 12, 2022

Update on Stopping Train Whistles through the Banff Townsite

Richard Patching, PEng, MEng

Some residents of Banff have petitioned the town council to restrict or eliminate the sounding of train whistles in the vicinity of the town. This was reported by the Rocky Mountain Outlook on March 29, 2021 and on Global News on April 8, 2021, after the presentation of a delegation on March 22nd.

AANViS reported in a previous post that during the May 10th meeting of the Town Council, the council passed a motion to have the Town’s Administration consult “with the railroad operator on the feasibility of creating a railway quiet zone along the railway corridor in the vicinity of Banff, and report back to Council before the end of Q3 2021.”

The Town of Banff is the road authority for the railway crossing at Norquay Road, but Parks Canada is the authority for the crossing at Compound Road northeast of the main townsite. Based on an e-mail from CP to the town (November 17th, 2021), the Town would have to hire an engineering firm to conduct a compliance audit to meet all standards for the Norquay Road crossing. The member of the public who made the original request for the quiet zone (aka whistle cessation) would need to engage Parks Canada for the Compound Road crossing.

There have been long-running discussions involving CP, the Town and Parks Canada concerning illegal pedestrian rail trespassing near the industrial area between Compound Road and Norquay Road. CP indicated that they would not likely approve whistle cessation until an engineering solution to the trespass issue was implemented. We assume that such a solution would also have to address the issue of wildlife trespass onto the tracks, although this was not mentioned in the town’s documents.

The town council decided December 13th, 2021 to delay engaging an engineering firm to conduct the audit at Norquay Road until an engineered solution to the pedestrian trespassing issue has been approved. This may end up being similar to the situation in Canmore.

Silencing the train whistles in town makes for a more pleasant experience, but may be counter-productive if measures are not also taken to keep wildlife (and humans) off the tracks. At present, that measure continues to be the sounding of the horns.


Richard Patching is President Emeritus of Patching Associates Acoustical Engineering Ltd.

Thursday, January 20, 2022

Noise Conference Rescheduled

 Spring Noise Mini-Conference Re-scheduled to October 2022

Once again, COVID-19 restrictions have led the AANViS board has decided to postpone the 1-day mini-conference from April 22, 2022 to October 28, 2022. The location has not changed and we are in the process of contacting all of our speakers and panellists to make sure they are still available.

If you are unfamiliar with the plan for the day (or have just forgotten it over time), visit our conference page on this website. We look forward to seeing you this Fall.

Monday, October 4, 2021

Stopping Train Whistles through the Banff Townsite

Richard Patching, PEng, MEng

Some residents of Banff have petitioned the town council to restrict or eliminate the sounding of train whistles in the vicinity of the town. This was reported by the Rocky Mountain Outlook on March 29 and on Global News on April 8 of this year, after the presentation of a request from a delegation on March 22.

During the May 10 meeting of the Town Council, related correspondence, including written and verbal submissions, was received and the council passed a motion to have the Town’s Administration consult “with the railroad operator on the feasibility of creating a railway quiet zone along the railway corridor in the vicinity of Banff, and report back to Council before the end of Q3 2021.”

The Rocky Mountain Outlook article noted that one of the most impacted properties is the Mount Edith House seniors’ residence, which backs onto the train tracks (shown here). The report states that there are no noise-attenuation walls at this location. A visit to the site indicates that the band of evergreen trees between that building and the tracks is insufficient to address community concerns.

In the 1970s and 80s, the Canada Mortgage and Housing Corporation (CMHC) produced a document entitled CMHC - Road and Rail Noise Effects on Housing, which specified ‘acceptable’ levels of noise from trains, in particular between the ‘whistle points’ which are 400 metres from any uncontrolled level crossing. Under the Railway Safety Act (R.S.C., 1985), trains are normally required to sound their horns within the whistle points until they were actually occupying the level crossing, or when it is required for safety reasons such as trespassing people or animals. The Act [section 23.1 (1)] allows municipalities to pass a resolution to discontinue use of train whistles under the conditions now set in motion by the residents’ petition. There are only limited measures to prevent animals (who cannot read the signs) from accessing the tracks.

The Global News video shows the level crossing with crossing bars, so it is ‘controlled,’ but there are free-running animals in the Banff area, and access to the tracks within Banff is not consistently blocked by fencing. It has been noted that spillage of grain has attracted animals to the tracks in the past, potentially bringing wildlife onto the tracks and requiring the sounding of the trains’ horns to drive them away.

Previously, the nearby Town of Canmore required developments outside a corridor adjacent to the CP tracks to comply with the CMHC directives. This effectively sterilized the narrow corridor from residential developments within the mountain valley location. Fencing on both sides of the tracks has been installed to control access and some years back, the Town of Canmore was able to drop this non-residential building requirement from their planning regulations. This may have coincided with their establishment of a rail quiet zone, as is being requested in Banff.

The original existence of the Towns of Canmore and Banff is due to the presence of the railroad. The mine under the Three Sisters Mountain, and the mine at Anthracite (currently under Lake Minnewanka) supplied coal for the locomotives, and Banff was intended to support tourists attracted by the local hot springs, scenery, and wildlife. Silencing the train whistles in town makes for a more pleasant experience, but may be counter-productive if measures are not also taken to keep wildlife off the tracks which would still require the sounding of the horns.

As of the October 4, 2021 Banff Town Council meeting, there does not appear to have been any further information from the Town’s administration nor from CP Rail (

Richard Patching is President Emeritus of Patching Associates Acoustical Engineering Ltd.

Friday, September 24, 2021

Noise Monitoring for Renewable Energy

Henk de Haan, dBA Noise Consultants

Many a tome has been penned about sound level monitoring, and many more could be added. Some of my incomplete thoughts on it are offered here.

Under most regulatory regimes, strategies for noise and sound monitoring are determined by the situation and the dominant noise sources at hand, and not by whether the source is renewable or non-renewable. Continuous sources are typically easier to monitor than sources with a highly variable noise emission, such as wind turbines.

Prior to constructing and operating any new development, getting an idea of what the current soundscape entails helps to put future noise levels into perspective and is therefore recommended. I use the word “sound” to indicate that the acoustic signals we hear are not all experienced as noise. Noise is unwanted sound, and the soundscape may include both appreciated sounds (e.g., songbirds, leaf rustle) and unwanted sounds (e.g., an existing non-renewable energy facility or other sources not covered by most noise regulations, such as highways or gravel operations). In that respect, ambient sound level monitoring is not any different for renewable energy compared to other facilities.

The monitoring of ambient sound levels is not required nor encouraged according to regulations in Alberta or British Columbia, but frequently requested by residents close to new developments such as a new wind farm. Apart from satisfying popular demand, the only time you get to measure the unaffected soundscape is before construction starts. Therefore, I believe that ambient sound level monitoring should be actively considered before any development, renewable or otherwise, unless the new development will not generate substantial noise. The cost associated with noise monitoring is minimal compared to the investment in the renewable’s facility itself.

Monitoring of sound levels during construction can help one gain insight into and limit noise levels associated with construction, provided noise limits are enforced; what gets measured for enforcement purposes gets done, while what gets measured for general insight often only gets discussed. Sources such as tonal backup alarms, loud radios, pumps, light tower generators running during the daytime may cause unnecessary grief, while solutions such as broad-band backup alarms are readily available.

Monitoring during operation can provide insight into noise levels, associated with the new facility. Monitoring, however, needs to be part of enforcement of applied noise thresholds. I, therefore, believe that the regulator should conduct noise monitoring as part of their enforcement as well, and not only oblige operators to conduct noise monitoring. Regulatory noise monitoring will increase public confidence. Noise from wind farms is dependent on weather and meteorological conditions, such as atmospheric stability, and with larger turbines this dependency may increase. Predictions made using a relatively simple standard like ISO 9613 are valid for a single weather and operations scenario, and receptor-level noise levels can be expected to deviate frequently from the predicted value. Longer term noise- and weather-monitoring for receptor-level noise levels and their weather dependency can be helpful to increase insight into their dependency and confirm predictions. It can also be helpful to develop a science-based and accepted protocol for such monitoring.

For more continuous sources (e.g., solar power, biomass), where sound noise generation is relatively steady, such extended monitoring is probably not required. Noise from inverters has a continuous character, and dependency is restricted to insolation (i.e., the varying level of electrical generation due to the incident solar intensity). Short-term measurements may, therefore, be sufficient.

Alternatives to noise monitoring could include model calculations, based on verified emissions combined with model calibration. Such an alternative could be useful in situations where receptor-level noise monitoring includes significant difficulties or where compliance can only be predicted with a significant margin.

Henk de Haan is President and Sr. Consultant at dBA Noise Consultants

Friday, June 18, 2021

Semi-Permanent Noise Monitoring

Jonathan Chui and Azar Sagiyev, Stantec Consulting Ltd.

Semi-permanent noise monitoring equipment with remote access has been available for at least a decade, but the technology has evolved with advances in internet speed and wireless connectivity.  Early on, we spent considerable time setting up an account with the wireless service provider and many hours struggling with the cell modem IP configuration.  This has improved recently.
While permanent noise monitoring systems are common for airport authorities and marine port authorities in large Canadian cities, semi-permanent systems have been effective for noise monitoring in short-term construction and operation industrial activities. Most semi-permanent noise monitoring systems consist of the following main components:
  • Sound level meter, pre-amp and microphone
  • Weather station
  • Power source (i.e., AC and/or DC power)
  • Cell modem
  • Data storage
Semi-permanent systems have many advantages, which include
  • Providing continuous noise monitoring for intermittent events with unplanned schedules (e.g., construction activities)
  • Reducing multiple visits to the monitoring site, especially for remote locations
  • Giving easy access to real-time noise monitoring results for users (e.g., clients, consultants, other stakeholders) via the internet
  • Providing a noise threshold exceedance alert (i.e., SNS message) for immediate corrective action
  • Providing sufficient data-sampling
  • Automating the reporting process
Challenges associated with semi-permanent systems include
  • Data transmission is limited by cell coverage (satellite data providers are available but at significantly higher cost)
  • Connectivity can be intermittent in remote locations
  • Remote (e.g., cloud) data storage of audio recording is limited by connectivity
  • Continuous power sources may be required in some systems
  • Post-processing and data management can be labour-intensive due to the large amount of collected data
Semi-permanent systems come at higher cost; however, they provide versatility and functions not available with portable systems. The use of semi-permanent systems may be justified for long-term (e.g., multiple months) monitoring programs where intermittent and unplanned site activities may occur. Semi-permanent-to-permanent systems are also an indispensable tool for major infrastructure projects that require long-term data trends, such as large airports, marine ports and highways that undergo major operational changes or are expected to receive steady increase in traffic in long-term.

Are Electric Cars Quieter than Gas-Powered Cars on the Road?

The number of electric vehicles (EV) is increasing in Alberta and across the globe. While this will positively impact greenhouse gas emissions in our cities, the impact EVs may have on road noise is less well known. EVs are undeniably quieter than their internal combustion engine (ICE) counterparts at start-up and while “idling.” However, road-pavement noise becomes dominant at highway speeds, making EVs and ICEs similar. 

Patching Associates Acoustical Engineering (PAAE) measured pass-by noise levels of locally available compact SUVs, comparing EV and ICE models on a local Alberta highway at various speeds. The results are shown below and indicate that at the tested speeds of 20+ km/h, pass-by noise emissions of EVs and ICEs on typical local pavement did not differ significantly.

While electric vehicles have the potential to reduce noise with very slow speeds (under 20 kph) and during idling and acceleration from standstill—where engine-generated noise dominates, such as in very congested city centres—these data show that the rise of EVs is not going to drastically change the situation for Alberta residents who are currently most affected by roadway noise—those living near busy arterial and highway road infrastructure.

Thursday, June 17, 2021

Paradise Lost: The Wilderness is Not What it Used to Be

Henk de Haan & Virgini Senden

Freshly vaccinated, we decided it was time for a change of scenery, so we packed our recently-acquired second-hand travel trailer and hit the road. The trailer, like any other trailer, is packed with amenities to turn it into our home away from home—heating, cooling, cooking facilities (an oven and a microwave), a fridge with freezer, and a bed with a real memory foam mattress and a bedside reading light. After a lifetime of camping in small, portable tents and sleeping on wafer-thin camping mattresses not worthy of the name—the epitome of luxury.  All these amenities require electric power, of course, either supplied via batteries or via a hookup at the camping spot.

Our first camp site was not equipped with power at all. To prevent draining his batteries, a neighbouring camper schlepped a transportable generator in and ran the generator for about an hour each day around lunch time. The first time, I was sitting outside reading, enjoying the beautiful weather, the songbirds, the busybody squirrel—it was heaven! The generator in question was not equipped with any noise-mitigating features, and it showed. The birds, the squirrels, the rustling leaves—all gone. I sighed, went inside and closed the door.

When camping, you’re more exposed to the weather, and it can turn nasty. We had a spot of rain overnight, and when I woke up early the next morning, everything inside felt a bit damp. I sneaked out of bed and decided to try out the heating system to get rid of the dampness, thus making getting up a more pleasurable experience for my significant other (she’s sensitive that way). The furnace came on, and so did the fan. It turns out the fan is a small, high-performance fan, tearing the peaceful slumber of my beloved to pieces. I tried to restore peace by offering breakfast in bed, which was (thankfully) gracefully accepted. A golden rule for both camping and staying in hotels: bring earplugs!

Our next campsite, located in a popular National Park, had it all—or almost everything in the eyes of management. Opposite from our campsite, a construction crew was working to erect a new building quite close to an existing, also fairly new, one. The crew put in admirable hours, even on Saturday and Sunday—twelve-hour shifts at least. For their power, they relied on a generator, not on the outlets of the building less than 25 metres away. When we pointed out the option of plugging in their equipment to the camp operator, the young man stared at me and said that generators were allowed between 7 AM and 11 PM, completely missing the point.

The weather on this camping trip was warm. Neighbours a few sites over invested in an RV the size of a city bus, equipped with at least three AC units. Obviously, they liked it cool, including overnight. We reached for the ear plugs once more. Did I mention the grass mowers? Management likes the grass on the campsite short.

All in all, we had a lovely outing, but not a quiet one. Thankfully, we were not confronted with rowdy neighbours playing their favourite music over the outdoor sound system that any decent trailer comes with. I’m sure, however, we will in the not-too-distant future. I want to go home.