Environmental Science Series online seminar 2/9/2020
Sound-thinking for a quieter environment - Managing Noise Around Us

ANDREA HINWOOD: Good afternoon everyone?
It's my pleasure to welcome you online today, to EPA Victoria's 9th environmental seminar series,
on Sound-thinking for a quieter environment, managing noise around us
with our special guest speaker, Marion Burgess,
from the University of New South Wales.
I'm Dr. Andrea Hinwood,
I'm Victoria's Chief Environmental. Scientist at EPA Victoria.
Before we do much more,. I'd like to begin by acknowledging
the traditional custodians of the land on which we meet today
and pay my respects to the Elders past and present.
And I extend my respect to the Aboriginal and Torres Strait Islander people,
colleagues, staff and students who might be listening today.
Given we're meeting from all over the globe,
I'd also like to acknowledge our. First Nations people everywhere
and thank each of you for giving your time
to come and listen to this event on noise.
Just a few notes on this live stream event,
I personally am having some internet issues
and in fact, I can hear a little bit of feedback while I'm speaking,
which I hope you can't.
I'm also seeing a hazard light come up on my system,
so please be patient with any technical issues that we might be having.
This is only our second time holding this series in this format,
so I'm hoping we'll be able to resolve any bugs.
The structure of today's event will feature an introduction by myself,
and then a presentation by Marion Burgess
With some time for questions and answers after that.
The event will be recorded live, so if you need to leave early or miss parts,
you can watch it again later via EPA's website.
We also have live closed captions to make sure it's accessible for all.
We should be putting a link to that in a Q&A button.
So if you have a look at the bar on your screen,
you should see a little icon with some question marks, that's the Q&A.
That's also where you put your questions in,
but it's where you can access that live captions facility.
We will open the question and answer session now,
but we'll respond to questions after the presentations
and we'll try to get to as many as we can.
If we can't get to all of them, we'll respond via email at a later time.
So if you can provide your contact details that would be useful,
so we can get back to you on those matters.
So today, we're here to discuss sound thinking for a quieter environment,
managing the noise around us.
It's a topic that's important to EPA Victoria,
and clearly by the very large number of registrations we have to this event
from a range of locations.
It's obviously a topic that many people are also equally interested in.
Our world is full of sound, at the moment,
I'm sitting inside with the wind raging around my home,
and I can hear it quite loudly and I hope you can't.
When noise is or sound is loud and intrusive, we refer to it as noise
and in an urban environment, noise pollution can come from many sources,
it can come from our neighbours, commercial, industrial sites,
construction sites, roadworks and transport of course.
And we, the EPA Victoria receive many complaints every year
from the public about noisy neighbours, vehicles, venues,
and of course noise from industry and construction.
Residential noise is one of the most common sources of noise for Victorians
and it can also be the most annoying.
And that is noise that comes from a residential property
and what's around it, and it can come from stereos or radios.
Some of you may not like my opera playing on a Sunday morning,
televisions, air conditioners, lawnmowers,
and power tools that people use around their home.
And of course, construction activities create a lot of noise
while people are renovating homes and apartments.
Perhaps it's not surprising that we have recorded a major increase
in noise pollution in the first six months of this year
because of the restrictions associated with Coronavirus.
And about half of all noise pollution calls to EPA were about residential noise.
And for those of us living with either stage three or four restrictions,
you may have noticed that yourself because you're home more,
some stats for you, we saw or have seen a 45% overall increase
in low-level noise reports in comparison to last year.
Noise pollution reports doubled from February to March,
reaching their highest in July at 548 reports.
Noise queries as distinct from pollution reports
which includes questions about noise limits or legislation.
They also increased this year in May with 432 queries.
Almost half of the inquiries were about residential noise including loud music,
traffic and low-level construction.
We're all spending more time at home,
it's a fact of life that we all make noise in some way.
And what's enjoyable to some people will certainly be annoying to another.
And although noise is inevitable, and you know,
we accept that to an extent, managing noise is also really important,
because noise does have impacts on human health.
And so it's really important that we consider it
in terms of people's health and wellbeing.
We know that ongoing exposure to noise can lead to a wide range of issues
such as headaches, increased blood pressure, fatigue, irritability,
poor reading comprehension and attention in children
and of course, if noise is really loud,
we know that it can cause hearing damage.
There are a wide variety of studies that have been conducted
on the health effects of noise.
There's a strong relationship between high noise levels
and cardiovascular disease.
I think most of us know about sleep disruption,
and of course, that in itself can have a range of problems
which affect behaviour and performance and can have other health consequences.
Chronic exposure to transport noise has been reported
to be associated with elevated blood pressure,
but also cardiovascular disease and specific events.
And it's also been associated with an increase in accidents.
There are many people in our community who are more vulnerable
to the effects of noise, such as the sick, elderly and young
and those with chronic health issues, but also our shift workers.
And let's not forget our fauna, our native fauna in particular.
Noise can also have impacts on non-living materials as well,
such as when old places or newly constructed buildings
have developed cracks when there's a stress of explosive sound.
EPA, Victoria Police, local government and other government agencies
all share responsibility in this space, so it can be a little confusing at times.
Under the Environment Protection Act,
EPA has an important role in protecting the community from noise pollution.
And we have a framework from control of noise, from residential premises
and we have State Environment. Protection Policies
that are focused on assessing the impact of noise on the environment
but also with some tools to help us deal with it.
And it's probably worth saying that our role is really about unreasonable noise.
We have specialists in noise and acoustic science,
we have Environment Protection Officers
and Officers for the Protection of the Local Environment,
who respond to noise pollution events.
And our staff actually conduct, you know, over 100 assessments each year,
and in particular our Offices for Protection of the Local Environment
in local government are embedded in local government.
They undertake more than 150 noise assessments a year.
And of course, when noise is found to be unreasonable,
from particularly industrial sources, we issue pollution abatement notices.
So we work with and provide advice and guidance
to government in the industry to minimise noise from projects.
And we have a range of guidelines and information to help explain
what noise might be unreasonable, and how to assess it.
And of course, any noise from a residence
can be unreasonable at any time of the day, depending on, you know,
how loud it is, its intensity, the type of noise,
what the sound is actually like and how close people are
and how long it continues for.
But there's an awful lot that can be done to prevent these issues,
which is why we talk about them in these types of seminars.
So that we can reduce the negative effects of noise, for example,
we do have regulations that we can actually apply to restrict noise.
There are always the use of engineering noise control options
for a range of different devices.
Traffic management strategies can decrease noise,
and of course public awareness about noise issues more generally.
So on this note, to talk with us today
about this important area is our guest speaker, Mrs. Marion Burgess.
Marion is an acoustics researcher at the University of New South Wales
and for over 40 years, she has primarily worked in noise
including building, environmental, occupational noise measurement,
assessments, control and research,
and she's got a diverse experience across teaching, research and consulting.
Since retiring in 2017,. Marion has continued an active involvement
in an honorary position at the University of New South Wales,
and she was awarded the Order of Australia in 2015,
for significant service to science in the field of acoustics,
particularly noise management, and to professional scientific organisations.
She's published widely, and she regularly participates in national,
international acoustics meetings,
and is currently chief editor of the journal Acoustics Australia.
She is the past president of the International. Institute of Noise Control Engineering,
and a previous president of the. International Commission for Acoustics.
She's been involved from the outset in the International Commission
for acoustics goal for an International Year of sound,
which happened to be 2020.
However, this has been scheduled now for 2021.
So, clearly, Marion is absolutely a wealth of experience and knowledge,
and who will be able to assist us in talking about these issues today.
And I'm sure you'll be joining me virtually in welcoming Marion today.
Please Marion, take it away.

MARION BURGESS: Thank you very much Andrea,
for a very nice introduction there and thank you for your kind words.
In this presentation today, my goal is to talk about a lot of the aspects of sound
and many of those you've already mentioned
and I'll hopefully be picking them up as we go through the presentation.
So if I can have the next slide, please.
Alright, so sound, what is sound?
Sound is all around us and it's actually fundamental to our social structure.
Just imagine how boring life would be if we could hear nothing, you know,
we would go out walking and there would be no sound of
the wind rustling in the trees, there'd be no sound of the birds in the trees
and everything like that, so sound is part of our social structure.
There are some very basic requirements for sound,
it's a safety, warning of danger, and also of course communication.
And also there is other aspects too to sound and that's cultural expression,
spiritual expression, celebration, recreation, etc.
So, we have a very important range of activities associated with sound.
Next slide, please.
So, what is our goal?
We really wanna keep sound in its most desirable form,
we wanna be able to keep it so that it sounds good to us,
so that we like the sound.
In that manner we need to control sound within spaces,
to ensure that the sound gives enjoyment,
but also then minimises the sound that's going outside that space
into the surrounding areas.
And if you look on the on the side of this, we have the picture of the,
the Philharmonie in Paris, you know, very wonderful music hall,
quite recent, quite innovative design, wonderful sound inside it.
And then we have the other picture there
which is of an outdoor sound concert with all of the lights
and you can imagine all the sound going up into the sky.
So the control of sound from a wide range of the activities of our life
becomes quite difficult to control but we do have
ways and means of doing it.
Next slide please.
So if I just go back a little bit sound and human settlement,
it's an outcome, as I just said, of the functions of society,
we need to have industry, we need to have commerce,
we need to have transportation and with all of that comes sound.
So at some time, everyone who lives in the community
has been exposed to sound that's generated by others.
And, you know, once that sound reaches a level where it annoys
or disturbs us, that's when it's no longer considered as being acceptable.
And that's when we refer to it as noise.
So that's the changeover point between sound and noise.
Noise is basically that, that we don't wanna hear
because there's so much sound that we actually do want to hear.
Next slide, please.
To try and just give a little very simple quantitative measure for sound,
this thermometer style shows that, you know, we're talking about sound
as we're measuring it in the environment.
Down to as low as 10... very unlikely to ever get down to as low as 10 dB,
falling leaves are generally about 20 dB,
the slightest bit of wind or atmospherics around,
you're very unlikely to get anything below 25 dB, or 30 dB.
30 dB to 50, 60s kind of a sort of range of noise levels that
we are likely to experience in our house,
it can be a little bit louder in the office where we've got office machinery
and other actions being taken by other people in the office environment.
That's when we eventually get back to our offices, of course.
Inside a car, this is actually showing it at 90,
well actually inside a car is lower than that
but then what happens is that people turn up their sound systems inside the car,
so it ends up being around about that 80ish.
I think that particular spot there is a little bit higher.
There's been a lot of work done on reducing the interior noise
inside motor vehicles.
The stereo music there, around about 100,
that's kind of where if you go to a club or a pub or a venue,
where you've got some live music,
generally it's running at around about 95 to 100.
Unless it's considered as background noise,
in which case it would be much lower.
And then we get into the area of industrial noise
and the noise from individual tools, etc.
I'll just give a couple of points here and one is that,
around about 60 dBA is the sound of a voice if you're speaking to somebody
at about a metre.
So if the external noise is around about 60-65,
you can still communicate very well.
If the external noise is getting up to 80 or 90,
that's when you're having to really raise your voice
to speak in that environment, next slide please.
So if I talk about the upper limits for sound
in that we are very concerned about
ensuring that people in the workplace don't suffer from hearing damage
from their exposure to sound.
So the hearing damage can be measured and can be quantified.
So we can have audiometric checks
and the audiologist can identify if and whether there is
a loss in our perception of ability to hear sound.
Therefore, there are workplace practice limits,
and these are embedded in National and International Legislation in Australia.
And in Australia, this is that the equivalent energy level,
that's what this LAeq, 8 hours, so that's the average level effectively,
so the average level over 8 hours should not exceed 85 dB.
And at any one time at peak level, that's like saying something from a,
you know, an explosive, shot or something that has a very powerful
but very short duration pulse shouldn't exceed 140 dBC.
So that 85dBA, I'll talk mainly about that,
that's kind of the level if you're exposed to 85 dBA for a period of 8 hours,
then that's considered to be excess noise in the working environment.
Now you can be exposed to higher than 85 dBA,
but for shorter periods of time, it's an averaging process.
So what happens if the noise in a workplace is above 85 dBA,
averaged out over 8 hours then we try to do the best we can
in terms of implementing engineering controls at source
or between the source and where the worker is,
or using personal hearing protection as a last resort
and you'll see on construction sites,
where there are a lot of very noisy equipment.
It's also somewhat unpredictable about when
the equipment is going to be turning on and off.
You'll see that wearing personal hearing protection is one of the obligations
for the people who are in that environment or in that workplace I should say.
So we have a very wide range of engineering options
for reducing noise at source.
And there's a lot of improved design with modern products
and we've also got a great benefit from lightweight materials
carbon fibre the material.
So where we used to rely very much on mass and big, heavy enclosures,
we've now got a lot more interesting and innovative techniques.
Other factors that are really helping in terms of improving
the control of noise at the source is the development of computational techniques
that give us a better understanding of the energy flow
and also give opportunity for model testing before production.
In terms of the energy flow, some of those images,
the image on the far right-hand side there is representing how the sound
is actually distributing around that particular source.
So these are all aids that really help noise control engineers
to implement improved noise control options.
If I can have the next slide please.
For difficult problems we need new approaches
and as well as dealing with actually at the source itself
and looking at the energy flow,
there's development of completely new ways of doing things.
You know, look at it and think well, OK,
maybe there's a better way of doing this now,
which is not going to produce so much noise.
Some of the other techniques involve clever materials,
and one of them is microperforated panels are offering
opportunities for noise control, sonic crystals, sounds very gee-whiz stuff,
but that's absorbing, particularly very high absorption
of particular frequencies.
Metamaterials, so these are curious materials
that are neither metamaterial and they're not material.
Very, very interesting materials
and we're really still at the outset of applying those in acoustic environments.
And there's another emerging area which is acoustic black holes,
we all know about black holes out in astronomy.
In the case of acoustic black holes, it's kind of it's a very trendy name
to be given to something but essentially you design the material,
so that the energy in the vibration sort of disappears
to essentially nothing at a particular point,
but that involves tapering all of the metal surfaces down
or the beams down to a very narrow point.
So it is still a bit challenging,
but there are very interesting laboratory experiments showing
and it often doesn't take very long between a laboratory experiment
or a research project before
it actually becomes effectively useful in the real world in application,
and industries pick up those techniques.
Next slide please.
OK, so that's really looking at noise at the source.
Now if we think about the sound in the environment.
One of the big challenges that we have with sound in the environment
and establishing reasonable limits to the noise
is that there's a huge variation in individual response.
I mentioned that in the workplace environment,
we have, we can quantify the noise,
we can quantify the noise from demographic studies,
we can say well, if we can keep the noise below 85 dBA,
averaged over 8 hours, the majority of the population
will not show any adverse effects on their hearing.
For the environmental environment,
we have a much greater challenge
because it's difficult to actually measure it,
we need to consider aspects like health effects
and substantially the reaction to noise in our environment
is related to annoyance.
As I said before, when a sound becomes annoying,
that's when we refer to it as noise
and that's what the challenge for the environmental agencies
around the world not just in. Victoria but around the world is to
is to balance the need to do things in the environment
with the fact of trying to minimise the amount of annoyance
for the residents who are in that area.
If I can have the next slide please.
So let's think about noise from community activities.
This has been part of community life since the time of settlement.
Initially, the noise was generated by the activities of trades people.
There's historic reports where, you know,
middle ages and earlier, certain trades like stone chippers
and those sorts of known to be very noisy trades
have to actually move outside the city limits,
because they cause so much annoyance to the people inside the cities.
Transportation, back in in Roman days, they were complaining about wagon,
the sound of wagon wheels on the stone roads and the cobble roads
and there are even limits for
the hours that wagons could enter into the city
so that they wouldn't disturb the residents of the city.
The noise from community activities is increased
dramatically with the industrial revolution
that introduced mechanical machinery
which had the power to make a lot of noise
and then, as well, we have powered transportation.
Next slide please.
So as I say historically, the control measures were very similar
to what we would do today.
And if I just take the example of the road traffic noise,
the wagons were banned from the city streets at night.
So that was limited by time, time of day.
Then they tried to reduce the noise from the surface
by putting straw or dirt added to the road
in an attempt to achieve quieter road surfaces.
In more recent centuries, the type of road surface was looked at,
and even to the point of replacing cobblestones with wooden blocks
which were shown to not radiate as much noise
when the vehicles were passing over them.
Also, if you look at that, from the planning point of view,
the older cities were designed such that the higher quality housing
was located at greater distance from the roads
and it's certainly a greater distance from where
the potentially noisy activities of the work were taking place.
Next slide please.
So while annoying noise is more extensive in cities
and affects a greater number of people due to the population density,
but it also occurs in the rural areas and on the urban fringe
as an outcome of increased farming mechanisation.
And particularly nowadays because the machinery
that is used is quite powerful because it's meant to do a lot of tasks
as quickly and as efficiently as possible.
But also the focus is on the design of this equipment has been
on the efficiency of its operation.
So it's difficult for the farmer
while there are improvements being made all the time
in terms of the designs and the latest version of a
particular farming machine may well be quieter than the older one,
but it's very difficult for the farmers
to justify the high cost of continuing to update their machinery
mainly because, you know, they might only use it
for a certain part of the time of the year.
As well as that we've got the other innovations
in the rural industries
like on the image on the bottom right hand side there
with crop dusting.
So that then brings
the noise of the aircraft down very, very low over the farming areas.
Next slide please.
So the steps for managing noise in the community.
Basically, it comes down to first identifying
and acknowledging the problem,
then you need to establish a noise policy framework
to be able to manage this problem.
And within this noise policy framework,
you have to establish some noise limits.
And of course, I've just said before,
that's probably the hardest thing to do
because we're really only working on
annoyance reactions from the community.
Plus, the more recent information on health effects,
so the combination of those two aspects.
And then once you've done that,
then we have to monitor and assess compliance
as part of the enforcement process
because it's all very well to give
permission for a particular activity to take place that is,
and that the noise levels are not supposed to exceed a certain value
at the nearest residential property
but it's very important that that is monitored and checked
and making sure that that those
compliance levels are complied with.
Next slide, please.
So the concerns about noise in Australia,
it's not a new problem.
I'll just do a little diversion here.
I'm very grateful for my colleague in Argentina,
as a chance meeting at a conference
then led on to a bit of a discussion about things
and he's an acoustic historian
and he's been spending his time during his enforced
restriction in Argentina to delve into the
various libraries around the world that he's been able to access
and he's put up an amazing amount of information about
the reactions to community noise and the actions taken
about community noise in Australia.
So I'm very indebted to him for the next,
the information that's on the next couple of slides.
And he found out that there was a noise abatement league in Melbourne
and a noise abatement society in Sydney both founded back in 1928.
And the people who founded these organisations
were senior leaders of society,
and they urged actions to reduce noise.
Their comments are very,
very outstanding comments.
Noise is a nerve poison, unhealthy, unpleasant, irritating,
there's no need for excessive noise
which is made by the majority, sorry, made by the minority
to hurt and the harm of every one of the majority of the community.
Next slide, please.
And here we have some other comments that were made.
Now most of these recording comments from the leagues
are based on newspaper reports,
which were very, very particular
and were urging people to go along, to go to various meetings.
So at the outcome of these meetings were that,
they needed to have numerous letters from working,
women who claim that their sleep and that of their children
is continuously broken at night
by the hooting and roaring of motorcycles and motor cars.
You can think about this is back in the 1920s
so there weren't that many motorcycles and motor cars in the area.
They urged the head teachers of schools
to address the pupils on the subject and the influence of noise on health.
And here they were identifying already the potential for
damage from noise on health,
and they even began to talk about legal
control of noise on various activities,
because it was dangerous and injurious to health
and should be considered a nuisance
within the meaning of the. Public Health Act.
So these leagues had a number of medical people in them
and they were really being driven very much by public health
and their perception at that time
that it was important to control noise for the benefit of public health.
Next slide please.
Now, they even undertook some measurements
and the image on the left hand side there is
some measurements being made in Melbourne,
back in a roundabout 1930s and,
you know, we might think it's a bit challenging at the moment
to undertake measurements
and we've got a handheld sound level metre.
I used to think it was difficult when I had to
cart a tape recorder around as well but having to have all of that equipment
in order to make some measurements,
I mean, I really admire their efforts
and they demonstrated there,
the noise of individual vehicles going past showing the noise levels,
I'm not convinced that
their actual absolute values are correct,
but certainly the relative value showing how it's generally quiet
and then you're suddenly getting these short,
very high noise levels which definitely
is one of the aspects of increasing annoyance.
Next slide please.
These shows some measurements in the 1950s
when it was more feasible to have more portable equipment,
but even still, it was very clunky
and you can see the small microphone there
and one on the right he is trying to measure the noise from the refrigerator.
So there were a lot of efforts in the 1950s
once the instrumentation began to become more portable.
And that has some significance because it's really in the 1960s 70s
and then in the latter part of the 1900s that
the policy frameworks and acceptable noise levels
or the noise limits were established.
If I can have the next slide please.
So, the development of policy framework
really only started as far as we can find out from research at this stage,
the very first zoning noise ordinance
that actually specified maximum noise levels was back in 1957.
But even then it was a little bit of a notional ordinance in that it was
difficult to apply due to the limited capacity for
undertaking the measurements.
And so we jump forward into the 1960s like 1968,
Japan is believed to be the first country to introduce
noise provisions in legislation,
but those noise provisions were limited to workplace
and construction noise at that time.
In the 1970s, again, it was associated with
the development of more portable instrumentation
and more accurate ways and standards in terms of calibration etc.
And the in the 1970s, there was a big move to protect
all aspects of the environment and
most countries around the world established some form of
environmental legislation in the 1970s.
And that included aspects associated with noise.
Next slide, please.
So in Australia in the 1970s, each state developed its own policy,
harmonisation was encouraged at the federal level.
But for various regions, each state had slightly different approaches
and that still remains the case.
However, the common feature is that they're all based on the dBA
and that's a number that'll come up a number of times in the future,
but to define that the A is a filter
that is incorporated into the sound level metre
that has a similar frequency response to the human ear.
So, we can construct a sound level metre,
which has a very flat frequency response
but that's not the way our human ear hears the sound,
so the A weighting is a filter that's put into the measurement chain
to ensure that the numbers that we get out of the measurement process are
somewhat similar to and relevant to the way we're hearing sound.
Next slide please.
So if we then move on into the 1990s,
nationally and internationally, environmental management
began to move to focus more on the natural environment,
clean air, clean water, ensuring biodiversity.
And in part, this was, because it was well understood
that bad air and bad water would lead to health effects
but environmental noise was considered only to be annoyance.
So we had the noise control in the workplace
which was to protect against damaging noise
but the management of environmental noise
began to become very much lower down the priority chain
because the focus was on making sure that the
air and the water were kept nice and clean
because it was well known that they would lead to health effects.
So it was acknowledged that there was a need to quantify health effects
from noise below the hearing damage level.
And this is the point where the World Health Organisation
actually began to become involved
in sponsoring and supporting various investigations.
Next slide please.
And the first document that they came out with which was
summarising the health effects of noise was back in 1999,
and it was the World Health Organisation guidelines for community noise.
And they identified in the, right up there in the introductory sections
that they considered the potential health effects of community noise
includes these effects on hearing, sleep disturbance,
cardiovascular effects, performance reduction and annoyance responses.
I've highlighted in red there, the cardiovascular effects because
that will keep coming up again, in terms of the health effects of noise,
the outcome of studies on the health effects of noise.
It's important to understand that these studies
were mainly undertaken by countries within the European Union.
And in order to undertake studies on measuring health effects
you have to have large cohort groups
that are exposed to much the same noise
to see whether or not there really is effect of the noise.
So there is somewhat of a bias
in all of these studies to those people that are living in
more highly populated cities
because that was really where the,
most of these studies, many of these studies were undertaken.
Not all but many of them.
Next slide, please.
So having, having achieved that, that outcome that report,
the European Union became very active in this space.
and they introduced a directive in 2002.
And this is associated with environmental noise,
and they're saying it's part of the community policy
to achieve a high level of health and environmental protection
and one of the objectives is to be protection against noise,
and they refer to some of their earlier documentation.
And they actually said it's one of the
main environmental problems in Europe.
So this really gave a big impetus for more studies on really
delving into the health effects of noise and the,
providing good guidance, improved guidance
on what would be acceptable noise levels
for noise in the environmental and community areas.
And the significance of the EU directive
is that this was a directive to all the member countries of the EU,
that they needed to do something about this.
One of the requirements was they had to do maps, noise maps around cities
and while the noise maps are really just monitoring the existing noise
it's putting a focus on the importance of noise
and assisting a broad range of specialists,
including the planners and really reinforcing the importance of noise,
the fact that we can measure it
that it varies from one part of a city to another and,
you know, we need to really consider this in terms of planning objectives,
as well as environmental noise policies.
Next slide, please.
So, just talking a little bit more about the health effects of noise,
as I mentioned, the evidence of health effects
is mainly from European studies.
There were major multi-country studies supported by the European Union.
So a lot of these studies were done in,
well there were some done in the 1990s
but there have been a lot more over the last
two decades of this century.
There's similar concerns around the rest of the world
but it's really been the impetus of the WHO and the EU
that has really kept this going because
other studies around the world are there,
but they're, they're being done by individual agencies
and it's really hard, it's really important
that the EU has had such an important role and WHO
to bring all of these different studies together
and analyse them and come up with some recommendations.
Next slide, please.
So we have in 2009,
the WHO guidelines were introduced for noise guidelines for Europe.
Now at this point, they really acknowledged the fact that
the data they had was really relevant to Europe
so they specified that these guidelines were applicable to Europe
and they got these levels here in terms of a target noise level
and an interim target,
acknowledging that it's going to be really hard
to have an average noise level
over the nighttime period at 40 dB
but they thought that it was reasonable to
have as an interim target 55 dB over the nighttime.
Next slide please.
Then we come up to the. WHO burden of disease.
This was another report trying to identify,
well OK, if there are these health effects,
cardiovascular effects, etc, etc.
How are these affecting the lifespan of people
or are these affecting the lifespan of people.
And so one of the studies was the disability adjusted life years,
and this study indicates that the,
the number of years lost for environmental noise
in Western European countries.
And you can see those numbers there,
they're really amazing like 61,000 for heart disease,
45,000, cognitive impairment of children,
903,000 for sleep disturbance, etc.
So, these are really sort of emphasising the fact that,
that we do need to be very careful about noise in the community
because noise has these health effects.
If it affects the health then it affects the happy life,
healthy lifestyle as well.
Next slide, please.
So then there was another,
because it's been a quite a few studies done
in the three decades from the 1990s, 2000, 2010,
there was a major evaluation of health effects
and this is involved a review of major studies to try and actually look across
all the different studies that have been undertaken,
try and evaluate the strengths of the outcomes from the different studies.
Some studies were made on very small groups,
other studies were made on very, very large groups.
So trying to pull all of this together in a meta analysis of all the findings.
And that then led to some more further guidelines
that were released by the WHO
on the different types of environmental noise sources.
And then linking that across to the likely health effects
from the evidence of all of this big meta analysis
of all these different studies that had been undertaken.
Next slide please.
And that met in 2018, to the WHO
environmental noise guidelines for Europe.
So these are based on the Lden.. Now, I need to explain that
that's a day evening and night average value
so it's doesn't mean that road traffic noise
should not exceed 53 dBA,
you can have it a bit higher during the day
and then a bit lower in the evening
and then it'll go lower at the end of the
very late at night when the traffic,
so it's kind of averaging it out over the entire period.
As well as that they have a nighttime value
that would just apply the average value over the night time.
So I do emphasise again that these numbers don't mean that
the noise level should not exceed that number at any time during the day,
it's an averaged venue.
So their recommendations range from a 53 dBA
over the 24 hour period, the day evening and night
down to road traffic noise down to 45 dBA
associated with aircraft noise
and similarly the L nighttime values
are lower than the average ones over the entire day.
They also put one in for wind turbine noise.
And because that was so low at 45 dBA.
They didn't put another one in for the night time.
Next slide please.
So what were the main health effects that they indicated
if the noise levels were much above
those values that they were giving as guidelines.
And you'll see that heart disease comes up on most of these.
Ischaemic heart disease, annoyance, sleep disturbance,
potential incidence of stroke and diabetes.
Were all indicated from studies associated with road traffic noise.
Railway noise were predominantly annoyance and sleep disturbance.
Aircraft noise was the annoyance, there was some concern about reading
and oral comprehension, sleep disturbance.
And this one I think is interesting, potentially changing waist circumference.
I don't quite understand that one.
But anyway, unless the people just felt
that they didn't wanna go out walking and exercising
because of the concern about overflying aircraft.
However, that one popped up in
as a reasonably good evidence for that particular outcome,
health effect from people who were exposed to aircraft noise.
And with wind turbine,
the only findings they had were related to annoyance.
Next slide please.
Leisure noise they dealt with in a slightly different way.
And they really base that one on the effects of hearing damage.
Primarily because it's well known that there are a lot of
leisure noises that are very loud.
That are well above 85 dB, well above workplace noise limits,
well above the limits that,
if their people are exposed to them for long periods of time,
they would be likely to have some form of hearing damage.
The problem with this one is trying it look at a yearly average.
So it's not just a daily average that I've been talking about.
It's the yearly average of 70.
So it's a very difficult one to deal with and it's probably better
for the, WHO is now continuing to work with an App
to indicate music noise exposure.
which will be a much better way of dealing with it
than having a single number guideline.
But the main message from this
is that, that leisure noise,
even though you might want to, your enjoying the leisure
and you might want to be active in it.
That can still have the same effect on your hearing.
And it still needs control, just like any other aspect of noise.
Next slide please.
Around about the time that. WHO were doing this
review of all the different studies
enHEALTH in Australia was also undertaking a study
where they were actually reviewing a whole lot of major studies.
As I've said very similar to the WHO.
And from looking at these studies as a,
you know, completely independent of the WHO review.
They found, again, there was sufficient evidence for environmental noise
and sleep disturbance and cardiovascular disease.
And that there should be health based limits for residential lands.
And the recommendations were not that dissimilar, slightly different metrics.
So they're looking at equivalent energy just over the nighttime
and then the daytime one.
So slightly different metrics
and that's one of the confusing things with
a lot of the environmental noise limits
is different jurisdictions use different metrics.
But in most cases, they all come in very similar to each other.
If you do the adjustments to allow for this metric versus another metric.
Next slide please.
OK, so assessing the noise.
As I mentioned, awhile ago it's essential to assess, monitor the noise
to ensure compliance.
There have been great advances in technical aspects of noise measurement.
The days of having to carry a heavy tape recorder around,
like that person there on the left hand side,
has, have well and truly gone.
And we have handheld sound level metres that have got the capacity of,
you know, what used to be big laboratory based instrumentation.
We've also got loggers that can be left out on the site
for long periods of time and therefore monitor the noise
over weeks or months.
We also have more complicated arrays that can assist with identifying
the direction of noise.
Because simple monitors will just pick up all the noise in the area.
And there are many circumstances where it's important to know
from which direction the noise is predominantly coming,
so that the noise control measures can be applied in that direction.
Next slide please.
So as I said, even a basic sound level metre
has the processing and storage capacity to provide a wide range of metrics.
Additional features such as audio file storage and transmission back to base,
for remote monitoring really assist,
you don't really need to have the storage on location.
You can just have a sensor on location and transmit the data
to the cloud for storage.
And this is opening up a lot of opportunities
because sensors alone are cheap.
And so you can have lots of them distributed around.
You don't have to have a very expensive sound level metre with a data analyser
with the heavy battery and that on location.
You can just have a lot of these small sensors scattered around
with all the information going up to the cloud
and the analysis being done subsequently.
Next slide please.
So that means we can have a lot more information on area wide noise levels.
Cities can install noise sensors with other environmental sensors.
And that can give extensive information on variation and levels.
They can be used for noise assessment.
They can also be used for soundscape analysis.
Soundscape is actually looking at the whole sound environment in certain areas.
And, this is an important area of study
to make sure that we're balancing the sounds.
That the sounds in different areas are,
are not just not annoying but are pleasant to the people who are in those areas.
The other thing that you can do
when you've got these sensors and sending information up to the cloud
is to involve citizen-science
for reactions to the sound at the time.
And you can even use mobile phones with limitations
because of course, we know the microphone on the mobile phone may not be
calibrated properly, but relatively we can still look at the data
that might be coming from those.
And there's quite a lot of studies being undertaken around the world
with some various websites where you can plot in where you are
and what the noise levels are
and what your reaction to those noise levels are.
Next slide please.
So this is a just a graphic for a concept of a city array.
You have all these sensors that are
then sending information to a central base.
And, that allows the city council,
or the research or the university if it's doing research
or whatever organisation is assessing the information
to really keep a close watch and monitor the noise
and much more rapidly identify where there are
spots with higher noise level.
And then look at those and see what can be done to reduce those noises.
Next slide please.
The EU has been sponsoring a number of such initiatives.
And like the Santander, Spain is one such initiative.
They've got Internet of Things in the context of a smart city.
They got 740 sensors around.
They include carbon monoxide sensors, light intensity,
noise, temperature, car presences, plus mobile sensors on vehicles etc.
So they're really getting a heap of data
about noise, the way the noise varies,
the types of noise in different parts of the city.
Next slide please.
There's another study in Pisa.
These are just two examples.
There are quite a lot of these studies around European cities
and also in some of the Asian cities.
They are developing these as well.
This one is based on noise sensors located on private houses.
So they've got the noise sensor,
it's just a small sensor attached to the balcony
and the information is then being plotted to monitor the noise over time
and season and activity.
Next slide please.
Now, of course, these sorts of sensors and data
has become very interesting to people working in acoustics
because of the change in the operation of a city
before and after COVID restrictions.
And I'm grateful here to two consultants, who shared some charts that they had.
Where they had a noise logger on location before
and then during the time of the restrictions.
So in this one, the position was in a
industrial area but there was quite a lot of transportation around.
And you can see the green line there is the noise level that would be typically
be very low during the nighttime then rise during the day.
then it dropped off the next evening and then rose,
not quite so high the second day.
And that, so that represents two days worth of data.
The blue line is in that same area of the city
after the restrictions had been introduced.
And the first line shows there's about a 5 to 6 dB reduction
due to the reduction in the traffic flow in the area.
On the second day, the reduction is again, around about 5 to 6 dB,
but then there was this little peak
towards the late afternoon of the second day.
And when the noise level was almost as loud as the pre-COVID time.
And as I mentioned, this was in an industrial area
and it turned out that the nearby buildings
were having or factory industry that was there,
was having a substantial amount of delivery activity at that time.
So the noise, the local noise increased
even though the more global noise in the area was lower.
Sometimes you will get these increases in local noise.
Next slide please.
This one's a very hard one to understand.
But this is again from another consultant who had a logger on site
monitoring noise from a major roadway.
The blue dots show a whole lot of noise level data
over a number of days and a number of weeks.
And the orange dots show the post COVID ones.
And you can see that the post COVID ones again,
are reduced by about 5 to 6 dB.
And that seems to be coming up quite broadly around the world.
There's lots of people around the world who are doing this.
And there's going to be a lot of publications
investigating and reporting on and assessing
the pre and post-COVID restrictions noise level data.
And it will provide a wealth of information for the environmental agencies
when they're trying to establish reasonable
and feasible compliance noise limits for various activities.
Next slide please.
In terms of broad monitoring on a regular basis,
the nearest that we've got in Australia
is the aircraft noise and flight path monitoring system
which is available to the general public to access.
And this is Webtrack.
You can access it from air services site.
It has live with just a very short time lag live data.
It's well established, it's used for various forms of enforcement.
It's also used for communication.
So anybody, the important thing about this
is that it's accessible to the whole community.
You don't have to be in the airline industry,
you don't have to be in air services to look at this.
And I did do a comparative one.
The chart, that's a bit to the left where you can see a lot of blue planes
and red planes entering and departing from Sydney Airport
was obviously pre-COVID.
And the one on the right, I just did a download at 1600 on the 31 August.
And you can see there's only one plane in the area.
The ones out around Blacktown,
are some helicopter operations in that area.
But the little yellow dots are the noise monitors
that are part of the monitoring system around the airport.
And again the numbers that are appearing there,
of course, significantly less than the numbers that were appearing
prior to that to the COVID restrictions.
Next slide, please.
With all of this monitoring and getting a lot of data, it's very tedious
to try and identify exactly what's causing the spikes, the high noise levels.
So automatic source identification is one of the goals.
It's an important aspect because it's the only way
that we're going to be able to dive into this big data.
So when one noise is dominant, it's reasonably easy to define the rules,
for example, the noise monitors around the airport.
But when, and you also get additional information about flight path tracking,
so you can definitely identify that high noise levels rate
because there was an aircraft within the area at that particular time.
But when there are multiple noise sources or the target noise
is very close to the ambient noise, it's a lot more challenging.
Next slide please.
So feature extraction.
Our brains can do this almost instantaneously.
We're really good at doing that.
But it's really hard to do it and there's a lot of work going on
in this area to try and extract that information out of the broader noise.
And the progress is generally going in parallel with auralisation,
which is making a sound from the model data,
as well as Computational. Auditory Scene Analysis.
So this is something that's still a work in progress.
It's not fully reliable at this stage, but it's certainly something that
will be an outcome in the next couple of years.
Next slide please.
So the basic requirement for establishing environmental noise goals
is to achieve a low risk of health effects.
The WHO studies and outcomes can be used as guide,
but we also need to consider what a community considers acceptable.
The challenge is the reaction to environmental noise
and annoyance varies very much across the community.
Next slide.
So we have to consider community response
and what are the actual needs of the community.
Demonstrate that annoyance is complex
and includes attitudes, visual aesthetics familiarity with the environment.
Supported by complaint statistics is something else
that feeds into community response.
But we generally get somewhat of an inconsistent outcome
because although the levels of individual aircraft have been reducing,
and the noise contours are moving close to the airport.
The complaints should be reducing, but that's not happening.
So you've got to offset that with the fact that
the community is more aware of how to go about complaining about noise.
So you're actually getting more, more complaints coming in
into the various organisations that are tracking that.
Next slide please.
This really highlights the dose-response relationship.
The variability across the community in that,
along the horizontal axis, we've got noise level.
And on the vertical axis, we've got the percentage,
highly annoyed by that noise.
And the different images there relate to, oh sorry,
the different lines there relate to different types of noise sources.
The blue one is the aircraft one.
So people are very highly annoyed by noise from aircraft
as opposed to the same level of noise from road
and even less annoyed by the same level of noise from trains.
So there's a subjective element in,
very strong subjective element in relation to dose-response relationships
and trying to use that as a measure or an indicator
in the setting of compliance levels and establishing limits to noise.
Next slide please.
So developing noise policy is not just noise level and character alone.
All your data or knowing what sort of noise you're dealing with.
You gotta consider the broader aspects
that have influence of perception to the community.
And understand the importance of clarity of information to the community.
Next slide.
And this chart here,. I'm sorry, probably don't,
may not be able to see the detail of it.
But it's really highlighting the fact that it's like an onion,
you've got annoyance in the centre,
but you've got so many factors that are going to feed into that.
The next circle around is the satisfaction trust.
Do you feel that it's fair?
Do you feel that you've got some control?
Is there somebody you can ring if you're really annoyed by the noise?
And the next one around, the next shell of the onion
is listening and communication transparency.
Do you know what's happening?
Have you been told that there's going to be a noisy event happening
and it's only gonna go for a couple of hours.
And that you've had the opportunity to have community forums
and you've had real communication with organisations.
So, all of those aspects are very important
in terms of the way people will react to the noise.
How annoying they will find it.
And also, you know, if they're not annoyed by it, they're less stressed by it
and we would like to think that they would not have such severe
health effects consequently.
Next slide please.
So sound and noise are part of society.
We need to maintain sound in its most desirable form.
The sound of music, the sound of nature, speech and hearing.
We need to understand soundscapes.
You know, what sort of sounds do we actually like to hear?
We do know about hearing damage
and beginning to know more about the health effects of noise.
And technology provides for exciting opportunities
for even greater understanding of noise.
Next slide.
And that then leads me on to the International Year of Sound 2020.
It was an initiative of the. International Commission for Acoustics.
To really highlight the importance of sound in so many aspects.
I've been primarily focusing on environmental noise.
But sound has a very important aspect in in so many certain parts of our,
of our world, of our scientific endeavours.
You know, underwater sound, we've got atmospheric sound.
It's used very, very widely.
And so that was the goal of the Year of Sound.
We managed to have the opening in Paris at the end of February.
And then of course, everything, and there were huge number of activities
planned for throughout the year,
to try and, outreach activities.
To try and highlight the importance of sound throughout the year 2020.
And of course, then COVID hit
and so all of those activities that involved individuals meeting together
were then stopped.
However, the momentum for an. International Year of Sound hasn't stopped.
And if I can have the next slide, please.
This just refers to the. UNESCO resolution in 2017.
So even UNESCO said that the sound environment is so important
that it shapes our personal and collective behaviour.
Next slide please.
So the goals of the. International Year of Sound, as I've said,
are to improve the public understanding,
to highlight the importance and use and benefits of sound
while controlling unwanted sound.
To raise the understanding of those in society
with hearing or speech impairment.
And to promote the importance of protecting hearing.
Next one please.
So the International Year of Sound is now continuing into 2021.
So it's gonna be two year celebration instead of a one year celebration.
But a lot of that effort that went into
planning for various outreach activities
has actually been pivoted to now planning for and creating
a lot of resources.
That will actually be a legacy of the Year of Sound 2020, 2021.
And I'm just highlighting the website there
because the website has a lot of, you can see a lot of tabs.
So it's got an event calendar.
Unfortunately, a lot of those have been postponed to the next year.
But it's also got a lot of information, a lot of resources.
There's a video on the importance of sound.
The Sound in Our World
that was sponsored by International. Institute of Noise Control Engineering.
So it talks about different examples of noise control.
There's a lot of other web information, technical information, etc.
Web links, etc.
So, and downloadable information.
That's all for free at this stage.
So we, you know, I do suggest
that if anyone's interested in this,
that you have a look at that website
and there's even some Australian ones,
like there was a group that were measuring the sound of the rivers
as an indication of environmental measures,
and we're going to use that in conservation measures.
And so they've shared their information
on the sound that they measured all the way along.
I think it was the Murray Darling,. I have to check that but
one of the rivers.
So there's a lot of very interesting, innovative ideas
and information that can be used by,
can be accessed and also some of it is actually educational,
which can be used by people who need to,
who would like to supplement whatever information they already have.
Next slide, please.
OK, well, thank you very much for your, your attention
and I see we move over now to the Q&A.

ANDREA HINWOOD: (INAUDIBLE)
Let's move on to the Q&A,
and then I can ask everyone to virtually be clapping
and thanking Marion for her presentation at the end.
But let's move to Q&A.
And in fact, I have a question, but actually feeds into this first question here,
which is how does the EPA see their role changing or not
in the regulation and policy for road and rail noise?
And will it change in relation to amendments to the EP Act?
So Marion, I'm not sure whether you're aware,
but in July 2021, we will have the new general environmental duty
and what that means is that all of us
and in particular duty holders and that includes those who,
you know, those who have cars,
and those who manage roadways and transport,
will have an obligation to manage their emissions
and discharges etc, including noise,
i.e, they must do what is reasonably practicable
to ensure that the emission of noise in this case,
you know, that they take that seriously
and that they have done everything that they can.
So, in terms of our role, you provide advice
into the road and rail sectors as people would be aware,
but under the general environmental duty
that the onus goes on to the duty holder
to ensure they are doing the right thing.
And I guess where my question was going to Marion after her presentation was,
when you look at the new technologies
and the new materials being developed,
do you think that it's going to substantially change
the noise in say, the road and transport sectors,
or is that some way away, like, how we're going in that space
and how long before we might see some significant improvements?

MARION BURGESS: Well, certainly there are the,
I think it's not going to be a big step.
What happens is that the new models of vehicles
are made with the modern technology.
And there's certainly been big improvements
in a lot of the vehicles on the other hand with the trucks,
of course some of the very, very big trucks
that we have in Australia, like the big B-Doubles and that,
have such powerful engines.
You've got a real challenge there,
but certainly the vehicles that travel around
in the residential areas are,
the potential is great there and the new,
each model is a bit quieter than the last model
and people would know if you go to buy a car.
Just a passenger car, the passenger cars,
the output noise from passenger cars,
is gradually reducing compared to what it was back in the 1990s say,
but the problem is that it takes a long time
for this change to be implemented throughout the entire vehicle fleet.
So it's going to be a bit more incremental,
so in terms of the individual vehicles,
then yes, the noise level for those is gradually reducing.
The other factor is the tyre-roadway interaction,
and there are efforts there to have better
and cleverer road surfaces.
And so there are big improvements there.
And in fact, there are predictions that into the future,
the noise, the predominant noise
will be the tyre-roadway interaction
and the aerodynamic noise around the vehicle.
And both of those are manageable as well.
So you know, there is a lot of work going on in all of those areas
to achieve this, yes.

ANDREA HINWOOD: Interesting.
Our next two questions are related to the health effects of noise.
And I'm not sure whether you can answer this, this question,
I can probably provide some answer,
but it's in terms of how noise affects cardiovascular disease
and how it affects metabolism and weight.
And I'll also like to say that noise and air pollution go together.
And air pollution has also been related to cardiovascular disease,
which increases your risk of diabetes, etc.
And of course, there are a range of concerns on that.
But I wonder if, if you're able to elaborate
a bit more about how noise causes these effects.
We'll take these questions on notice
and we'll provide a response later.

MARION BURGESS: Well, probably be good to take it on notice
and provide a bit more of response,
'cause I'm not a health expert by any means.
But I believe that the linkage is really from the stress,
the fact that the noise leads to annoyance which leads to stress.
And I think we all know that if we get stressed,
even with a healthy heart, it will start pumping away,
so it has effects on your heart.
So I believe that's the linkage across and similarly,
that then continues on into the diabetes aspect in that people,
you know, as soon as you've got a stress on your body,
and you've got a potential for diabetes,
you stress your body in one way,
and it'll show the effects in other parts of the body,
is probably the best I could say.

ANDREA HINWOOD: And I actually listened to the
International Society for Environmental. Epidemiology, was on last week,
and I listened to some of their sessions on noise.
And they've been actually looking at the combined effect
on a range of health outcomes,
where they're considering air pollution and noise in joint models.
And noise is still coming out on its own,
affecting cardiovascular outcomes.
So we'll certainly get back to you with a better response than that James.

MARION BURGESS: If I can just add another comment too,
of course, the effect of noise
is often related to sleep disturbance as well.
Sleep disturbance can then have,
is just a different sort of stress,
you're not, you're not awake
and considering that you're annoyed by the noise,
but you are suddenly awakened, so you don't get the sleep.
And so all of that has an effect on your body.

ANDREA HINWOOD: So the next question is about wind turbines,
causing impact on health, not just annoyance,
as shown in your graphs at the low dB levels,
I wonder if he wants to make a comment on that.

MARION BURGESS: Again, this is something that's a very topical issue,
it's an area where there have been a lot of claims
about other types of health effects from,
from wind turbine noise.
I believe that there are a number of studies
and in fact, there's a very, very recent study,
so I think it would be better to take that one on notice,
because up until recently there has been,
my understanding is that there's
very little strong evidence of that relationship.
At the very low freq... there's a low, there's a,
there's a concern about low-frequency noise effects
that are right down in the very, very low-frequencies.
And maybe that's what that question is relating to,
but we can refer back,
there's been a study in Australia,
which there is a report
and I can refer them back to that report.

ANDREA HINWOOD: I was going to make a comment,
the National Health and Medical Research Council
has put out some advice on that.
And they do cite a study,
which is essentially saying there's no consistent,
no consistency in the studies
in terms of the effects on health,
but that they need much more robust study designs
to actually answer the question.
So if my reading of the NHMRC outcomes
and the expert panel is right,
that's essentially what they're saying.

MARION BURGESS: Thank you, Andrea.
That was what I had in the back of my mind.
But I'm really pleased that you're endorsing that.
And can I just add that one of the reasons why,
there's need to have more investigation
is that this, it comes back the demographics,
the number of people.
You need, a large cohort of people
that are exposed to the same sort of noise,
or the same sort of low-frequency sound
or whatever it may be,
in order to be able to then link it across
and definitively show that you've got health effects showing up.

ANDREA HINWOOD: So this is a nice question
that I probably shouldn't answer, because I'm biased,
'cause I come from Victoria.
So Marion, how does Victorian regulation of noise,
and you can be honest, compare with other states
or countries, who's doing it well,
and what can we do better?

MARION BURGESS: I'm really pleased with that question, because I haven't...

ANDREA HINWOOD: Yeah it's a good question.

MARION BURGESS: ..haven't thought recently,
there are some years ago,
we did a review of the different states.
And really the outcome of the different policies across the states,
the outcome at that time
when I say some years ago was,
you know, over a decade ago,
they, the outcome really was
that they were all about the same in terms of their noise policy,
the goal, even though the numbers and the metrics
were a little bit different,
the actual goals were much of a muchness,
and there wasn't a huge difference between any of them.
But I know that the states have been modifying
and updating and improving their policies,
since that study was done.
And thank you for raising that,
because I think it will be interesting to do it again now in 2020.
And this would be a very good time to do a review of the,
the noise policy around Australia and just really, really check it.
One of the challenges that I can remember
when we did the previous one was that,
you know, it takes a little while to do any of these studies
and to write it all up.
And we're just about writing it up
and then bang, there's another policy, a different state,
you know, is introducing a slightly different policy in this area.
So, so it was a, you have to sort of set a date and say,
we're not going to look at anything after this state.

ANDREA HINWOOD: So we have, we do have some new
regulations coming in place.
And as I said, the general environmental duty,
which is quite a different focus,
because it puts the onus on the duty holder
to manage their own noise.
So it's gonna be interesting in, in any comparison I think.

MARION BURGESS: Yes.

ANDREA HINWOOD: So in terms of this question,
occasional noise is not very disturbing,
compared with motorway noise.
And the noise barriers don't seem to have evolved much in Australia.
Do we know if there's much progress in that field?
It's a good question.

MARION BURGESS: Yes, there's quite a bit of progress
in the field of traffic noise barriers,
mainly in trying to apply new clever techniques to,
on the one hand, to minimise the profile of the barriers
and on the other hand to try and have
the effective height of the barrier,
greater than the physical height of the barrier.
What I mean there is if you can do clever things
on the top of the barrier,
you can get a reduction in noise
which would normally be achieved by a higher barrier.
So you keep the barrier a bit lower,
but you do clever things on the top
to have the waves offsetting each other, etc.
But, and you can try and have sound absorbing material
at the higher sections of the barriers
as well to avoid bounce back between, between the barriers.
But, but yes, there are improvements there.
But to be honest,. I don't think there's going to be
a very dramatic change in the near future.
It's a matter of improving
and optimising the barriers really, that's what it comes down to.

ANDREA HINWOOD: So the next question is, what your thoughts are
on including background ambient noise measurements,
in setting noise limits.
Despite it being slightly more complex,
Tim is interested in your views
on whether it's more robust for setting appropriate limits,
particularly for industry.
And I guess what he's getting at is that,
cumulative noise aspect in terms of setting limits that you take,
when I'm more used to air sheds,
let's call a noise shed for argument's sake,
or acoustic environments, yeah.

MARION BURGESS: Yes well, I mean, some of the legislation
around the country and policy around the country does do this.
It compares the noise level from the offending noise
with whatever is the background noise in the area
and uses that as a measure,
as opposed to a planning approach.
The challenge with using a background noise
as the question that Tim has raised
is that you have to measure twice,
you have to measure the background noise
when the offending noise is not there.
Then you have to measure when the offending noise is there
and you can't just go and measure it,
like 2:00 on a Monday,
because you have to actually average it out.
The noise, even during the daytime
or the noise in the evening or the noise at nighttime
is going to vary.
So you need to make a reasonable estimation
of what that background noise level is in different time zones.
So it does become a bit more complicated
and particularly in industrial environments
where you might have a number of other noisy activities
that of themselves are sitting there in the background,
but they're actually raising the background a little bit,
and then you measure the background
with them operating before the new person comes in,
you know, makes it a little bit difficult
to see whether there is fairness in that situation.
On the other hand, if you haven't based on a land use method
where you say the noise level for this area
should not exceed this value,
this is a reasonable value for this area.
You will always have a bit of a challenge on the boundaries
between the two different zones.
So if you got residential, next to a commercial,
you have to have special treatments
for the people that are right on that periphery boundary.
So both methods have their challenges,
whether one is better than the other,
it really, you know, I wouldn't really like
to make a preference for one or the other.

ANDREA HINWOOD: OK, thanks for that.
And Namiko has asked, what's the difference between acoustic black holes and noise cancellation?

MARION BURGESS: OK, noise cancellation is when you actually create a noise
that's 180 degrees out of phase
with the noise that you're dealing with.
It's quite difficult to do it with a broadband noise.
It's much more effective if you've got a lower frequency sound.
So as soon as you, when you've got lower frequencies,
you've got longer wavelength,
so it's more feasible to, to get this matching 180 degree
out of phase matching so that the result is almost zero.
It's never zero, but at the higher
frequencies it's very hard to get this matching,
'cause the wavelength is only tiny.
So in a noise-cancelling application,
you're creating a noise to offset the existing noise
that's in the area.
In the, in the black hole, the acoustic black hole,
you're trying to create a, it's related to the structure-borne sounds,
so you are trying to make sure that the vibration
that's set up in a structure, kind of disappears down a hole
and doesn't radiate sound.
So it's quite a different approach.

ANDREA HINWOOD: OK, thank you.
John has made an observation about the correlation
between the length of time and noise source has been around,
and its acceptance or tolerance.
And he's referring to the graphs,
that showed train noise is most accepted,
then car noise, then aircraft and finally wind turbines noise
and he thinks that mirrors,
when those sounds were introduced to society,
and whether you had any comment on that?

MARION BURGESS: Well, indeed, I think there is a relationship there.
And there's also, but it's not a just a simple one
in terms of when they were introduced.
There are those other factors that we talked about.
Train noise is a very interesting one
in that trains can be quite loud.
And certainly if there are problems in rural areas with freight trains,
because the surrounding areas are very quiet,
freight trains are carrying, whole trains,
and that they're carrying large amounts of coal,
they've got quite big in engines,
they're going for long periods of time.
But in residential areas, the issue of trains is very reliable,
it's predictable, because they've go to a train timetable,
the length of each passing train is very similar.
Whereas for road traffic noise,
you don't know whether you're gonna get a platoon of noisy cars
or trucks or whatever.
So there's a lot more variability.
So, all of these factors blend into it.
So there's a lot of this psychology associated with their reaction
to the sound in terms of the way people
will consider it to be an unacceptable or an acceptable noise.
So I think, sorry to answer that, that was a long answer,
but I don't think it's only time,
I think he's, I think he is right.
Yes, that is one of the many factors that go into it.

ANDREA HINWOOD: OK, and there's a question here.
What do you think are the primary obstacles
to reducing noise levels in the environment currently?
Given we know we have these relationships
with, you know, health and environmental outcomes,
what are some of the obstacles?

MARION BURGESS: Well, I guess it depends upon
where do you, where do you start first?
You know, I think we're already doing a lot in this respect
in that we're already... thank you.
We are already... my husband just brought in a chocolate biscuit for me, (LAUGHTER)
I was fading.
We are already making inroads into reduction of noise,
in each one of them.
So I don't think that there's a primary obstacle.
If I look at it more globally,
rather than thinking about noise source by noise source,
I look at it more globally,
I think probably the enforcement
is probably one of the critical things that's very important.
And that's one of the important roles of the EPA,
is not just to establish policy and establish compliance limits
or noise levels or whatever,
but also to make sure that these are being implemented
in a reasonable and a fair way.
The worst thing is to set the limit so low that industry
and commerce can't, and recreation can't be in place.
So I think that the EPA has a very challenging role
in trying to set these reasonable levels,
but the enforcement is probably
just equally as important.

ANDREA HINWOOD: Look, I think that's a terrific place to actually finish this session.
I have learned so much about noise,
I kind of knew some things about it.
But I'm particularly interested in the black holes
on some of that new technology.
And I think the other thing that we're doing here in Victoria,
we're actually doing some research
which has been stymied by COVID-19,
in developing a noise map for Melbourne.
And so, we did have some work going on,
where we were going out and doing some additional noise monitoring,
that's put on hold at the moment.
We're hoping to develop one of those noise maps
which will also help us and aid in decision making
and working out where priority areas might be for attention.
But Marion, I know everyone listening
will be thanking you greatly,
hopefully they're all clapping to you
as I am right now as we would in a normal setting.
It's been most valuable.
Thank you very much for your time
and I think perhaps we'll have to have another of these sessions
given that we'll have the year of acoustics
going into 2021 or sound going into 2021.
Maybe it's a time to continue it for Australia as well.
And thank you to everyone listening today,
for spending time listening to this particular topic.
Our next environmental seminar series,
is actually coming up in October.
So please keep an eye out for that.
and wish you all well and for those of you in,
those of you in Victoria, under stage four restrictions,
stay safe and stay strong.
And we'll see you next time. Thank you.