Categories
Asia Noise News

Coronavirus Lockdown Gives Animals A Rare Break from Noise Pollution

The COVID-19 lockdown could become an unprecedented natural experiment in noise pollution. Some of the world’s most vocal animals — birds and whales — might already be benefiting from a quieter environment.

While a drop in transportation during the coronavirus lockdowns has led to lower pollution levels across the world, the slowdown in traffic has also lowered another big polluter: noise.

According to the World Health Organization (WHO), noise pollution affects over 100 million people across Europe and, in Western Europe alone, road traffic accounts for premature deaths equivalent to the loss of roughly “1.6 million healthy years of life.” 

Take the disturbance to human health out of the equation, and noise remains a big source of pollution for the other inhabitants of the planet as well, namely, animals. 

But how much have animals in countries on lockdown really benefited from the drop in noise levels? Turns out, that’s a very difficult question to answer.

Birds will benefit the most

Birds — by far the most visible animals found in cities, and the most vocal — stand to be among the biggest beneficiaries of quieter streets and parks. 

The signals birds send each other through song is a means of survival. Without the ability to sing, hear and be heard, birds would have a difficult time finding a mate or defending their territory from predators.  

There are reports of seeing more birds during the lockdown. Ornithologists say this is due to increased awareness of people’s surroundings while at home

Human activity influences bird behavior, even prompting them to communicate at less ‘busy’ times of day

The swift rise of human-made noise — also known as anthropogenic noise — over the past century has made this harder for birds. 

Just like humans who have to speak up in a loud setting, birds, too, have to sing louder to communicate properly in today’s noisy world, according to ornithologist Henrik Brumm, who heads the research group for the communication and social behavior of birds at the Max Planck Institute for Ornithology near Munich.

“This happens really fast,” Brumm told DW. “We found out that it takes roughly 300 milliseconds, so less than 1 second, for birds to readjust when the level of noise rises. So, when their surroundings become louder, they sing louder, too.”

Are birds getting quieter? Maybe.

Birds are already known to sing more quietly in the early morning hours of the weekends, says Brumm. The reason: there’s less traffic to compete with. 

With Europe on lockdown, Germany for its part, has seen passenger air travel slashed by over 90%. Moreover, car traffic has dropped by more than 50% and trains are running at less 25% their usual rates.

A recent study from the Max Planck Institute also suggests that chronic traffic noise can have a negative effect on embryo mortality and growth in zebra finches. This, in turn, could mean that the current lockdowns coinciding with mating season could lead to not only more, but also healthier hatchlings. That is, as long as their parents choose a spot that’s still safe from humans after the lockdown ends.

Though it’s difficult to speculate without real-time data, Brumm says, it stands to reason that the current period of quiet could mean birds might be singing more softly than usual, which would already be a huge benefit.

At land or sea, noise is bad news for animals

Birds aren’t the only animals that stand to benefit from less noise. According to a recent study published in the journal Biology Letters, noise pollution affects any number of creatures ranging from frogs, to shrimp, to fish, mammals, mussels and snakes.

In fact, another habitat garnering more and more attention for noise pollution is the ocean. As bioacoustics expert Christopher Clark described it in with Yale’s environmental magazine, the din from oil and gas activity, for example, is filling entire ocean basins with “one big storm of noise.”

While research on noise pollution and marine life, just like with ornithology, is in its early stages, a landmark study conducted in the days after 9/11 found that less shipping traffic seemed to make whales calmer.

Examining the feces of right whales — a species of baleen whale that can reach 15 meters in length and weigh up to 70 tons — researchers found that fewer ships in the waters along the US-Canadian coast correlated with lower stress hormones.

The noise levels from shipping traffic, whose 20–200 Hz hum disturbs sea life despite being a low frequency, decreased by 6 decibels, with a significant reduction below 150Hz .

An unprecedented time for researchers

Just like ornithologists, marine life researchers have also found correlations between noise and interruptions in behaviors like foraging and mating. Whales, like birds, also “mask.” That is to say, they sing louder to be heard over noise disturbances, be they high or low frequency sounds.

“It’s really a huge footprint that these activities have in the ocean,” according to Nathan Merchant, an expert on noise and bioacoustics at the UK’s Centre for Environment, Fisheries and Aquaculture Science (CEFAS).

Source: https://www.dw.com/

And the sources of noise pollution — ranging from shipping, to wind farms, to the sequence of powerful blasts from seismic air gun tests used to locate oil and gas deposits in the ocean deep — are even harder to escape in the ocean than on land.

“It has a lot to do with how sound travels under water. Sound can travel much further and much faster than in air,” Merchant told DW.

Instruments off the coast of North America, for example, can detect seismic air gun testing as far away as the Brazilian coast.

With many cruises suspended, oil freighter traffic impacted by an oil price crash and rig activity being run by skeleton crews to curb the spread of COVID-19, marine biologists could potentially find a treasure trove of data once they’re allowed to go back into the field. 

“We have underwater noise recorders at sea as we speak, but they aren’t cabled to land. So, we’ll find out when get out on a ship in several months’ time and get the data back,” Merchant said. 

The more interesting question by that point might be how marine life responds to a sudden reintroduction of the human cacophony after an unexpected period of rest.

Categories
Asia Noise News Building Accoustics

Railway Noise

Rail transport or train transport is one of the main transportation modes these days, both for transferring passengers and goods. Every day people commute to work and back home using trains in a form of subway systems, light rail transits and other types of rail transport. These types of system can create noise both to the passengers inside of the train as well as to the environment. In this article, we will discuss about noise source components that we hear daily both inside and outside of the train.

If we pay attention to the noise when we are on board of a train, there are more than one noise source that we can hear. The main sources for interior noise in a train are turbulent boundary layer, air conditioning noise, engine/auxiliary equipment, rolling noise and aerodynamic noise from bogie, as illustrated in the following figure.

By the way, we wrote and recorded the sound of Jakarta MRT. You can see the link below to help you imagine the train situation better.

Exploring Jakartan Public Transportation Through The Sound

Rolling noise is caused by wheel and rail vibrations induced at the wheel/rain contact and is one of the most important components in railway noise. This type of noise depends on both wheel and rail’s roughness. The rougher the surface of both components will create higher noise level both inside and outside of the train. To be able to estimate the airborne component from the rolling noise, we must consider wheel and track characteristics and roughness.

Another noise component that contributes a lot to railway noise is aerodynamic noise which can be caused by more than one sources. These types of sources may contribute differently to internal noise and external noise. For example, aerodynamic noise contributes quite significantly at lower speeds to internal noise while for external noise, it doesn’t contribute as much if the train speed is relatively low. For example, on the report written by Federal Railroad Administration (US Department of Transportation), it is stated that aerodynamic sources start to generate significant noise at speeds of approximately 180 mph (around 290 km/h). Below that speed, only rolling noise and propulsion/machinery noise is taken into consideration for external noise calculation. In addition to external noise, machinery noise also contributes to the interior noise levels. This category includes engines, electric motors, air-conditioning equipment, and so on. 

To perform the measurements of railway noise, there are several procedures that are commonly followed. For measurement of train pass-by noise, ISO 3095 Acoustics – Railway applications – measurement of noise emitted by rail bound vehicles, is commonly used. This standard has 3 editions with the first published in 1975, and then modified and approved in 2005 and again in 2013. The commonly used measures for train pass-by are Maximum Level (LAmax), Sound Exposure Level (SEL) and Transit Exposure Level (TEL).

For interior noise, the commonly used test procedure is specified in ISO 3381 Railway applications – Acoustics – Measurement of noise inside rail bound vehicles. This procedure specifies measurements in few different conditions such as measurement on trains with constant speed, accelerating trains from standstill, decelerating vehicles, and stationary vehicles. 

Written by:

Hizkia Natanael

Acoustical Design Engineer

Geonoise Indonesia

hizkia@geonoise.asia

Reference:

D. J. Thompson. Railway noise and vibration: mechanisms, modelling and means of control. Elsevier, Amsterdam, 2008

Federal Railroad Administration – U.S. Department of Transportation, High-Speed Ground Transportation Noise and Vibration Impact Assessment. DOT/FRA/ORD-12/15. 2012

Categories
Asia Noise News Building Accoustics

Noise and Vibration Monitoring for Construction Sites

In a densely populated city like Bangkok, most of the construction projects are surrounded by condominiums, offices or residential areas. The construction sites must control the noise and vibration that may affect the surroundings. Construction sites need to control the noise and vibration levels that they produce following the EIA standard.

To manage this, noise and vibration instruments are installed which automatically will send alarms to the construction company if the thresholds are exceeded.

Noise Monitoring Station

Sound level meter class 2 according to IEC61672-1 standard which can collect the data of SPL, LEQ and LMAX. These instruments are calibrated before they are installed at a construction site. The system has a LED display and warning light when noise levels in the site are over a trigger level, which is referred to in the standards for maximum sound levels around construction sites.

According to the announcement of National Environment Board no.15 BE.2540 (1997) in the topic of “Standard loudness”, the average sound 24 hour must not exceed 70 dBA and the maximum peak level must not exceed 115 dBA.

Sound level meter are designed to be used outdoors and an additional LED display was added by Geonoise which is a professional sound and vibration company. Sound level meter with LED display also can analyse the loudness in percentile (Statistical,Ln) or analyse the frequencies in 1/1 and 1/3 octave bands. In addition to storing vibration data, you can also create level notifications in Alarm Alert format before vibration levels exceed the standard value for monitoring the activities being performed.

Vibration Monitoring

In the construction industry, transportation Industry and most large industries vibrations will occur.
High vibration levels will cause structural damage to buildings, bridges, structures as well as nuisance or health risks to occupants in exposed (residential) buildings.

Therefore, it is necessary to comply with the standard of vibration in a building according to the Announcement of the National Environment Board Announcement No. 37, BE 2553 (2010) Re: Determination of Standard Vibration to Prevent Impact on Buildings and the measuring instruments need to comply with DIN45699-1.

At construction projects in Bangkok, most cause a lot of unwanted noise and vibrations. Vibration caused by construction projects are caused by piling work as well as the increased traffic of large trucks that enter and exit the construction site. To prevent that vibration levels will be exceeded, a vibration monitoring system will have to be installed.

The Announcement of the National Environment Board No. 37, BE 2553 Vibration standards to prevent impacts on buildings is the main regulation to comply with for construction sites in Thailand. The vibration standards are derived from DIN 4150-3 whereas buildings are classified into 3 types.

Building types according to DIN 4150-3:

  • Type 1 buildings such as commercial buildings, public buildings, large buildings, etc.
  • Type 2 buildings such as residential buildings, dormitories, hospitals, educational institutions, etc.
  • Type 3 buildings, such as archaeological sites or buildings that cultural values but not strong, etc.

In addition to storing vibration data, you can also create level notifications in Alarm Alert format before vibration level exceed the standard value for monitoring the activities being performed.

Categories
Asia Noise News Building Accoustics

Exploring Jakartan Public Transportation Through The Sound

Jakarta, the capital city of Indonesia, is home to 10 millions of Indonesia population. Recently the Indonesian government is being sued by a group of activists and environmentalists due to the unhealthy air quality in Jakarta. The plaintiff hopes that through the lawsuit, the Indonesian government can improve existing policies to address the air pollution issues.

On 18 Jul, according to the Switzerland-based pollution mapping service AirVisual, the Air Quality Index (AQI) of Jakarta is 153, categorized as unhealthy and may cause increased aggravation of the heart and lungs. The recommendation upon this condition is to wear a pollution mask and use air purifiers inside the room. The AQI Measures five criteria air pollutants (particulate matter, sulphur, dioxide, carbon monoxide, nitrogen dioxide, and ozone), and converts the measured pollutant concentration in a community’s air to a number on a scale of 0 to 500.

Air Quality Index – AirVisual

Jakarta is one of the largest urban agglomerations in the world. The uncontrolled increase in urban population is proportional to the number of the vehicle in Jakarta. According to Badan Pusat Statistik (Statistics Indonesia), the growth of motorized vehicle in Jakarta is 5,35% every year, on the other hand, this growth will increase the number of pollution in Jakarta. This statement is supported by the acting head of Jakarta Environment Agency, Andono Warih, the fuel residue of motorized vehicles was the main contributor to severe air pollution as 80 per cent of vehicles powered by diesel fuel operated from Jakarta Greater Area (Jabodetabek) to the capital.

Jakartan can contribute directly to overcome air pollution issues. Public transportation is an environmentally friendly mode of getting around. Because public transportation carries many passengers on a single-vehicle, thus it can reduce the number of vehicles as well as reducing the number of emissions from transportation in a dense urban area. Further, public transportation can help Jakarta to reduce the smog, to meet air quality standards and to decrease the health risk of unhealthy air quality. 

The urban transportation system in Indonesia consists of buses, trams, light rail, metro, rapid transit and ferries. Particularly in Jakarta, urban rail-based transportation, such as Commuter Line Train, Light Rail Transit (LRT) and Mass Rapid Transit (MRT), provides mobility and access to the urban area.

MRT Jakarta Phase 1 – MRT Jakarta

The first phase of MRT Jakarta (MRT-J) has been operating since March 2019. In daily operation, the train runs from Lebak Bulus Grab Station to the Bundaran HI Station. There are 13 stations along the railway; the underground stations are Bundaran HI, Dukuh Atas BNI, Setiabudi Astra, Bendungan Hilir, Istora Mandiri, and Senayan Station. Meanwhile, the overground stations are ASEAN, Blok M, Blok A, Haji Nawi, Cipete Raya, Fatmawati, and Lebak Bulus Grab Station. The MRT-J only needs 30 minutes to travel along the 16 kilometres railway, starting from Lebak Bulus Grab Station in South Jakarta to the Bundaran HI Station in Central Jakarta.

There are 16 train lines available to take the passengers getting around. Based on the MRT-J website, In weekdays operation, the trains operate at 05.00 WIB to 24.00 WIB with a total of 285 trips. Meanwhile, in weekend operation, the trains run at the same hour with a total of 219 trips.

During the promo operation (1 April – 12 May), the average number of daily passengers reached 82,643, whereas after the full tariff was applied, the average per day was 81,459.

The following pictures will show you the scenes of MRT Jakarta.

So what do you think? Have you tried getting around using MRT Jakarta? If you have never, try immediately and feel the different sensation of Public Transportation in Indonesia.

Further, through this article, I would like to invite you, explore the MRT Jakarta through a different perspective, that may be for a group of people this method is still rarely used, a sound.

Do you realize that sound can tell us about character, place, and time? Sometimes, it informs us in ways visuals can’t, and that is the idea of what we are going to do right now. Later you will hear, a file of recorded sound of MRT-J in its daily operation.

The sound was recorded by the soundwalk method, any excursion whose primary purpose is listening to the environment. It is exposing our ears to every sound around us no matter where we are. We may be at home, walking across a downtown street, or even at the office. Meanwhile, in this case, our environment is inside the line of MRT Jakarta. The goal is to capture any sound sources that exist during the operation of MRT-J, including the activity of the passengers.

The sound was recorded by using a mounted microphone on the iPhone X at a level of 1.2 m above the ground. The following sound is a recorded environment while the MRT-J was travelling from Bundaran HI Station to Setiabudi Astra Station, the duration of recording sound is 4 minutes and 40 seconds. Please use an earphone or any similar devices to listen to the audio for a better experience.

Caution: please set the volume around 50 – 70 % of the maximum volume.

After listening to the sound, can you identify what sound sources are presented in the recording? Here are the sound sources that I have identified:

  1. Engine sound increases speed
  2. Public Address system
  3. Engine sound
  4. Rail friction
  5. Passengers’ activities (cough, sneeze, conversation, footsteps, etc.)
  6. The sound of the door opening
  7. Brake squeak

Now we have identified the sound sources that are presented in the recording. But, do you know how many decibels that I have to endure while travelling using the MRT-J? In this article, manual measurements of noise levels were performed with a sound level meter in the MRT Jakarta with passengers on its usual route. A-weighted sound level measurements were recorded directly from one station to the next during the time between 08:00 and 09:00, using a calibrated microphone on a stand at a level of 1.2 m above the ground. The results of equivalent continuous A-weighted noise levels Leq (LAEq) in the MRT-J with passengers on its usual route from one station to the next is shown in Chart 1. 

Leq is the A-weighted energy means of the noise level averaged over the measurement period. The results from the measurements show that the A-weighted noise level is varied between 77 dB to 82 dB. Further, if we look closely into the Chart, the noise level is fluctuating. It can be caused by a lot of factors, such as: 

  1. The position of MRTJ (When MRT-J inside the tunnel, the noise can be levelled up due to the reflection phenomenon).
  2. Speed (The machine indicates producing a higher noise when in the maximum speed).
  3. Path Crossing.
  4. The Public Address System Volume.

Moreover, the level of continuous noise in Chart 1 represents a quite noisy environment. According to The National Institute on Deafness and Other Communication Disorders, states that Long or repeated exposure to sound at or above 85 dB can cause hearing loss. Thus, according to the measurement results, I suggested you wear ear protection during commuting by MRT-J. The earplug is one of the equipment that we can use to protect our hearing; you only need to spend a few thousand rupiahs for this. Wearing earplugs can help you to reduce the noise by 18 – 34 dB, it depends on the models/brand. For more accurate results, we need to do a complex measurement, such as:

  1. Add measurement point (In this article, the measurement was done only in a measurement point, at the second car of the line).
  2. Add a velocity as a measured parameter.
  3. Add the measurement time; the measurement can be done during the operation hour, non-stop. (05:00 – 24:00 WIB).

Nonetheless, the idea of showing the measurement results is spreading noise awareness. Noise sticks with you around, even common sounds you hear at work or home can contribute to long term hearing loss and other health risks, they are everywhere, but only a few people are aware of it. Noise pollution is a health threat nobody is talking about. Here are some parameters to help you determine acceptable — and dangerous — noise levels:

  • 45 dB: nightly noise ordinance threshold set by many municipalities concerned with industrial noise exposure for residents
  • 65 db+: exposure for prolonged periods can cause physical and mental fatigue
  • 85 dB+: can cause permanent hearing loss if exposed for extended periods
  • 85-120 dB: dangerous over 30 minutes of exposure
  • 120-130 dB: can cause permanent hearing loss for exposure over 30 seconds
  • 130 dB+: not only are these noises painful, but hearing protection should always be used if avoidance is not possible.

Everyone needs to take care of their ears and hearing, as damage to the auditory system could be irreparable. The loss because of the noise exposure is gradual; you might not notice the signs, or you ignore them until they become more apparent. Please do protect your ears. 

Reference:

https://www.theguardian.com/world/2019/jul/02/jakarta-residents-to-sue-government-over-severe-air-pollution

http://support.airvisual.com/knowledgebase/articles/1185775-what-is-aqi

https://doi.org/10.1016/j.ecss.2018.10.017

https://jakarta.bps.go.id/publication/2018/10/03/cb1285d8dbe8be8754a5830d/statistik-transportasi-dki-jakarta-2018.html

https://en.tempo.co/read/1214627/jakarta-air-pollution-mostly-caused-by-motorized-vehicles-agency

https://nowjakarta.co.id/city-guide/explore-jakarta/city-guide-by-now-jakarta-s-transportation-guide

https://www.businesstimes.com.sg/asean-business/indonesia-accelerating-urban-transportation-development-with-public-private

Westerkamp, Hildegard (1974). “Soundwalking”. Sound Heritage

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5308171/

Categories
Asia Noise News Building Accoustics

Feeling Unproductive? You Might be Overlooking This Productivity Killer

Feeling Unproductive in Office – Geonoise Instruments

We believe that the best way to be highly productive is to be able to get into our monoideal state. Josh Kaufman says in his book “The Personal MBA”:

Monoidealism is the state of focusing your energy and attention only on one thing. It’s often called a “flow” state: clear, focused attention on one subject for a long period of time.”

For this to happen, potential distractions and interruptions need to be eliminated. This is the reason for some people, working early in the morning or late at night can feel very productive – because on a normal day, no one is going to call you at 4 in the morning.

However, most of us do our work in an office which does not operate at those silent, undistracted hours. The good news is, we still can manage our potential distractions by knowing what distracts us the most. This can be done by allocating a time when you want to be in your monoideal state and free yourself from distractions during that time. For example, you can put your phone into flight mode and turning off email notifications from 8 to 11 and start to check emails and communicating with the outside world from 11 until lunch. The timing will depend a lot on the type of work you are doing and how much time will you need to be in monoideal state.

Unfortunately, there are things that is out of your locus of control – there is a retrofitting job upstairs, your co-worker decided to sing along to the song he is listening to, people in the other room are laughing loudly (are they talking about their boss?) and so on. If it’s not in front of your eyes, for example pop-up notifications on your screen, most of the distractions come to you in a form of sound, or I think it’s better to call it “noise”.

Noise is a productivity killer that you might be overlooking, especially if you have passed the stage of being distracted by your phone, browsing Facebook on your computer and looking at cat videos on Youtube. Fortunately, noise is manageable in a few different ways. The most viable option for an existing office is to make noise-related rules and to make everybody aware that noise can reduce their productivity. For example, companies can make rules that retrofitting job, singing and gossiping must be done outside of office hour. Another way to fix this is to separate areas for people who want to be focused and areas where people can socialize and discuss with their co-workers.

The best way to manage noise? Is to take noise into consideration from the beginning of the design process of the working space. This can be a long and complex process where there are a lot of aspects to be considered in designing an ideal office. It needs a balance between visual pleasure, company’s philosophy, functionality, health, safety and all other aspects that we want to take into account. A lot of times, all those aspects will relate to noise or acoustics in some ways, depending on each unique case.

For us acousticians, these are the things that we typically think about when helping others to design their working space (and actually any other built environment):

  • Ambient noise: We want the noise level inside of the working space to be reasonably low, whether it is intrusion from outside such as traffic, railway, aircraft and neighbouring building (neighbour’s mechanical system can be quite noisy), or the noise from inside the building such as HVAC system and lifts.
  • Sound insulation: We don’t want to hear sound that we don’t want to hear from the next room, upstairs or downstairs. By designing a suitable ceiling, flooring and wall systems, a sufficient sound insulation can be achieved.
  • Room acoustics: We want to be able to listen comfortably and understand verbal information that we want to. This is critical especially in meeting rooms and event space.
  • Sound reinforcement and public address system: We want the sound reinforcement and public address system to be heard clearly while not disturbing others who don’t want to hear it.

All the above can also be done after the building and the working space is built. But if it’s done before it’s built, you will have a lot more options and be more cost efficient rather than changing what is already been built.

So, if you are a highly productive person, or if you want to become one, we would suggest you to consider noise in choosing the space you are working in.