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Hotel Room Acoustics – how noise affects a person’s stay in the hotel

Hotel Room Acoustics – how noise affects a person’s stay in the hotel

Hotels have been playing an important role during the current pandemic. In certain countries, the local governments have announced that it is compulsory for those entering the country from overseas to carry out hotel quarantine. Taking Malaysia as an example, travellers entering the country regardless from any country are required to undergo hotel quarantine for up to 10 days (as of January 2021), in which the local authorities will arrange the rooms for them unless the travellers opted for Premium Package which of course, costs higher than the standard ones. Travellers will have to take COVID tests in between to ensure that they are COVID-negative and isolating them in the hotels will make sure that there will not be the possibility of spreading the virus to the public since all travellers should be taken as potential risk carrier.

Hotel room comfort

Many may be wondering: How is the cleanliness of the room? Are the meals provided good? What about the Wi-Fi strength there?

But there is one thing that people sometimes forget about: Noise. From the study done by the J.D. Power North American Hotel Guest Satisfaction Survey, it has been consistently shown that complaints on noise issues are significantly under-reported, and hardly being resolved in the end (Simonsen, 2019). Imagine living in a confined space for more than 10 days, where you need to experience constant noise coming from your neighbours, or from outside the room like traffic or construction noise, how will you feel? Looking at some hotel review posts in the Malaysia Quarantine Support Group (MQSG) created to aid travellers coming into Malaysia, there seem to be numerous posts complaining about noise nuisance during their quarantine period. The typical problems faced by members include:

  1. Traffic noise – hotel is located next to busy road
  2. Construction noise in the day from nearby sites
  3. Loud neighbours – speaking loudly especially at sleeping hours

To be exact, these are the similar nuisance one would experience in residential houses.

For short term stays, these may not be the main concern, but it is a totally different case for a quarantine. Unreasonable amount of noise daily for long term, especially after a tired flight and transition at the airport, will lead to unwanted circumstances on a person’s health (physically and mentally).

Noise and Sleep Disturbance

For people who are extremely sensitive to noise, the first thing that can be observed will be that they cannot sleep or even rest well. This will result in sleep deficiency, which slowly drains off the energy to carry out daily tasks. According to Hume, many from the research field claimed that sleep disturbance caused by environmental noise has the most detrimental effect to health. Having an undisturbed night of sleep is even taken to be a fundamental rights and prerequisite to ensure continued health and well-being (Hume, 2010). Hume mentioned that noise pollution can be described as the “modern unseen plague” which may interfere with cognitive processes hence disturbing sleep quality.

To overcome the problem of noise affecting sleep quality, the World Health Organization (WHO – European Office) has brought in experts with relevant documents in recent years to establish the Night Noise Guidelines for Europe. The guidelines contain the latest reviews of noise disturbance and the potential risk to human health. Below are the four ranges of continuous external sound level at night, relating night noise and the populations’ health effects:

<30 dB – no substantial biological effects could normally be expected

30-40 dB – primary effects on sleep start to emerge and adverse effects in vulnerable groups

40-55 dB – sharp increase in adverse health effects while vulnerable groups become severely affected

>55dB – adverse health effects occur frequently with high percentage of the population highly annoyed

These guidelines help to understand the effect of noise on sleep, although a large extent of this topic still relies on fully understanding the fundamentals of the nature of sleep.

Acoustics Solutions for Hotels

As mentioned in the previous sections, the noise complaints for hotel rooms mainly cover traffic noise, noise from neighbours and construction noise. Since sound travels in wave forms, soundproofing will be one of the best concepts to act as a barrier that can effectively stop the sound waves from entering a room from outside.

Typically, there are four methods to achieve the soundproofing effect for hotel rooms (SoundGuard, 2019):

  • Absorption – adding sound insulating materials such as mineral wool or fiberglass for sound absorption, thus preventing sound from passing through
  • Damping – soundwaves often cause vibrations between air particles. Damping helps in reducing or eliminating the vibrational effects by acting as a barrier that does not vibrate
  • Decoupling – In layman terms, this also means separating the walls by adding an insulation layer between the two layers of drywall.
  • Mass – Utilizing thicker, heavier, or denser materials to block sound

While choosing the right material for insulation, it is important to take note on the Sound Transmission Class (STC) rating. The STC rating defines the effectiveness of materials in attenuating airborne sound. The lower the STC rating, the less sound that can be effectively blocked. Therefore, to achieve good insulation results, it is better to use a material with higher STC value.

When should you implement acoustical solutions?

Ideally, it is best to start from the very beginning, which is during the project planning stage (yes, before you even start building it!). Quoting a line said by Scott Rosenberg, the president of Jonathan Nehmer + Associates, and the principal with HVS Design, “You have to think about the inside walls like they’re on the outside” (Fox, 2018). This was said for atrium style hotels which are normally structured like giant echo chambers, where noise from the lobby may travel up to the penthouse suite due to the structure. In the planning stage, allocating which part of the hotel goes where is also crucial to make sure you keep sounds in the right places, and nowhere else. For example, it is important to locate the facilities like gyms, pub, or even spa strategically so that the noise from these places will not affect the guests staying in the hotel rooms. If you really must put them above/below rooms, make sure to use walls or ceilings that are properly insulated.
For existing hotels, another good time to improve the acoustics of the hotel will be during renovation periods. Since you took the step to upgrade your hotel looks and structure, why not consider soundproofing as well? It will definitely help to raise the customers’ satisfaction during their stay.
The areas that can be considered for hotel soundproofing during renovation include:
• Floors – adding soundproofing underlay
• Ceilings – using decoupling methods (dual-layered drywall)
• Doors – changing to solid-core heavy doors with seals
• Walls – adding insulation between walls / use soundproofing paint

 

How do you know if your hotel needs acoustical improvements?

Although some may only start treating the problem after getting significant complaints from customers, hotel owners should consider taking the initiative to find out the noise condition in the building. A good start will be to carry out noise measurement tests to monitor the condition in each room. Having noise data from the measurements will help you understand what the situation is, and how you should resolve them. This is where an acoustics consultant should step in.
It is suggested to consult the acoustics specialists to get the most suitable solution for your case, because not all solutions can be applicable for all conditions. Acoustics consultants can help you to analyse the condition by using methods like indoor noise mapping, material insulation calculations and even tiny suggestions like adding certain types of furniture to aid sound absorption in the room itself.


Effects of Acoustics Improvement to the Hotel

It is proven that by enhancing the acoustics of hotels, business can be improved too. For example, Premier Inn in the UK has pioneered the new design of “floating bedroom” in 2011 at its hotel in Leicester Square. This new design allowed the hotel to resolve the environmental noise and the noise coming up from the nightclub on the ground floor. Premier Inn had also changed their focus from cost to customers’ sleep quality, which enabled them to become one of the best-rated hotels in London (Simonsen, 2019). Thus, the hotels’ business and reputation will strongly improve by taking care of the noise aspects.
Now, back to the starting topic of this article. Hotels are no longer only used as the accommodations for vacations or business trips. Hotels play an important part during this pandemic, being the quarantine centres in many countries. Therefore, it is important to ensure the customers’ (or those under quarantine) comfort during their stay, voluntarily or not. Their reviews make a lot of difference, which will highly impact a hotel’s image to the public. Most importantly, good, soundproofed room means less noise, resulting in better living and sleep quality. Hence, hotel owners are urged to investigate the acoustics aspects of their property, for themselves, and for the customers.


References

Fox, J. T. (2018, July 17). Careful hotel design keeps noise in check. Retrieved February 4, 2021, from Hotel Management: https://www.hotelmanagement.net/design/careful-hotel-design-keeps-noise-check


Hume, K. (2010). Sleep disturbance due to noise: Current issues and future research. Noise Health, 12(47), 70-76. Retrieved February 2, 2021, from https://www.noiseandhealth.org/article.asp?issn=1463-1741;year=2010;volume=12;issue=47;spage=70;epage=76;aulast=Hume


Simonsen, J. (2019, June 20). Why and how to reduce noise in hotel rooms. Retrieved February 3, 2021, from Rockwool: https://www.rockwool.com/group/advice-and-inspiration/blog/why-and-how-to-reduce-noise-in-hotel-rooms/


SoundGuard. (2019). Hotel Sound Reduction – How to Soundproof a Hotel Room. Retrieved February 3, 2021, from SoundGuard: https://soundguard.io/hotel-sound-reduction-soundproof-hotel-room/

Categories
Asia Noise News Environment

Noise in Malaysia

What Covid-19 did to Malaysia

2020 has been a year full of ups and downs. One big thing that affected, in fact, is still affecting the whole world is undeniably the Covid-19 pandemic. No doubt that the pandemic has caused a lot of downhills in the development of many aspects, like economy and social, but there is one thing that have shown obvious positive sign during this situation: the environmental change.

Figure 1 A picture showing the clearer skies in Kuala Lumpur, the capital of Malaysia (Photos: Filepic).

According to a Malaysian news report by Ming Teoh from The Star, the movement control order (MCO) that was carried out to tackle the Covid-19 spread in Malaysia has brought positive environmental impacts to the country (Teoh, 2020). People were amazed by the clean rivers, clear blue skies and the recovery of nature and wildlife. Of course, due to the MCO where a lot of human activities were restricted, the streets and urban roads have been very quiet as compared to the usual noise level. The improved noise quality resulted in lower noise pollution, which made the sounds of the fauna more apparent. But once everyone gets back to normal life when the MCO is lifted, how long can this positive environmental situation last? Will there be enough time for the environment to heal properly?

The Department of Environment (DOE), Ministry of Energy, Science, Technology, Environment and Climate Change (MESTECC), Malaysia

The Department of Environment (DOE) from the Ministry of Energy, Science, Technology, Environment and Climate Change (MESTECC) of Malaysia have been very concerned about this issue all the while, specifically on the noise quality of the country. They have constantly been updating the guidelines to handle noise or vibration for various applications, for example vehicle-noise, ambient noise, or outdoor noise sources in the environment. In one of the published guidelines for environmental noise limits and control (2009), the DOE have specified a table showing the permissible sound levels for different applications, shown in Table 1 as one of the examples from the guidelines (Air & Noise, 2019). 

Table 1 An example of the permissible sound levels listed in the guidelines published by the DOE.

The permissible sound levels differ by the applications (i.e. use of land, human density) and the different times of the day, to ensure that the circumstances of various conditions are taken into account during the sound level measurements. For instance, the ambient noise limits are set such that it is an absolute limit based on the average level of noise (which should not be exceeded in a specified period), or in accordance with a relative limit based on the permitted increase in noise level with respect to the background level. It is mentioned that the limits should always be consistent with the environmental noise climate of the location. The rest of the noise limit schedules listed in the guidelines include those for land use, road traffic, railway/transit trains, construction, and maintenance, which are the main sources of outdoor noise in the country. 

Besides that, the report also covers guidelines on planning process, noise impact assessments, quantifying of noise disturbance, and guidance in environmental noise mitigation through planning and control. These are ideally applied in new and existing projects planning, in which the projects can cover anything that involves noise, as a potential concern or needed to be measured and assessed. This is a very imperative measure from the DOE to enforce noise control in the country to work on controlling the noise impact of the relevant applications, thus overcoming the noise pollution in Malaysia. With these actions being taken and followed, the goal to maintaining a better noise quality in the country can be achieved in near future.

Written by:

Khei Yinn Seow

Mechanical Engineer

Geonoise Malaysia

khei@geonoise.asia 

References:

Air & Noise, P. S. C. S., 2019. Guidelines for Environmental Noise Limits and Control (Third Edition), Putrajaya: Department of Environment Malaysia.

Teoh, M., 2020. Blue skies, less waste: Covid-19 and the MCO’s effects on the environment., s.l.: The Star.

Categories
Asia Noise News

Soundscape Under Covid-19

Many around the world are experiencing life with very low noise levels due to restrictions as we are confined to our home and there is a decrease in the industrial, transportation and leisure activity. This provides a wonderful opportunity to quantify and record for the future the lower noise levels of our soundscapes. With the reduction in shipping there is also a change in the underwater soundscapes.

Nowadays there are a high number of noise monitoring systems (noise monitoring terminals, city wide systems, underwater systems etc.) installed all over the world which will capture this information for the future. However, there are many acousticians working from home with access to a sound level meter that can be used to capture the soundscape from their balcony or from their garden and compare the before and after the restrictions.

The IYS 2020 committee has provided a central contact between a number around the world who were thinking similarly that there would be some benefit in coordination and a little standardization in the capture of the data. Marçal Serra from CESVA has taken a lead to set up a LinkedIn group COVID-19 Noise Reduction (at www.linkedin.com/groups/13844820/) and with hashtag #COVID19NoiseReduction for any posts.

The following is a general structure for those who wish to participate and share their data in the future. But do not break your confinement to report this data!

  • Place: Country and city (e.g., Spain village near Barcelona)
  • Primary noise source: (e.g., Traffic noise: note number of lanes per direction or Social noise: note if café/bar/restaurant/sporting)
  • Noise measuring system: The noise measuring system used to measure LduringLbefore, and Lafter
  • Noise level during COVID-19 confinement: Lduring, expressed as a weighted overall level (preferably LAeq,1 hour), spectrum or psychoacoustic metrics as Loudness. It could also be reported as an image of the noise time history or a weekly color map and/or compiled into a report/article/conference paper with the measurement details and the comparison data
  • Noise level before & after COVID-19 confinement: Lbefore & Lafter, expressed in the same way as Lduring and over the same time period.
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.