Friday 30 November 2018

Critical Reflection 2: Showcase Presentation

During the showcase, team SFLR stood out significantly for their style of presentation. Although their ideas had a few flaws, the delivery was intriguing and full of life. Right from the beginning, the team was full confidence and they presented themselves very well. Confidence was a strong point in the presentation as they were not intimidated by the size of the audience or the presence of the judging panel. It made the audience take notice of them and in turn would pay more attention to the presentation. The confidence also helped to show their passion in their idea and it added to the overall delivery of the presentation. Without the use of a mic, they managed to project their voice to the audience clearly and enunciated each word clearly.

The slides which they used enhanced the understanding of the idea greatly by including pictures and videos of how their product would work. They had little to no words on each slide and were mostly made up of pictures. Most of the explanation was done verbally and this helps to capture the attention of the audience and enable them to listen to the presenter more attentively instead of reading information from the slides.

Body language was another critical factor in the near-perfect presentation. Although a few of them kept looking back at the slides occasionally, they maintained eye contact with the audience throughout the presentation and were very expressive with their hands and body without looking unnatural or forced. They were squared to the audience and did not have telltale signs of nervousness such as placing their hands in front or behind them.

Group SFLR showed the audience how to deliver a smooth and intriguing presentation by simply rehearsing well, being knowledgeable in their project and being confident in themselves to stand in front of an audience. They may not have had the most applicable idea but, they certainly had the best presentation.

Critical Reflection 1: Module and Project Learning

Looking back on this module, I realized how much weaker my command of English had become. I used to be confident with my speaking and writing skills, but after 2 years without studies, my command of English has dropped. Revisiting English as a communication module has certainly helped in improving on the skills that I had attained before as well as learning new English structures that I never knew about.

My goals for this course were to improve my workplace communication skills as well as my writing skills. My communication skills are improving but it is not at my level of expectation. There are still many areas which require improvement. I believe that my writing skills have not improved much over this course as I am still making simple grammar mistakes in my reports. However, the ability to write well improves over time and with experience. I am sure that my writing skills would improve with the help of the websites given to us and further applying them to my other reports in the future.


Throughout the project, there were many factors which affected the learning process. One area where we had many difficulties in is looking for credible websites to get our information from. Since our solution was a product that is available on the market, most of our sources came from brands’ websites that were selling the product. Therefore, we were not sure if they could be used as a credible source of information for the project. As we did research on our product and its capabilities, we overcame the problem by collating different brands’ products and compared them against each other to ensure its reliability. At the end of the day, I took away many things from this project work and one of those, where the importance of having reliable sources.

Thursday 1 November 2018

Technical Report Draft 2

Executive Summary
Report on the solution to having cleaner indoor air using electrostatic precipitators to filter out PM2.5 particles from circulation indoors.

Background
Despite being a clean and green country, the carbon emissions in Singapore is relatively high in proportion to its size. This proposal is a response to the poor air quality that we breathe in due to the high carbon emissions.

Singapore is one of the most well-established countries in the world. We have many vehicles roaming our streets along with industrial building constantly releasing harmful particles into the air daily. A research done by the National Climate Change Secretariat of Singapore (2018) stated that “Singapore contributes to 0.11% of the global emissions”. The percentage may seem small, but considering the size of our country, it is a rather large contribution. The article further shows that Singapore ranks 123rd place in terms of CO2 per dollar GDP, ahead of countries like the United Kingdom and France which are many times larger than our country. This shows that Singapore does have an issue with air pollution.

Air is essential to every human being, however, the air that we are breathing in could be affecting our health in the long run. Such harmful particles are known as ‘particulate matter 2.5’, PM2.5. It refers to tiny particles that are 2.5 micrometers (µm) or less in diameter, often called fine PM. PM2.5 causes by men are more severe than natural sources, the particles are directly emitted into the air from motor vehicles, forest burnings, and industrial gases. As they are so small and light, they stay longer in the air causing the air to be polluted and increases the chances of people inhaling it. Due to their tiny size, the particles can enter our lungs and circulatory system. This could cause health hazards both in the short and long run. An article published on the US National Library of Medicine National Institute of Health (NCBI, 2002) stated that “Long-term exposure to combustion-related fine particulate air pollution is an important environmental risk factor for cardiopulmonary and lung cancer mortality.” Based on a guideline by the World Health Organisation (WHO, 2018), the PM2.5 levels should be at 10µgc annual mean and 25µgc for 24 hours mean. According to the psi index by The National Environment Agency (2018), the psi levels in Singapore currently falls within the range of 50μg/m3 to 60μg/m3 daily, which are beyond the levels listed by WHO.

The factors which have contributed to PM 2.5 in Singapore are mainly from vehicles and industrial factories. These PM 2.5 can also be the product formed by chemical reactions in the atmosphere. An article by The Straits Times stated that “due to the concentration of particle vapour and local emissions - from cars and factories”. These small-sized particles are not entirely from the neighbouring country that carries out deforestation which in the later part of the article stated, “experts point to culprits closer to home: factories and cars”.  

During the haze period, one of the strategies that Singaporeans use to counter haze problem is to stay indoors and use air-conditioners, as is it advisable to limit outdoor activities when the PSI level is high. While all doors and windows are closed, it can limit the particles in the haze from entering the houses. However, conventional air-conditioners are unable to filter the tiny particles like PM2.5, so there are still chances of breathing them in.

When indoors, the air condition will always be on. A building grade air conditioning uses Heating, Ventilation and Air Conditioning system, known as HVAC. The main purpose of a HVAC system is to provide thermal comfort and acceptable indoor air quality. The most common HVAC system used in buildings are called packaged rooftop units. Unlike the split system which is used in residential air conditioning units, it has everything stored in one unit, therefore the name packaged. The packaged rooftop units include an evaporator coil, fan, compressor, condenser and are situated on the roof.

Problem Statement
An ideal innovative campus should adopt an advanced approach which can circulate clean indoor air and provide a conducive environment to study without being affected by the air quality. Due to the location of the SIT@Dover, the air quality is affected by the carbon emission of cars along the highway and the industrial buildings near the coast, resulting in a build-up of air pollution around the school which would be harmful to students. Inserting electrostatic precipitators to the air cons, it will filter out PM2.5 particles from the indoor air and circulate back clean air around the room.

Purpose Statement
The purpose of this report is to propose to the facility manager of SIT@Dover to install electrostatic precipitators into the current campus and, to emphasise to the facility manager that this advance approach can provide a clean and conducive learning space for the students and staff alike.

Proposed Solution
Our proposed solution to removing PM2.5 particles from circulation is to introduce electrostatic precipitators in our air conditioning filters. Electrostatic Precipitator is a highly effective device that removes suspended dust particles that are smaller than PM 10 by applying a high-voltage electrostatic charge and collecting the particles on charged plates. Clean air would then be distributed back out for circulation.

Benefits of Electrostatic Precipitator       
The are many benefits that Electrostatic Precipitator provides which are: able to remove tiny dust particles which are as small as PM 0.01 and ease of operation. This shows that this precipitator is definitely a great investment which SIT@Dover can consider as the location of the school is situated beside the expressway. Thus, it is beneficial for the students as the students are able to study comfortably without any difficulties in concentrating due to the dust.                                                                                                                                          
Clean air
The electrostatic precipitator would be able to circulate clean air around the room by removing small dust particles from the air. It would improve the respiratory health of students and staff.
Low operating costs
With the installation of electrostatic precipitators, it has a long service life and requires little maintenance as well as low operating costs unless used at high efficiencies. This would prove to be a good investment in the long run with its low operating costs.


Evaluation
Electrostatic Precipitators have a high capital cost which is a big factor to consider before installing it on the campus. This will most likely be the biggest factor as campuses are funded by the government and may not have the budget to install these filters on a large scale. On top of that, the electrostatic precipitators are not flexible. Once installed, it is hard to move it.

However, with all this limitation in place, the advantages outweigh them all. As most HVAC systems are located on the roof, the space that an electrostatic precipitator needs is not a big issue. The installation of these precipitators will most likely be permanent which means that flexibility will not be an issue either.

Limitations of Electrostatic Precipitator
However, nothing is perfect. There are also some disadvantages of Electrostatic Precipitators, for example, the system is difficult to change working conditions once it is installed for the air-conditioner and it is bulky.
The electrostatic precipitator can only be used to collect dry and wet pollutants. It cannot collect gaseous pollutants.
In addition, it requires a high initial cost to install, not practical for small industry or household use.
Moreover, the equipment itself is quite expensive and periodically maintenance cost is high and taking extra space.
References
Ambient (Outdoor) Air Quality and Health. (2018). Retrieved October 31, 2018, http://www.who.int/news-room/fact-sheets/detail/ambient-(outdoor)-air-quality-and-health

Pope CA 3rd, Burnett RT, Thun MJ, Calle EE, Krewski D, Ito K, Thurston GD. (2002). Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/11879110


PowerClean™ Electrostatic Precipitator with Automatic Cleaning [Image]. Retrieved from http://www.airscrubbersinc.com/products/kitchen-exhaust-electrostatic-powerclean.htm



Tuesday 30 October 2018

Technical report draft 1

Despite being a clean and green country, the carbon emissions in Singapore is relatively high in proportion to its size. This proposal is a response to the poor air quality that we breathe in due to the high carbon emissions.

Singapore is one of the most well-established countries in the world. We have many vehicles roaming our streets along with industrial building constantly releasing harmful particles into the air on a daily basis. In fact, a research by the National Climate Change Secretariat of Singapore stated that “Singapore contributes to 0.11% of the global emissions”. The percentage may seem small, but considering the size of our country, it is a rather large contribution. The article further shows that Singapore ranks 123rd place in terms of CO2 per dollar GDP, ahead of countries like the United Kingdom and France which are many times larger than our country. This shows that Singapore does have an issue with air pollution.

Air is essential to every human being, however, the air that we are breathing in could be affecting our health in the long run. Such harmful particles are known as ‘particulate matter 2.5’, PM2.5. It refers to tiny particles that are 2.5 micrometers (µm) or less in diameter, often called fine PM. PM2.5 causes by men are more severe than natural sources, the particles are directly emitted into the air from motor vehicles, forest burnings, and industrial gases. As they are so small and light, they stay longer in the air causing the air to be polluted and increases the chances of people inhaling it. Due to their tiny size, the particles are able to enter our lungs and circulatory system. This could cause health hazards both in the short and long run. An article published on the US National Library of Medicine National Institute of Health (NCBI, 2002) stated that “Long-term exposure to combustion-related fine particulate air pollution is an important environmental risk factor for cardiopulmonary and lung cancer mortality.”Based on a guideline by WHO, the PM2.5 levels should be at 10µgc annual mean and 25µgc for 24 hours mean. According to the psi index by NEA, the psi levels in Singapore currently falls within the range of 50 to 60µgc which are beyond the the levels listed in the WHO guidelines

The factors which have contributed to PM 2.5 in Singapore are mainly from vehicles and industrial factories. These PM 2.5 can also be the product formed by chemical reactions in the atmosphere. An article by The Straits Times stated that “due to the concentration of particle vapour and local emissions - from cars and factories”. These small-sized particles are not entirely from the neighbouring country that carries out deforestation which in the later part of the article stated “experts point to culprits closer to home: factories and cars”.  

During the haze period, one of the strategies that Singaporean use to counter haze problem is to stay indoors and use air-conditioners, as is it advisable to limit outdoor activities when the PSI level is high. While all doors and windows are closed, it can limit the particles in the haze from entering the houses. However, conventional air-conditioners are unable to filter the tiny particles like PM2.5, so there are still chances of breathing them in.

When indoors, the air conditional will always be on. A building grade air conditioning uses Heating, Ventilation and Air Conditioning system, known as HVAC. The main purpose of a HVAC system is to provide thermal comfort and acceptable indoor air quality. The most common HVAC system used in buildings are called packaged rooftop units. As the name goes, it is located on the rooftops.

An ideal innovative campus should adopt an advanced approach which can circulate clean indoor air and provide a conducive environment to study without being affected by the air quality. Due to the location of the SIT@Dover, the air quality is affected by the carbon emission of cars along the highway and the industrial buildings near the coast. This results in a build-up of air pollution around the school which would be harmful to students. Inserting electrostatic precipitators to the air cons, it will filter out PM2.5 particles from the indoor air and circulate back clean air around the room. The purpose of this report is to propose to the facility manager of SIT@Dover to install electrostatic precipitators into the current campus and, to emphasise to the facility manager that this advance approach can provide a conducive learning space for the students.


Thursday 11 October 2018

Readers Response Draft 3

In the excerpt Guidelines for Good Indoor Air Quality in Office Premises, (Ministry of the Environment [MNV], 1996) stated that buildings should be designed and constructed regarding the pollution which may occur within the building. The Air Conditioning and Mechanical System (ACMV) should be constructed in a manner that reduces the spread of contaminants. (MNV, 1996) also mentioned that the materials and surfaces of the building should not emit any harmful chemicals, while the placement of outdoor air intakes should not be situated near sources of pollution. Buildings should be constructed in ways that prevent contaminants from entering. To ensure contaminants do not enter, the air ducts should be fitted for easy maintenance and inspections as well as being built with materials that produce less friction. Although the excerpt mentioned that materials and surfaces can add to the poor indoor air quality, it fails to mention how dangerous the emitted chemicals are and why having good indoor air quality is essential to our health.


Firstly, the excerpt states that the materials and surfaces should not emit harmful chemicals. The harmful materials are not made known to us or in what ways are they a risk to our health. One common material used in construction is asbestos. According to the (National Environment Agency, 2018), it states that breathing in asbestos fibres can lead to lung cancer, mesothelioma and asbestosis. Tan (2018) states that “Due to its links to health problems such as lung cancer, its use in buildings was banned in Singapore in 1989, but many earlier structures still contain the substance.” The author also mentions that asbestos is not harmful if they remain unharmed. Once the fibres are released and sniffed, they will be harmful to us. It is worth noting that many buildings in Singapore were built before the 1980s and therefore would contain traces of asbestos in the building. Consequently, it should be indicated that when retrofitting or renovating a building to accommodate good indoor air quality, the materials of the building should be checked before carrying out any works to prevent the inhalation of asbestos.


In addition to asbestos, one other dangerous material emitted from building materials is formaldehyde. According to the (World Health Organization, 2018) formaldehyde may be “emitted slowly from indoor building materials, furniture, paints, and carpets.” Not only is the design and construction phase essential to ensure good indoor air quality, but we must also ensure that the types of furniture that are being used are safe from such chemicals. The (Agency for Toxic Substances and Disease Registry [ATSDR], 2016) mentions that to reduce the levels of formaldehyde in buildings, we can let in fresh air, introduce exhaust fans, and keep temperature and moisture at an appropriate level. Since formaldehyde is in many of our items at home or in buildings, these actions can help to reduce our exposure to them. (ATSDR, 2016) also mentions that another method is to purchase products that have little or no formaldehyde in them. This will help to lower the amount of formaldehyde that we breathe in and leave us with better health in the long run.


Lastly, having poor indoor air quality affects our respiratory health. Indoor air consists of pollutants and the natural outdoor air being brought in through air ducts or entrances. (Environmental Protection Agency [EPA], 2018) stated that the pollutants can irritate the eyes, nose, and throat. It can also trigger headaches and giddiness as well as provoke an asthma condition. The risks of having poor indoor air quality should be made known to convince them to take a more serious approach to ensure the quality of indoor air. (EPA, 2018) also mentions that “Other health effects may show up years after exposure has occurred or only after long or repeated periods of exposure.” The short- and long-term exposure of poor indoor air quality and the exposure to harmful chemicals should be highlighted to companies during the design and construction phase for them to put more thought into the way their buildings are fitted.


Overall the guide would help us achieve an excellent indoor air quality however, it is also important to educate on the health risks of having poor indoor air quality.

References

Agency for Toxic Substances and Disease Registry. (2016, February 10). Formaldehyde in Your Home: What you need to know. Retrieved from https://www.atsdr.cdc.gov/formaldehyde/home/index.html

Audrey, T. (2018, 23 April). Asbestos found on St John’s Island, more than half of the island sealed. The Straits Times, Retrieved from https://www.straitstimes.com/singapore/asbestos-found-on-st-johns-island-more-than-half-of-the-island-sealed

Ministry of the Environment. (1996).  Guidelines for Good Indoor Air Quality in Office Premises. Retrieved from https://www.bca.gov.sg/GreenMark/others/NEA_Office_IAQ_Guidelines.pdf

National Environment Agency. (2018, 7 May). Asbestos Control. Retrieved from https://www.nea.gov.sg/our-services/pollution-control/hazardous-waste/asbestos-control

United States Environmental Protection Agency. (2018, January 29). Introduction to Indoor Air Quality. Retrieved from https://www.epa.gov/indoor-air-quality-iaq/introduction-indoor-air-quality

World Health Organization. (2016, August 4). Indoor air quality risks. Retrieved from http://www.who.int/sustainable-development/housing/health-risks/indoor-air-quality/en/



Monday 8 October 2018

Readers Response Draft 2

In the excerpt Guidelines for Good Indoor Air Quality in Office Premises, Ministry of the Environment (MNV, 1996) stated that buildings should be designed and constructed regarding the pollution which may occur within the building. The Air Conditioning and Mechanical System (ACMV) should be constructed in a manner that reduces the spread of contaminants. MNV (1996) also mentioned that the materials and surfaces of the building should not emit any harmful chemicals, while the placement of outdoor air intakes should not be situated near sources of pollution. Buildings should be constructed in ways that prevent contaminants from entering. To ensure contaminants do not enter, the air ducts should be fitted for easy maintenance and inspections as well as being built with materials that produce less friction. Although the excerpt mentioned that materials and surfaces can add to the poor indoor air quality, it fails to mention how our health will be affected by it and the importance of good indoor air quality as well as how dangerous the emitted chemicals are.

Firstly, having poor indoor air quality affects our respiratory health. Indoor air consists of pollutants and the natural outdoor air being brought in through air ducts or entrances. Environmental Protection Agency (EPA, 2018) stated that the pollutants can irritate the eyes, nose, and throat. It can also trigger headaches and giddiness as well as provoke an asthma condition. The risks of having poor indoor air quality should be made known to convince them to take a more serious approach to ensure the quality of indoor air. EPA (2018) also mentions that “Other health effects may show up years after exposure has occurred or only after long or repeated periods of exposure.” The short- and long-term exposure of poor indoor air quality should be highlighted to companies during the design and construction phase for them to put more thought into the way their buildings are fitted.

Secondly, the excerpt states that the materials and surfaces should not emit harmful chemicals. The harmful materials are not made known to us or in what ways are they a risk to our health. One common material used in construction is asbestos. According to the National Environment Agency (NEA, 2018), it states that breathing in asbestos fibres can lead to lung cancer, mesothelioma and asbestosis. An article by (Audrey, 2018) states that “Due to its links to health problems such as lung cancer, its use in buildings was banned in Singapore in 1989, but many earlier structures still contain the substance.” (Audrey, 2018) also mentions that asbestos is not harmful if they remain unharmed. Once the fibres are released and sniffed, they will be harmful to us. It is worth noting that many buildings in Singapore were built before the 1980s and therefore would contain traces of asbestos in the building. Consequently, it should be indicated that when retrofitting or renovating a building to accommodate good indoor air quality, the materials of the building should be checked before carrying out any works to prevent the inhalation of asbestos.

In addition to asbestos, one other dangerous material emitted from building materials is formaldehyde. According to the World Health Organization (WHO, 2018) formaldehyde may be “emitted slowly from indoor building materials, furniture, paints, and carpets.” Not only is the design and construction phase essential to ensure good indoor air quality, but we must also ensure that the types of furniture that are being used are safe from such chemicals. Agency for Toxic Substances and Disease Registry (ATSDR, 2016) informs that to reduce the levels of formaldehyde in buildings, we can let in fresh air, introduce exhaust fans, and keep temperature and moisture at an appropriate level. Since formaldehyde is in many of our items at home or in buildings, these actions can help to reduce our exposure to them. ATSDR (2016) also mentions that another method is to purchase products that have little or no formaldehyde in them. This will help to lower the amount of formaldehyde that we breathe in and leave us with better health in the long run.

Overall the guide would help us achieve an excellent indoor air quality however, it is also important to educate on the health risks of having poor indoor air quality.

References

Agency for Toxic Substances and Disease Registry. (2016, February 10). Formaldehyde in Your Home: What you need to know. Retrieved from https://www.atsdr.cdc.gov/formaldehyde/home/index.html

Audrey, T. (2018, 23 April). Asbestos found on St John’s Island, more than half of the island sealed. The Straits Times, Retrieved from https://www.straitstimes.com/singapore/asbestos-found-on-st-johns-island-more-than-half-of-the-island-sealed

Ministry of the Environment. (1996).  Guidelines for Good Indoor Air Quality in Office Premises. Retrieved from https://www.bca.gov.sg/GreenMark/others/NEA_Office_IAQ_Guidelines.pdf

National Environment Agency. (2018, 7 May). Asbestos Control. Retrieved from https://www.nea.gov.sg/our-services/pollution-control/hazardous-waste/asbestos-control

United States Environmental Protection Agency. (2018, January 29). Introduction to Indoor Air Quality. Retrieved from https://www.epa.gov/indoor-air-quality-iaq/introduction-indoor-air-quality

World Health Organization. (2016, August 4). Indoor air quality risks. Retrieved from http://www.who.int/sustainable-development/housing/health-risks/indoor-air-quality/en/



Sunday 30 September 2018

Readers Response Draft 1

In the excerpt Guidelines for Good Indoor Air Quality in Office Premises, Ministry of the Environment (MNV, 1996) stated that buildings should be designed and constructed regarding the pollution which may occur within the building. The Air Conditioning and Mechanical System (ACMV) should be constructed in a manner that reduces the spread of contaminants. MNV (1996) also mentioned that the materials and surfaces of the building should not emit any harmful chemicals, while the placement of outdoor air intakes should not be situated near sources of pollution. Buildings should be constructed in ways that prevent contaminants from entering. To ensure contaminants do not enter, the air ducts should be fitted for easy maintenance and inspections as well as being built with materials that produce less friction. Although the excerpt mentioned that materials and surfaces can add to the poor indoor air quality, it fails to mention the importance of good indoor air quality and how our health would be affected by it.

Firstly, having poor indoor air quality affects our respiratory health. Indoor air consists of pollutants and the natural outdoor air being brought in through air ducts or entrances. Environmental Protection Agency (EPA, 2018) stated that the pollutants can irritate the eyes, nose, and throat. It can also trigger headaches and giddiness as well as provoke an asthma condition. The risks of having poor indoor air quality should be made known to convince them to take a more serious approach to ensure the quality of indoor air. EPA (2018) also mentions that “Other health effects may show up years after exposure has occurred or only after long or repeated periods of exposure.” The short- and long-term exposure of poor indoor air quality should be highlighted to companies during the design and construction phase for them to put more thought into the way their buildings are fitted.

Although the excerpt states that the materials and surfaces should not emit harmful chemicals, we do not know what harmful materials are used during construction or how they would be a risk to our health. One common material used in construction is asbestos. According to the National Environment Agency (NEA, 2018), it states that breathing in asbestos fibres can lead to lung cancer, mesothelioma and asbestosis. An article by (Audrey, 2018) states that “Due to its links to health problems such as lung cancer, its use in buildings was banned in Singapore in 1989, but many earlier structures still contain the substance.” (Audrey, 2018) also mentions that asbestos is not harmful if they remain unharmed. Once the fibres are released and sniffed, they will be harmful to us. It is worth noting that many buildings in Singapore were built before the 1980s and therefore would contain traces of asbestos in the building. Therefore, it should be indicated that when retrofitting a building to accommodate good indoor air quality, the materials of the building should be checked before carrying out any works to prevent the inhalation of asbestos.

One other dangerous material emitted from building materials is formaldehyde. According to the World Health Organization (WHO, 2018) formaldehyde may be “emitted slowly from indoor building materials, furniture, paints, and carpets.” Not only is the design and construction phase essential to ensure good indoor air quality, but we must also ensure that the types of furniture that are being used are safe from such chemicals. Agency for Toxic Substances and Disease Registry (ATSDR, 2016) informs that to reduce the levels of formaldehyde in buildings, we can let in fresh air, introduce exhaust fans, and keep temperature and moisture at an appropriate level. Since formaldehyde is in many of our items at home or in buildings, these actions can help to reduce our exposure to them. ATSDR (2016) also mentions that another method is to purchase products that have little or no formaldehyde in them. This will help to lower the amount of formaldehyde that we breathe in and leave us with better health in the long run.


References

Agency for Toxic Substances and Disease Registry. (2016, February 10). Formaldehyde in Your Home: What you need to know. Retrieved from https://www.atsdr.cdc.gov/formaldehyde/home/index.html
Audrey, T. (2018, 23 April). Asbestos found on St John’s Island, more than half of the island sealed. The Straits Times, Retrieved from https://www.straitstimes.com/singapore/asbestos-found-on-st-johns-island-more-than-half-of-the-island-sealed
Ministry of the Environment. (1996).  Guidelines for Good Indoor Air Quality in Office Premises. Retrieved from https://www.bca.gov.sg/GreenMark/others/NEA_Office_IAQ_Guidelines.pdf

National Environment Agency. (2018, 7 May). Asbestos Control. Retrieved from https://www.nea.gov.sg/our-services/pollution-control/hazardous-waste/asbestos-control

United States Environmental Protection Agency. (2018, January 29). Introduction to Indoor Air Quality. Retrieved from https://www.epa.gov/indoor-air-quality-iaq/introduction-indoor-air-quality

World Health Organization. (2016, August 4). Indoor air quality risks. Retrieved from http://www.who.int/sustainable-development/housing/health-risks/indoor-air-quality/en/