Air Quality Deterioration – Causes and Defects
Air is the mixture of gases and other particles which occupy the space around us and which are usually transparent in nature. Such an intangible substance can be contaminated when pollutants are mixed with its original contents. This composition of the contents of the air around a specific individual, community, location, etc in terms of the amount of pollutants in it is referred to as air quality. It has been observed through ages that the air quality on earth (in general) has been deteriorating (Seinfeld, 2016). This is due to a range of factors like burning of fossil fuels, release of ammonia due to agriculture, the exhaust waste from industries and factories, the dust and chemicals which are released into the air due to mining activities, a variety of domestic tasks also contribute towards air pollution like painting and cleaning, etc. NASA is known to keep a tab on the earth’s air quality. It uses three satellites to do this and they are called as Aqua, Suomi-NPP and Terra. These are placed in the earth orbit and help in analyzing the extent of air pollution. The Multi-Angle Imager for Aerosols (popularly referred to as the MAIA) is also a tool developed by the NASA which will also be used to check the extent of pollutants in the earth’s atmosphere. This instrument is designed to fly as a part of a future space mission. This will also help the scientists on earth interpret the quantity, size and makeup of the aerosols which are present in the globe’s atmosphere (Devinny, 2017). This will in turn help in creating a trend analysis and at the same time will facilitate comparison with previous year’s air quality. These can also be read alongside the increase in health issues so that a linear relationship can be firmly established between the increase in harmful substances in air and the condition of health (of human beings, animals and plants).
According to (Heck, 2016), the effects of such air contamination are also very widespread. They can be viewed from an individual point of view as well as a whole community point of view. For instance, on an individual level people living in a vicinity where the air quality is very poor are more open to heart and respiratory diseases. Cancer can also be an effect of extensive pollution. Asthma and pneumonia are common in children (below the age of fourteen) who are exposed to such air pollutants on a regular basis.
The release of a range of harmful chemical gases into the open atmosphere has led to global warming. This means that the average temperature on earth is increasing. This increase in temperature is leading to the melting of the globe’s ice capes in turn increasing the water levels of the sea. A lot of animals and plants species will have to lose their natural habitat if this happens.
Severe case of air pollution (that is the release of toxic gases like sulfur oxides and nitrogen oxides) into the atmosphere at the time of burning fossil fuels may facilitate acid rain. When these pollutants are mixed with the water content in the atmosphere they tend to come down to earth in the form of rain. Such rain is extremely acidic in nature and can affect crops, animals and also human beings.
A rare condition (will not be so rare in the future) called Eutrophication exists when release of large amounts of nitrogen into the atmosphere forms a layer on the ocean’s surface in the form of algae. This algae is very harmful to the aquatic life living in the vicinity (includes fishes, animals and sea plants). Such an algae is usually green in color and affects the quality of water (Lelieveld, 2015).
The depletion of the ozone layer can be considered as the most drastic effect of deterioration of air quality. In simple terms, ozone is the layer that is present in the globe’s stratosphere (Lelieveld, 2015). This layer protects the earth from the toxic Ultraviolet rays (UV rays) that try to enter. These ultraviolet rays when come in contact with the human skin will affect it in a negative manner. Usually eye and skin based problems are expected to be experienced by people who come in contact with such ultra violet rays. A specific kind of chemicals like hydro-chlorofluorocarbons and chlorofluorocarbons (CFCs) are the reason for ozone layer becoming thin.
Other reasons for depletion of air quality can be because of the harmful substances that come out of volcanos, smoke from the burning of inflammable substances, methane due to digestion in cows, etc.
Solutions to better the Air Quality
Many researchers and scholars across the globe have been emphasizing on the need to work towards replenishing the air quality as it is no longer an option but a need in order for everyone on earth to survive. Different governmental agencies and non-governmental agencies across countries have come up with various ideas as to how to get this vision put into execution (Di, 2017). Some of the common solutions that the United Nations agreed to include emphasis on the use of public mode of transportation. This ensures that every individual doesn’t come in their own personal vehicle and prefer a carpooling service or a bus or a metro. By doing this a great deal of fuel is conserved.
Another effective solution is to promote the adoption of the 3Rs concept in daily life. The 3Rs stand for Reduce, Reuse and Recycle (Di, 2017). By doing this, less fossil fuels will be consumed and the burning or dumping of waste products won’t even lead to any sort of pollution at all.
It is a known fact that a shift to renewable sources of energy from the tradition non-renewable sources of energy like burning of coal for generating energy. Renewable sources of energy include the use of wind, solar or geothermal energy which do not affect the environment or its air quality in any fashion.
Air Quality in India
It is obvious that maintaining a huge country with vast population like India is not an easy task. (Arora, 2018)The air quality in India is at a serious point and needs immediate solution. The main reason for decreased air quality in India is due to its age old practices. Since a very long time, Indians have been accustomed to use firewood for cooking and a range of other domestic purposes. This is kind of the culture in which Indians have been living in since time immemorial. Very little emphasis on air pollution is available in its ancient texts like the ‘Vedas’ and ‘Bhagavad-Gita’. Since recently not all residents of India were made aware of this increasing threat. Even today most of rural India is entirely unaware of the kind of threat that the country faces. There are a range of reasons that contributed to air pollution in this ancient country like burning of waste, transportation within the domestic borders, use of diesel generators, the extent of small scale, medium scale and large scale industries in the country, use of coal and firewood for domestic cooking, construction and dust.
(Arora, 2018)It is established that thirteen out of the globe’s top twenty cities with greater levels of air pollution are located in India. The country’s capital – New Delhi is declared as the world’s most polluted city in 2014. The other most polluted cities in India are – Patna, Jodhpur, Patiala, Jaipur, Gurgaon, Srinagar, Muzzaffarpur, Agra, etc. The most brutal environmental event has been marked in New Delhi recently in 2016 when the Great Smog of Delhi covered the entire vicinity with thick blanket of smog making it difficult for its residents to breathe.
Rural India is also partly responsible for the increasing air pollutants in the atmosphere. The seasonal burning of crops is a major contributor to air pollution in the form of smog and smoke. They also use a variety of items for cooking and staying warm like firewood and coal which also contribute to deterioration of air quality. On the other hand, urban pollution is mainly caused due to transportation and industrialization. Fuel Adulteration is the main reason for pollution caused by transportation. Increasing fuel prices is the reason why some people in India resort to such practices (Arora, 20118). They often mix kerosene into diesel and other related products. Such fuels increase emissions like carbon monoxide, hydrocarbons, particulate matter and nitrogen oxides, benzene and polyaromatic.
(Greenstone, 2017) The emission of greenhouse gases like carbon dioxide is also major in India. This has led to a range of health effects for the people of India. Some of such health concerns include general reduction in human life span, cancer, eye related infections, and skin related infections, general health issues, tuberculosis, lung infections, breathlessness and asthma. The other impacts on the country are increase in global warming effects, loss of wildlife and plant species, leads to other kinds of pollution, melting of Himalayas, increase in river water levels, etc.
General Awareness about air quality
Very little literature is available as to how aware are today’s consumers with regard to air quality and the possible effect the use of a particular product is going to have on the air they breathe in every day. Though people have been made abundantly aware of the concept of pollution, these are just theories (topics like pollutants, acid rain, global warming, deforestation, etc) until people are equipped with the resources to put such concepts into reality. (Sagar, 2016) The gap between knowledge and implementation needs to be closed in order to reduce air pollution in India and at the same time increase the quality of air in the country. In order to do this, consumers of technology should be made aware of the need to use air filters in their lives. This should be recognized as one of the main element which contributes towards the filtering of air in air cleaning technology based products. Such equipment will help in creating a better area to breathe in and at the same time purifies the existing atmospheric condition.
Before working on such air filter technology it is important to analyse how a potential consumer is likely to react and whether or not he or she will be keen on using such a system. The buyer behavior needs to be analyzed before deciding on the characteristics of the air filter and how it needs to be designed.
Unified theory of Acceptance and use of Technology (UTAUT)
Many startups in the last decade have popped up in the Indian market with innovative solutions which would help in curbing the problem of air pollution in India. Therefore, this market is still at its nascent stage and has a promising future for people who would want to invest in such startups. Promoting or spreading awareness about the need to ensure reduction in air pollutants is the best way to solve this issue. An informed consumer would definitely search for products which will help him or her make a positive print on the country. Only if a demand is created in the market will people want to cater to those demands which will in turn bring in the supply part of the equation.
Air Pollution Control Equipment
(Schenelle, 2015) It is a common phenomenon that air pollution sources in general are broadly classified into two blocks – natural and human made causes. Natural sources of air pollution usually include natural disasters like forest fires and volcanic eruptions. Human sources of air pollution can be again classified into stationary causes and mobile causes. Stationary air pollution causes are mostly in relation with industries like power plants, pharmaceutical factories, chemical industries, etc. Mobile air pollution causes are with reference to vehicles (automobiles, trains, airplanes, etc) which are mobile and as a result of it adds to air pollution in the form of smoke, etc. Alternatively these can also be classified on the basis of the amount of pollution they cause. For instance, emission of less than 10 tons of an individual pollutant can be categorized as a minor source of air pollution. Any entity that releases more than 10 tons of an individual pollutant into the air can be categorized as a major source of air pollution.
The Clean Air Act (CAA) was introduced by the Environmental Protection Agency (EPA) which is responsible for imposing restrictions on the above mentioned types of air pollutants with an intention to increase the air quality and also reduce the amount of air pollutants in the atmosphere. The Environmental Protection Agency (EPA) has identified three types of air pollutants – these are greenhouse gases, air toxics and general air pollutants (Dupont, 2017).
The Environmental Protection Agency has also released a set of standards that are expected to be adhered by industries while being responsible for any of the above three categories of air pollutants. One of the major consideration that this agency pressurizes its industries to adopt is the installation of a range of air pollution control equipment and try to indulge them in their daily operations. By doing this, a culture of being responsible towards the atmosphere around us will be smoothly inculcated in every day routine.
The kind of air pollution control equipment that is required to be used by an industry or a mobile vehicle varies significantly and the consumer must ensure that he or she has adequate prior knowledge regarding the regulatory requirements as well as the application part of it. Almost every step of a manufacturing process contributes some way or the other towards polluting the air right from sourcing the raw materials, manufacturing the product, maintaining the premises and ensuring the machinery under use is repaired regularly, to distribution of produced goods (Sherman, 2016).
Air pollution control equipment is commonly used to refer to a wide array of equipment and technologies that are present in an industrial scenario or in an automobile scenario. The release of dust, vapor and chemicals into the atmosphere can be managed to a great extent if control equipment can be effectively fitted into the wide list of industries that were earlier responsible for deterioration of air quality in their vicinity. It is important to note that the prime source of exhaust (that is from where such harmful emissions are released into the air around us) needs to be identified and managed in an efficient manner. Usually a variety of blowers and fans are used to vent out the excess unwanted chemical gases, dust or vapors.
There are three primary processes which can be adopted by every responsible industry in order to try to save the atmosphere around them. These are popularly referred to as Collection, Conversion and Combustion (Godish, 2019).
Some of the different equipment which is being used in the industrial sector to control air pollution is bio filters, catalytic reactors, incinerators, mist collectors, electrostatic precipitators, cyclones, air filters, and scrubbers. Scrubbers are the easiest way of ensuring that they contribute their bit in reduction of air pollution by simply employing a physical process of scrubbing the air exhausts that is blowers or fans which are installed at the premises of a manufacturing unit. They can be broadly classified as wet scrubbers and dry scrubbers. Wet collectors (also known as wet absorption) are the scrubbers which usually use liquid for the purpose of scrubbing the surface of the gas emission ventilators. Some gases are soluble in water and this is the best way to clear such air pollutants. One of the latest technologies that are installed in industries enables harmful gases to pass through a liquid content. This liquid content helps in removing the toxic pollutant particles from the stream of gases before leaving it into the atmosphere (Brennan, 2018). Dry adsorption scrubbers also known as dry scrubbers. Chemical gases which are meant to release out of the manufacturing unit’s exhaust often flow in streams. These streams are brought in contact with neutralizing chemical components (like sodium carbonate). These chemical agents interact with the gases (these are usually made of the opposite chemical characteristic for instance, if the gases are basic in nature, the neutralizing chemical agent would be acidic) and neutralize the overall impact of the harmful exhaustion. Such special agents are then scrubbed away by the dry scrubbers as discussed above. Such special agents are collected and then washed and held for reuse in the future. Usually the nature of these pollutants is acidic and hence most of the neutralizing agents being used are obviously basic in nature.
Air filters are the most common and simple ways of filtering toxic components from the air by installing a variety of materials which play the role of filters between the manufacturing unit chemical gases tract and the external environment. These materials are usually made out of ceramic, sintered metal or various kinds of fabrics, etc. These act as a translucent medium for the gases to pass through, and while passing through the toxic substances tend to get blocked within the layers of these mediums. A collection of chemicals, microbes, pollen and dust are the usually components which get blocked in the medium and are collected and disposed of properly before releasing into the environment. Such application of devices are not just restricted to industrial establishments but also apply to domestic households, automobiles, and commercial establishments. When considering industrial establishments alone, there are three types of air filters – Cartridge dust collectors, fabric filters and HEPA filters (Borup, 2018).
Cyclones are another method of controlling the air pollutants and their emission into the atmosphere. These are also known as cyclone dust collectors. Though the whole process is similar to air filters, they can be differentiated on the basis of the model of application. This equipment uses centrifugal force instead of installing filtering mediums in order to filter the harmful emissions from the manufacturing unit before letting it out into the air. The chemical gas stream is made to flow through a circular path where large particles hit the walls of the equipment and drop them into a collector. The rest of the gas is let out of the cylinder into the external open air. The toxic substances which have dropped into the collector are then collected and disposed of in an efficient and environmentally responsible manner. The efficiency of employing this mechanism depends on how big or small the diameters of these particulates in the air are (Crane, 2015). The only limitation of this approach is that the smaller air pollutants are often ignored in this model. Hence, industries usually equip other air pollution control equipment along with cyclones in order to deal with such minute particles of toxic substances as well. These usually take the form of air filters or scrubbers.
So far the most effective way of controlling air pollution is adopting the use of Electrostatic Precipitators – ESPs in their operations. The working model of ESPs involve the use of charging electrodes. These charging electrodes are place in relation to collectors. The stream of toxic air is made to pass through a path where high static electrical difference is created between the collectors and electrodes. The particles in the gas stream are introduced to electric charge as a result of it. Such charged particles are attracted towards the collector. All such harmful substances are regularly collected and periodically cleaned either manually or through passing of water through the collector.
Most people misunderstand vapor and other moisture related pollutants to not be harmful. Whereas in reality, they are equally toxic from a global point of view. Hence, the use of mist collectors guarantees up to 99.9 percent of efficiency. This is because the components of vapor and moisture in air are very different from the rest of the particles, and the use of fine mist collectors (filters) can easily be able to separate the fine liquid components in the gas stream from the rest. These face quite a few limitations when it comes to their practical application. For instance, they cannot process the filtration of gas streams above the temperature of one hundred and twenty Fahrenheit. At the same time if the gas stream is also mixed with certain large particles (particles with bigger diameter), they would be unnecessarily blocked in the mist collector (as they are not made for them) and thus also hamper the effectiveness of the mist collector from collecting water related pollutants like harmful vapors and moisture related substances.
(Chowkwanyun, 2019) Incinerators are relatively newer technologies which use the concept of combustion to reduce or control the impact of air pollution in an industrial setup. These equipment usually break down complex substances involving hazardous air pollutants, hydrocarbons, etc by burning them and converting them into less harmful byproducts like nitrogen, carbon dioxide and oxygen. These resultant pollutants are also usually managed by adopting any of the above mentioned air control equipment like either scrubbers, air filters, cyclones, etc. The main limitation of this equipment is that it doesn’t guarantee hundred percent control over the air quality or the reduction of air pollutants in the atmosphere. Some of the most used incinerators are – catalytic oxidizers and thermal oxidizers. Thermal oxidizers are used on chemical gases like odorous fumes, hydrocarbon elements and VOCs. On the other hand, catalytic oxidizers involve the usage of artificial catalyst beds to help the process of incineration.
These are air quality control systems which are introduced in a manufacturing setup (especially in industries which run in relation to fossil fuel and it’s burning) with the aim of reducing or managing the impact of releasing nitrogen oxide into the atmosphere. Ammonia is the agent which is used in this kind of equipment which open brought in contact with the toxic gas nitrogen oxide reacts with it and splits it into two different components oxygen and nitrogen. Other air filter equipment are used alongside these to reduce the impact of pollution caused by the release of nitrogen and oxygen individually. Around ninety percent efficiency is expected out of this technology. These are found to be fitted in automobiles. The catalyst which is used in this process is very costly and often is believed that this causes the costs to outweigh the benefits derived out of it.
These have a similar aim as the above mentioned air quality control equipment that is to manage the amount of pollutants that is released into the air by a specific entity. The main difference between this technology and the others is that here, microorganisms are put into use while filtering out the pollutants and its particles from the gas stream which is produced. Variety of fungi and bacteria is put to use in this model. The expected efficiency rate of these technologies is ninety eight percent. These microorganisms help in degrading the gas stream and separating liquid-soluble (mostly water is considered) elements from the rest of the stream.
Industries in India
The country’s pollution has been increasing exponentially since the last five decades. The government of India pretty soon after its independence in the 1947, realized the need to work on creating an efficient model that keeps a track about the amount of pollution that is caused by the country. In 1967, for the very first time they started monitoring the quality of air around them (Jaing, 2015). The National Environmental Engineering Research Institute – NEERI was the responsible entity which was designated on this task. Apart from this institute there is another central body which also started working towards the same goal but after twenty years of the incorporation of NEERI. They brought in the National Air Quality Monitoring Program (NAMP) and National Air Monitoring Green Growth. As a part of these initiatives, the members of the body were able to identify four most toxic pollutants that are majorly released by the factories in India. These four elements are the ones believed to be affecting the atmosphere in India the most. These include – Respirable suspended particulate matter – RSPM, Suspended particulate matter (SPM), nitrogen oxides and sulfur dioxide. The initiatives are not restricted towards only these four elements but are also applicable to few others like polycyclic fragrant hydrocarbons, hydrogen sulfide, alkali, etc. The only difference is that the former ones are focused more onto.
The leading industries in terms of polluting air in India can be categorized into three – automobiles, thermal power stations, and the manufacturing factory chimney waste. The automobile sector in India is increasing at an alarming rate. Though it is a good thing that the country is benefitting from a large contribution to its gross domestic product and also its citizens who are now provided with luxury and other services in the form of vehicles, it has a huge impact on the environment. It is due to components of automobiles like fuel tank, crank case, carburetor and the entire framework pollution is caused. The fumes which are a result of the production of these contain unburnt lead oxides, nitrogen oxide, carbon dioxide and hydrocarbons. In case the nature of the fuel is unstable, evaporation from the tank is possible and this in turn results in the release of hydrocarbons.
Most of electricity generation in India is based on its thermal power plants. These are warm power plants which are often even harmful to work at. West Bengal, Andhra Pradesh, Madhya Pradesh and Uttar Pradesh are four states on which the country depends for electricity supply round the year. Though some parts of India are supplied with electricity generated out of hydel power plants (at dams and reservoirs), these form a very small portion of the whole picture. The use of coal and other substances in this process of combustion leads to the production of sulfur dioxide, hydrocarbons and fly powder which are tremendously harmful to the planet (Zeng, 2019).
The most common way in which industries in India contribute towards air pollution is by releasing excess waste through chimneys into the air. This is the primary reason why the Indian government made it a point to locate all industrial estates outside major towns and cities with the intention of not polluting the air around its citizens directly. It is observed that the main contaminants of air that are released in this manner contain nitrogen oxides and Sulphur dioxide. Petroleum factories (refineries), cement industries, hot blend factories, stone crushers, food industries, fertilizer factories, etc are the kinds of industries which actively contribute to air pollution in India. The country has been actively trying to find alternatives for these products. It has also introduced a range of subsidies and other benefits for people who have an intention of serving the country in a better way that is far away from destroying its natural environment in any form. For instance, the manufacturing of plastics has been discouraged in the country to a great level.
A deep analysis at the kind of air pollutants that are present in abundance in the Indian atmosphere and the kind of industry from which it is probably emitted has led to the following conclusions (Siegel, 2016) –
Air Pollution in the Capital City of India
New Delhi has been the most polluted city in India for a long while till now. A mere connecting flight experience in this city will make any outsider feel the difference in air quality in their first breathe of the air in New Delhi. As people establish, it is not just the high rates of vehicles that are visible on the roads of the capital city that is contributing to air pollution in this area. The usage of Liquefied petroleum gas – LPG by the domestic households is also a major contributor for air quality depletion here. This is the case only in New Delhi are in other urban parts of the country. On the hand, people and domestic households in the rural India (which holds majority of the population of India) contribute to the country’s air pollution not by using liquefied petroleum gas – LPG like the urban families but instead involve in practice like combustion of firewood for the purpose of cooking (Wight, 2018). They also use firewood and in some cases burn coal also in order to keep themselves warm, or heat water for daily purposes.
According to studies by famous institutions like the IIT (Indian Institute of Technology) and IIM (Indian Institute of Management), the prime way of reducing pollution in these areas is by regulating the use of personal vehicle movement. The shift towards electric vehicles is also foreseen by many experts. The government of India is also aiming at being supportive to the cause by ensuring that recharge booth will be constructed by the government and be made available at nominal rates with the intention of encouraging its citizens to shift to such choice of vehicles. Many private companies in and outside India are also very committed to this objective and are ready to invest huge amounts (some already have invested) into research and development. Such research and development is expected to be held with an intention to design and create new and better fuel efficient vehicles for Indian use. Currently the reasons why Indians are not preferring to buy this idea is because of the reduction in performance of these vehicles as compared to ones which run of petrol or diesel, and also the lack the availability of the recharge stations for the car batteries.
Arora, R. (2018). Assessment of the Mortality Burden Associated with Ambient Air Pollution in Rural and Urban Areas of India (Doctoral dissertation, University of Southern California).
Borup, M. B. (2018). Pollution Control for the Petrochemicals Industry. CRC Press.
Brennan, T. J. (1973, March). The Use of Fabric Filters in Air Pollution Control. In ASME Citrus Engineering Symposium (Vol. 99601, pp. 54-58). American Society of Mechanical Engineers.
Chowkwanyun, M. (2019). Two Cheers for Air Pollution Control: Triumphs and Limits of the Mid-Century Fight for Air Quality. Public Health Reports, 134(3), 307-312.
Crane, K., & Mao, Z. (2015). Costs of selected policies to address air pollution in China.
Devinny, J. S., Deshusses, M. A., & Webster, T. S. (1998). Biofiltration for air pollution control. CRC press.
Di, Q., Wang, Y., Zanobetti, A., Wang, Y., Koutrakis, P., Choirat, C., Dominici, F. and Schwartz, J.D., (2017). Air pollution and mortality in the Medicare population. New England Journal of Medicine, 376(26), pp.2513-2522.
Dwivedi, Y. K., Rana, N. P., Jeyaraj, A., Clement, M., & Williams, M. D. (2019). Re-examining the unified theory of acceptance and use of technology (UTAUT): Towards a revised theoretical model. Information Systems Frontiers, 21(3), 719-734.
Dupont, R.R. and Ganesan, K., (2017). Air Pollution Control Equipment. Unit Operations in Environmental Engineering, p.145.
Jiang, X., Hong, C., Zheng, Y., Zheng, B., Guan, D., Gouldson, A., ... & He, K. (2015). To what extent can China’s near-term air pollution control policy protect air quality and human health? A case study of the Pearl River Delta region. Environmental Research Letters, 10(10), 104006.
Godish, T. (2019). Indoor air pollution control. CRC Press.
Greenstone, M., Harish, S., Pande, R., & Sudarshan, A. (2017, July). The Solvable Challenge of Air Pollution in India. In India Policy Forum.
Heck, R. M., Farrauto, R. J., & Gulati, S. T. (2016). Catalytic air pollution control: commercial technology. John Wiley & Sons.
Lelieveld, J., Evans, J. S., Fnais, M., Giannadaki, D., & Pozzer, A. (2015). The contribution of outdoor air pollution sources to premature mortality on a global scale. Nature, 525(7569), 367-371.
Sagar, A., Balakrishnan, K., Guttikunda, S., Roychowdhury, A., & Smith, K. R. (2016). India leads the way: A health-centered strategy for air pollution.
Schnelle Jr, K. B., Dunn, R. F., & Ternes, M. E. (2015). Air pollution control technology handbook. CRC press.
Seinfeld, J. H., & Pandis, S. N. (2016). Atmospheric chemistry and physics: from air pollution to climate change. John Wiley & Sons.
Siegel, F. R. (2016). Mitigation of dangers from natural and anthropogenic hazards: Prediction, prevention, and preparedness. Springer.
Sherman, P. E. (2016). Air Pollution Control Systems.
Wight, G. D. (1994). Fundamentals of air sampling. CRC press.
Williams, M. D., Rana, N. P., & Dwivedi, Y. K. (2015). The unified theory of acceptance and use of technology (UTAUT): a literature review. Journal of enterprise information management.
Zeng, Y., Cao, Y., Qiao, X., Seyler, B. C., & Tang, Y. (2019). Air pollution reduction in China: Recent success but great challenge for the future. Science of the Total Environment, 663, 329-337.
Earn back money you have spent on downloaded sample
To export a reference to this article please select a referencing stye below.
Urgent Homework (2022) . Retrive from http://www.urgenthomework.com/sample-homework/a-study-of-perception-on-air-quality-information-in-india
"." Urgent Homework ,2022, http://www.urgenthomework.com/sample-homework/a-study-of-perception-on-air-quality-information-in-india
Urgent Homework (2022) . Available from: http://www.urgenthomework.com/sample-homework/a-study-of-perception-on-air-quality-information-in-india
Urgent Homework . ''(Urgent Homework ,2022) http://www.urgenthomework.com/sample-homework/a-study-of-perception-on-air-quality-information-in-india accessed 23/01/2022.