International Journal of Advance Engineering and Research Development STUDY ON IMPACT OF TRAFFIC ON ENVIRONMENT STUDY BY AIR QUALITY INDEX

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1 Scientific Journal of Impact Factor (SJIF): 4.72 International Journal of Advance Engineering and Research Development Volume 4, Issue 11, November e-issn (O): p-issn (P): STUDY ON IMPACT OF TRAFFIC ON ENVIRONMENT STUDY BY AIR QUALITY INDEX Likhita Potluri Student, Civil Engineering Department, Dhanekula Institute of Engineering and Technology. Abstract: Air pollution is defined as the presence in the outdoor atmosphere of one or more contaminants (pollutants) in quantities and duration that can injure human, plant or animal life or property (materials) or which unreasonably interferes with the conduction of life and business. Examples of traditional contaminants include sulphurdioxide, nitrogendioxide, carbon monoxide, hydrocarbons, volatile organic compounds(vocs), hydrogen sulphide, particulate matter, smoke and haze. On road vehicles are responsible for a significant and rapidly increasing portion of the air pollution in the urban areas of developing nations. An abstract explanation of air quality index is given. Keywords: Ambient air quality, pollution, transport system, atmosphere, Air Quality Index. I.INTRODUCTION The environmental burden of the transport sector far exceeds the carrying capacity our environment and threatens ecological sustainability and human health. Transport system creates new accessibility levels that encourage changes in land use pattern. Changes in land use, on the other hand, can modify the modern travel demand patterns and include changes in the transportation system. Decentralization of population and employment, itself a function of economic restructuring, increasing per-capita income, and relative reduction of transport prices, increase the attractiveness of areas along the transportation infrastructures. Hence, the exponential growth of car ownership and usage generates emissions. According to the main contributor to local air pollution, transportation directly affects habitat, eco systems, endangered species, and water quality through consumption, fragmentation and replacement of natural cover with impervious surfaces. Additionally, motor vehicles are a major defuse polluting source. As soil and surface water along the highways are polluted from transportation, the nearby receiving waters are contaminated especially by water quality parameters like polycyclic aromatic hydrocarbons (PAH), mineral oil, heavy metals and salt. Urban form also affects travel behaviour, resulting air pollution, global climatic change and noise. Residential and commercial development was indirectly affected including the distribution of employment opportunities. In addition, the transportation options available to link residential and commercial locations influence household travel behavior, including trip frequency, trip lengths and mode of choice. Policy makers have taken counter measures to decrease the negative impacts of transport on air quality, however, attempts to use transfer of policies are generally feeble, and individual policy initiatives are not systematically organized. Additionally, systems providing support for integrated policies are lacking. The data supporting environmental policies are lacking. The data supporting environmental policies are often complex, ambiguous, dispersed across multiple monitoring networks maintained by different organizations. II. The Environmental Impacts of Transportation The issue of Transportation and the environment is paradoxical in nature since transportation conveys substantial benefits, but at the same time transportation is impacting environmental systems. From one side, transportation activities support increasing mobility demands for passengers and freight, while on the other, transport activities are associated with growing levels of environmental externalities. These impacts fall within three categories: 1. Direct impacts: The immediate consequence of transport activities on the environment where the cause and effect relationship is generally clear and were understood. 2. Indirect impacts: The secondary (or territory) effects of transport activities on environmental systems they are often of higher consequence than direct impacts, but the involved relationship are often misunderstood and difficult to establish All rights Reserved 1111

2 3. Cumulative impacts: The additive, multiplicative or synergetic consequences of transport activities, they take into account of the varied effects of direct and indirect impacts on an eco system, which are often unpredicted. Vehicle Emission Factors in grams/km given by ARAI (1998): III. Air Quality index The AQI is an index for reporting daily air quality. It tells you how clean or polluted your air is, and what associated health effects might be a concern for you. The AQI focuses on health effects you may experience within a few hours or days after breathing polluted air. EPA calculates the AQI for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particle pollution (also known as particulate matter), carbon monoxide, sulphur dioxide and nitrogen dioxide. For each of these pollutants, EPA has established national air quality standards to protect public health. Ground-level ozone and airborne particles are the two pollutants that pose the greatest threat to human health in this country. How does AQI work? Think of the AQI as a yardstick that runs from 0 to 500. The higher the AQI value, the greater the level of air pollution and the greater the health concern. For example, an AQI value of 50 represents good air quality with little potential to affect public health, while an AQI value over 300 represents hazardous air quality. An AQI value of generally corresponds to the national air quality standard for the pollutant, which is the level EPA, has set to protect public health. AQI values below are generally thought of as satisfactory. When AQI values are above, air quality is considered to be unhealthy-at first for certain sensitive groups of people, then for everyone as AQI values get higher. Factors effecting Air Quality To predict the pollutants concentration we should know the significant factors that affect the air quality. The various factors that affect air pollutant concentration can be broadly classified as Traffic parameters, Meteorological factors and geological factors. Traffic factors Traffic parameters like traffic volume, composition and vehicles speed affect the pollutant concentration. Traffic Volume Pollutant concentration is directly proportional to the traffic volume. As the traffic volume increases, more vehicles emit exhaust emission in to the air and so the concentration of pollutants increases. Amount of exhaust emission increases with the increasing number of vehicles, so traffic volumes affects the air quality. Vehicle Composition Amount of exhaust emission varies with the type of vehicle. As percentage composition of any type of vehicle increases, the concentration of pollutants increased by it also increases. So this is also an important factor that should be considered in All rights Reserved 1112

3 Vehicle speed For a vehicle that is travelling at an average speed in a stream of traffic, CO and HC emission rates decrease as average speed increases. NOx emission rate, on the other hand, increased with average speed up to certain speed and starts to decrease. This can be contrasted with CO2 emission rate, with decrease up to certain speed, then starts to increase. Meteorological factors Meteorological factors influence the dispersion of vehicular exhaust emission in the atmosphere. Pollutants dispersion and transport will be governed by the meteorological factors like wind speed, wind direction, local atmospheric turbulence, atmospheric stability, surface roughness, ambient temperature, humidity, solar radiation, cloud cover and others. Wind speed Amount of dispersion near roadways is influenced by the wind speed and moving vehicle turbulence wake mainly. These two factors force the pollutants to disperse in horizontal and in vertical directions. Moving vehicles causes two types of turbulence are mechanical turbulence and thermal turbulence. Pollutants concentration decreases with the wind speed increases if the wind speed is below 0.5m/s the considerable dispersion does not take place, so it can be worst condition wind speed. Pollutants concentration will be high at worst case meteorological conditions. Other factors like wind speed, Atmospheric stability, Humidity, Solar radiation, Topographical factors etc. Different methods used to calculate AQI A number of methods are used to calculate AQI in different countries. Some are listed below: 1. IND-AQI 2. USEPA-AQI 3. Average method We mainly discuss IND-AQI broadly for better understanding; IND-AQI Calculation for IND-AQI includes first calculation for sun-indices, which can be made by using following equation (chattopadhyay et al; 2010) q = (V/Vs) Where, q = Quality Rating V = Observed values of the parameter and Vs = Standard value recommended for the parameter q value is considered as Air Quality Index (AQI). Color coding for AQI Ranges (GUFRAN, All rights Reserved 1113

4 AQI Limitations International Journal of Advance Engineering and Research Development (IJAERD) 1. For the real time AQI, the data is fed directly from the analyzers without scrutiny, thus it may not be for statutory purpose. 2. The monitoring and subsequent AQI dissemination involves multiple steps including operation of sensors and analyzers, their calibration, data acquisition at local server, transmission to central database using internet, etc. The functioning of monitoring stations may also get affected due to various technical and operational aspects like long power cuts and maintenance problems. In view of these limitations, it is possible that there may be some disruption in continuous data flow and dissemination. However, in case of breakdowns, necessary actions are initiated immediately for putting the system back into operation within reasonable time period. IV. NATIONAL AMBIENT AIR QUALITY STANDARDS National Ambient Air Quality Standards are legal permits or limits placed on the levels of air pollutants in the ambient air during given period of time. As such, they categorized the allowable level of the pollutant atmosphere and thus define the amount of exposure permitted to the population and ecological system. Table represents the National Ambient Air Quality Standards. The AQI s for the pre monsoon (march-may) and post monsoon (October-November) periods. Awareness of daily levels of air pollution is important to the citizens, especially for those who suffer from illness caused by exposure to air pollution. Further, success of a nation to improve air quality depends on the support of its citizens who are well-informed about local and national air pollution problems and about the progress of mitigation efforts. NATIONAL ABIENT AIR QUALITY STANDARDS S. no Pollutant Time weighted average Industrial, residential, rural Ecologically sensitive Methods of measurements and other area. area(notified by central government) (1) (2) (3) (4) (5) (6) 1. Sulphur Dioxide(SO 2 ) Improved West and gaeke. Ultraviolet fluorescence. 2. Nitrogen dioxide(no 2) 30 Modified Jacod & Hochheiser(Naarsentle) Chemiluminescence. 3. Particulate matter(size less than 10um) 4. Particulate matter(size less than 2.5um) 5. Ozone(O 3 ) 8 hours 1 hour 1 1 Gravimetric TOEM Beta attenuation Gravimetric TOEM Beta attenuation -uv photometric -chemilminescence -chemical All rights Reserved 1114

5 SCOPE FOR FUTURE WORK More detailed surveys have to be conducted taking into consideration the locations of intersections and consequent queuing situations that often arise on the road network. Similarly surveys to be conducted in different seasons and at locations deeper inside, so as to determine the extent of the spread of pollution. Surveys should also be conducted in many other cities to develop a proper model for the prediction of the quality. By projecting the traffic parameters and the air quality levels for future time period, the model can be used for forecasting. REFERENCES 1. A study on air pollution and its impact on human health in Chennai city By P. Thilagaraj, R.Ravinder, R.Kesavan. 2. Ambient Air Quality of an Industrial Estate By Mandi Gobindgarh 3. Traffic Engineering and Transportation Planning By Kadiyali All rights Reserved 1115