Technology environment and society Note by Dr. k.n. Dulal

Technology, Environment and Society Bachelor of Engineering (B.E.) Year/Part: IV/II Program: Computer and Electronics Prepared by: Dr. K.N. Dulal

Definitions Technology According to Webster’s dictionary, technology is defined as a description of arts. General definition of technology Technology is technical means, which involves the systematic application of organized knowledge, and tools and materials for the extension of human faculties. Technology is the source of change in society. Technological innovation • Creative. feasible ideas • Practical application • Diffusion through society

Environment Environment is defined as the immediate surroundings which supports life and sustains various human activities. The surroundings comprises of • Biotic or living things: plants, animals, microorganisms • Abiotic or non-living things: land, water, air etc.

Society Society is people living together in communities.

Chapter 1. Brief History of Technology Beginnings (from beginning to 3000BC) Universe: Evolution theory: Big bang theory, 10 to 20 billion years ago Solar system: Sun at the centre and eight planets, age of sun: about 5 billion years Earth and life: some facts

• • • •

Third planet that orbit the sun Formed from cloud of dust and gas drifting through space about 4.6 billion years ago. First primitive life: algae and bacteria appeared around 3.4 billion years ago. Human being o Separation of human lineage from primates: about 2 million years ago. o Modern human (homosapiens) appeared in Africa around 100,000 years ago. o Beginning of human civilization: about 5000 years ago

Stone Age • Age prior to the beginning of civilized society (up to 3000BC) • Tools: stone, wood, animal bone, horn • No use of metal tools • Potter’s wheel (around 6500BC) • Nomadic culture: Humans moved from one place to another place searching for the foods • At the end, more settled

1.1 Civilizations between 3000BC to 1660 AD a. First civilizations (3000 BC to 1100 BC) Bronze Age • Cupper: First discovered metal • Bronze (Mixture of Cu and Tin): Second discovered metal Sequences • By 4000BC, quasi-civilized society in Egypt and Mesopotamia • Around 3000 BC: human civilization began. Civilizations a. Egyptian civilization: in the valley of Nile b. Sumerian civilization: in plain of Tigris and Euphrates in Southern Mesopotamia c. Assyrian civilization: in upper Tigris d. Maya civilization: in Peru e. Civilizations in China f. Civilizations in India: Flourishing of Hindu religion in India, Vedas and Upanishad g. First Babylonian empire • Semitic (dark white or brownish people from Syria and Arabia) people conquered Sumeria by 2750BC, made Babylon the capital • Hammurabi: 6th king of Babylonia, made code of laws, which is first written code of laws h. Jews (Hebrews) • Semitic people settled in Judea long before 1000 B.C. • Hebrew Bible (Old testament) around 1000 BC • Prophets of Jews: Abraham, Mosses • Solomon: king of Hebrew Monarchy, builder of the first temple in Jerusalem i. Spreading of Aryans • Tribes of fair and blue eyed Nordic race • Spread from central Europe to Asia Inventions/ Developments during Bronze age

• • • • • • • • • •

Discovery of bronze, Metal working, Glass working Invention of Potato in Peru Animal domestication: cattle, sheep, goats and asses Cultivation Navigation technology Techniques of Yoga and meditation Invention of first writing system (wage-shaped) by Sumerians Invention of picture writing system by Egyptians Invention of Semitics writing system by Hebrews by mixing Sumerian and Egyptian writing o All other major languages, e.g. Sanskrit, Latin, Greek, French, Arabic etc. derived from Semitics Construction of cities, temples, tombs, systematic irrigation, war chariots

b. Iron Age (1100 BC to 500 AD) •

First use of iron for implements and weapons.

Historical sequences in Iron Age a. Gautam Buddha (nearly 550 BC) b. Confucius and Lao Tse in China (around 6th century BC) c. Emperor Ashoka in India: spread Buddhism to Kashmir, Persia, Ceylon, China and Alexandria (capital of Roman empire) d. Jesus Christ e. Victory of Aryan: from 900 to 600 BC over the whole ancient world: Semitic, Egyptian, Greek, India except China f. Greek civilization Greek people: trades, travelers, enthusiastic Greek Philosophers ƒ Thales, Pythagoras, Socrates, Plato, Aristotle, Ptolemy, Euclid, Archimedes ƒ Plato, Aristotle: most prominent Plato (400 BC): Mathematics and Astronomy o Plato published a book named Utopia which deals with the plan to form a different and better than the existing one. Utopian society defines the process of development in three steps: plan, public, and law. Aristotle (300BC) o Gathering information, analyzing and solving the problem in a systematic way (beginner of science). o Father of history and founder of political science g. Roman civilization ƒ Autocratic Roman empire in Europe (from 200 BC) ƒ No scientific development ƒ Focus of Romans on health and well being h. Spreading of Mongolians all over the world by two century BC. Inventions/technological development during iron age • Prosperous China: Construction of great wall, invention of paper, tea, wood block printing • Development of Iron technology • Literature: around 200 BC

c. The middle ages (500 to 1450) Sequences of middle age a. prophet Muhammad (600AD) • Dictated a book, Koran, which he declared was communicated to him from God • Beginning of Islam religion b. Arab’s supremacy ƒ Powerful Arabian empire: Arabians were Masters, Europeans pupils ƒ Stretched from Spain to China ƒ Learnt paper and printing from China ƒ Came in touch with Indian Mathematics ƒ Translated Greek literature c. Mongolian’s conquest ƒ Jengis Khan (1200 AD): conquered China, Turkmenistan, Persia, Armenia, part of India down to Lahore, South Russia and Hungary ƒ Ogdai Khan: completed the conquest of whole China and all Russia (former Soviet Union) ƒ Other emperors: Mangu Khan, Kublai Khan, Hulagu Khan d. Mogul dynasty in India (Mongolian: Mogul in Urdu) ƒ Baber: Descendent of Mongolian, conquest India ƒ Akbar: completed the conquest of whole India f. Renaissance of Europe: Intellectual revival ƒ From 1200 AD: revival of European intelligence ƒ Commercial and industrial activities boomed in northern and central Italian cities (1250) ƒ Development of cities ƒ Growth in trading ƒ Arabian literature and scientific experiments translated into common language ƒ Roger Bacon: father of modern experimental science, deserves prominence in our history second to that of Aristotle ƒ University at Paris, Oxford, Bologna and other cities ƒ Exploration: Marco Polo, Columbus, Vasco De Gama ƒ By 1500 AD, Europeans became intellectual and material leader Inventions/Developments in middle age a. From Arab world • Great advances in Math, Physics, Chemistry and Medical science • Spreading of Arabic figure invented by Hindus, sign zero invented by Arabs • Metallurgical and technical devices made by Arabs b. From Mongolian • Opening of silk road by Mongolians to link Asia and Europe for trade c. From renaissance of European • Good quality paper and printing • Advance in education and science • Mariner’s compass

d. Towards the modern world (1450 to 1660) Sequences a. Period of growth for scientific knowledge • Birth of many scientists: Leonardo Da Vinci, Galileo, Kepler, Blaise Pascal, Robert Hooke, Newton: Influenced the world of science b. Age of mechanical revolution • Process of mechanical invention and discovery • Technological development due to organized science • Mechanical power and the machine doing the labour work of human and animals c. Advance in popular education throughout the Westernized world Inventions/Developments • Invention of saw mill, microscope, telescope, clocks

1.2 The Industrial revolution, early days (1660 to 1815) The mechanical revolution was followed by the industrial revolution. Sequences • Age of social and financial development • Scientific discoveries, application of science and technology • Began from England around sixties of seventeenth century after the invention of steam engine by James Watt • Mass production, factory system and improved machinery and machine tool • Further advancement due to the invention of electric power • By the early 19th century, industrial revolution spread to other parts of Europe Inventions/Developments • Friedrich Staedtler founded a pencil factory in Nuremberg, Germany. o Staedtler Mars GmbH & Co. the oldest manufacturing companies in the world. • Many books on industrial development • water-powered mill • Processing of iron from ore using blast furnace technique in 18th century o Rolled iron sheet in 1728 and rolled rods and bars in 1783. • First modern steam engine by James Watt (1765) • Use of steam power: cotton factory, boat, ship • First locomotive by Trevithick in 1804 • Electricity: Investigation of Franklin, Volta, Faraday and Galvani • Chemistry advanced • American System of Manufacturing (1813) • Steam powered train

1.3 The Industrial revolution in maturity (1815 to 1918) Sequences a. By early 19th century, science has come to be revolutionized. Prominent scientists e.g. Alfred Nobel, Faraday, Graham Bell, Charles Darwin, Albert Einstein b. Age of engineering: Technological development Inventions/Developments • Electric motor by Faraday (1821) • First railway between Stockton and Darlington in 1825 • Discovery of electric telegraph in 1835, first under seas cable laid in 1851 between France and England • Analytical engine by Charles Babbage (1834), father of computer • Steam hammer (1838) • Bessemer process (1856) and open hearth process (1864) for processing of iron and steel • Telephone by Alexander Graham Bell (1876) • Steam turbine (1884) • Petrol car by Carl Benz (1888) • Internal combustion diesel engine by Rudolph Diesel (1893) • Wireless telegraphy by Marconi (1896) • Medical science and agricultural science advanced • In 1903 testing of the first air craft by Wright brothers in the USA, availability of aeroplane for humans from 1909 • Book on scientific management by Taylor in 1911 • Moving-assembly-line techniques for car manufacturing by Ford (1913) • Project management techniques (Gantt Chart -1917) Impact of industrial revolution • Mechanization: Change of power source from muscle power and animal power to steam engine which was more economical, easier to handle and efficient than previous sources. • Social, cultural and economical change • Revolution in transport and communication • Easier and more comfortable life, better health condition • Advance in education, science, medicine, textile and agriculture • Relocation of large portions of the population from the countryside to the towns and cities • Growth in trade and business • Availability of great variety of materials • Rise of wealthy people o Especially businessman became richer, while workers also got good wages. • Start of automation replacing human operations • Negative points: break up of joint family, women and child labor, gap between poor and rich • Material growth and subsequent colonization o Demand of raw materials and nationalist pride led colonization to produce and trade goods Dutch, Portuguese (Brazil), Spanish (North and South America), French, England Negative impact of colonization ƒ Conflict and internal strife in colonized countries ƒ Extraction of vast amounts of natural resources from the colonies by British Empire

1.4 Influence of First and Second World wars on technology World War I (WWI) (1914-1918) Main Causes o Beginning: Beginning of war after the assassination of Ferdinand, heir to the AustroHungarian throne, by, a Bosnian Serb citizen of Austria-Hungary . The retaliation by Austria-Hungary against Serbia activated a series of alliances that set off a chain reaction of war declarations. Within a month, much of Europe was in a state of open warfare. Alliance of France, UK, Russia, Italy, US Alliance of Germany, Austria-Hungary o Continuing French resentment over the loss of territory to Germany in the 19th century o The growing economic and military competition between Britain and Germany o German desire to become more established countries of Europe. End of war: The war was ended by several treaties, most notably the Treaty of Versailles, signed on 28 June 1919. Technical inventions during WWI • Chemical advancement: high explosive, poison gases, fixing of atmospheric N2 • Telephone, wireless communication, armoured cars, tanks • Development of ship and aircraft, military weapons • Automatic rifle Impact of world war I on technology • Development of the mechanical equipment and scientific development of weapons accelerated

Between two wars (1918 to 1939) • •

The construction and developments were done throughout the world. Inventions of radar (1922), talking film (1922), helicopter (1924), Electronic TV (1927), Jet Engine (1937)

The Second World War (1939 to 1945) Causes a. Hitler’s Aims to dominate Europe and the World b. The aggression of Hitler’s Allies: Italy and Japan c. Democratic (USA, Britain and France) powers were passive d. The League of Nations failed to keep peace Sequences • Involved a majority of the world's nations, including all of the great powers organized into two opposing military alliances: the Allies and the Axis Axis: Germany, Japan, Italy Allies: UK, France, Poland, Russia, China, USA etc. • Starting with the German invasion of Poland in 1939 and subsequent declarations of war on Germany by the United Kingdom, France and the British Dominions • Ended with Allies victory in 1945 Inventions/ Technical developments

• • • • • • • • • •

Impact • • • • • •

Development of military weapons Jet plane, Crewless plane, Modern rockets, Helicopters Advance in tank design Advance in communication Airplanes used to carry bombs. Development of nuclear weapons Development of artificial harbors Oil pipelines under the English Channel. Acquaintance of atomic energy The modern era of automatic digital computer began during world war II o 1939 to 1944: first automatic digital computer

New technological developments in speed and arms advanced. Emergence of the Soviet Union and the United States as the superpowers. Creation of the United Nations Decolonization movement Integration of western Europe Beginning of computer age

Negative impacts of world wars ƒ Loss of life: Great human disaster ƒ Destruction of property ƒ Air, water and soil pollution ƒ Spreading of disease

1.5 Information age (1945 to present) Sequences • Post industrial era: information age • Liberation of colonized countries aftermath of war • Development of computer technology (modern computer in 1950) • Introduction of era of global satellite communication ¾ 1957: start of globalization of information revolution after Sputnik launched by Russians • Human beings in space (1961) • Communication satellite (1962) • Human being on moon (1969) • Space shuttle (1981) • Optical fiber • Laser • Exploration of space using manned/unmanned satellite • Supercomputer (1976) and Laptop computer (1989) • Robot: most vivid example in technological history • Internet: vast sources of information  

Chapter 2. The technological society 2.1 The machine age • •

Era of invention and machine-based change in society that began with the Industrial Revolution Most important development of machine age o Fossil fuels such as coal as sources of energy o Improvement of metallurgical processes (especially of steel and aluminum) o Development of electricity and electronics o Invention of the internal-combustion engine o Use of metal and cement in construction work

2.2 The steam locomotive and its impact on transportation • • •

Easier and more comfortable life Cultural diffusion and social transfusion Growth of trade and business

2.3 The telephone and telegram and their impact on telecommunication • • • • • •

Ease in conversations, conducting business, getting help in an emergency Upgrading of the social value, bridge for the social transformation Acceleration of economic growth Impact on cultural, religion and education Saving time and money for the flow of information Increased efficiency and effectiveness of the works

2.4 The automobile and its impact on mobility • • • •

Creation of job for millions and increase in the mobility of people Increment of economic activities Fast, luxurious and efficient life Noise and air pollution, causalities

2.5 Development of electronics and silicon chips •

• •

Development of computer First fully electronic computer (using vacuum tubes) in 1946 Storing program in 1946 Development of Germanium transistor in 1947 Development of modern computer with the invention of Integrated Circuit (IC) in 1950 by Jack Kilby at Texas Instruments After the invention of silicon chips, drastic change on other electronic equipments The fast development of silicon chips predicts the maturity of information era

2.6 The computer and its impact • • • • • • • • • • • •

Revolution in analysis, computation and communication, and start of information age Environmental quality control Medical diagnosis Program planning: urban planning, population studies, land use change, highway planning Increased access to the jobs Creation of new job opportunities Automation decreasing the labor intensiveness Rise of information industries Creation of high standard of living Increased production Negative impact on individuality, privacy Crime (money/information/service theft, virus, program copying, hardware/software damage etc.): threat to society

2.7 Information society •

Post industrial society in which most of the people are involved in the business of information

Transformation from industrial society to information society • After discovery of modern computer: main tool for information society ¾ Computer technology is to information age what mechanization was to the industrial revolution. ¾ In computer age, we are dealing with the conceptual space connected by electronics rather than physical space connected by motor car • Combined technology of telephone, computer and television have merged into an information and communication system • Information economy: Real, renewable and self generating economy • Revolution in communication technology due to sophisticated information technology • Application of technology to old industrial tasks and then gradually to new tasks • Focus on better education • Continuation of manufacturing industries, only change from physical to more intellectual functions • Marx theory of labor value has replaced by knowledge theory of value. • Majority of professional workers involved in information sector: e.g. teachers, lawyers, engineers, computer programmers, system analysts, architects, accountants, doctors, nurses, social workers, librarians, newspaper reporters, managers, insurance people, bankers • Information is wealth like capital in industrial society • The new source of power is not money in the hands of a few, but information in the hands of many • Scientific research expanded many folds due to information age: many journal papers, technical literatures • Robot doing skilled and unskilled job • Easy access to vast amount of information due to internet •

Challenges of information society Information age not absolute

• • • •

Erosion in employment opportunities due to computer and robot Challenge to make people computer literate Challenge to control computer related theft, fraud Challenge to implement rules and regulations for information sharing

2.8 Information as source of knowledge and power • • • • • • • •

Publication of millions of pages of scientific journals and technical literature per year Billions of websites in the internet to provide information Increase in scientific works Increased use of computer even in undeveloped countries like Nepal In an information economy, value is increased not by labor, but by knowledge Emerging communication network fueling the information society Information always worked to enhance the knowledge From the information we acquire knowledge power and therefore the source of knowledge, information, is power.

2.9 Importance of technology in the modern house • • •

Easier and comfortable life Saving time of information society Utilizing their time for their growth and development

Chapter 3. Environmental issues 3.1 Introduction Introduction to Ecology and Ecosystem Ecology • Oikos: home or surrounding, logos: study • Ecology: Science of interrelationship between organisms and their relationship with the environment Ecosystem • Natural unit which consists of biotic communities and their abiotic environment • Basic functional unit in ecology, Types: Freshwater, grassland, marine, desert Characteristics of ecosystem 1. Biotic component: producer (green plants), consumers (animals), decomposers (microorganisms) 2. Abiotic component: air, water, soil 3. Energy flow: sun main source of energy 4. Matter 5. Interrelationship 6. Biological integration 7. Flexibility 8. Ecological regulation Human impact on environment/ecosystem • Destruction or modification of habitat • Overexploitation for commercial, scientific and education purpose • Overgrazing for domestic animals • Change in arable land • Forestry • Traditional rural practice • Industrialization, Urbanization • Mining and quarrying • Pressure from introduced plants • Population pressure • Use of drugs and chemicals • Destruction of ecological balance Environmental sanitation • Cleaning of environment Environmental sanitation includes the following: 1. Collection and disposal of refuse and sewage from houses, buildings and other public places 2. Proper ventilation for the control of indoor air pollution: fresh air circulation 3. Sufficient light in the buildings for healthy conditions of human body 4. Heating Local environmental issues: water pollution, air pollution, noise pollution, solid waste pollution, deforestation, land degradation Global environmental issues: Global warming, Acid rain deposition, Ozone layer depletion

3.2 Water pollution Water pollution: presence of various types of impurities that tends to degrade its quality and either constitutes a health hazard or otherwise decrease the utility of water Sources of water pollution • Natural: Soil erosion, solutions of mineral in water, rain water, storms, earthquake, seawater intrusion, dust/dirt falling from atmosphere, deposition of animal wastes and fallen leaves etc. • Man made: Due to agriculture, sewage, wastes, industry Sewage: Liquid waste from community, contains 99.9% water, 0.1% solids (organic/inorganic matter, disease producing organisms) Types of pollutants • Pathogenic organisms • Oxygen demanding substances • Plant nutrients: Nitrogen and Phosphorus • Toxic organic chemicals: pesticides • Poisonous inorganic chemicals • Oil • Thermal pollution (Heat): from power plants • Sediment • Radioactive substances • Others: color, odor, taste Impact of water pollution • Health hazard due to the presence of pathogenic bacteria from domestic sewage, toxic materials and industrial waste Water borne diseases: typhoid, cholera, dysentery, infectious hepatitis • Economic loss: disturbance recreation, aesthetics, agriculture, industry, property • Impact on aquatic and plant life Prevention of pollution • Treatment of sewage • Treatment of industrial waste • Providing training and technical facilities in industry to treat waste water • Not using water source for discharging sewage • Rules and regulations for controlling pollution • Proper planning of towns Sewage disposal method 1. Natural methods • Dilution: discharging into water course e.g. sea, river or lake, self purification in due course of time • Land treatment: spreading sewage on land, two ways: filtration, sewage farming 2. Artificial method: Sewage treatment method for removal of suspended solids, pathogens

Cause, Effect and remedial measures of various water pollutants Physical Impurity/pollutants 1. Suspended solids (turbidity)

2. Color

Cause Clay, silt, organic matters, inorganic matter, minerals, algae, fungi Dissolved organic matters, inorganic matter and minerals, industrial waste

3. Taste and odor

Dead or living microorganisms, dissolved gases e.g. H2S, minerals, e.g. Nacl, industrial waste

Impurity/pollutants 1. Pathogenic organisms

Cause Human and animal fecal waste

Effect Turbidity, color, odor

Remedial measures Treatment: Settling, coagulation, filtration

Objectionable from aesthetic and psychological point of view, no health effect Bad smell, not suitable for drinking

Treatment method, such as aeration, treatment with activated carbon, oxidation of organic matters

Biological Effect Water-borne diseases, e.g. cholera, typhoid, paratyphoid, dysentery, diarrhea, vomiting

Remedial measures Disinfection, e.g. by boiling, by ultraviolet rays, by using ozone, potassium per magnate, chlorination

Chemical pollutants a. Some chemicals Impurity/pollutants Cause Acidity/alkalinity Presence of acid or (PH) alkali PH = log10[1/H+]

Calcium and Magnesium Chloride (In the form of NaCl) Sulfate

Fluoride

Natural Natural, pollution from sea water, brine or industrial and domestic waste Natural

Water additive for promoting strong teeth, erosion of natural deposits, fertilizer and aluminum factories

Effect Acidic water: tuberculosis, corrosion Alkaline water: incrustation, sediment deposits Hardness Not significant in small amount, salty taste, corrosion Not significant in small amount, Laxative effect, hardness, taste 1.5ppm, spotting and discoloration of teeth

Remedial measures Neutralizing

Water softening Treatment method, such as dilution, reverse osmosis, distillation Treatment method, such as reverse osmosis, distillation 1.5ppm, defluoridation (e.g. limesoda process)

Phosphate

Natural, agriculture, boiler water, laundries

b. Dissolved gas Impurity/pollutants Cause Dissolved oxygen Absorption from atmosphere Dissolved CO2 Dissolved H2S

Absorption from atmosphere Natural: due to Sulfur reducing bacteria, hot water heater fitted with Magnesium

Algal growth

Effect Positive effect: taste Negative: corrosion Bad taste, odor, corrosion Bad taste, odor, corrosion

c. Forms of Nitrogen Impurity/pollutants Cause Nitrite, Nitrate Runoff from fertilizer use, leaching from septic tanks, sewage, erosion of natural deposits Ammonia Metabolic, agriculture

d. Agrochemicals Impurity/pollutants Pesticide

Chemical fertilizer

Chemical precipitation

Remedial measures Chemical method for treatment e.g. using Sodium sulfite, boiling Treatment method, such as aeration Treatment method, such as aeration, activated carbon, oxidation

Effect Effect to infants, blue-baby syndrome, algal growth

Remedial measures Treatment method, such as biological treatment, distillation, reverse osmosis

Not of immediate health relevance, Pollution, growth of algae

Treatment method, such as biological treatment, aeration

Cause Agriculture use

Effect Positive: Increase in crop production Negative: water pollution, effect to other animals, birds, including human health

Agriculture use

Positive: Increase in crop production Negative: water pollution, algal growth

Remedial measures Pest management by ecofriendly manner, e.g. crop rotation, multi-crop agriculture, natural predator, parasites, pathogens for controlling pest, sterilization Use of organic fertilizers (manure, compost), use of minimum level of inorganic fertilizer

e. Metals Impurity/pollutants Cause Iron and Natural deposits, iron Manganese pipes

Copper

Corrosion of household

Effect Taste, color and turbidity, staining of clothes, incrustation in water mains Liver or kidney

Remedial measures Treatment method, such as aeration, oxidation Corrosion control

plumbing systems; erosion of natural deposits Zinc

Natural deposits

Aluminum

Natural deposits, treatment using Aluminium sulphate as coagulant

f. Some toxic metals Impurity/ pollutants Arsenic

Lead

Mercury

Cadmium Chromium Cyanide Barium

damage, effect on lungs, restriction in the growth of aquatic plants Not water hazard overdose: vomiting, dizziness Neurological disorders

Treatment method, such as coagulation, filtration Treatment method, such as reverse osmosis, softening

Cause

Effect

Remedial measures

Natural, Industrial effluents (glass & electronics), medicinal use

Toxic, respiratory and skin cancer, nervous disorders

Corrosion of plumbing systems, erosion of natural deposits, industrial waste, dust, paint Erosion of natural deposits, industrial discharge

Kidney problems, high blood pressure, nervous disorder

Erosion of natural deposits, industrial discharge

Cadmium: kidney, lung Chromium: respiratory Cyanide: nerve damage Barium: High blood pressure

Use of low arsenic water, e.g. rain water Treatment method, such as reverse osmosis, filtration Not using water containing lead, Treatment method, such as filtration Treatment method, such as filtration, granular activated Carbon, reverse osmosis Treatment method, such as reverse osmosis

Highly toxic, Kidney damage, nervous disorder, blurred vision

3.3 Air pollution Composition of atmosphere N2: 78%, O2: 21%, Other gases: 1% e.g. Argon, CO2, H2, He, CH4, O3, Neon, CO, NO2, NH3 etc. Air pollution: presence of certain substances in the air in high enough concentrations and for long enough duration to cause undesirable effects Sources of air pollution 1. Natural sources • Forest fires, dust storms, volcanic eruption, salt sea spray, pollen grains 2. Man made sources • Fuel combustion: coal, gas • Automobile emissions • Industrial emissions: iron and steel manufacturing, oil refining, brick factory, cement factory, chemical and petrochemical operations, pulp and paper industry, fertilizer plants, thermal power plants, textile industry etc. • Decomposition of organic waste and municipal garbage Classification of air pollutants based on origin 1. Primary: pollutants that are directly emitted to the atmosphere Main primary pollutants • SO2: due to coal burning • NO2: due to combustion of fossil fuels, e.g. coal or gasoline • CO: due to incomplete combustion of fossil fuels • Particulate matter (solid or liquid droplets, 10 µm, Smog: Smoke and fog Hazardous or toxic air pollutants • Asbestos: due to demolition of old buildings containing Asbestos fire proofing, cancer, lung disease • Benzene: due to gasoline powered vehicles, cancer • Beryllium: from foundries, ceramic factories, incinerations • Mercury: coal burning, incineration of garbage • Vinyl Chloride • Radioactive air pollutants Effects of air pollution 1. Health effects • Chronic disease, Respiratory illness: bronchitis, asthma, lung cancer • Temporary effect: nose or eye or throat irritation, coughing, chest pain, general discomfort

2. Damage to material objects • Soiling and deterioration of building surface, corrosion of metals, weakening of rubber, textile, synthetic 3. Effect on vegetation • damage to tree, flowers, fruits, vegetables 4. Effects on physical properties of atmosphere • Effects on visibility • Effects on urban atmosphere and weather conditions: fog, cloud, precipitation • Effects on atmospheric constituents: increase in atmospheric CO2 Air pollution control 1. Natural self-cleansing of the environment: dispersion by wind, settling by gravity, washout by rain, adsorption by soils, rocks, leaves, buildings 2. Control of particulate pollutants in industries using mechanical device 3. Control of gaseous pollutants in industries using mechanical device 4. Controlling air pollution from automobiles 5. Air quality legislation and standards Controlling air pollution from automobiles (CO, HC, NOx, particulates, SO2) • Catalytic convertor: for complete oxidation of combustible fuel • Reducing lead and sulfur content in gasoline • Correct operation and maintenance of engine • Fuel substitutions: use of reformulated gasoline (oxygenated fuel containing at least 2% of O2) or alternate fuels such as liquefied petroleum gas (LPG), compressed natural gas (CNG), methanol, ethanol, propane, Hydrogen, electric powered vehicle Indoor air pollution • Pollution of air inside buildings Air exchange methods: infiltration (through cracks, joints, holes), natural ventilation, forced ventilation (e.g. fans) Sources of indoor air pollution • Combustion products: tobacco smoke, combustion from stove, heater, fireplace, chimney • Asbestos: fire resistant and insulation in buildings • Radon: Radioactive decay of Radium found in soil and rock • Organic chemicals from household products: paints, waxes, varnishes, cleaning agents, pesticides, cosmetics, hobby materials • Formaldehyde: used in paints, coatings, glues, adhesives • Lead: paint, dust • Biological substances: bacteria, fungi, viruses, house dust, pollen Effects of indoor air pollution • Health problems: eye, nose and throat irritation, respiratory problem, headache, dizziness, visual problem, memory impairment, asthma, cancer, transmission of infectious disease e.g. influenza, measles etc. Remedial measures of indoor air pollution • Proper ventilation, use of fans, exhaust fans, inspection of chimneys, furnaces annually, restricted use of asbestos, proper disposal of organic materials

3.4 Noise pollution Sound: produced by mechanical vibration of sound source, transmitted in the form of wave Wavelength: distance between peaks or valleys Amplitude: height of peak of wave Frequency: no. of wavelengths in 1S (cycle/s or HZ) Single wavelength: cycle Decible scale for sound Noise pollution: unwanted sound which produce undesirable physiological and psychological effect. Source • Traffic: air traffic, road traffic and seashore and inland water traffic • Industries • Others: loudspeaker, siren, shouting, ringing bell, general daily activities Effect • • • • • • • • •

General discomfort Reduction in efficiency of persons Psychological effect Effect on sleep, recreation and personal communication Reduction in gastric activity, dizziness, rise in breathing Irritation, anxiety and stress Lack of concentration Mental fatigue Effect of prolonged exposure: Physical damage to ear, temporary/permanent hearing loss, or nervous breakdown, increase in blood pressure

Countermeasures • Protection of the recipient: use of air plugs or air muffs • Increasing path distance • Noise barriers: absorptive materials, e.g. heavy drapes, carpets, special ceiling, wall acoustic material • Reduction of noise at the source • Rules and regulations

3.5 Global warming (Greenhouse effect) Global warming • Rise in global mean temperature of the earth Solar energy: short wave radiation Energy radiated from the earth’s surface: long wave radiation Greenhouse effect • Concept of conventional greenhouse with glass: transmit short wave radiation, opaque to long wave radiation • Greenhouse effect: effect caused by greenhouse gases in the atmosphere in which short wave radiation is transmitted to the earth’s surface, but the long wave radiation from the earth is absorbed thereby increasing the temperature Greenhouse gases • Group of about 20 gases responsible for the greenhouse effect through their ability to absorb long wave terrestrial radiation • occupy less than 1% of total volume of atmosphere • Major greenhouse gases ƒ CO2: major, responsible 60% of total GHG ƒ CH4 ƒ NOx, mainly N2O: responsible 7% of total GHG ƒ Chlorofluorocarbons (CFC): responsible 25% of total GHG ƒ O3 ƒ Water vapor Cause of global warming: Enhancement of green house effect due to anthropogenic activities Sources of GHG • CO2: Burning of fossil fuels (oil, gas and coal), large scale deforestation • CH4: large scale decomposition of organic matter in swamps, rice paddy, livestock yards, cattle rising, biomass burning • N2O: soil and fertilizer, groundwater and oceans, combustion • CFC: using refrigerant, air-conditioning, fire extinguisher, cleaning solvent, blowing agent, aerosol spray • O3: upper natural environment Prediction of global warming • Using global circulation models (GCM): computer analysis of mathematical equations that model earth’s atmosphere Impact of global warming • Rise in temperature: 0.3 to 0.6 deg c in the last century • Sea level rise: due to thermal expansion of water on oceans and melting of ice caps and glaciers, 1-2 mm/year over the last century, flooding of coastal areas, beach erosion, saltwater intrusion into coastal areas • Effect on water resources: change in the pattern of evaporation and precipitation, increase in evaporation and precipitation, more precipitation on the form of rain, increase in runoff

• • •

Effect on storms and desertification: more storms, expansion of deserts and sub-arid areas with higher evaporation Socio-economic effect: chances of disease due to high temperature, increase in poverty due to flood and drought Ecological effect: effect on agriculture and forest ecosystem

Countermeasures • Environmental taxes on GHG emissions Using the revenue of tax to develop permanent and stable funding for improved efficiency and developing renewable energy sources International efforts to control global warming 1. Atmospheric scientists meeting in Geneva in 1990 • Steps to reduce emission of GHGs: industrialized nations could reduce CO2 emission by 20% by 2005 2. Earth Summit in Rio de Janeiro in 1992 • Signing of treaty to stabilize emissions of GHGs at year 1990 level by year 2000 3. Global warming conference in Berlin in 1995 • Binding time table for reduction in GHGs emission after year 2000 4. International conference in Kyoto, Japan in 1997 • Kyoto protocol: set of binding emission targets and timelines for developed nations

3.6 Acid rain PH: measure of H ion concentration, range: 0-14, 7: neutral,