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Introduction to Health, Safety and Environmental Issues
8.01
Introduction to Health, Safety and Environmental Issues
MN Bassim, University of Manitoba, Winnipeg, MB, Canada Ó 2014 Elsevier Ltd. All rights reserved.
8.01.1 8.01.2 8.01.3 8.01.4 8.01.5 8.01.6 8.01.7 Further Reading
8.01.1
Historical Background – Introduction Pre-Industrial Revolution The Industrial Revolution and Manufacturing Impact of the Industrial Revolution on Health and Environment Present Impact of Manufacturing on Health and Environment Preview of the Contents of Volume 8 Conclusion
1 1 2 3 4 5 5 6
Historical Background – Introduction
The process of manufacturing involves use of machines and/or tools to mass produce products for customers or buyers. In manufacturing facilities, raw materials are fabricated and converted into goods to be sold to users. Modern manufacturing takes place in facilities known as factories. In industrialized nations, manufacturing is a large component of the national economy. Examples of manufactured products range from transportation (automobiles, trains, airplanes) to computers and electronic equipment (televisions, radios, telephones, etc.), textiles, food processing, agricultural implements, pharmaceuticals and so on. Manufacturing permeates modern life and surrounds the daily life of consumers in many ways. This modern picture was not always as it is now described throughout human civilization. Modern manufacturing was created in conjunction with the Industrial Revolution, which started in the United Kingdom (UK) in the middle of the eighteenth century to the middle of the nineteenth century. It is closely associated with the invention of the steam engine by James Watt. The Watt machine allowed conversion of energy from burning coal, found in abundance in the UK, to mechanical power through conversion of water to steam, which was then used to rotate a flywheel that provided the power to propel machines that found use in many applications. Some of the early applications included aerating mines and lifting seeping water coal to the surface, powering knitting machines for making textiles, and led to the invention of the steam locomotive, which resulted in the development of railroads for transportation of people and goods.
8.01.2
Pre-Industrial Revolution
Before the Industrial Revolution, manufacturing was mostly artisanal. Skilled craftsmen fabricated products on an individual basis for pay and sold them to customers. These craftsmen knitted fabrics, sewed clothing, tanned leather, and made shoes to size. Blacksmiths worked metals, mostly iron and copper, into kitchen utensils and potware. Some worked on making weaponry such as swords, shields, protective armor, spears, and lances. Since all these products were made individually, rarely were any multiple pieces alike. Large projects were also undertaken at the request of rulers, which necessitated the need for large groups of craftsmen to contribute. Building monuments for national purposes was one such activity. The best known constructions include the Pyramids, which were built in Egypt and are also found in Mexico; the Great Wall of China; and the Pantheon in Greece. For these monuments, stone cutters were in great demand to shape all the stones required for such huge projects. Many more skilled workers were needed to develop processes to slide and lift these stones to their final destination. During these periods of history when artisanal manufacturing was common, the scale of manufacturing was much smaller than it is today when manufacturing takes place in factories. In many cases, people engaged in artisanal manufacturing performed their tasks on a part-time basis, in conjunction with their main activity of agriculture and food production. They relied on human and animal power for the energy required to move and lift the objects and tools of their trade as well as their products. Together with the small size of the populations at this time, there was practically no concern about the impact of this small-scale manufacturing activity on the health of the workers or on the environment. The average life span in the eighteenth century was in the 30s, and it was never thought that working as a manufacturing craftsman would shorten one’s life span or influence the environment in any negative way. The implementation of the large-scale projects requested by rulers and kings, as described earlier, required gathering large numbers of workers in one place. This required planning food supplies and lodging spaces, which were mostly in small tent cities that shared many of present-day urban problems: crowding, unsanitary environment, lack of waste disposal, spreading of diseases and deaths. These conditions resulted in significant losses of populations near factories and were responsible for even more fatalities than were incurred in wars, epidemics, and natural disasters. Even as civilization and knowledge improved with time, manufacturing remained artisanal. Skilled craftsmen continued to practice and fabricate wares on an individual basis in batch-work operations, or at times, collectively by groups of artisans
Comprehensive Materials Processing, Volume 8
http://dx.doi.org/10.1016/B978-0-08-096532-1.00801-3
1
2
Introduction to Health, Safety and Environmental Issues
contributing to large projects. Gutenberg’s invention of the printing press marked a milestone in manufacturing because books could now be printed in many copies instead of being written individually by hand. This innovation had a profound impact on civilization by spreading knowledge to the population at large, leading to the development of public learning. This advance in turn ultimately led to sending children to public schools and universities and to the advancement of science and other fields of knowledge. Remarkably, the pre-Industrial Revolution era still had a significant impact on the history of the world. Long voyages of discovery by the Arabs to India, China, and other places in Asia and Africa, followed by sea explorations from Europe to Africa and then toward the New World by Columbus (1492) and other explorers around the world, required skilled craftsmen to build sturdy wooden ships for these voyages; at times these vessels were equipped with weapons such as cast-iron cannon for protection against pirates. Knowledge of metallurgy and the process of casting to produce the metallic parts of the ships (weapons, anchors, etc.) became more advanced and the roots of the science of metal processing and shaping started to take hold. During the Industrial Revolution, this knowledge led to significant progress in the science of metallurgy and materials processing, which are important parts of modern manufacturing. There was no physical correlation between artisanal manufacturing and improving the health of workers and the population at large. Life expectancy remained in the 30s and early 40s. Not only was infant mortality very high, but infectious diseases causing epidemics were common and large percentages of populations died in these epidemics. There was no running water, no sanitary sewage, and no waste disposal. People relied exclusively on candles and on tallow lamps for lighting at night. They relied on animal and human power for performance of many transportation tasks and for movement of goods and products. On rare occasions, they used natural sources of energy such as wind and waterfalls to operate mills for grinding grains. This picture changed drastically with the Industrial Revolution, which eventually led to the technological age, in which we are presently living. This was achieved by the starting and further advancement of modern manufacturing and material processing. This has come at a cost to human health and the environment. This topic is discussed in two parts: the Industrial Revolution and the Post-Industrial Revolution.
8.01.3
The Industrial Revolution and Manufacturing
Aside from Gutenberg’s invention of the printing press and the significant progress in the sciences, particularly in physics and astronomy, by Copernicus, Galileo, and others, and the discovery of the laws of gravity by Isaac Newton, the age of exploration and navigation led to the discovery of the Americas and to the voyages to Asia, including India, China, and Japan. As noted earlier, the Industrial Revolution started in the mid-eighteenth century and lasted until the mid-nineteenth century. Historians widely believe that the Industrial Revolution resulted in the initiation and further evolution of the process of manufacturing, which converts raw materials to user or consumer products by means of mechanized multiple processes using machines instead of animal or human power. The operation of these machines relies on the use of energy sources such as waterfalls or the burning of coal. As knowledge improved and electricity was discovered, coal and other energy sources were used to generate electricity, which in turn was employed to operate the machines. The Industrial Revolution started with the invention of the steam engine by James Watt. The Watt engine relied on burning coal to heat water and converting it to steam under pressure. The steam, in turn, rotated a flywheel which transmitted that motion to other machines. While the initial Watt engine had a very low power output, it created a revolution in industrial manufacturing. Among its first applications were its use in the mining industry to lift coal and water to the entrance of mines and in the burgeoning textile industry in northern England by using mechanized spinning wheels and looms to produce fabrics at much faster rates, in larger quantities, and with better quality and consistency than those produced by individual looms before the Industrial Revolution. An important consequence of the Industrial Revolution was the creation of a new field of science known as engineering, which concerned itself with applying the concepts of physics, such as Newton’s and Hooke’s laws, to the conception of mechanized machines capable of functioning at high speeds. The concept of design using the principle stated in Hooke’s law was applied in the manufacture of durable machines that could sustain performance of assigned processes. Another aspect of the Industrial Revolution was the quest for better and stronger materials to fabricate the machines and to make stronger and sturdier products either as part of other processes or for the end user. Mixing iron with carbon was known to produce a stronger alloy known as pig iron, which was used in many applications, including military weapons (cannons, gun barrels, etc.) and other products such as bases to support looms and spinning wheels. The concept of studying metallic materials, known as metallurgy, led to an understanding of the concept of alloying by adding minor amounts of other metals to either iron or copper to produce alloys such as steels (iron, carbon, and minor alloying elements such as manganese) and brasses and bronzes in copper by adding tin or zinc; copper was added to gold to give it more strength. The steelmaking process was industrialized by the invention of the Bessemer process, whereby carbon is first removed from pig iron and then controlled amounts of carbon and other alloying elements are added to control the microstructure and strength of the steel. This process allows production of an almost infinite variety of steels that can be used in many different applications. Producing steel led to the science of understanding the structure–properties relationship in metallurgy, in which steels with predetermined amounts of alloying elements, subjected to known thermomechanical treatments, would produce a steel suitable for a specific application in terms of strength, ductility, and toughness.
Introduction to Health, Safety and Environmental Issues
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The manufacturing processes were more clearly defined. Metals could be shaped by casting, forging, and machining. Welding and joining were added to that list in the early twentieth century. The lathe and the boring machines were invented for shaping and machining. Drilling holes allowed use of strong rivets to hold different parts of a piece together. Construction of metallic structures using rivets was particularly important. Later on, many of these riveted structures were replaced by welding, joining, or soldering for building bridges, ships, locomotives and rolling stock, and airplanes. Before the Industrial Revolution, the economy of nations was based on agriculture and production of food. Farmers used handmade tools made by blacksmiths who fabricated farming equipment. The mechanization of metallic materials produced stronger tools for agriculture. This resulted in more efficient means of growing food and more effective utilization of the land. Another benefit of the Industrial Revolution as it relates to agriculture was the evolution of the science of chemistry and the production of fertilizers based on ammonia and on production of dyes for coloring fabrics. The use of fertilizers resulted in improving the quality of the soil and allowed multiple crops to be grown in one-year cycles from the land. The Industrial Revolution had its strongest impact on transportation. The invention of the Watt engine resulted in a surge in this field, which started with a variation of the steam engine equipped with wheels used to run on a rail track. This is known as the locomotive. Steam locomotives based on the steam engine were still in use until about 50 years ago to pull freight cars or passenger trains to faraway destinations at a decent speed. The impact of the railroad changed the way of life in the whole world. In North America, in the United States and Canada, building cross-continent railroad lines allowed more efficient means of governing these vast countries and developing a sense of unity extending from the Atlantic to the Pacific oceans. In different parts of the world, the railroad provided new mobility for people to move about their countries, seek jobs and careers in faraway places, send their children away to study and learn, move goods and merchandise across long distances, and develop a national sense of communities among its citizens. The iron and steel industry became very important in providing products for the railroad, particularly rails, wheels, axles, and carriages. Mining for iron ore to satisfy the needs of this industry was necessary for the technological progress that the Industrial Revolution had initiated. The Industrial Revolution also impacted the development of the steamship. Before these ships were built, transportation over water depended on human power for rowing, animal power to pull small boats in rivers and canals, and wind power for the wooden ships navigating the high seas. The steamship substituted steam engines powered by coal and allowed ships to go much faster. This resulted in transoceanic ships carrying goods and people between continents. The significance of the steam engine, which led to profound societal changes, is immeasurable. It touched on many aspects of human life and ushered in the modern age. That impact extended to our way of life, to progress in health and medicine which more than doubled life expectancy. It also led to an improved quality of life. In the following sections, we examine the impact of modern manufacturing on two important aspects of modern life: health and the environment.
8.01.4
Impact of the Industrial Revolution on Health and Environment
Historians commonly believe that the Industrial Revolution drastically changed the way societies evolved in the modern (present) age. Its impact is felt in all aspects of our lives. The fact that human progress intimately depends on technology, and hence manufacturing, is overwhelming. Prior to the Industrial Revolution, societies were agrarian: People lived off the land. Cities were mostly inhabited by the ruler of the realm, his militia, and some craftsmen or artisans, who serviced the ruler and his entourage. Manufacturing was performed on a very limited scale, and it was primarily a side activity engaged in by farmers and craftsmen. At the time the Industrial Revolution began, only about 3% of the total population in England lived in cities. The Industrial Revolution created a new architectural landmark, namely, the factory, where groups of salaried people went to work every day (and night) and earned pay for their work. Factories initially focused on textile weaving, metallurgy, and steel making, dyes, and other chemical and mining and mineral processing. With time, more industries were created, including those that produced machines that were then used in the primary industries. Soon more powerful steam engines were being built, followed by looms and knitting machines, drills and lathes, and agricultural implements. Important migrations from rural areas to these factories formed the nucleus for industrial cities. The growth of these cities occurred at a very rapid pace. Cities were based on specific industries. The textile and dye and chemical industries were responsible for creating large cities in all of Europe. The migration to the cities and the expansion of the urban population created new problems, centering mostly on how to accommodate the influx from the countryside. These masses required places to live and settle, food supply lines, and other services. The merchant class was created to serve these populations. Crowded housing was hurriedly set up. With sanitation nonexistent, diseases became rampant in the cities. Tuberculosis epidemics were common in this period and were exacerbated by the pollution that resulted from burning coal needed to operate the steam engines. Other respiratory and intestinal diseases also became very common, resulting in massive death rates in urban areas. Among the most affected by these diseases were children: Child mortality rates were very high. Lack of knowledge about medicine and treatment contributed to these numbers. As a result of the alarming health conditions, the concept of doing research to discover new materials and applications as well as studying the causes of diseases was established. Universities and specialized institutes were set up to work on these new problems. In medicine, the work of Louis Pasteur on bacteria and microbes marked a major milestone of the era.
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Introduction to Health, Safety and Environmental Issues
The shifting to bulk industrialization and manufacturing had positive effects on populations. Generally, life expectancy increased, and the standard of living also improved. Life’s necessities, notably food and lodging, became more available, and the quality of life became better. Goods such as clothing also became more available. With time, sanitation improved. In the midnineteenth century, London inaugurated its first water sewage treatment plant. Clean water became available, and raw sewage was finally no longer thrown into the gutters or directly into rivers and water streams. This significantly reduced the propagation of diseases and epidemics and consequently, improved child mortality rates. At the beginning of the Industrial Revolution, the burning of coal was the main source of energy to operate stream engines, Coal was found in abundance throughout England and many countries in Europe. The burning of coal caused high pollution levels, which in turn resulted in the proliferation of diseases among urban populations who breathed the polluted air day in and day out. The burning of coal went unchecked for over 100 years, until the end of the nineteenth century when another form of energy, petroleum, considered less polluting than the direct burning of coal, became available in large quantities for the transportation industries and other applications. In those 100 years before petroleum, pollution in industrial cities was a fixture and contributed to the deaths of large numbers of urban populations. Country living, where the air was cleaner, became a symbol of good quality living and wealth. One segment of the population that was most affected by the Industrial Revolution was children and youth. Children as young as six were put to work in textile factories and in the mining industries. Child labor was widely adopted for several reasons: Notably, they were paid much less than adults for the same job, and with their smaller size they could crawl into spaces that adults could not reach, particularly in the mining and textile industries. The negative effects of child labor were both moral and practical. Children were hurt while working among moving machines and required more care from their parents. They died in large numbers in industrial accidents, sometimes because of their inexperience in dealing with dangerous situations in factories or mines. In those times, there were no laws mandating the wearing of helmets or protective shoes. Children were mostly barefoot while working, and accidents occurred on a daily basis. With time and despite strong resistance from employers, child labor laws were passed that controlled and prohibited children below a certain age from working. Public school systems that included compulsory attendance up to a certain age, or education level, were also implemented. School buildings for child education became part of the landscape in cities and villages alike, and the problem of child labor in industrial countries finally came to an end. The impact of modern manufacturing on the environment has been strong from its inception. For more than a hundred years after it started in Europe and in North America, modern manufacturing negatively affected the environment. The damage to the environment was not considered a priority, however, and so was ignored. Industrial pollution was allowed to continue, contaminating the air around the globe: initially by burning coal and sending large amount of carbon dioxide (CO2) into the atmosphere, and by polluting rivers and streams with toxic wastes that destroyed the quality of the water and killed fish and aquatic animals and plants. In the initial stages of the Industrial Revolution, raw sewage was routinely dumped into rivers and streams, causing the propagation of diseases and epidemics that wiped out large numbers of people. It is only due to the capacity of our planet to absorb the pollution resulting from manufacturing that no more serious environmental calamities have occurred. Natural sites such as green areas, Arctic and Antarctic regions, rain forests, and the ozone layer have helped renew the air we breathe and the water we drink. These protective sites have long acted as shields for planet Earth, allowing the continuation of life for humans and flora and fauna alike.
8.01.5
Present Impact of Manufacturing on Health and Environment
At the beginning of the twenty-first century, manufacturing has established itself as the cornerstone of the economy of the world’s industrialized countries. These countries, members of the organization for Economic Co-operation and Development (OECD), are market economies based largely on manufacturing, which is defined as the means of using machines or assembly set up to produce goods for use or sale. These goods or products may be used directly by a user or consumer, or they may serve as a means of production sold to other manufacturers for producing consumer goods sold to end users. Manufacturing and technology permeate all aspects of our lives from consumer products made with metals and alloys such as housewares, to fabrics for clothing, to means of transportation that include automobiles, trains, boats, and airplanes, to communication equipment such as radios, televisions, telephones, and more recently, computers and digital equipment. New materials besides metals have been discovered. They include polymers/plastics, composites, semiconductors, advanced ceramics and, more recently, nanomaterials. Significant advances have been made in biology and medicine. We now understand the way the body functions. Life expectancy in most countries in the planet has doubled since the start of the Industrial Revolution, infant mortality has decreased significantly, and many diseases have been eradicated. Clean drinking water is available to many more people. The discovery of penicillin and other antibiotics has diminished the risk of sickness or death from influenza, which as late as the 1920s used to spread in epidemics killing thousands of people. We are close to beating cancer in our lifetime, and medical researchers are working on curing diabetes, stroke, and heart disease, among other diseases. As stated earlier, the impact of manufacturing on the environment was not considered important for more than a century after modern manufacturing began. It was simply not seen as a factor in regulating manufacturing because it was assumed that the planet could absorb and rid itself of the toxic effects of manufacturing. As manufacturing expanded across the globe, particularly in Asia, it became more urgent to consider its effect on health and environment. Pollution in the atmosphere by production of CO2, acid rain,
Introduction to Health, Safety and Environmental Issues
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holes in the ozone layer, pollution of many rivers and streams, burning of coal, proliferation of automobiles and airplanes – all contributed to an awareness of the impact of modern technology on the environment and to question whether this pollution would affect our life cycle. More recently, noticeable changes in the earth’s climate causing global warming have evoked serious questions about environmental effects. The countries most involved in manufacturing and those joining with this group have started to take a regulatory approach in approving new technologies and manufacturing facilities. The creation of the Environmental Protection Agency in the United States is an example of such efforts. Similar agencies have been set up in OECD countries. They mandate environmental impact studies, which are essential and compulsory for approval of any project that may present risks to the environment. They also conduct research to examine the degree of toxicity to the environment and to living organisms, including human. These organizations have enacted regulatory laws dealing with specific aspects of manufacturing, such as materials processing, including casting, machining, forging, and welding. Products that may impact the environment over long periods of time, such as metal and plastics/polymers, are being studied in order to come up with alternatives such as biodegradable materials (natural organic materials such as wood and paper). The concept of recycling and reusing manufactured products has gained a high profile as a means of decreasing the level of pollution produced by metals and polymers. Use of lighter and stronger materials such as composites in automobiles and airplanes may reduce CO2 emissions. While manufacturing continues to be the backbone of the industrial economies, significant efforts across the globe are taking place to make manufacturing compliant to preserving the quality of the environment. The risk of ruining the environment beyond repair has become a wake-up call for nations to reduce all forms of pollution and to take decisions to ensure that manufacturing does not destroy the environment. Manufacturing has had a less drastic effect on health than on the environment. Although in the early days of the Industrial Revolution, epidemics ravaged populations with tuberculosis and other pulmonary diseases and child mortality was very high, great strides have been made in health care: Many medical discoveries have prolonged life expectancy and reduced child mortality. This being said, in some instances, manufacturing may have contributed to sickness and death. An example is the use of asbestos as an insulating material, which contributed to pulmonary diseases and death among asbestos workers. Regulatory laws and directives have been imposed over the years to prevent diseases among workers in these industries. With time, a healthier work climate has prevailed, and the impact of manufacturing on health has decreased. Wearing safety helmets and safety boots in factories is mandatory in most countries. Also, safety glasses are required to protect the eyes. Other regulations deal with specific conditions in industrial environments, such as wearing of protective masks for welders.
8.01.6
Preview of the Contents of Volume 8
Volume 8 deals with the effect of materials processing during manufacturing on health and the environment. It examines conventional materials such as steels and other metals and alloys as they are shaped to make products. Such processes may deal with various aspects of casting to produce parts by cooling a liquid metal from melt. Hazards with casting may come from handling hot liquid metal, from processing molds: making the mold, breaking the mold, and shaping fine particles of sand to produce the mold. In powder metallurgy, parts are molded under pressure from powder and then subjected to very high temperatures that cause sintering and vitrification. Inhaling fine metallic or ceramic particles is a health hazard, as is working with autoclaves at high temperatures. Machining and forging also present health hazards to workers using lathes, milling machines, and boring machines. There is risk of injury from metal shavings and of clothes caught in the gears of the machines. Welding of metals and alloys requires developing experience in dealing with high-temperature environments, working with toxic flux materials, and inhaling toxic vapors. Nonmetallic materials such as ceramics, polymers, and composites also represent health hazards in working with toxic materials and in inhaling small particles of ceramics. New materials such as nanocomposites represent new challenges in determining the potential risks to health and to pollution from ultra-fine particles. Finally, the economic impact of manufacturing and the balance between producing goods for the end user and profit for the company has to be balanced by concern for damaging the environment and creating health hazards for workers and consumers.
8.01.7
Conclusion
This chapter presents a historical perspective on the evolution of modern manufacturing processes as a manifestation of the Industrial Revolution. The Industrial Revolution started with the invention of the steam engine. This invention drastically changed the production of goods, allowing production on a much larger scale than was possible by artisans and craftsmen. Manufacturing started in the areas of textiles, dyes and chemicals, iron and steel, and mining. It caused a radical shift from rural agrarian societies to urban societies, with workers receiving salaries for operating machines. Burning coal for the steam engine produced significant pollution. Crowding in the cities raised the risk of contagious diseases and the propagation of epidemics, especially tuberculosis. Child labor was initially widespread and was halted only when laws prohibiting it were enacted. Structuring public education was
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Introduction to Health, Safety and Environmental Issues
a consequence of these laws, now sending children to school instead of work. Transportation using steam engines as locomotives created railroads and facilitated the movement of people and goods. Manufacturing technologies are the economic engines of industrialized nations. From the Industrial Revolution in the eighteenth century until the mid-twentieth century, concern over the impact of manufacturing on the environment was minimal. As signs of deterioration of the environment became ominous – notably, polluted rivers, CO2 in air, acid rain, holes in the ozone layer, regulatory steps were undertaken to prevent further damage. Environmental assessment of new large products became compulsory, and research on environmental and health impacts led to legal regulation. Recycling of metallic, paper, and polymer materials to protect the environment was encouraged and became prevalent. Health standards were enforced to prevent the spread of diseases. Medical discoveries were made to find cures for diseases related to manufacturing and pollution such as various forms of cancer and respiratory diseases.
Further Reading 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Maddison, A. The World Economy: Historical Statistics; Paris Development Centre OECD, 2003. Berg, M.; Hudson, P. Rehabilitating the Industrial Revolution. Econ. Hist. Rev. 1992, 45. Lucas, R. E. Lectures on Economic Growth; Harvard University Press, 2002. de Crouzet, F. The Industrial Revolution in National Context: Europe and the USA; Cambridge University Press, 1996. McCloskey, D. Review of the Cambridge History of Modern Britain; Times Higher Education Supplement, 2004. Hartwell, R. M. The Industrial Revolution and Economic Growth; Methuen and Co, 1971. Buer, M. C. Wealth and Population in the Early Days of the Industrial Revolution; George Routledge & Sons, 1926. Manufacturing and Investment around the World: An International Survey of Factors Affecting Growth & Performance, revised 2nd ed.; ISR Publications, Google Books, 2002. Research in Industrial Systems, revised 2nd ed.; ISR Publications, Google Books, 2002. Kalpakjuan, S.; Schmid, S. Manufacturing, Engineering & Technology; Prentice Hall, 2005. Black, J. T.; Kohser, R. A. De Garmo’s Materials & Processes in Manufacturing, 10th ed.; John Wiley & Sons, 2007.
Introduction to Health, Safety and Environmental Issues
MN Bassim, University of Manitoba, Winnipeg, MB, Canada Ó 2014 Elsevier Ltd. All rights reserved.
8.01.1 8.01.2 8.01.3 8.01.4 8.01.5 8.01.6 8.01.7 Further Reading
8.01.1
Historical Background – Introduction Pre-Industrial Revolution The Industrial Revolution and Manufacturing Impact of the Industrial Revolution on Health and Environment Present Impact of Manufacturing on Health and Environment Preview of the Contents of Volume 8 Conclusion
1 1 2 3 4 5 5 6
Historical Background – Introduction
The process of manufacturing involves use of machines and/or tools to mass produce products for customers or buyers. In manufacturing facilities, raw materials are fabricated and converted into goods to be sold to users. Modern manufacturing takes place in facilities known as factories. In industrialized nations, manufacturing is a large component of the national economy. Examples of manufactured products range from transportation (automobiles, trains, airplanes) to computers and electronic equipment (televisions, radios, telephones, etc.), textiles, food processing, agricultural implements, pharmaceuticals and so on. Manufacturing permeates modern life and surrounds the daily life of consumers in many ways. This modern picture was not always as it is now described throughout human civilization. Modern manufacturing was created in conjunction with the Industrial Revolution, which started in the United Kingdom (UK) in the middle of the eighteenth century to the middle of the nineteenth century. It is closely associated with the invention of the steam engine by James Watt. The Watt machine allowed conversion of energy from burning coal, found in abundance in the UK, to mechanical power through conversion of water to steam, which was then used to rotate a flywheel that provided the power to propel machines that found use in many applications. Some of the early applications included aerating mines and lifting seeping water coal to the surface, powering knitting machines for making textiles, and led to the invention of the steam locomotive, which resulted in the development of railroads for transportation of people and goods.
8.01.2
Pre-Industrial Revolution
Before the Industrial Revolution, manufacturing was mostly artisanal. Skilled craftsmen fabricated products on an individual basis for pay and sold them to customers. These craftsmen knitted fabrics, sewed clothing, tanned leather, and made shoes to size. Blacksmiths worked metals, mostly iron and copper, into kitchen utensils and potware. Some worked on making weaponry such as swords, shields, protective armor, spears, and lances. Since all these products were made individually, rarely were any multiple pieces alike. Large projects were also undertaken at the request of rulers, which necessitated the need for large groups of craftsmen to contribute. Building monuments for national purposes was one such activity. The best known constructions include the Pyramids, which were built in Egypt and are also found in Mexico; the Great Wall of China; and the Pantheon in Greece. For these monuments, stone cutters were in great demand to shape all the stones required for such huge projects. Many more skilled workers were needed to develop processes to slide and lift these stones to their final destination. During these periods of history when artisanal manufacturing was common, the scale of manufacturing was much smaller than it is today when manufacturing takes place in factories. In many cases, people engaged in artisanal manufacturing performed their tasks on a part-time basis, in conjunction with their main activity of agriculture and food production. They relied on human and animal power for the energy required to move and lift the objects and tools of their trade as well as their products. Together with the small size of the populations at this time, there was practically no concern about the impact of this small-scale manufacturing activity on the health of the workers or on the environment. The average life span in the eighteenth century was in the 30s, and it was never thought that working as a manufacturing craftsman would shorten one’s life span or influence the environment in any negative way. The implementation of the large-scale projects requested by rulers and kings, as described earlier, required gathering large numbers of workers in one place. This required planning food supplies and lodging spaces, which were mostly in small tent cities that shared many of present-day urban problems: crowding, unsanitary environment, lack of waste disposal, spreading of diseases and deaths. These conditions resulted in significant losses of populations near factories and were responsible for even more fatalities than were incurred in wars, epidemics, and natural disasters. Even as civilization and knowledge improved with time, manufacturing remained artisanal. Skilled craftsmen continued to practice and fabricate wares on an individual basis in batch-work operations, or at times, collectively by groups of artisans
Comprehensive Materials Processing, Volume 8
http://dx.doi.org/10.1016/B978-0-08-096532-1.00801-3
1
2
Introduction to Health, Safety and Environmental Issues
contributing to large projects. Gutenberg’s invention of the printing press marked a milestone in manufacturing because books could now be printed in many copies instead of being written individually by hand. This innovation had a profound impact on civilization by spreading knowledge to the population at large, leading to the development of public learning. This advance in turn ultimately led to sending children to public schools and universities and to the advancement of science and other fields of knowledge. Remarkably, the pre-Industrial Revolution era still had a significant impact on the history of the world. Long voyages of discovery by the Arabs to India, China, and other places in Asia and Africa, followed by sea explorations from Europe to Africa and then toward the New World by Columbus (1492) and other explorers around the world, required skilled craftsmen to build sturdy wooden ships for these voyages; at times these vessels were equipped with weapons such as cast-iron cannon for protection against pirates. Knowledge of metallurgy and the process of casting to produce the metallic parts of the ships (weapons, anchors, etc.) became more advanced and the roots of the science of metal processing and shaping started to take hold. During the Industrial Revolution, this knowledge led to significant progress in the science of metallurgy and materials processing, which are important parts of modern manufacturing. There was no physical correlation between artisanal manufacturing and improving the health of workers and the population at large. Life expectancy remained in the 30s and early 40s. Not only was infant mortality very high, but infectious diseases causing epidemics were common and large percentages of populations died in these epidemics. There was no running water, no sanitary sewage, and no waste disposal. People relied exclusively on candles and on tallow lamps for lighting at night. They relied on animal and human power for performance of many transportation tasks and for movement of goods and products. On rare occasions, they used natural sources of energy such as wind and waterfalls to operate mills for grinding grains. This picture changed drastically with the Industrial Revolution, which eventually led to the technological age, in which we are presently living. This was achieved by the starting and further advancement of modern manufacturing and material processing. This has come at a cost to human health and the environment. This topic is discussed in two parts: the Industrial Revolution and the Post-Industrial Revolution.
8.01.3
The Industrial Revolution and Manufacturing
Aside from Gutenberg’s invention of the printing press and the significant progress in the sciences, particularly in physics and astronomy, by Copernicus, Galileo, and others, and the discovery of the laws of gravity by Isaac Newton, the age of exploration and navigation led to the discovery of the Americas and to the voyages to Asia, including India, China, and Japan. As noted earlier, the Industrial Revolution started in the mid-eighteenth century and lasted until the mid-nineteenth century. Historians widely believe that the Industrial Revolution resulted in the initiation and further evolution of the process of manufacturing, which converts raw materials to user or consumer products by means of mechanized multiple processes using machines instead of animal or human power. The operation of these machines relies on the use of energy sources such as waterfalls or the burning of coal. As knowledge improved and electricity was discovered, coal and other energy sources were used to generate electricity, which in turn was employed to operate the machines. The Industrial Revolution started with the invention of the steam engine by James Watt. The Watt engine relied on burning coal to heat water and converting it to steam under pressure. The steam, in turn, rotated a flywheel which transmitted that motion to other machines. While the initial Watt engine had a very low power output, it created a revolution in industrial manufacturing. Among its first applications were its use in the mining industry to lift coal and water to the entrance of mines and in the burgeoning textile industry in northern England by using mechanized spinning wheels and looms to produce fabrics at much faster rates, in larger quantities, and with better quality and consistency than those produced by individual looms before the Industrial Revolution. An important consequence of the Industrial Revolution was the creation of a new field of science known as engineering, which concerned itself with applying the concepts of physics, such as Newton’s and Hooke’s laws, to the conception of mechanized machines capable of functioning at high speeds. The concept of design using the principle stated in Hooke’s law was applied in the manufacture of durable machines that could sustain performance of assigned processes. Another aspect of the Industrial Revolution was the quest for better and stronger materials to fabricate the machines and to make stronger and sturdier products either as part of other processes or for the end user. Mixing iron with carbon was known to produce a stronger alloy known as pig iron, which was used in many applications, including military weapons (cannons, gun barrels, etc.) and other products such as bases to support looms and spinning wheels. The concept of studying metallic materials, known as metallurgy, led to an understanding of the concept of alloying by adding minor amounts of other metals to either iron or copper to produce alloys such as steels (iron, carbon, and minor alloying elements such as manganese) and brasses and bronzes in copper by adding tin or zinc; copper was added to gold to give it more strength. The steelmaking process was industrialized by the invention of the Bessemer process, whereby carbon is first removed from pig iron and then controlled amounts of carbon and other alloying elements are added to control the microstructure and strength of the steel. This process allows production of an almost infinite variety of steels that can be used in many different applications. Producing steel led to the science of understanding the structure–properties relationship in metallurgy, in which steels with predetermined amounts of alloying elements, subjected to known thermomechanical treatments, would produce a steel suitable for a specific application in terms of strength, ductility, and toughness.
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The manufacturing processes were more clearly defined. Metals could be shaped by casting, forging, and machining. Welding and joining were added to that list in the early twentieth century. The lathe and the boring machines were invented for shaping and machining. Drilling holes allowed use of strong rivets to hold different parts of a piece together. Construction of metallic structures using rivets was particularly important. Later on, many of these riveted structures were replaced by welding, joining, or soldering for building bridges, ships, locomotives and rolling stock, and airplanes. Before the Industrial Revolution, the economy of nations was based on agriculture and production of food. Farmers used handmade tools made by blacksmiths who fabricated farming equipment. The mechanization of metallic materials produced stronger tools for agriculture. This resulted in more efficient means of growing food and more effective utilization of the land. Another benefit of the Industrial Revolution as it relates to agriculture was the evolution of the science of chemistry and the production of fertilizers based on ammonia and on production of dyes for coloring fabrics. The use of fertilizers resulted in improving the quality of the soil and allowed multiple crops to be grown in one-year cycles from the land. The Industrial Revolution had its strongest impact on transportation. The invention of the Watt engine resulted in a surge in this field, which started with a variation of the steam engine equipped with wheels used to run on a rail track. This is known as the locomotive. Steam locomotives based on the steam engine were still in use until about 50 years ago to pull freight cars or passenger trains to faraway destinations at a decent speed. The impact of the railroad changed the way of life in the whole world. In North America, in the United States and Canada, building cross-continent railroad lines allowed more efficient means of governing these vast countries and developing a sense of unity extending from the Atlantic to the Pacific oceans. In different parts of the world, the railroad provided new mobility for people to move about their countries, seek jobs and careers in faraway places, send their children away to study and learn, move goods and merchandise across long distances, and develop a national sense of communities among its citizens. The iron and steel industry became very important in providing products for the railroad, particularly rails, wheels, axles, and carriages. Mining for iron ore to satisfy the needs of this industry was necessary for the technological progress that the Industrial Revolution had initiated. The Industrial Revolution also impacted the development of the steamship. Before these ships were built, transportation over water depended on human power for rowing, animal power to pull small boats in rivers and canals, and wind power for the wooden ships navigating the high seas. The steamship substituted steam engines powered by coal and allowed ships to go much faster. This resulted in transoceanic ships carrying goods and people between continents. The significance of the steam engine, which led to profound societal changes, is immeasurable. It touched on many aspects of human life and ushered in the modern age. That impact extended to our way of life, to progress in health and medicine which more than doubled life expectancy. It also led to an improved quality of life. In the following sections, we examine the impact of modern manufacturing on two important aspects of modern life: health and the environment.
8.01.4
Impact of the Industrial Revolution on Health and Environment
Historians commonly believe that the Industrial Revolution drastically changed the way societies evolved in the modern (present) age. Its impact is felt in all aspects of our lives. The fact that human progress intimately depends on technology, and hence manufacturing, is overwhelming. Prior to the Industrial Revolution, societies were agrarian: People lived off the land. Cities were mostly inhabited by the ruler of the realm, his militia, and some craftsmen or artisans, who serviced the ruler and his entourage. Manufacturing was performed on a very limited scale, and it was primarily a side activity engaged in by farmers and craftsmen. At the time the Industrial Revolution began, only about 3% of the total population in England lived in cities. The Industrial Revolution created a new architectural landmark, namely, the factory, where groups of salaried people went to work every day (and night) and earned pay for their work. Factories initially focused on textile weaving, metallurgy, and steel making, dyes, and other chemical and mining and mineral processing. With time, more industries were created, including those that produced machines that were then used in the primary industries. Soon more powerful steam engines were being built, followed by looms and knitting machines, drills and lathes, and agricultural implements. Important migrations from rural areas to these factories formed the nucleus for industrial cities. The growth of these cities occurred at a very rapid pace. Cities were based on specific industries. The textile and dye and chemical industries were responsible for creating large cities in all of Europe. The migration to the cities and the expansion of the urban population created new problems, centering mostly on how to accommodate the influx from the countryside. These masses required places to live and settle, food supply lines, and other services. The merchant class was created to serve these populations. Crowded housing was hurriedly set up. With sanitation nonexistent, diseases became rampant in the cities. Tuberculosis epidemics were common in this period and were exacerbated by the pollution that resulted from burning coal needed to operate the steam engines. Other respiratory and intestinal diseases also became very common, resulting in massive death rates in urban areas. Among the most affected by these diseases were children: Child mortality rates were very high. Lack of knowledge about medicine and treatment contributed to these numbers. As a result of the alarming health conditions, the concept of doing research to discover new materials and applications as well as studying the causes of diseases was established. Universities and specialized institutes were set up to work on these new problems. In medicine, the work of Louis Pasteur on bacteria and microbes marked a major milestone of the era.
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The shifting to bulk industrialization and manufacturing had positive effects on populations. Generally, life expectancy increased, and the standard of living also improved. Life’s necessities, notably food and lodging, became more available, and the quality of life became better. Goods such as clothing also became more available. With time, sanitation improved. In the midnineteenth century, London inaugurated its first water sewage treatment plant. Clean water became available, and raw sewage was finally no longer thrown into the gutters or directly into rivers and water streams. This significantly reduced the propagation of diseases and epidemics and consequently, improved child mortality rates. At the beginning of the Industrial Revolution, the burning of coal was the main source of energy to operate stream engines, Coal was found in abundance throughout England and many countries in Europe. The burning of coal caused high pollution levels, which in turn resulted in the proliferation of diseases among urban populations who breathed the polluted air day in and day out. The burning of coal went unchecked for over 100 years, until the end of the nineteenth century when another form of energy, petroleum, considered less polluting than the direct burning of coal, became available in large quantities for the transportation industries and other applications. In those 100 years before petroleum, pollution in industrial cities was a fixture and contributed to the deaths of large numbers of urban populations. Country living, where the air was cleaner, became a symbol of good quality living and wealth. One segment of the population that was most affected by the Industrial Revolution was children and youth. Children as young as six were put to work in textile factories and in the mining industries. Child labor was widely adopted for several reasons: Notably, they were paid much less than adults for the same job, and with their smaller size they could crawl into spaces that adults could not reach, particularly in the mining and textile industries. The negative effects of child labor were both moral and practical. Children were hurt while working among moving machines and required more care from their parents. They died in large numbers in industrial accidents, sometimes because of their inexperience in dealing with dangerous situations in factories or mines. In those times, there were no laws mandating the wearing of helmets or protective shoes. Children were mostly barefoot while working, and accidents occurred on a daily basis. With time and despite strong resistance from employers, child labor laws were passed that controlled and prohibited children below a certain age from working. Public school systems that included compulsory attendance up to a certain age, or education level, were also implemented. School buildings for child education became part of the landscape in cities and villages alike, and the problem of child labor in industrial countries finally came to an end. The impact of modern manufacturing on the environment has been strong from its inception. For more than a hundred years after it started in Europe and in North America, modern manufacturing negatively affected the environment. The damage to the environment was not considered a priority, however, and so was ignored. Industrial pollution was allowed to continue, contaminating the air around the globe: initially by burning coal and sending large amount of carbon dioxide (CO2) into the atmosphere, and by polluting rivers and streams with toxic wastes that destroyed the quality of the water and killed fish and aquatic animals and plants. In the initial stages of the Industrial Revolution, raw sewage was routinely dumped into rivers and streams, causing the propagation of diseases and epidemics that wiped out large numbers of people. It is only due to the capacity of our planet to absorb the pollution resulting from manufacturing that no more serious environmental calamities have occurred. Natural sites such as green areas, Arctic and Antarctic regions, rain forests, and the ozone layer have helped renew the air we breathe and the water we drink. These protective sites have long acted as shields for planet Earth, allowing the continuation of life for humans and flora and fauna alike.
8.01.5
Present Impact of Manufacturing on Health and Environment
At the beginning of the twenty-first century, manufacturing has established itself as the cornerstone of the economy of the world’s industrialized countries. These countries, members of the organization for Economic Co-operation and Development (OECD), are market economies based largely on manufacturing, which is defined as the means of using machines or assembly set up to produce goods for use or sale. These goods or products may be used directly by a user or consumer, or they may serve as a means of production sold to other manufacturers for producing consumer goods sold to end users. Manufacturing and technology permeate all aspects of our lives from consumer products made with metals and alloys such as housewares, to fabrics for clothing, to means of transportation that include automobiles, trains, boats, and airplanes, to communication equipment such as radios, televisions, telephones, and more recently, computers and digital equipment. New materials besides metals have been discovered. They include polymers/plastics, composites, semiconductors, advanced ceramics and, more recently, nanomaterials. Significant advances have been made in biology and medicine. We now understand the way the body functions. Life expectancy in most countries in the planet has doubled since the start of the Industrial Revolution, infant mortality has decreased significantly, and many diseases have been eradicated. Clean drinking water is available to many more people. The discovery of penicillin and other antibiotics has diminished the risk of sickness or death from influenza, which as late as the 1920s used to spread in epidemics killing thousands of people. We are close to beating cancer in our lifetime, and medical researchers are working on curing diabetes, stroke, and heart disease, among other diseases. As stated earlier, the impact of manufacturing on the environment was not considered important for more than a century after modern manufacturing began. It was simply not seen as a factor in regulating manufacturing because it was assumed that the planet could absorb and rid itself of the toxic effects of manufacturing. As manufacturing expanded across the globe, particularly in Asia, it became more urgent to consider its effect on health and environment. Pollution in the atmosphere by production of CO2, acid rain,
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holes in the ozone layer, pollution of many rivers and streams, burning of coal, proliferation of automobiles and airplanes – all contributed to an awareness of the impact of modern technology on the environment and to question whether this pollution would affect our life cycle. More recently, noticeable changes in the earth’s climate causing global warming have evoked serious questions about environmental effects. The countries most involved in manufacturing and those joining with this group have started to take a regulatory approach in approving new technologies and manufacturing facilities. The creation of the Environmental Protection Agency in the United States is an example of such efforts. Similar agencies have been set up in OECD countries. They mandate environmental impact studies, which are essential and compulsory for approval of any project that may present risks to the environment. They also conduct research to examine the degree of toxicity to the environment and to living organisms, including human. These organizations have enacted regulatory laws dealing with specific aspects of manufacturing, such as materials processing, including casting, machining, forging, and welding. Products that may impact the environment over long periods of time, such as metal and plastics/polymers, are being studied in order to come up with alternatives such as biodegradable materials (natural organic materials such as wood and paper). The concept of recycling and reusing manufactured products has gained a high profile as a means of decreasing the level of pollution produced by metals and polymers. Use of lighter and stronger materials such as composites in automobiles and airplanes may reduce CO2 emissions. While manufacturing continues to be the backbone of the industrial economies, significant efforts across the globe are taking place to make manufacturing compliant to preserving the quality of the environment. The risk of ruining the environment beyond repair has become a wake-up call for nations to reduce all forms of pollution and to take decisions to ensure that manufacturing does not destroy the environment. Manufacturing has had a less drastic effect on health than on the environment. Although in the early days of the Industrial Revolution, epidemics ravaged populations with tuberculosis and other pulmonary diseases and child mortality was very high, great strides have been made in health care: Many medical discoveries have prolonged life expectancy and reduced child mortality. This being said, in some instances, manufacturing may have contributed to sickness and death. An example is the use of asbestos as an insulating material, which contributed to pulmonary diseases and death among asbestos workers. Regulatory laws and directives have been imposed over the years to prevent diseases among workers in these industries. With time, a healthier work climate has prevailed, and the impact of manufacturing on health has decreased. Wearing safety helmets and safety boots in factories is mandatory in most countries. Also, safety glasses are required to protect the eyes. Other regulations deal with specific conditions in industrial environments, such as wearing of protective masks for welders.
8.01.6
Preview of the Contents of Volume 8
Volume 8 deals with the effect of materials processing during manufacturing on health and the environment. It examines conventional materials such as steels and other metals and alloys as they are shaped to make products. Such processes may deal with various aspects of casting to produce parts by cooling a liquid metal from melt. Hazards with casting may come from handling hot liquid metal, from processing molds: making the mold, breaking the mold, and shaping fine particles of sand to produce the mold. In powder metallurgy, parts are molded under pressure from powder and then subjected to very high temperatures that cause sintering and vitrification. Inhaling fine metallic or ceramic particles is a health hazard, as is working with autoclaves at high temperatures. Machining and forging also present health hazards to workers using lathes, milling machines, and boring machines. There is risk of injury from metal shavings and of clothes caught in the gears of the machines. Welding of metals and alloys requires developing experience in dealing with high-temperature environments, working with toxic flux materials, and inhaling toxic vapors. Nonmetallic materials such as ceramics, polymers, and composites also represent health hazards in working with toxic materials and in inhaling small particles of ceramics. New materials such as nanocomposites represent new challenges in determining the potential risks to health and to pollution from ultra-fine particles. Finally, the economic impact of manufacturing and the balance between producing goods for the end user and profit for the company has to be balanced by concern for damaging the environment and creating health hazards for workers and consumers.
8.01.7
Conclusion
This chapter presents a historical perspective on the evolution of modern manufacturing processes as a manifestation of the Industrial Revolution. The Industrial Revolution started with the invention of the steam engine. This invention drastically changed the production of goods, allowing production on a much larger scale than was possible by artisans and craftsmen. Manufacturing started in the areas of textiles, dyes and chemicals, iron and steel, and mining. It caused a radical shift from rural agrarian societies to urban societies, with workers receiving salaries for operating machines. Burning coal for the steam engine produced significant pollution. Crowding in the cities raised the risk of contagious diseases and the propagation of epidemics, especially tuberculosis. Child labor was initially widespread and was halted only when laws prohibiting it were enacted. Structuring public education was
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a consequence of these laws, now sending children to school instead of work. Transportation using steam engines as locomotives created railroads and facilitated the movement of people and goods. Manufacturing technologies are the economic engines of industrialized nations. From the Industrial Revolution in the eighteenth century until the mid-twentieth century, concern over the impact of manufacturing on the environment was minimal. As signs of deterioration of the environment became ominous – notably, polluted rivers, CO2 in air, acid rain, holes in the ozone layer, regulatory steps were undertaken to prevent further damage. Environmental assessment of new large products became compulsory, and research on environmental and health impacts led to legal regulation. Recycling of metallic, paper, and polymer materials to protect the environment was encouraged and became prevalent. Health standards were enforced to prevent the spread of diseases. Medical discoveries were made to find cures for diseases related to manufacturing and pollution such as various forms of cancer and respiratory diseases.
Further Reading 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Maddison, A. The World Economy: Historical Statistics; Paris Development Centre OECD, 2003. Berg, M.; Hudson, P. Rehabilitating the Industrial Revolution. Econ. Hist. Rev. 1992, 45. Lucas, R. E. Lectures on Economic Growth; Harvard University Press, 2002. de Crouzet, F. The Industrial Revolution in National Context: Europe and the USA; Cambridge University Press, 1996. McCloskey, D. Review of the Cambridge History of Modern Britain; Times Higher Education Supplement, 2004. Hartwell, R. M. The Industrial Revolution and Economic Growth; Methuen and Co, 1971. Buer, M. C. Wealth and Population in the Early Days of the Industrial Revolution; George Routledge & Sons, 1926. Manufacturing and Investment around the World: An International Survey of Factors Affecting Growth & Performance, revised 2nd ed.; ISR Publications, Google Books, 2002. Research in Industrial Systems, revised 2nd ed.; ISR Publications, Google Books, 2002. Kalpakjuan, S.; Schmid, S. Manufacturing, Engineering & Technology; Prentice Hall, 2005. Black, J. T.; Kohser, R. A. De Garmo’s Materials & Processes in Manufacturing, 10th ed.; John Wiley & Sons, 2007.