The pollution problem has a direct impact on the human standard of living, so technology should not harm humans, except those who would like to use it. Therefore, environmentally friendly technology should also protect human beings by preventing pollution. Barreras et al. have made a beautiful concept in this area, “[non-environmentally friendly technologies] are responsible for the emission of a very large part of the total quantity of pollutants contained in the air, namely 40% of particles solids, 25% CO2,…” (2012). They taught that environmentally unfriendly technologies can produce many toxic gases that engineers need to be aware of. Indeed, air pollution not only affects the environment, such as global warming, but also human activity and health, such as acid rain and toxic fog. Another example given by Kempton and Letendre (1996) shows that other pollution should also be taken into account in environmentally friendly technologies in order to protect human beings. “[Environmentally unfriendly technologies] have the disadvantages of… environmental lead pollution during manufacturing and recycling” (1996). From this example, lead pollution during manufacturing and recycling becomes a drawback of an environmentally unfriendly technology. Like lead, pollution in this example can lead to the death of certain species, particularly humans. From the examples above, pollution issues put a technology at a disadvantage that engineers should avoid because it is harmful to humans. Therefore, environmentally friendly technology should be human-friendly by reducing