ECOLOGY AND THE CONSERVATION OF NATURAL RESOURCES
|Energy Resources and Demands
|Science in Society
To develop an understanding of the interdependence of all organisms and the need for conserving natural resources
An adequate and continuous supply of soil, water, air, and energy are essential to the survival of living things.
Ecology O4.00 To understand methods of maintaining air quality
INSTRUCTIONAL OBJECTIVE: The learner will:
OUTLINE OF CONTENT:
I. Measures to protect indoor air quality
A. Allow for reasonable amount of ventilation
II. Measures to protect outdoor air quality
B. Do not allow smoking indoors
C. Insulate only with high grade material
D. Use wood stove properly
E. Use indoor air purifier
A. Require local governments to insure proper release techniques from industry
III. Improvement of air quality
B. Control automobile emissions
1. Support legislation that would require auto makers to comply with emission standards
2. Support use of alcohol as a fuel
3. Support phasing out internal combustion engine
4. Encourage car pools
5. Establish bus lanes and expand mass transit
A. Carbon monoxide
B. Oxides of nitrogen
E. Particle matter
COMPONENT OF SCIENCE: Science in Society
To enable students to demonstrate positive attitudes toward science in solving problems and making personal decisions about issues affecting the individual, society and the environment.
4.6 POLITICS - Basic scientific concepts should be available to all individuals enabling each to make logical decisions for themselves and others.
STANDARD: The learner will understand that:
4.6c - Governments use the development of science and technology in global competition for power and prestige.
BENCHMARK: Government usually has most of the power in making decisions and in enforcing rules for the uses of science and technology.
Pamplets, news clipping, Internet sites on air quality related to air quality in the home and in the community
Suppose you went home this afternoon and your mother had left something cooking on the stove and it was burning and the kitchen was filling with smoke. On your paper write down what would happen when you tried to breathe. (pause) We must have clean air to breathe. Today we will learn some ways to improve the air we breathe both indoors and outdoors.
The air whose quality is important to your health is the air you breathe. Most people in developed areas of the world spend most of their lives indoors. How can we improve our air quality indoors? One way is to allow for good ventilation. When an air pollution monitor was worn by a government official in Washington D.C., large daily variations were noted. The levels found indoors were significantly higher then those outdoors, even in a busy, congested city. The very worst level was found to be in his kitchen at home. (In 3.02 detailed examples of home pollution) A very important way to improve indoor air is to ban smoking indoors. If the outdoor air in any community resembled the self-polluted air that a smoker inhales, it would be considered a national disaster. Not only does smoking hurt the tobacco user, but passive smoke affects others. It has been proven that it increases the risk of respiratory illness in young children and infants and that nonsmokers married to smokers have an elevated risk of lung cancer. Have you ever heard of formaldehyde? Most experiences are with preserving biological specimens in a solution of the gas in a mixture of water and methyl alcohol, but it is also used in the manufacturing of foam insulation, fiberboard, plastics, and other wood products. When making these products, formaldehyde reacts with another chemical, such as urea or phenol, to yield a solid product. Some of the excess formaldehyde has not reacted and the reaction can go backwards to generate formaldehyde gas. One of the largest sources in a home is the insulation used. You should always know what is in the insulation you are using.
Does anyone heat with a wood stove? Wood stoves must be well ventilated. They give off carbon monoxide, nitrogen dioxide and particle matter. Particle matter is the solid particles found in smoke.
An indoor purifier will help filter out some of these hazards but good ventilation and caution are also necessary.
You must leave your house sometime. What about the air outdoors? There have been air quality control laws around for a long time. The first federal legislation was in 1955 and in 1963 Congress enacted the Clean Air Act. These laws were hard to enforce and left up to individual states to monitor them. In 1970 the EPA developed a uniform air quality standard. Amendments also required states to draw up plans and to enforce air quality standards for stationary sources such as factories and power plants.
Some of the strategies used in industry include building taller smokestacks and locating in rural areas. The emissions from these sources must meet certain criteria. The pollutants can be separated from the harmless gases and disposed of properly. The pollutants can be converted to harmless products that can be released into the atmosphere.
In terms of the total quality of pollutants that are emitted into the air, the primary offender is the motor vehicle. A number of measures are used to control the various pollutants that are produced by different components of the automobile. The positive crankcase ventilation system was voluntarily installed in cars in 1971 models. This reduced hydrocarbon emission from the crankcase by channeling crankcase blow-by gases back to the engine where they are burned. Exhaust emissions are more difficult to control. Refinements in engine adjustments have reduced exhaust emissions but at the expense of fuel economy. Exhaust controls were improved by 70% in 1975, when catalytic converters were introduced. These devices chemically change hydrocarbons and carbon monoxide in exhaust into carbon dioxide and water vapor. However, this device work only when unleaded gasoline is used. In the early years people would have these devices removed so they could use cheaper leaded gasoline. It is illegal for these to be removed. Another strategy for controlling automobile emissions is to substitute alcohol for gasoline. Both ethanol (grain alcohol) and methanol (wood alcohol) burn cleaner than gasoline and result in lower emission of carbon monoxide and hydrocarbons.
Another option is phasing out the internal combustion engine in favor of steam or battery powered engines. At present these engines fail to match the internal combustion engine in terms of durability, performance, or cost. By law, the automobile industry has a responsibility to reduce emissions from automobiles. Individuals can contribute to improved air quality by voluntarily restricting use of motor vehicles and keeping them well tuned. Large cities with extreme control problems might decide to enforce restrictions by encouraging car pools, establishing bus lanes, restricting downtown parking, and expanding mass transit. Some cities have enacted mandatory vehicle inspection and maintenance programs.
(Have students make a list of possible pollutants in their homes and school.
The students could compare the exhaust emission of different automobiles by holding filters at tail pipes and filtering the exhausts.
The students could also take a confidential survey of people to see whether they have a catalytic converter on their automobile.)
I want you to figure approximately how many minutes in one week you spend indoors and how many outdoors. (Give students time to calculate). In your lifetime the majority of your time will be indoors. That is why it is important to improve indoor air quality. We will take several indoor pollutants and learn how to control them.
Radon, combustion by-products, and tobacco smoke are common in homes. Radon is the radioactive decomposition product of radium. Many rocks and soils contain tiny concentrations of uranium. Radon is a gas that can diffuse out of the rock or soil and then into the cellar or basement through cracks or openings in the foundation. The radon then mixes with indoor air and is thus inhaled and enters the lungs where it decomposes to form polonium, a radioactive metal. The metal, being a solid, is not exhaled and continues to emit radiation in the lungs. Combustion by-products come from any open flame used such as cooking with gas or candles, etc. and you know where tobacco smoke comes from. The indoor air needs to dilute with fresh outdoor air through ventilation. It could also be filtered with a commercial filtering system. Radon can also be controlled by sealing up cracks in the basement and venting the air to the outdoors with an exhaust fan.
Pollution from formaldehyde could be controlled by thoroughly inspecting any products used in the home that contain fiberboard and wood products and checking what kind of insulation is in your home. These may have to be replaced or removed. Some schools and public buildings have had to remove old asbestos insulation and have it replaced. When buying new materials require labeling of all materials.
Smoking releases carbon monoxide and particles into the air. If a large area was as polluted as a room with one person smoking in it, the area would be in an emergency situation. Ventilation and air filtering help a little, but the only significant help comes from banning all smoking indoors.
Investigate and make a list of any public areas where smoking is banned.
List some ways air quality can be improved.
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time this file has been accessed since 01/06/03.
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