Federal standards dictate how much pollution autos may emit, and automakers decide how to achieve the pollution limits. The emission reductions of the 1970's came about because of fundamental improvements in engine design, plus the addition of charcoal canisters to collect hydrocarbon vapors and exhaust gas recirculation valves to reduce nitrogen oxides.
The advent of "first generation" catalytic converters in 1975 significantly reduced hydrocarbon and carbon monoxide emissions. The use of catalytic converters provided a huge indirect benefit as well. Because lead inactivates the catalyst, 1975 saw the widespread introduction of unleaded gasoline. This resulted in dramatic reductions in ambient lead levels and alleviated many serious environmental …show more content…
In response to tighter standards, manufacturers equipped new cars with even more sophisticated emission control systems. These systems generally include a new catalyst, plus an on board computer and oxygen sensor. This equipment helps optimize the efficiency of the catalytic converter.
Efforts by government and industry since 1970 have greatly reduced typical vehicle emissions. Since then, however, the number of miles we drive has more than doubled. The increase in travel has offset much of the emission control progress.
The net result is a modest reduction in each automotive pollutant except lead, for which aggregate emissions have dropped by more than 95 percent.
From Wikipedia, the free encyclopedia
List the following sources of emissions must be considered:
Life cycle emissions: These are produced in activities associated with the manufacturing, maintenance, and disposal of the automobile and include such items as:
1. Manufacturing plant power requirements
2. Volatile solvents utilized in the manufacturing process (auto paint finishes, etc)
3. Outgassing of synthetic materials utilized to reduce weight and simplify manufacturing
4. Maintenance requirements such as oil and filter changes, battery replacement,
The advent of "first generation" catalytic converters in 1975 significantly reduced hydrocarbon and carbon monoxide emissions. The use of catalytic converters provided a huge indirect benefit as well. Because lead inactivates the catalyst, 1975 saw the widespread introduction of unleaded gasoline. This resulted in dramatic reductions in ambient lead levels and alleviated many serious environmental …show more content…
In response to tighter standards, manufacturers equipped new cars with even more sophisticated emission control systems. These systems generally include a new catalyst, plus an on board computer and oxygen sensor. This equipment helps optimize the efficiency of the catalytic converter.
Efforts by government and industry since 1970 have greatly reduced typical vehicle emissions. Since then, however, the number of miles we drive has more than doubled. The increase in travel has offset much of the emission control progress.
The net result is a modest reduction in each automotive pollutant except lead, for which aggregate emissions have dropped by more than 95 percent.
From Wikipedia, the free encyclopedia
List the following sources of emissions must be considered:
Life cycle emissions: These are produced in activities associated with the manufacturing, maintenance, and disposal of the automobile and include such items as:
1. Manufacturing plant power requirements
2. Volatile solvents utilized in the manufacturing process (auto paint finishes, etc)
3. Outgassing of synthetic materials utilized to reduce weight and simplify manufacturing
4. Maintenance requirements such as oil and filter changes, battery replacement,