Vehicle exhaust emissions present the greatest pollutant hazard in the form of____________________?
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Answer: A. CO
Explanation
Incomplete combustion in internal combustion vehicle engines produces significant quantities of carbon monoxide. Carbon monoxide is a colorless odorless gas that binds hemoglobin and starves tissues of oxygen. This toxic gas presents the single greatest pollutant hazard in dense urban traffic environments. Automobile exhaust emissions contain unburned hydrocarbons nitrogen oxides and carbon monoxide. Traffic congestion creates localized pollutant hot spots along busy urban street canyons. Catalytic converters reduce emissions but cold starts and heavy acceleration still release carbon monoxide.
Environmental protection agencies monitor urban air quality to protect public health from vehicle smog. Urban planners design pedestrian zones and bypass tunnels to reduce human exposure to traffic exhaust. Stringent emission standards force automobile manufacturers to improve engine combustion efficiency. Sulphur dioxide originates primarily from industrial combustion and coal fired power plant emissions. Carbon dioxide is a greenhouse gas contributing to global climate change rather than acute toxicity. Ozone is a secondary photochemical pollutant formed when sunlight reacts with volatile organic compounds.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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