1 Air Pollution Automobile Emissions: An Overview Emissions from an individual car <<< smokestack But multiply emissions by millions of vehicles Driving a private car is probably a typical citizen's most "polluting" daily activity Source: EPA 400-F August 1994 Fact Sheet OMS-5

2 Primary Types of Air Pollutants Carbon Monoxide (CO) Volatile Organic Compounds (VOCs) Oxides of Nitrogen (NOx) Sulfur Dioxide (SO 2 ) Particulate Matter (PM 10 ) Lead (Pb) Fundamentals of Air Pollution and Motor Vehicle Emissions John T. White, EPA

3 Calculating Emissions Total emissions = emission rate x vehicle activity Example: Emission rate from MOBILE6 for CO is 35 grams/mile A city has 1000 miles of roadway and an average of 2000 vehicles per mile per day use the road. Calculate total CO emission for 1 day. Total CO = 35 g/mile (1000 miles x 2000 vehicles) = 70,000 kg of CO

4 Emission Rates Amount of emission produced by a source per unit of time, distance, etc EPA models Mobile sources: MOBILE6 Vehicle Activity Number of vehicles VMT etc

5 Emission rates are in grams/mile/vehicle

6

7

8 Calculate emissions for 10 mile roadway with 100 passenger cars and 20 trucks at 60 mph

9 NOx emission rate is 13 g/mile for HDT and 1 g/mile for PC

10 NOx emission rate is 13 g/mile for HDT and 1 g/mile for PC Calculate emissions for 10 mile roadway with 100 passenger cars and 20 trucks at 60 mph 100 pc x 1 g/mile x 10 mile = 1000 grams of NOx for PC 20 x 13 g/mile x 10 mile = 2600 grams of NOx for HDT 3600 grams total = 3.6 kg