Award Date


Degree Type


Degree Name

Master of Engineering (ME)


Civil and Environmental Engineering

First Committee Member

Dave James

Number of Pages



AP-42 Emission Factors were analyzed for trends over time and dependence on roadway classification and improvements. Local roads presented a significant decrease in Emission Factor over time for pooled data. Local road Emission Factors were significantly higher than Collector and Minor Arterial Emission Factors for pooled data. Differences in AP-42 Emission Factor between the Collectors and Minor arterials were not statistically significant; however the differences between Local and either Collector or Minor arterials were statistically significant. Individual analysis of each road show that two Locals and two Minor arterials (among 30 different sites) presented a significant decrease with time. Year by year statistical analysis of effects of roadway improvements on emissions factors showed that only twice (since 1999) roads with improved shoulder presented a significant lower Emission Factor than roads with unimproved shoulder; Aerodynamic shear applied by vacuum cleaner, cars and DRI's Mini-PI-SWERL(TM) were estimated and compared. Shear values for vacuum cleaners were found to generally exceed the Mini-PI-SWERL(TM) shears by a factor of 6.9 and were over 300 times as great as estimated shear values developed by vehicles. Because of higher shear it is likely that the AP-42 emissions are overestimating PM 10 emissions for paved road. Laboratories tests showed that silt recovery increased with aerodynamic shear.


Emissions; Estimation; Improved; Paved Road; Techniques

Controlled Subject

Environmental sciences; Civil engineering

File Format


File Size

8355.84 KB

Degree Grantor

University of Nevada, Las Vegas




If you are the rightful copyright holder of this dissertation or thesis and wish to have the full text removed from Digital Scholarship@UNLV, please submit a request to and include clear identification of the work, preferably with URL.


IN COPYRIGHT. For more information about this rights statement, please visit