Alex Bigazzi, a 2014 NITC dissertation fellow and graduate of Portland State University's Civil and Environmental Engineering Ph.D. program, has published a paper based on his NITC-funded research in Environmental Science & Technology, a journal of the American Chemical Society (ACS).
See ACS coverage of the project here.
Bigazzi's research evaluates the concentration of air pollution encountered by cyclists in Portland, Oregon.
In the study, volunteer research subjects rode bicycles equipped with instruments to collect high-resolution bicycle, rider, traffic and environmental data.
Participants rode a variety of routes including bicycle lanes on primary and secondary arterials, bicycle boulevards, off-street paths and mixed-use roadways. They were told to ride at a pace and exertion level typical for utilitarian travel, and breath biomarkers were used to record the amount of traffic-related pollution present in each cyclist’s exhalations.
This research was the focus of Bigazzi's dissertation, Bicyclists’ Uptake of Traffic-Related Air Pollution: Effects of the Urban Transportation System, published by NITC in December 2014. It was related to an earlier project...Read more
Active travel such as walking and bicycling can lead to health benefits through an increase in physical activity. At the same time, more active travelers breath more and so can experience high pollution inhalation rates during travel. This webinar will review the state of knowledge about how roadway and traffic characteristics impact air pollution risks for bicyclists, including the latest PSU research quantifying bicyclists' uptake of traffic-related air pollution using on-road measurements in Portland. The PSU research team including Alex Bigazzi, Jim Pankow, and Miguel Figliozzi quantified bicyclist exposure concentrations on different types of roadways, respiration responses to exertion level, and changes in blood concentrations of pollutants. Implications for planners, engineers, and policy-makers will be discussed, including guidance for more pollution-conscious bicycle network planning and design. Additionally, ways for individual travelers to reduce their air pollution risks will be discussed.
This 60-minute webinar is eligible for one hour of training which equals 1 CM or 1 PDH. NITC...Read more
Health risks associated with air pollution uptake while bicycling are often cited as a potential drawback to increased bicycling in cities. This seminar will provide an overview of how roadway and travel characteristics impact bicyclists' uptake of traffic-related air pollution. Specific considerations for planners and designers of urban transportation systems to mitigate risks for travelers will be discussed. In addition, the extent to which bicyclists themselves can unilaterally reduce their pollution uptake will be described. This seminar synthesizes findings from a recently completed doctoral dissertation at Portland State University and from the broader literature.
The video begins at 1:49.
Abstract: Policy-makers, researchers, and activists often assume that traffic congestion mitigation results in reduced motor vehicle emissions without proper justification or quantification. This research investigates under which conditions that assumption is valid by comparing trade-offs between increased efficiency and induced travel. Analyses include investigation of varying vehicle fleets - including advanced-drivetrain vehicles. Results demonstrate that higher levels of congestion do not necessarily increase emissions, nor will congestion mitigation inevitably reduce emissions. These results apply for both roadway capacity expansions and traffic flow improvement projects. We compare the emissions effects of various congestion and emissions mitigation strategies, with particular attention to the roll of trucks and the potential of truck-only facilities. Congestion performance measures are also compared for applicability to emissions trends.
The video begins at 0:51.
Alex Bigazzi, Miguel Figliozzi, Portland State University
The video begins at 1:44.
Oliver Smith (USP PhD) - Peak of the day or the daily grind? Commuting and subjective well-being
To understand the impact of daily travel on personal and societal well-being, measurement techniques that go beyond satisfaction-based measures of travel are used. Such metrics are increasingly important for evaluating transportation and land-use policies. This study examines commute well-being, a multi-item measure of how one feels about the commute to work, and its influences using data from a web-based survey that was distributed to Portland, Oregon, U.S.A. workers. Valid surveys (n=828) were compiled from three roughly equally sized groups based on mode: bike, transit and car users. Average distances between work and home varied significantly among the three groups. Descriptive results show that commute well-being varies widely across the sample. Those who bike to work have significantly higher commute well-being than transit and car commuters. A multiple linear regression model shows that along with travel mode, traffic congestion, travel time, income, health, job satisfaction and residential satisfaction also play important individual roles in shaping commute well-being. While more analysis is needed, these results support findings in previous research that commuting by bike enhances well-being while congestion detracts from well-being. Implications for future research and...Read more
Summary: Urban bicyclists’ uptake of traffic-related air pollution is still not well quantified, due to a lack of direct measurements of uptake and a lack of analysis of the variation in uptake. This paper describes and establishes the feasibility of a novel method for measuring bicyclists’ uptake of volatile organic compounds (VOC) by sampling breath concentrations. Early results from the data set demonstrate the ability of the proposed method to generate findings for transportation analysis, with statistically significant exposure and uptake differences from bicycling on arterial versus bikeway facilities for several traffic-related VOC. These results provide the first empirical evidence that the usage of bikeways (or greenways) by bicyclists within an urban environment can significantly reduce uptake of dangerous traffic-related gas pollutants. Dynamic concentration and respiration data reveal unfavorable correlations from a health impacts perspective, where bicyclists’ respiration and travel time are greater at higher-concentration locations on already high-concentration roadways (arterials).
Bio: Alex Bigazzi is a Ph.D. candidate in Transportation Engineering at PSU, where he is also teaching a class on transportation emissions modeling. His dissertation investigates how urban bicyclists...
Portland State University engineering doctoral student Alex Bigazzi has developed a new course aimed at giving transportation engineers experience running emissions models. The course, Transportation Emissions Modeling, is offered through the Department of Civil and Environmental Engineering.
The practical nature of the course sets it apart from the few emissions courses offered at other universities, Bigazzi said. “Those tend to be on the policy side or the environmental side,” he said. “This is unique in trying to help engineers more than policymakers or future policymakers.”
The course fits with both Bigazzi’s own experience and Portland State’s faculty research strength in emissions and modeling. The university already offers an air quality course, but Bigazzi’s offering focuses narrowly on emissions from motor vehicles.
Students spent the first half of the inaugural course learning context for the models, including when they are used and what they can do. “There are federal requirements to do these models for all serious transportation projects,” Bigazzi said. “People need to understand what goes into them and how accurate they can be.”
Because emissions models aren’t as complex mathematically as other models, and...Read more