Page i

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2023. Air Quality in Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/27033.

×

TRANSPORTATION INSIGHTS | 2

SUMMARY OF A TCRP INSIGHT EVENT
June 21–22, 2022 | Washington, DC

Air Quality in
Transit Buses

Laura Williams, Rapporteur
Versar, Inc.

Organized by the
Transit Cooperative Research Program
Transportation Research Board

Sponsored by the
Federal Transit Administration
In cooperation with the American Public Transportation Association

Page ii

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2023. Air Quality in Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/27033.

×

Transportation Insights 2

TCRP Project E-13
ISBN 978-0-309-69853-5

COPYRIGHT INFORMATION

Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein.

The Transportation Research Board (TRB) grants permission to reproduce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, APTA, FAA, FHWA, FTA, GHSA, or NHTSA endorsement of a particular product, method, or practice. It is expected that those reproducing the material in this document for educational and not-for-profit uses will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from the National Academies Press.

Cover photo: © Adobe Stock.

NOTICE

This summary was reviewed by the technical panel and accepted for publication according to procedures established and overseen by the Transportation Research Board and approved by the National Academies of Sciences, Engineering, and Medicine.

This event was organized through TRB’s Transit Cooperative Research Program (TCRP) and sponsored by the Federal Transit Administration in cooperation with the American Public Transportation Association. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

Suggested citation: Transportation Research Board. Transportation Insights 2: Air Quality in Transit Buses. Summary of a TCRP Insight Event, June 21–22, 2022. Washington, DC: The National Academies of Sciences, Engineering, and Medicine, 2023.

Page iii

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2023. Air Quality in Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/27033.

×

The National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, nongovernmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research. Dr. Marcia McNutt is president.

The National Academy of Engineering was established in 1964 under the charter of the National Academy of Sciences to bring the practices of engineering to advising the nation. Members are elected by their peers for extraordinary contributions to engineering. Dr. John L. Anderson is president.

The National Academy of Medicine (formerly the Institute of Medicine) was established in 1970 under the charter of the National Academy of Sciences to advise the nation on medical and health issues. Members are elected by their peers for distinguished contributions to medicine and health. Dr. Victor J. Dzau is president.

The three Academies work together as the National Academies of Sciences, Engineering, and Medicine to provide independent, objective analysis and advice to the nation and conduct other activities to solve complex problems and inform public policy decisions. The National Academies also encourage education and research, recognize outstanding contributions to knowledge, and increase public understanding in matters of science, engineering, and medicine.

Learn more about the National Academies of Sciences, Engineering, and Medicine at www.nationalacademies.org.

The Transportation Research Board is one of seven major programs of the National Academies of Sciences, Engineering, and Medicine. The mission of the Transportation Research Board is to provide leadership in transportation improvements and innovation through trusted, timely, impartial, and evidence-based information exchange, research, and advice regarding all modes of transportation. The Board’s varied activities annually engage about 8,000 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. The program is supported by state transportation departments, federal agencies including the component administrations of the U.S. Department of Transportation, and other organizations and individuals interested in the development of transportation.

Learn more about the Transportation Research Board at www.TRB.org.

Page iv

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2023. Air Quality in Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/27033.

×

Planning Committee for the TCRP Insight Event

Tyler Baker, Hatch LTK

Allison Laurie Barrett, BASF Canada

Sean Cagan, Capital Metropolitan Transportation Authority

Kit Conway, Washington Metropolitan Area Transit Authority

Roland Cordero, Foothill Transit

Nathan Edwards, MITRE (formerly), U.S. Partnership for Assured Electronics (current)

Ronald Ester, Massachusetts Bay Transportation Authority

John Gasparine, WSP

Vijay Khawani, Los Angeles County Metropolitan Transportation Authority

Ariel Piedmont, Sound Transit

Cole Pouliot, Independent Consultant

Suriya Vallamsundar, Trinity Consultants

Planning Committee Liaisons

Mohammed Yousuf, Federal Transit Administration

Brian Thomas Alberts, American Public Transportation Association

Planning Panel Liaison Representatives

Jason DeGraw, Oak Ridge National Laboratory

Brian L. Sherlock, Amalgamated Transit Union

Transportation Research Board Staff

Gwen Chisholm-Smith, Program Manager

Mariela Garcia-Colberg, Senior Program Officer

Publications Staff for Transportation Insights

Natalie Barnes, Director of Publications

Heather DiAngelis, Associate Director of Publications

Linda A. Dziobek, Senior Editor

Jennifer J. Weeks, Publishing Projects Manager

Jennifer Correro, Assistant Editor

Page v

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2023. Air Quality in Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/27033.

×

TCRP OVERSIGHT AND PROJECT SELECTION COMMISSION*

CHAIR

Doran J. Barnes

Foothill Transit

VICE CHAIR

Jeanne Krieg

Eastern Contra Costa Transit Authority (retired)

SECRETARY/TREASURER

Jameson Auten

Lane Transit District

IMMEDIATE PAST CHAIR

Paul J. Ballard

Trinity Metro (retired)

MEMBERS

Mallory R. Avis

City of Battle Creek Transit

Alva Carrasco

Burns Engineering

Dorval Ronald Carter, Jr.

Chicago Transit Authority

Desmond Cole

Southeastern Pennsylvania Transportation Authority

Francis “Buddy” Coleman

Clever Devices Ltd.

Ryan I. Daniel

St. Cloud Metro Bus

Faye DiMassimo

Chatham Area Transit

Suzie Edrington

Capital Metro–Austin Public Transit

Carolyn Flowers

InfraStrategies LLC

David Harris

New Mexico Department of Transportation

Betsy Kachmar

Advocate-at-Large

Joseph Leader

Consultant

Bacarra Mauldin

Memphis Area Transit Authority

Erika Mazza

Consultant

Elizabeth Presutti

Consultant

Daniel J. Raudebaugh

Center for Transportation and the Environment

Jeffrey Rosenberg

Amalgamated Transit Union

Bernard Schmidt

Jacksonville Transportation Authority

Vicki L. Shotland

Greater Hartford Transit District

David C. Wilcock

Vanasse Hangen Brustlin, Inc.

Kimberly J. Williams

Metropolitan Transit Authority of Harris County

Nigel H.M. Wilson

MIT

EX OFFICIO MEMBERS

Nuria I. Fernandez

FTA

Neil J. Pedersen

TRB

Stephanie Pollack

FHWA

Paul P. Skoutelas

APTA

Jim Tymon

AASHTO

TOPS COMMISSION STAFF ADVISOR

Arthur L. Guzzetti

APTA

SECRETARY

Christopher J. Hedges

TRB

TRANSPORTATION RESEARCH BOARD 2023 EXECUTIVE COMMITTEE*

OFFICERS

CHAIR: Shawn Wilson, Secretary, Louisiana Department of Transportation and Development, Baton Rouge

VICE CHAIR: Carol A. Lewis, Professor, Transportation Studies, Texas Southern University, Houston

EXECUTIVE DIRECTOR: Victoria Sheehan, Transportation Research Board, Washington, DC

MEMBERS

Michael F. Ableson, CEO, Arrival Automotive–North America, Detroit, MI

James F. Albaugh, President and Chief Executive Officer, The Boeing Company (retired), Scottsdale, AZ

Carlos M. Braceras, Executive Director, Utah Department of Transportation, Salt Lake City

Douglas C. Ceva, Vice President, Customer Lead Solutions, Prologis, Inc., Jupiter, FL

Nancy Daubenberger, Commissioner of Transportation, Minnesota Department of Transportation, St. Paul

Marie Therese Dominguez, Commissioner, New York State Department of Transportation, Albany

Ginger Evans, President, Tower Consulting, LLC, Arlington, VA

Nathaniel P. Ford, Sr., Chief Executive Officer, Jacksonville Transportation Authority, Jacksonville, FL

Diane Gutierrez-Scaccetti, Commissioner, New Jersey Department of Transportation, Trenton

Stephen W. Hargarten, Professor, Emergency Medicine, Senior Injury and Policy Advisor, Comprehensive Injury Center; Founding Dean, Office of Global Health, Medical College of Wisconsin, Milwaukee

Chris T. Hendrickson, Hamerschlag University Professor of Engineering Emeritus, Carnegie Mellon University, Pittsburgh, PA

Randell Iwasaki, Leader of State and Local Transportation, Amazon Web Services, Walnut Creek, CA

Ashby Johnson, Executive Director, Capital Area Metropolitan Planning Organization (CAMPO), Austin, TX

Joel M. Jundt, Secretary of Transportation, South Dakota Department of Transportation, Pierre

Drew Kodjak, Executive Director, International Council on Clean Transportation, Washington, DC

Hani S. Mahmassani, W.A. Patterson Distinguished Chair in Transportation; Director, Transportation Center, Northwestern University, Evanston, IL

Michael R. McClellan, Vice President, Strategic Planning, Norfolk Southern Corporation, Norfolk, VA

Russell McMurry, Commissioner, Georgia Department of Transportation, Atlanta

Craig E. Philip, Research Professor and Director, VECTOR, Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN

Steward T.A. Pickett, Distinguished Senior Scientist, Cary Institute of Ecosystem Studies, Millbrook, NY

Leslie S. Richards, General Manager, Southeastern Pennsylvania Transportation Authority (SEPTA), Philadelphia

Susan A. Shaheen, Professor and Co-Director, Transportation Sustainability Research Center, University of California, Berkeley

EX OFFICIO MEMBERS

Michael R. Berube, Deputy Assistant Secretary for Sustainable Transportation, U.S. Department of Energy, Washington, DC

Shailen Bhatt, Administrator, Federal Highway Administration, U.S. Department of Transportation, Washington, DC

Amit Bose, Administrator, Federal Railroad Administration, Washington, DC

Tristan Brown, Deputy Administrator, Pipeline and Hazardous Materials Safety Administration, U.S. Department of Transportation, Washington, DC

Ann Carlson, Acting Administrator, National Highway Traffic Safety Administration, Washington, DC

Steven Cliff, Executive Officer, California Air Resources Board, Sacramento, CA

Nuria I. Fernandez, Administrator, Federal Transit Administration, Washington, DC

LeRoy Gishi, Chief, Division of Transportation, Bureau of Indian Affairs, U.S. Department of the Interior, Germantown, MD

William H. Graham, Jr. (Major General, U.S. Army), Deputy Commanding General for Civil and Emergency Operations, U.S. Army Corps of Engineers, Washington, DC

John T. Gray II, Senior Vice President, Policy and Economics, Association of American Railroads, Washington, DC

Robert C. Hampshire, Deputy Assistant Secretary for Research and Technology, U.S. Department of Transportation, Washington, DC

Robin Hutcheson, Administrator, Federal Motor Carrier Safety Administration, Washington, DC

Eleftheria Kontou, Assistant Professor, University of Illinois at Urbana–Champaign, Urbana, and Chair, TRB Young Members Coordinating Council

Billy Nolen, Acting Administrator, Federal Aviation Administration, U.S. Department of Transportation, Washington, DC

Karl Simon, Director, Transportation and Climate Division, U.S. Environmental Protection Agency, Washington, DC

Paul P. Skoutelas, President and CEO, American Public Transportation Association, Washington, DC

Polly Trottenberg, Deputy Secretary of Transportation, U.S. Department of Transportation, Washington, DC

Jim Tymon, Executive Director, American Association of State Highway and Transportation Officials, Washington, DC

__________________

^* Membership as of February 2023.

Page vi

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2023. Air Quality in Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/27033.

×

Preface

“Air Quality in Transit Buses,” held virtually on June 21–22, 2022, brought together senior transportation executives; representatives from federal, state, and local government; and representatives from technology, consulting, academia, and engineering to discuss opportunities and the challenges of implementing air quality control in buses. The Transportation Research Board’s (TRB’s) Transit Cooperative Research Program (TCRP) organized the event under TCRP Project E-13 as part of its series of convening activities titled “TCRP Insight Events.”

TCRP Insight Events are forums that foster dialogue between professionals across sectors, institutions, and industries. TCRP Insight Events convene transit industry leaders and subject matter experts in various fields to encourage discussion and promote broader and deeper insight on topics of significance to public transit agencies. These in-depth gatherings are designed to promote communication and collaboration, foster innovation, and help identify areas of future interest and research, especially for topics of emerging importance.

This report, prepared by rapporteur Laura Williams of Versar, Inc., is a compilation of the presentations and a factual summary of the ensuing discussions at the event. The planning committee for the event was solely responsible for organizing “Air Quality in Transit Buses,” identifying speakers, and coordinating activities during the event. The views contained in these proceedings are those of individual participants at the TCRP Insight Event and do not necessarily represent the views of all participants, the planning committee, TRB, or the National Academies of Sciences, Engineering, and Medicine.

This report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purposes of this independent review are to provide candid and critical comments that will help ensure the published report is as sound as possible and to ensure that the document meets institutional standards for clarity, objectivity, and responsiveness to the project charge.

TRB thanks the following individuals for their review of the proceedings: Andrew Krum and Brian L. Sherlock. TRB also thanks staff reader Courtney Hill. Responsibility for the final content rests entirely with the authors and the institutions.

Page viii

Suggested Citation:"Front Matter." National Academies of Sciences, Engineering, and Medicine. 2023. Air Quality in Transit Buses. Washington, DC: The National Academies Press. doi: 10.17226/27033.

×

Acronyms and Abbreviations

ACH	air changes per hour
APTA	American Public Transportation Association
ASHRAE	American Society of Heating, Refrigerating and Air-Conditioning Engineers
BART	Bay Area Rapid Transit
CDC	Centers for Disease Control and Prevention
CFD	computational fluid dynamics
CFM	cubic feet per minute
COVID-19	SARS-CoV-2 virus
EPA	Environmental Protection Agency
EUI	energy use intensity
FIFRA	Federal Insecticide, Fungicide, and Rodenticide Act
HVAC	heating, ventilation, and air conditioning
IAQ	indoor air quality
LED	light-emitting diode
MERV	minimum efficiency reporting value
NIOSH	National Institute for Occupational Safety and Health
OEM	original equipment manufacturer
OSHA	Occupational Safety and Health Administration
PCO	photocatalytic oxidation
PCR	polymerase chain reaction
TB	tuberculosis
TCRP	Transit Cooperative Research Program
TRB	Transportation Research Board
UV	ultraviolet light
UV-C	short-wavelength ultraviolet light (but far-UV-C light)
UVGI	ultraviolet germicidal irradiation
VTTI	Virginia Tech Transportation Institute