[Senate Hearing 118-459]
[From the U.S. Government Publishing Office]


                                                        S. Hrg. 118-459

                     EXAMINING THE STATE OF AIR QUALITY 
                         MONITORING TECHNOLOGY

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                                HEARING

                               BEFORE THE

                              COMMITTEE ON
                      ENVIRONMENT AND PUBLIC WORKS

                          UNITED STATES SENATE

                    ONE HUNDRED EIGHTEENTH CONGRESS

                             SECOND SESSION

                               __________

                             APRIL 10, 2024

                               __________

  Printed for the use of the Committee on Environment and Public Works
  
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]  


        Available via the World Wide Web: http://www.govinfo.gov
        
                                __________

                   U.S. GOVERNMENT PUBLISHING OFFICE                    
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               COMMITTEE ON ENVIRONMENT AND PUBLIC WORKS

                    ONE HUNDRED EIGHTEENTH CONGRESS
                             SECOND SESSION

                  THOMAS R. CARPER, Delaware, Chairman
          SHELLEY MOORE CAPITO, West Virginia, Ranking Member

BENJAMIN L. CARDIN, Maryland         KEVIN CRAMER, North Dakota
BERNARD SANDERS, Vermont             CYNTHIA M. LUMMIS, Wyoming
SHELDON WHITEHOUSE, Rhode Island     MARKWAYNE MULLIN, Oklahoma
JEFF MERKLEY, Oregon                 PETE RICKETTS, Nebraska
EDWARD J. MARKEY, Massachusetts      JOHN BOOZMAN, Arkansas
DEBBIE STABENOW, Michigan            ROGER WICKER, Mississippi
MARK KELLY, Arizona                  DAN SULLIVAN, Alaska
ALEX PADILLA, California             LINDSEY O. GRAHAM, South Carolina
JOHN FETTERMAN, Pennsylvania

               Courtney Taylor, Democratic Staff Director
               Adam Tomlinson, Republican Staff Director
                            
                            C O N T E N T S

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                                                                   Page

                             APRIL 10, 2024
                           OPENING STATEMENTS

Carper, Hon. Thomas R., U.S. Senator from the State of Delaware..     1
Capito, Hon. Shelley Moore, U.S. Senator from the State of West 
  Virginia.......................................................     3

                               WITNESSES

Hammad, Omar, Environmental Policy Analyst, Congressional 
  Research Service, Library of Congress..........................     6
    Prepared statement...........................................     8
    Responses to additional questions from Senator Carper........    24
Obermann, William ``Bill'', Air Program Supervisor, Department of 
  Public Health and Environment, City and County of Denver.......    28
    Prepared statement...........................................    30
    Responses to additional questions from Senator Carper........    36
Austin, Anne, Former Principal Deputy Assistant Administrator for 
  the Office of Air and Radiation, U.S. Environmental Protection 
  Agency.........................................................    40
    Prepared statement...........................................    42
    Responses to additional questions from Senator Capito........    46

                          ADDITIONAL MATERIAL

Letter from Anne L. Idsal, EPA of Washington DC, to EPA Regional 
  Administrators regarding Air Sensors...........................    57
From the U.S. Environmental Protection Agency: The Enhanced Air 
  Sensor Guidebook, Andrea Clements and Rachelle Duvall..........    59
Letters to Senator Carper and Senator Capito from:
    Tall Timbers.................................................   268
    Climate & Wildfire Institute.................................   269

 
        EXAMINING THE STATE OF AIR QUALITY MONITORING TECHNOLOGY

                              ----------                              


                       WEDNESDAY, APRIL 10, 2024

                                       U.S. Senate,
                 Committee on Environment and Public Works,
                                                    Washington, DC.
    The committee met, pursuant to notice, at 10:03 a.m. in 
room 406, Dirksen Senate Office Building, Hon. Thomas R. Carper 
(chairman of the committee) presiding.
    Present: Senators Carper, Capito, Markey, Kelly, Padilla, 
Sullivan.

          OPENING STATEMENT OF HON. THOMAS R. CARPER, 
            U.S. SENATOR FROM THE STATE OF DELAWARE

    Senator Carper. Good morning, everyone. I am pleased to 
call this hearing to order.
    Though air pollution can be a complex topic, as we all 
know, the goal of this hearing is pretty simple. It is to 
examine the role that low-cost air quality sensors can play in 
helping us collect more data about the quality of our air so 
that we can do a better job of protecting public health and 
engaging communities in those responses. That is really what we 
are up to.
    Today, we will discuss how new air quality sensor 
technology is making it possible for State and local air 
quality agencies to work with businesses and with their 
communities. In particular, we are going to hear about how low-
cost sensor technology is supplementing existing data gathering 
and how the technologies are evolving, as well as how local 
regulators are incorporating these sensors into their own work.
    Low-cost air quality sensors are becoming an important tool 
in the toolbox of air agencies, but it is important for us to 
distinguish what their limitations are so that they can be 
integrated successfully into community-level public health 
initiatives. As you know, almost anybody can buy one of these 
sensors, almost anyone. They cost a couple of hundred dollars.
    The Environmental Protection Agency refers to these low-
cost devices as sensors. They should not be confused with 
monitors that our States use to regulate air quality under EPA 
guidance. This distinction between sensors and monitors is 
important, so let me just repeat it. Today, we are going to be 
talking about sensors, which are low-cost tools to collect data 
on specific pollutants. We are not talking about the monitors 
that States use, our States, my State, and other States here, 
use for regulation under EPA direction.
    Low-cost air quality sensors are not replacing regulatory 
monitors. Regulatory monitors are far more sophisticated. They 
cost tens of thousands of dollars and are the backbone of EPA's 
ability to regulate air quality across this Country of ours.
    Many of us already have low-cost air quality sensors in our 
own homes. Carbon monoxide detectors and smoke detectors 
``sniff'' the air and alert us when a problem is detected. The 
air quality sensors that we are going to discuss today work 
pretty much the same way.
    As members of this committee have heard me oftentimes say, 
everything I do, I know I can do better. I think that is true 
for just about all of us, and it is also true for reducing air 
pollution. We as a Nation can and must do more to address 
pollutants in our air. Despite our Nation's significant strides 
since passing the Clean Air Act of 1970, air pollution still 
negatively impacts far too many Americans, especially in low-
income communities, including communities of color.
    The Center for Air, Climate, and Energy Solutions found 
that people of color are disproportionately exposed to an air 
pollutant called fine particulate matter, also known to most of 
us as soot. Exposure to these small but powerful pollutants is 
linked to lung and heart problems, especially for our kids or 
people with chronic respiratory diseases. The good news is that 
low-cost air quality sensors can help detect this kind of 
pollution, and those sensors are being used appropriately in a 
growing number of communities.
    I believe we have a moral obligation to ensure that all 
Americans, no matter what their ZIP code might be, are free 
from the burden of pollution, air pollution in particular. That 
means equipping communities with tools to improve individuals' 
access to information about the quality of their air. Sensors 
help us do that.
    Some of you might recall that this committee held a hearing 
in July 2022 that discussed the risks of living near or 
downwind of facilities that emit air pollution. Harmful air 
pollutants disproportionately affect these so-called front-line 
communities, but many Americans today do not even know they are 
being exposed to dangerous levels of air pollution. That is why 
sensors are critical, because they sniff the air and detect 
pollutants that the human eye or the human nose cannot detect. 
This technology is getting better and more affordable by the 
day.
    Collecting local air data helps States, it helps tribes, it 
helps communities find pollution hotspots and identify 
facilities that may be generating excess pollution. Low-cost 
sensors also save air agencies money by enabling them to direct 
resources to where the worst pollution is.
    As I often say, find out what works and do more of that. 
Today, we will hear from one of our witnesses about what is 
working with low-cost air quality sensors in, among other 
places, Denver, Colorado, one of the best examples of a local 
air agency working proactively with health care organizations, 
with schools, and with neighborhoods.
    In other places across our Country, cities and local groups 
are working with their air regulators at the State level. For 
example, Utah's Department of Environmental Quality is 
partnering with the University of Utah, as well as with other 
State and local organizations, to stand up a new air quality 
sensor program on the west side of Salt Lake Valley. This 
program will provide almost instant local air quality 
information through air maps and through alerts.
    These sensors complement regulatory monitors. For example, 
during the wildfires last summer in Delaware, the Delaware 
Department of Natural Resources and Environmental Control, we 
call it DNREC, used data from 11 regulatory monitors, data from 
the National Oceanic and Atmospheric Administration, and data 
from low-cost sensors to track air pollution. Using all three 
sources, DNREC was able to quickly issue public health 
advisories for vulnerable residents.
    In closing, clean air is good for human health. It is good 
for our economy, and it is good for our planet. It is good for 
all of us. We look forward to hearing today from our colleagues 
as they arrive and from our witnesses on the ways in which low-
cost air quality sensors can help us reduce air pollution and 
protect public health.
    Before I turn to Senator Capito, I want to thank not just 
our witnesses for being here and testifying today and preparing 
for this hearing, I want to thank our staff for helping to find 
you and to convince you to come today and to share some 
thoughts and responses to some of our questions. We appreciate 
the good staff work that has been done.
    With that, let me turn to our Ranking Member, Senator 
Capito, for her opening statement. Senator Capito, you are 
recognized.

        OPENING STATEMENT OF HON. SHELLEY MOORE CAPITO, 
          U.S. SENATOR FROM THE STATE OF WEST VIRGINIA

    Senator Capito. Thank you, Chairman Carper, and thank you 
all for being here with us today, and I appreciate the travel, 
and I appreciate the expertise that you will bring.
    I think we can all agree that clean air is vital to the 
health and well-being of Americans across the Nation. However, 
I am a bit concerned about the Administration and some of the 
neglect I have seen in the major flaws in the air monitoring 
data quality. It seems as though the Administration is 
prioritizing an agenda while misallocating taxpayers' dollars 
on projects that have limited benefits to our public health and 
welfare.
    First, I think it is important to acknowledge that 
Americans enjoy some of the cleanest air in the world and 
recognize just how much air pollution in the United States has 
been reduced. According to the EPA, between 1980 and 2022, the 
combined emissions of criteria air pollutants and precursor 
pollutants was reduced by 73 percent. Hazardous air pollutant 
emissions have also similarly declined.
    Despite this fact, many Americans are led to believe 
through inaccurate claims that our air quality is getting 
worse, when, in fact, air quality has significantly improved 
and can get better. Congress has made significant investments 
to support the ambient air quality monitoring network. The 
Federal Government partners with States, localities, and tribes 
to build and operate the system. This network is comprised of 
official stationary air monitors that gather data to inform 
regulatory decisions and determine regulatory compliance.
    While use of these official monitors has been generally 
successful, deficiencies with one model's accuracy and 
reliability demonstrate the need to ensure that the monitoring 
system is maintained at the highest standards and is the most 
accurate it can be.
    One year ago, EPA modified a measurement method on the 
Teledyne PM Mass Monitory used to track and measure particulate 
matter. These monitors are crucial to inform potential 
regulatory actions undertaken by the EPA and the States, 
including implementation of the National Ambient Air Quality 
Standards, or the NAAQS.
    Peer-reviewed analysis reported that the monitors had led 
to over-inflated measures of fine particulate matter, or PM 
2.5. In other words, the monitors led the EPA and States to 
believe that the air quality was actually worse than it 
actually was. These artificially high readings date all the way 
back to 2017 when they were first deployed. Those Teledyne 
monitors had a significantly high bias relative to other 
monitors, including the gold standard reference monitors that 
the Chairman spoke about.
    On February 14th of this year, the EPA issued a proposal to 
retroactively modify PM 2.5 data reported from the Teledyne 
monitors from when they were first deployed from the years of 
2017 through April 2023. The EPA proposal notes that more than 
400 Teledyne monitors in our official ambient air monitoring 
network were consistently producing PM 2.5 data that was 20 
percent higher than the real concentration levels.
    To be clear, this level of inaccuracy could be stated as 
unprecedented. It is absolutely critical that EPA prioritize 
correcting this unprecedented error, which they are doing, and 
refocus on high-quality, accurate monitoring data that is 
relied on for regulatory compliance. This is where the EPA's 
focus should be in a monitoring context before the agency 
promotes the use of emerging and less accurate sensors.
    Despite the challenges faced by the existing network used 
for regulatory purposes, there has been a choice to prioritize 
funding for less-accurate, difficult to use, low-cost monitors. 
The partisan American Rescue Plan and Inflation Reduction Act 
funded the use of less accurate and reliable low-cost air 
quality sensors.
    A recent GAO report identified key challenges and data 
deficiencies associated with use of those low-quality air 
sensors. GAO found that users face difficulty understanding the 
capabilities, operations, and maintenance requirements and 
accuracy of those sensors.
    Particularly, GAO noted users often lack the knowledge to 
select the right sensors or deploy them in a way that best fits 
their intended use to gain accurate and actionable data. This 
leads to confusion when the data lacks the high degree of 
confidence necessary to make regulatory decisions and can cause 
misunderstandings about the concentration of air pollutants 
that are affecting our local communities.
    Of particular concern, GAO points out that the EPA has not 
taken basic steps to address issues with sensor use, such as 
issuing guidance on how to make the sensors more usable for 
communities. This confusion can undermine confidence in EPA and 
State regulatory actions, as well as cause our communities and 
residents to panic about their air quality and misallocated 
resources.
    I am concerned that spending more money on new, unproven, 
and inaccurate monitors that can not be used reliably to direct 
our regulatory action will at best be a waste of money or a 
misplaced priority. Instead, we need to make improvements in 
the existing monitoring network so that we can build on the 
substantial progress that have made to improve our air quality.
    With that, I yield back, Mr. Chair.
    Senator Carper. Thank you, ma'am.
    We are now going to turn to our panel of witnesses. I had a 
chance to meet all of you personally and to welcome you. We are 
delighted that you were able to come today.
    First of all, I am going to start off with Mr. Omar Hammad. 
Has anyone ever mispronounced your name?
    Mr. Hammad. Often.
    [Laughter.]
    Senator Carper. Okay. We will try not to do that today. Mr. 
Hammad is an analyst in environmental policy in the Research 
Science and Industry Division of the congressional Research 
Service, which does such great service for all of our Country 
and certainly for folks on this committee. I understand that 
your work focuses primarily on environmental policy issues, 
including the Clean Air Act, indoor air quality, the National 
Environmental Policy Act, and environmental permitting. Before 
joining CRS, Mr. Hammad worked in the Air Progress Branch at 
the Environmental Protection Agency in Region 2.
    Our second witness is Mr. Bill Obermann. Mr. Obermann, good 
to see you. He is an Air Program Supervisor at the Denver 
Department of Public Health and Environment. In this role, I am 
told that Mr. Obermann manages the Denver Department of Public 
Health and Environment's Love My Air Program. I love that 
title, Love My Air Program.
    Love My Air is a city-led air quality monitoring program 
that provides real-time air quality information and education 
to residents of Denver. Mr. Obermann has been with the City 
since 2019, but has over 25 years of experience in air quality 
and transportation planning industries.
    Third, last but not least, we are going to hear from Ms. 
Anne Austin, who I believe is from Austin. This does not happen 
every day; it is pretty cool. We are going to hear from you, 
Ms. Austin.
    I understand you are the former Principal Deputy Assistant 
Administrator for the Office of Air and Radiation at the 
Environmental Protection Agency, and also a former EPA Region 6 
Administrator. Prior to joining EPA, Ms. Austin spent her 
career working for the Texas State government. What did you do, 
working for the Texas State government?
    Ms. Austin. I served at the Texas Commission on 
Environmental Quality and also the Texas General Land Office.
    Senator Carper. Thank you. We thank all of you again for 
your preparation. We thank all of you today for your service 
and for joining us here today to testify and to respond to the 
questions that we have.
    Mr. Hammad, I am going to ask you to please lead us off, 
our lead-off hitter, and proceed with your statement, if you 
are ready. Thank you.

    STATEMENT OF OMAR HAMMAD, ENVIRONMENTAL POLICY ANALYST, 
      CONGRESSIONAL RESEARCH SERVICE, LIBRARY OF CONGRESS

    Mr. Hammad. Chairman Carper, Ranking Member Capito, and 
members of the committee, good morning, and thank you for this 
invitation to appear before you on behalf of the congressional 
Research Service.
    I am Omar Hammad, and I am an analyst in environmental 
policy. My testimony draws on my area of specialization at CRS, 
the Clean Air Act and air quality monitoring.
    The U.S. Environmental Protection Agency, or EPA, defines 
low-cost air sensors as a class of non-regulatory technology 
that is lower is cost, portable, and generally easier to 
operate than the air monitors used for regulatory purposes. 
Some stakeholders have asserted that EPA, State and local air 
agencies should consider the use of low-cost air sensors in 
their regulatory regimes due to competitive costs, increasingly 
better technologies, and expanded coverage.
    This testimony summarizes my written statement that I offer 
for the record and aims to introduce and address the elements 
of this debate. I will discuss ambient air monitors, also known 
as regulatory monitors, and their uses; low-cost air sensors 
and their uses; and the benefits and challenges of both 
technologies.
    Congress recognized the need to address air pollution, 
establishing the Clean Air Act with the purpose of protecting 
and enhancing the quality of the Nation's air resources and 
providing assistance to State and local governments in 
connection with the Air Pollution Prevention and Control 
Programs.
    Under the Clean Air Act, EPA is to issue national ambient, 
or outdoor, air quality standards known as the National Ambient 
Air Quality Standards, or NAAQS for short, for criteria 
pollutants. There are currently six criteria air pollutants: 
particulate matter, ozone, nitrogen dioxide, sulfur dioxide, 
carbon monoxide, and lead.
    Establishing NAAQS does not directly limit emissions or 
compel specific emission controls. Rather, it represents EPA's 
formal judgment regarding the level of ambient air pollution 
that will protect public health with an adequate margin of 
safety.
    Ambient air monitoring is the systemic long-term assessment 
of pollutant levels by measuring the quantity and types of 
pollutants in the surrounding outdoor air. The Clean Air Act 
directs EPA to promulgate regulations that establish an ambient 
air monitoring system throughout the United States.
    Regulatory monitoring sites established primarily by State 
and local air agencies will differ from site to site in the 
number and type of required monitors and pollutants monitored 
at each site. These monitors must meet EPA-designated reference 
or equivalent methods for monitoring.
    Regulators, researchers, communities, and others have 
relied on the network of ambient air monitors to provide the 
data needed for studies, source permitting, NAAQS attainment 
and implementation, air quality alerts, and a host of other 
applications.
    Low-cost air sensors, unlike ambient air monitors, are non-
regulatory and relatively low-priced devices, often priced 
below $2,500 compared to the regulatory monitors that can reach 
prices of up to $50,000. Advancements in technology, micro 
processing capabilities, and miniaturization have led to an 
expansion in the availability of low-cost air sensors to 
measure a variety of air pollutants.
    According to the U.S. Government Accountability Office, the 
use of low-cost air sensors is increasing, driven in part by 
policy and public interest in air quality stemming from 
wildfire smoke, neighborhoods near pollution sources, and other 
concerns.
    EPA is involved in the advancement of low-cost air sensor 
technology, including performance evaluations and best 
practices for effective use. EPA found that these low-cost air 
sensors are generally less accurate than their more expensive 
regulatory counterparts, and stated that data from new air 
sensor instruments should not be used in a regulatory context 
at this time, unless those instruments meet all applicable 
regulatory requirements. EPA did note that they could be used 
in identifying pollution hotspots, providing local community-
scale air monitoring, assisting in the site selection for new 
or relocated regulatory monitors, and conducting scientific 
research.
    Ambient air monitoring networks have provided reliable air 
quality data throughout the Country for decades. In recent 
years, some observers have raised concerns about the increase 
in cost to establish and maintain regulatory monitors. Some 
States and local air agencies assert that low-cost air sensors 
have been successfully used to supplement regulatory monitors 
and fill data gaps. Some contend the sensors help 
decisionmakers address specific needs, such as directing 
limited enforcement resources to achieve emission reductions, 
saving time and money.
    Federal agencies have also made low-cost air sensors 
available for deployment to wildfire locations upon the request 
of firefighting agencies. Stakeholders have noted the low-cost 
sensors have been particularly useful for monitoring wildfire 
smoke in areas without regulatory monitors.
    This concludes my brief remarks. Thank you for the 
opportunity to testify. I look forward to your questions.
    [The prepared statement of Mr. Hammad follows:]
    [GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
    
    Senator Carper. Mr. Hammad, we thank you for your 
testimony. We look forward to asking you some questions in a 
couple of minutes, but let us now turn to Mr. Obermann.
    Mr. Obermann, please proceed. Welcome.

    STATEMENT OF WILLIAM OBERMANN, AIR PROGRAM SUPERVISOR, 
DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT, CITY AND COUNTY OF 
                             DENVER

    Mr. Obermann. Thank you. Good morning, Chairman Carper, 
Ranking Member Capito, and members of the committee and fellow 
panelists. My name is Bill Obermann, I go by Bill. I am an Air 
Program Supervisor at the Denver Department of Public Health 
and Environment.
    I manage the Denver Love My Air Program, and it is a 
program that uses air quality sensors to generate real-time 
pollution measurements for the residents of Denver.
    Denver has been in nonattainment of the EPA's standard for 
ozone since the early 1990's. Add in our population growth, 
wildfires, and the unique geography of our city up against the 
mountains, and you have a persistent ozone pollution issue, as 
well as other pollutants like PM 2.5, which is fine particulate 
matter 2.5 millionths of a meter in diameter, as you know.
    Ozone and PM 2.5 drive our air quality index in Denver and 
the alert system that is then operated by the State. It is as 
common to check the air quality index and scan for air quality 
alerts as it is the weather on a typical summer day in Denver.
    This is the context in which the Love My Air Program exists 
today. It is an example of how local governments are responding 
to educate the public about health and air quality. We take 
real-time data from our sensors and display it on TV screens in 
33 Denver public schools. We also have a smartphone app and 
public website for any member of the public.
    Our information is easy to consume and timely. For example, 
nurses use our information when caring for asthmatic children 
on high air pollution days. Our program started in the schools, 
and what we learned is the most responsive population were the 
nurses. It is best to use these trusted partners to help build 
more awareness around air quality and health. Today, we are 
expanding our program into three local health clinics, because 
they too are trusted partners in health.
    Here we are at a pivotal point. Sensors are providing more 
information on air quality and the official air monitoring 
equipment by EPA in State agencies is also becoming more 
affordable and ready for real-time display. The big questions 
are, how can these monitoring technologies be used to improve 
health outcomes? From our perspective, there are two ways that 
Congress can help.
    The first way is to direct EPA to establish how air quality 
monitoring data from programs like ours can be used to 
complement State analysis and decisions on where to further 
reduce air pollution, especially in ozone and PM 2.5 
nonattainment areas.
    EPA has been issuing guidance, as Mr. Hammad said, on how 
to operate sensor technologies and networks and performance 
testing of different sensor technologies, and all that 
assistance has been very helpful. Denver corrects its sensor 
data using the State monitoring network and using some of those 
EPA protocols.
    We agree with the GAO report that there is clearly an 
emerging need to take the next steps in clarifying how our data 
can be used in a regulatory context. This is even more relevant 
with the EPA's newly revised annual standard for PM 2.5.
    Second, we need to understand how local air quality data 
captured near large industrial facilities, like refineries, can 
be used. EPA has guidance that details how this data needs to 
be collected so it can complement, but not replace, air 
monitoring conducted by State and Federal agencies.
    Today, our air sensor data would not be considered high 
enough quality to use in an enforcement setting, and we agree 
with that conclusion. We use our data almost exclusively today 
as a public health education tool.
    These monitoring technologies are constantly improving, and 
we will continue to get pressure from our residents on how to 
take action with this data in a regulatory context. We are only 
a few short years away from collecting high-quality data at a 
large scale in our neighborhoods and neighborhoods all over the 
Country, particularly those adjacent to industrial sources of 
air pollution.
    I want to reiterate that EPA has been a great partner thus 
far by establishing data quality standards by publishing things 
like the Air Sensor Toolbox online available for everyone. We 
ask that the EPA continue to work directly with us and States 
to start to answer how sensor data can be used in air quality 
planning and assessing facility compliance.
    EPA should continue to support the local level by providing 
monitoring equipment and even helping us install it on the 
ground and help us validate our data. The EPA resources could 
be increased here as more communities start to use this 
technology and more of them become available on the market.
    Thank you for this opportunity to testify today. I look 
forward to your questions.
    [The prepared statement of Mr. Obermann follows:]
    [GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
    
    Senator Carper. You bet. Thanks again for joining us. 
Thanks for those words, and thanks for what you do with your 
life, serving our Country.
    Mr. Obermann. Thank you.
    Senator Carper. We are now going to hear from Ms. Anne 
Austin, who is from Austin. I do not think we have ever had, in 
the years that I have been chairing, someone who has a name 
that just rings a bell like that. That is great.
    We are happy you are here. Please feel free to go ahead 
with your statement, and we will ask some questions once you 
are finished. Thank you. Welcome.

  STATEMENT OF ANNE AUSTIN, FORMER PRINCIPAL DEPUTY ASSISTANT 
    ADMINISTRATOR FOR THE OFFICE OF AIR AND RADIATION, U.S. 
                ENVIRONMENTAL PROTECTION AGENCY

    Ms. Austin. Chairman Carper, Ranking Member Capito, and 
members of the committee, thank you very much for the 
opportunity to testify on the topic of air quality monitoring 
technology. It is a pleasure to be with you here today and in 
such good company with my fellow panelists.
    As you know, the U.S. has experienced dramatic progress in 
air quality in recent years, and these improvements have 
spanned Presidential Administrations and hold true for criteria 
air pollutants such as ozone and PM, greenhouse gases like CO2 
and methane, and hazardous air pollutants like formaldehyde and 
benzene.
    As envisioned by Congress and embedded in the Clean Air 
Act, this progress is built on cooperative federalism between 
the USEPA and its State, local, and tribal partners, as well as 
a backbone of high quality, regulatory-grade monitors. It is 
important to note that as our air quality has improved, and 
while the NAAQS have become more stringent, the contribution of 
air pollution from forest fires and international transport 
have grown in significance. This makes a high-quality 
monitoring network and the ability of EPA and its State and 
local partners to provide regulatory relief through Clean Air 
Act tools like exceptional events even more important.
    Consequently, nonattainment designations for areas that 
cannot meaningfully address the background, fire-related, or 
international contributions will not address the remaining air 
quality issues in our Country, and this raises the important 
issue of the current State of technology with respect to air 
monitors and sensors and where low-cost, portable air sensors 
fit into the picture.
    As you know, EPA, State, local, and tribal partners have 
long relied on a robust monitoring network which complies with 
quality control and quality assurance measures and data quality 
specifications that conform to Federal reference methods and 
Federal equivalent methods used for regulatory purposes. These 
monitors are subject to Federal regulations, and in short, they 
are carefully tested, very carefully calibrated, and carefully 
maintained because of the important role the data generated 
from the monitoring networks plays in the regulatory 
decisionmaking at the local, State, tribal, and Federal levels.
    The appeal of low-cost air sensors is readily 
understandable, as they are widely accessible to individuals, 
as well as interested parties. They are good tools with which 
to explore one's local environment and to learn more about air 
quality and perhaps may even have a role to play with respect 
to identifying local air quality issues that merit further 
monitoring and analysis by a regulatory agency.
    However, and among other things, the personal air sensors 
lack quality control and quality assurance measures. They have 
not been subjected to the same rigorous FRM, Federal Reference 
Method, and FEM, Federal Equivalent Methods, testing and 
analysis, and they may have high levels of variability between 
the different instruments.
    In short, they are certainly an air quality tool, and they 
have their place in that toolbox, but the technology has not 
yet been subjected to the same level of rigorous testing and 
analysis that the existing monitoring network has stood up to 
for years, albeit with its own shortcomings. Therefore, low-
cost sensors may not quite be ready for prime time when it 
comes to being fully incorporated into the Clean Air Act 
required network utilized for agency regulatory, permitting 
attainment, and enforcement decisions.
    Instead, it would be worthwhile to refocus our attention, 
energy, and resources to Clean Air Act programs focused on the 
most pressing air quality issues grounded in cooperative 
federalism and focused on a robust, high-quality regulatory 
monitoring network. For one, how Federal funds are directed via 
intergovernmental organizations and State and local and tribal 
agencies. All of those organizations have raised longstanding 
concerns about the relative lack of resources for building and 
maintaining that robust monitoring network for criteria and 
hazardous air pollutants.
    Furthermore, EPA has repeatedly proposed to shift Federal 
resources for PM 2.5 monitoring to a different part of the 
Clean Air Act, which would limit Federal funds, require a 40 
percent cost share for States, and potentially divert State and 
local resources from other priorities. Fortunately, these 
proposed shifts have yet to be implemented.
    Third, you have also seen the reduction of key State, 
local, and tribal experts on EPA air quality programs and with 
respect to the science advisory boards. This should also be 
reversed to ensure that the proper perspective and leveraged 
expertise is provided when these decisions are being made at 
EPA.
    Fourth, there is a significant need to address 
comparability issues between FRM and FEM standards to mitigate 
challenges for future PM NAAQS attainment designations. Fifth, 
as Ranking Member Capito highlighted, there is a clear and 
present need to address positive biases identified in the EPA's 
air quality system. This is critical, given the recently 
updated PM 2.5 primary standards and the tight timeline under 
which States much provide initial area designations and 
subsequently craft State implementation plans.
    In conclusion, while personal air sensors can be useful 
tools to better understand our air quality, and they may be 
useful indicators, they are not dispositive. The existing air 
monitoring network which we rely upon for regulatory 
decisionmaking deserves our far greater focus, energy, and 
resources now and in the future.
    Thank you for the opportunity to provide testimony, and I 
stand by for your questions.
    [The prepared statement of Ms. Austin follows:]

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    Senator Carper. Thanks very much.
    I am going to telegraph my pitch. I am going to give you an 
idea of what I am going to ask next, but first, I am going to 
ask a question about FRM and FEM standards.
    Before I do that, one of the things we try to do in this 
committee is look for consensus. Sometimes, it is not that hard 
to find. Other times, it is pretty hard and we have to work at 
it especially diligently.
    The question I am going to ask you after I ask you to talk 
to us about it, FRM and FEM standards, the question I am going 
to ask you is where do you think there is agreement among the 
three of you? Where do you think there is agreement among the 
three of you and the relevant issues before us? Where do you 
think there is disagreement, and how might we reduce that 
disagreement?
    First of all, Ms. Austin, FRM and FEM standards, not 
everybody knows what we are talking about. Just give us a quick 
primer.
    Ms. Austin. I would be happy to. Thank you for the 
question, Senator Carper.
    FRM standards, the Federal Reference Method, is considered 
the gold standard by EPA as it relates to monitoring networks. 
Very rigorous testing and analysis is required for that label 
to be attached to a monitor. FEM is an equivalent method that 
EPA can also designate to monitoring technology when new ones 
come online and as technology continues to innovate.
    Then, you have the more recent advent of the low-cost air 
sensors, which are not subject to those two types of federally 
recognized and required methods of analysis and data 
collection.
    The FRMs and FEMs are standardized. The low-cost air 
sensors are not at that place yet, and quite frankly, 
understandably so. I think one thing that everybody on the 
panel could agree on is that technology innovation within this 
space is a good thing. We want to continue to innovate.
    The better data, better technology that is at a lower cost 
is good for the public. It is good for the U.S. taxpayer. At 
the same time, rushing lower cost technology for the cost of 
something new does not necessarily put us in the right position 
from a regulatory standpoint to ensure that we have maintained 
that public trust and confidence that, when regulatory 
decisions are made, it is on correct data that is going to be 
durable.
    I hope that helps.
    Senator Carper. It does.
    Let me ask you the same question, just for your thoughts on 
this, Mr. Obermann, and then Mr. Hammad.
    Mr. Obermann. Sure, thank you, Mr. Chairman.
    I believe Ms. Austin is correct. We do have a problem with 
our air monitoring network, the regulatory monitoring network. 
It is in need of attention.
    Our State programs maintaining these pieces of equipment, 
some of them decades old, there is need for funding there and 
attention, no doubt about it. We are on those monitoring 
locations co-locating our air sensors to ensure that our 
sensors are reading correctly. I see that equipment a lot in 
the field.
    The need for those programs to be fully funded, especially 
as we are now in Denver and other cities looking very carefully 
at the new annual PM 2.5 standards, those regulatory monitors 
will be depended on more than ever. I think there is some 
consensus there.
    Are there other questions I can answer for you there?
    Senator Carper. No, that is good. Thank you.
    Mr. Hammad, same issue. Anything you would like to add or 
take away?
    Mr. Hammad. I will just say, according to EPA, the Federal 
reference methods are designed to provide the most 
fundamentally sound and scientifically defensible concentration 
measurements, so they serve as the basis of comparison upon 
which to judge all other measurements.
    The FEMs are intended to use innovation and innovative 
technology to provide comparable levels of monitoring as FRMs. 
FRMs and FEMs will differ from low-cost air sensors because 
they will undergo technical and administrative reviews. A lot 
of quality assurance is going to go into them; a lot of testing 
is going to go into them.
    Low-cost air sensors, there are no standard methods for 
testing, data collecting, or siting. They provide data that is 
non-uniform, non-standardized. Again, depending on who is using 
it and for what the data is being used, they could provide 
insights into further information that might be needed.
    However, we do not differ in terms of what the FRMs and 
FEMs are meant to do and their use and benefits, and we can 
agree all on that.
    Senator Carper. How would you explain that to your 
grandmother if she was on this panel, sitting up here with us? 
Seriously, how would you explain it to your grandmother? Is 
your grandmother still alive?
    Mr. Hammad. They passed away.
    Senator Carper. Well, that is too bad. They are listening.
    Mr. Hammad. If I was going to explain it to my 
grandmothers, I would tell them that there is, for regulatory 
purposes, the government is going to use for their monitoring 
monitors that they have checked, double-checked, and triple-
checked, assess the network, assess how they are laid out, 
assess how they collect the information. They co-locate 
monitors to make sure that they are operating the way they are 
supposed to operate. They make sure that the data they are 
getting from these are useful and accurate to a degree where, 
if there is something off, they can assess what is off and 
correct it, as well.
    They have important uses and purposes. They last for 
decades. The information we get from them is a very important 
and reliable source of data.
    Low-cost air sensors, like other emerging technologies, my 
grandmothers saw the advent of cell phones, and they saw how 
they came to be, but like all technology, with the advancements 
in micro processing and the miniaturization of data and 
technology, these low-cost air sensors have become smarter. 
They have become better tools to do what they are meant to do.
    Senator Carper. All right. Well, I am sure that your 
grandmothers are looking down and saying, that is our boy. 
Thank you for that response.
    Now, Senator Capito.
    Senator Capito. Thank you. My first question was going to 
be to Mr. Hammad, but I think you have already answered it, and 
that is the difference in the technology and quality. I think 
we have established that, on the Federal reference monitors, 
and then the portable low-cost. I think we pretty much 
understand what that is. It is a licensing thing; it is an 
accuracy thing.
    I brought up, Ms. Austin, in my comments about the 
Teledyne. I am a bit confused, because everybody is saying that 
these low-cost air monitors are not being used in a regulatory 
environment. I have a map here that shows the regulatory 
monitors and then, in the blue, it has the Teledyne monitors, 
which are meant to augment, I think, what is going on with the 
regulatory monitors.
    Are you telling me that these blue dots do not really have 
any effect in terms of finding data for regulatory purposes?
    Ms. Austin. My understanding is that they do, in fact, have 
and have been used for regulatory purposes. As I am sure you 
all know, the EPA recently proposed an update for the PM 2.5 
data from T640 and T640-X PMS monitors manufactured by 
Teledyne, and have proposed to actually retroactively apply the 
network data alignment equation to all of the hourly, unaligned 
monitors in EPA's air quality system.
    Senator Capito. Let me just stop you there.
    Ms. Austin. Sorry. Yes, it is a lot.
    Senator Capito. Thinking about the grandmothers, and I am 
thinking, what that is saying is what I think I said in my 
opening statement, is that they have to recalibrate their data 
because it was inaccurate.
    Ms. Austin. Yes. That is correct, going back to 2017. The 
reason why that is so important is because, as you are looking 
at a NAAQS designation and whether or not an area falls in or 
out of attainment or stays in attainment is critical to States.
    Senator Capito. Okay.
    Ms. Austin. The reason for that being, and if you do not 
mind, I will use the State of West Virginia as an example. As I 
understand it, you have some monitors that are showing that you 
have 9.1, 9.2 micrograms per cubic meter of PM concentration in 
different parts of the State.
    Well, if those monitors are Teledyne monitors and are one 
of the two models that have been used and need to have that 
information retroactively corrected for the high positive 
biases that have been recorded over the past six to 7 years, 
that could make the difference, potentially, whether or not 
those areas fall into nonattainment or are considered 
attainment areas. That has subsequent regulatory and economic 
repercussions that could be rather significant.
    Senator Capito. Right, right. Okay, so that is the point, 
is, and thank you for that clarification.
    This concerns me, because as we see this NAAQS or the PM 
2.5 moving down, those that are on the edge or close to the 
edge, it is going to have a big impact if there was inaccurate 
data. They will be correcting that. I think it does go to, it 
is going to impact regulatory. I do not think we can say that 
these low-cost monitors are impacting any regulatory data. Is 
that a true statement?
    Ms. Austin. Yes, I would say that they certainly inform. 
EPA would not go through the process of seeking to correct the 
data inaccuracies, which I think they do a very solid job 
laying out the rationale for making that correction.
    Senator Capito. Right, thank you.
    Mr. Obermann, what is the Denver, what is your particulate 
matter? Where are you measuring right now?
    Mr. Obermann. Where are we measuring in our concentrations 
of PM 2.5?
    Senator Capito. Yes.
    Mr. Obermann. We are just below that 9 micrograms per, it 
depends on what years you are looking at.
    Senator Capito. So, 8.9, or 8.5, or are you way below?
    Mr. Obermann. No, we are, I would say, in between 8.5 and 
9.
    Senator Capito. Okay. What impacts is that going to have on 
Denver's ability to do new projects, economic development, 
manufacturing? Is this going to have some impacts on that as 
that moves down and you are close to the nonattainment area?
    Mr. Obermann. There will certainly be much planning in 
process if we actually become nonattainment for PM 2.5. We do 
not have that clearly stated yet, that is not a formal 
declaration that has been made for the Denver area. It could be 
multiple counties. It depends on which counties would become 
non-attainment, potentially, for PM 2.5.
    Would there be impacts to business in, say, Denver County 
if that happened? Yes. Yes, absolutely. There would be control 
technologies, most likely, that would be implemented at certain 
types of facilities that are high emitters of PM 2.5, and we 
would go through an extensive regulatory process at the State 
level, which we do today, it is why I know so much about it, 
with ozone, to bring reductions down, not only from industry, 
but also transportation from even other practices that generate 
air pollution that are not just at an industry.
    Senator Capito. There are, agriculture, yes. Right, yes. 
Yes, I think that is a good point. This will have a lot of 
impacts on economic development, so we have to get accurate 
data, certainly at the minimum, accurate data.
    When you were talking about your citizens' use of the 
index, I was thinking back to maybe 6 months ago when we had 
the Canadian wildfires. I was following every day what the 
index is on this, so I really see what the public health 
implications are to be able to access that.
    I just pulled up the Weather Channel, actually, when we 
were talking, to see if they have it still on there since we 
are not in a crisis kind of thing. It is all right there, so 
you can see it.
    Would those measurements be on a regulatory measure, or are 
those on low-cost measurers, or do we know?
    Mr. Obermann. Yes, I appreciate that question. The air 
quality index that you are viewing through your smartphone, 
while I do not know exactly which one or app you are using, is 
most likely based on the regulatory monitoring network, the 
FEM-FRM network.
    Senator Capito. It is? Yes.
    Mr. Obermann. Love My Air, for example, in that city 
program, we do not push air quality alerts out to smartphone 
apps or anything like that.
    Senator Capito. You do not?
    Mr. Obermann. We do have our own AQI, Air Quality Index, 
generated for our school program, where when you walk in the 
school building, it is the conditions outside of the school 
that has an air sensor on it. Those students, that community, 
does see our AQI calculation, which is based on EPA's, but the 
mass communication of AQI and air quality alerts in Denver is 
all handled by the State, and that is based on their reference 
network.
    Senator Capito. Yes, Okay. All right. Thank you.
    Senator Carper. You bet. We have been joined, as I am sure 
you noticed, by a couple of Senators who thought a lot about 
these issues and have been very much involved with them, 
particular Senator Markey. I will recognize you, and then 
Senator Padilla. Welcome. Thanks for joining us.
    Senator Markey. Yes, thank you so much, Mr. Chairman. We 
are well into a new information era, but our air quality 
monitoring systems can be seen to be stuck in the stone age. 
Black, brown, low-income communities that live in the shadow of 
air pollution deserve better. They deserve to know what they 
are breathing, and they deserve to have regulators do something 
about it.
    To tackle this problem, I introduced the Technology 
Assessment for Air Quality Management Act, cosponsored by 11 of 
my Senate colleagues, which would report on air quality 
monitors and sensors that provide a holistic understanding of 
local air pollutant measurements. It would also support 
additional staff at the Environmental Protection Agency who 
would provide accessible information advice and resources to 
communities about how to use air quality tools and, 
importantly, the data which they produce.
    Mr. Obermann, do you agree that low-cost, local air quality 
sensors can complement regulatory monitors, finding pollution 
in fence line communities that these monitors might miss?
    Mr. Obermann. Absolutely.
    Senator Markey. Mr. Obermann, can this information be used 
to spur action that addresses air pollution in fence line 
communities and other pollution-burdened communities?
    Mr. Obermann. Yes.
    Senator Markey. Thank you. That information could support 
decisions to issue alerts to wear an N-95 mask, to use mass 
transit, to halt outdoor activities, all across the board. It 
could be used for that purpose, sir?
    Mr. Obermann. Yes, I think it could be used for that 
purpose if we had more clarification and understanding with EPA 
on how to use that data for mass air quality alerts through the 
State's existing system.
    Senator Markey. Yes. I would welcome my colleagues' support 
for my legislation to provide more access to and information on 
these important technologies. Just getting the information then 
requires a response to it, but we first have to have the 
information.
    As the author of the Environmental Justice Air Quality 
Monitoring Act, last Congress, I fought for the inclusion of 
funding for air quality monitors and sensors in the Inflation 
Reduction Act, including $3 million just for low-income and 
disadvantaged communities. That funding is already being put to 
work with $2.1 million heading to Massachusetts. I thank the 
Chairman for all his work on that issue. The Mystic River 
Watershed Association received $500,000 for a new network of 
air quality monitors in Charlestown, East Boston, Everett, and 
my hometown of Malden.
    I grew up breathing dirty air. I lived in an environmental 
sacrifice ward in Malden, Massachusetts, where there was just a 
big black cloud. The Malden River was completely polluted. The 
Malden River was three blocks from my house. My mother used to 
say, Eddie, whatever you do, do not swim in the Malden River, 
because it was kind of black with a pre-Jimi Hendrix purple 
haze over it. When your mother says do not swim in the Malden 
River, you know that you are not growing up on the Mississippi 
like Tom Sawyer.
    Senator Carper. Did you say purple haze?
    Senator Markey. Purple haze.
    Senator Carper. Thank you.
    Senator Markey. Thank you so much, and thank you for maybe 
actually being one of the only people who remember that great 
song, long ago and far away.
    Mr. Obermann, in your experience, with Denver's Love My Air 
Program, was it important to have outcomes for communities 
beyond just a collection of data?
    Mr. Obermann. Yes. I would say, in the future, we are 
looking at how this data can be used for more outcomes than 
just public health education and awareness, which is how we are 
using it today. A big reason we are only using it at that level 
today is, one, the sensor technology is not robust enough to 
bring it into a regulatory context, but that technology is 
improving. We are about to buy six high-quality monitors. They 
have come down in price dramatically.
    They are FEM monitors, so they are that higher-grade of 
monitoring technology. Here we are in this city, able to buy 
them and deploy them. As we deploy those pieces of equipment at 
health clinics in front-line communities, we will absolutely be 
looking for how can this data be used in the policy and 
regulatory space.
    Senator Markey. Thank you. Thank you, Mr. Obermann.
    Thank you, Mr. Chairman. Thank you.
    Senator Carper. Thank you. Thanks for all of your work in 
these fields.
    Before I turn to our next questions from Senator Padilla, I 
am going to ask unanimous consent to enter into the record 
materials on the differences between sensors and regulatory air 
quality monitors. Is there objection? Hearing none, so ordered.
    [The referenced information follows:]
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    Senator Carper. Senator Padilla, how are you doing? Good 
morning.
    Senator Padilla. I am doing well, Mr. Chairman.
    Senator Carper. Welcome. Good to see you.
    Senator Padilla. Thank you. Thank you for organizing this 
hearing today and the opportunity to discuss the air quality 
monitoring technology, something that the State of California 
has more than 50 years of experience with. We have maintained 
one of the most extensive air monitoring networks in the world, 
actually, not just in the Nation, but around the world, which 
allows us to track progress and identify opportunities to act 
decisively to protect public health. It is both about air 
quality, but also about public health.
    Mr. Obermann, I want to thank you for your leadership in 
Denver. As you know and as you mentioned in your testimony, in 
California, we have a lot of experience with this, especially 
in the South Coast Air Quality Management District, the Bay 
Area Air Quality Management District, where they have worked 
diligently to deploy low-cost air monitoring sensors in 
impacted communities.
    My first question for you is, how can we best share these 
experiences and best practices across jurisdictions and 
certainly across State lines?
    Mr. Obermann. Yes, thank you for the question. We are 
sharing information between the air quality management 
districts, for example, in California frequently. They are 
definitely great partners, and there is actually an 
international conference on sensor technology starting April 
30th through May 4th. I know both the air quality management 
districts will be there presenting. They have great staff and 
stories to tell about how they have been using sensors in those 
communities, and they serve as a model, really, for the rest of 
the Country.
    We share information just between agencies on occasion, and 
we also, there are several conferences nationally where we 
present on our sensor programs to each other.
    Senator Padilla. Just to be clear, specific, and 
intentional here, the information sharing, it is not just data 
that is collected or how it may be interpreted, analyzed, acted 
upon, but also just evolving technologies and practices, 
programmatic information exchange?
    Mr. Obermann. Yes, we definitely exchange information 
around what technologies we are using, how that data is 
corrected against the regulatory monitoring network, for 
example, and how we use it in our public health and awareness 
programs.
    Senator Padilla. Great. You have spoken well and eloquently 
about the need to maintain this as a priority.
    I appreciate the Chairman's leadership and the work of, 
frankly, Democrats in Congress when we were very intentional in 
crafting the American Rescue Plan and the Inflation Reduction 
Act to include significant resources to help disadvantaged 
communities who are disproportionately impacted by poor air 
quality and tend to have less monitoring capabilities, less 
ability to obtain accurate air quality data, et cetera.
    Recent EPA awards have gone to California applicants like 
the Pala Band of Mission Indians to enhance air monitoring on 
their tribal reservation. Another recipient has been the Comite 
Civico del Valle organization to upgrade real-time air 
monitoring networks in the Salton Sea area of California. I 
think the recent influx of funding will enhance monitoring to 
other underserved communities.
    Mr. Obermann, next question for you is, what can the 
Federal Government do to make is easier for local or tribal 
jurisdictions to lessen the learning curve in implementation of 
low-cost air quality sensors?
    Mr. Obermann. Yes, thank you for that question. It is to 
provide boots-on-the-ground assistance. It is for EPA and other 
technical experts, consultants that they have oversight over, 
to be in those communities helping them not only stand up the 
sensors, and that is critically important because where is the 
sensor located, or even higher quality monitoring equipment 
that they could buy. It might not be a low-cost air sensor.
    Like I mentioned, Denver is purchasing monitors that are 
higher quality. Some of those grants could absolutely go toward 
purchasing higher quality monitors. They are not each $50,000 
anymore.
    Where do you site those? How do you power them correctly? 
How do you compile the data, and then even some assistance on 
what does that data mean for your health? There is a lot more 
assistance that EPA and the States could provide at the local 
level to show communities what this data really means, 
especially as higher quality data is collected.
    Senator Padilla. Can you speak to any specific or 
additional efforts needed to help avoid improper sensor 
selection, for example, or incorrect data interpretation so we 
can actually just make sure the program is effective, but we 
build the trust and support from communities that rely on it?
    Mr. Obermann. That is an important point. I think, with the 
EPA's first round of community air monitoring grants, while 
Denver did not receive one, I do know that there is a quality 
assurance plan that they require from those grantees, meaning 
if you are going to implement this type of sensor in this type 
of context, what is the quality assurance? What is the quality 
of the data that you are planning to collect?
    I think that is a really good requirement EPA has put in 
there to answer that question, so that we know what the quality 
is of these different sensors when they are used in these 
programs.
    Senator Padilla. Thank you very much. Keep up the good 
work.
    Thank you, Mr. Chairman. One last note, I am eagerly 
awaiting your Earth Day playlist.
    Senator Carper. One of the songs might have ``purple'' in 
it. We will see.
    I have several more questions, but I am going to yield to 
Senator Capito. Thanks very much for joining us. See you later.
    Senator Capito. Yes, thank you, Mr. Chairman. I have to 
scoot after I have asked my final question here.
    Mr. Hammad, the low-cost sensors have been known, 
obviously, we have talked about this, inaccurately high 
pollution levels while operating in high humidity or smoky or 
other less-than-ideal circumstances. Are there negative side 
effects that State agencies face with regard to risk 
communications or public trust that could result if publishing 
inadvertent high pollution levels, what kind of impacts would 
that have in terms of trust and communication?
    Mr. Hammad. Thank you, Senator. I will point out that the 
Teledyne monitors that you were pointing to earlier, those are 
regulatory monitors. They are not low-cost air sensors.
    Senator Capito. Right, Okay. Thanks for that distinction. 
They are inaccurate?
    Mr. Hammad. Those are the ones that need the corrections. 
Those are FEMs, not FRMs, but FEMs and FRMs are both combined 
regulatory monitors. FEMs use innovative technology like light 
and lasers to check optically how much particulate matter is in 
there, whereas a reference method monitor for PM would use 
something like a filter that you would send to a laboratory to 
test.
    Senator Capito. Do you happen to know, this is not the 
question I was going to ask, but now that we are on this, do 
you happen to know how that discrepancy was discovered by the 
EPA?
    Mr. Hammad. The State air agencies had been pointing to 
this since roughly 2019, 2020 to some of these discrepancies 
that they were finding, because they have co-located. Again, 
they do not have just one PM monitors or two PM monitors. 
Oftentimes, three or four air monitors are in their monitoring 
site. They will have several of them, and they will run them to 
ensure that they are getting accurate measurements.
    The FRMs are what we base, in this Country, EPA bases 
everything off of the FRMs. The FRMs do not give you real-time 
data, but they will give you sometimes 24 hour or 3 day, you 
pull it through a filter, and then you send that filter to the 
laboratory, and it will tell you how much particulate matter of 
a certain size exists. You use that to then make sure that your 
Federal equivalence method, your FEM regulatory monitor, is 
reading correctly.
    In the T640, T640-X corrections that were noted earlier, 
EPA pointed to the fact that there had been, according to 
temperature variations, humidity variations, wildfire smoke 
issues, there have been issues where, with low temperatures and 
high humidity, these monitors, the equivalent monitors, the 
FEMs, which are still regulatory, were reading abnormal data 
that wasn't correlating to the FRMs. Based on the weather data 
and all the other sensor data that is available at these 
regulatory monitoring stations, EPA is able to go in and make 
the corrections based on the location of where your monitoring 
station is.
    Senator Capito. The other data that they have. This has 
been in front of the EPA since 2019 with State monitoring 
agencies, and they are just now getting around to figuring this 
out?
    Mr. Hammad. Well, they needed to then formulate the actual 
correction equations with Teledyne to figure out, well, how do 
they adjust based on location, based on the technical expertise 
of the people who manufacture the monitors along with EPA's 
expertise. They lay it out in their technical support document 
that they published in that February 14 Federal register, but 
they had to work with Teledyne and the scientists that EPA had 
to figure out how, based on your location and how to correct 
this.
    Senator Capito. How to do it. Did they put a date on that, 
like when they would complete that?
    Mr. Hammad. The corrections, they proposed the corrections 
on February 14th. The comment period closed March 14th. They 
will finalize it; I do not know when. Once it gets finalized is 
when they will push out the correction, but they have the 
equations ready to roll out. They will work with the State 
agencies to perform those corrections.
    Senator Capito. Well, it would be very timely with this new 
regulation coming out to make sure that we are dealing with 
correct data. I think we would all agree with that.
    Thank you all very much. Thank you.
    Senator Carper. Senator Capito, thank you. Thank you very 
much.
    I understand Senator Kelly is trying to join us today, but 
hopefully he will arrive while we are all still here.
    I have a question for Mr. Obermann. The term Love My Air 
Program. I love that. That is really a cool way to label a 
program, make it alive and real. Where did that come from? 
Words actually matter, and I like the choice of those words.
    Mr. Obermann. Sure, yes, thank you for the question, 
Chairman. Our program name came from our own staff from within 
our department. We were working with our communications group 
and when through several options and came up with Love My Air. 
It is not a very exciting story, but that is really where it 
came from.
    Senator Carper. I was just thinking, maybe in our 
respective States, we could come up with something like Love My 
Senator.
    [Laughter.]
    Senator Carper. I do not know if we could get away with 
that. Probably not.
    Mr. Obermann, seriously now, the city of Denver is a pretty 
clear example of how local governments are using low cost air 
sensor data to educate the public about health and about air 
quality. My question, and I will have a followup to this as 
well, but my question is: in addition to informing students 
about whether to stay indoors or play outside, how else does 
the Love My Air Program benefit public health?
    Mr. Obermann. Yes, thank you for that question. The ways 
that Love My Air benefits public health is much more than just 
sensors displaying information in a public school or even 
emerging now into health clinics. It is not just about the 
data; it is what does that data mean for students, for the 
community, for whoever we are streaming that data to.
    We accompany our data with a lot of education, and our 
education is very group and small group focused. It is not 
broadcast to the millions of Denver residents. It is working in 
classrooms. It is doing teacher trainings. It is doing nurse 
trainings about air pollution and health.
    It is working at an individual level, and we find that is a 
really successful way to have a dialog about what this 
information means and how it is important to either their own 
personal health or the care that they administer to others, 
such as nurses. Really, our air pollution monitoring and the 
sensor network, it is an introduction to a discussion about air 
quality, and I would say we probably spend 75 percent of our 
time actually working with individuals to understand air 
pollution and health.
    Senator Carper. Good, thank you.
    Do you know if there are any other cities that are 
replicating the efforts that you all have taken in Denver with 
your Love My Air Program?
    Mr. Obermann. Yes, there are. Yes, thank you for that 
question. There are several others that are replicating our 
programs. We even licensed that name, Love My Air. There is an 
entity in Wisconsin that is implementing a Love My Air program 
in Milwaukee public schools. Some of our adjacent counties in 
Denver along Denver's front range are also replicating the Love 
My Air Program and using that same name.
    The emergence of these programs, particularly in public 
health departments, is rapid. Not only with the EPA grant 
funding to help start many of those programs, as you are all 
well aware of, but also, I will say this: our Love My Air 
Program is not EPA funded. It never has been.
    Our program was funded initially by a generous grant from 
the Bloomberg Foundation in 2018, and now, we are expanding 
into health clinics through another grant from the Kaiser 
Permanente Foundation. There is a lot of interest even from 
grant-making entities other than EPA to fund these types of 
programs from a public health standpoint.
    Senator Carper. I am going to ask you for the record, if 
you could just give us some idea of what other cities that are 
interested in replicating what you are doing in Denver, who 
might they contact and how might they contact that person or 
persons. You do not have to respond right now. You can just 
respond for the record.
    Mr. Obermann. Some of the other people in other cities that 
are replicating?
    Senator Carper. If someone wanted to reach out to you all 
in Denver.
    Mr. Obermann. Oh, that can be myself. Yes, Bill Obermann at 
the Denver Department of Public Health and Environment.
    Senator Carper. All right, that is good. I like to say find 
out what works, do more of that, right?
    I will go ahead and ask, because I think we have sort of 
asked this already, but the city of Denver is a pretty clear 
example of how local governments are using low-cost air sensor 
data to educate the public about health and air quality.
    I think you may have already addressed this, but I will ask 
it again, anyway. In addition to informing students about 
whether to stay indoors or play outdoors, is there anything 
else that the Love My Air Program does to benefit public health 
that you want to mention?
    Mr. Obermann. Love My Air is engaged in a number of policy 
contexts at the State level. I want to be clear: we do not use 
our sensor data today in any policy settings like at State air 
quality rulemakings, but I am involved there quite a bit. 
Knowing the information that comes from our sensor network, 
plus all the dialog, like I mentioned before, 75 percent of our 
time is spent in dialog with communities, hearing their 
stories, knowing those front line communities, bringing their 
stories, and bringing them to air policy convenings at the 
State is critical, and Love My Air has a big role to play 
there.
    While we do not use our data today in those policy 
settings, we certainly bring the voices of those communities 
that are experiencing that air quality.
    Senator Carper. Okay, thank you.
    Mr. Hammad, in your written testimony, I believe you 
mentioned that low-cost air sensors have been particularly 
useful for monitoring wildfire smoke in areas without 
regulatory monitors. Question, how does the Federal Government 
use low-cost sensors and their data to inform citizens about 
healthcare risks from wildfires?
    Mr. Hammad. Thank you, Chairman. Led by the United States 
Forest Service, the Interagency Wildland Fire Air Quality 
Response Program was created to address risks posed by wildfire 
smoke. The program has a national cache of air sensors and 
other equipment and deploys technical specialists called air 
resource advisors during large smoke events.
    Air resource advisors may provide, install, and operate 
low-cost air sensors and other equipment. It is portable in 
nature. They develop smoke forecasts and share the information 
with wildfire response teams, air quality regulators, and the 
public.
    They also have, as I mentioned in my statement, they have 
air sensors that they will loan out to firefighting agencies 
upon request, as well.
    Senator Carper. Thanks.
    Beyond Denver, how are other communities and local air 
regulators using low-cost sensors to identify hotspots that 
need more resources?
    Mr. Hammad. Some local air agencies have used non-
regulatory low-cost air sensors to help direct their regulatory 
enforcement resources. They use them to locate hotspots and 
then implement targeted inspection initiatives. This can be to 
go after truck idling or to inform regulatory inspections that 
might happen less than frequently in one location or another.
    Senator Carper. All right.
    We have been joined by Senator Kelly. Senator Kelly, good 
morning. How are you doing?
    Senator Kelly. Thank you, Mr. Chairman. Sorry I am late.
    Senator Carper. No, you are right on time.
    Senator Kelly. I deferred my time to Senator Rosen, so I 
had to go to the back of the line in Armed Services.
    Thank you to all of our witnesses for being here today. I 
want to start with Mr. Obermann. Air quality, obviously, a 
pressing issue in the west, in Arizona, but really throughout 
the western United States. As I imagine has already been 
discussed, worsening wildfires, interState and international 
air emissions have also had real impacts in the State of 
Arizona, especially when it comes to particulate matter and 
ozone pollution.
    Right now, in the Phoenix metro area, we are seeing ozone 
concentrations increase even as the region's emissions of ozone 
precursors, the chemicals that contribute to ozone, are going 
down. The chemicals are going down, but ozone concentration is 
still going up. This means that a region is being pushed into a 
more serious classification of nonattainment without having a 
full understanding of what steps can be taken to bring the 
concentrations back down.
    What leaders in Arizona have been calling for is a renewed 
commitment by EPA, both at the regional and headquarters level, 
to focus on the data and science to help understand these new 
challenges. That is what I think makes this hearing important 
today.
    Mr. Obermann, I know that the Denver region is also in 
nonattainment for ozone pollution. Can you speak to some of the 
regional issues like wildfires in western States, like Arizona 
and Colorado, and how this makes air quality attainment more 
challenging and why?
    Mr. Obermann. Sure, thank you for that question, Senator 
Kelly. Wildfires are a persistent and major impact to air 
quality. We have experienced that in Denver, much like other 
western cities.
    With the new PM 2.5 annual standard, I think the pressing 
need to understand how wildfires qualify as exceptional events 
will be very important. Whether it is called an exceptional 
event though, for nonattainment area planning and conformity 
with the Clean Air Act, it is still a public health issue. 
Wildfires are really, I believe, one of the principal reasons 
we are here today talking about air sensors, because the public 
is more aware of air quality through the wildfires we have 
experienced and through the response of the sensor network than 
ever before.
    The need for understanding how that data can be relayed to 
people and relayed timely and accurately is more important than 
ever. The nonattainment issues around ozone that we have had in 
Denver since the early 1990's, we agree that much of that 
pollution is also transported. It is not due specifically to 
wildfires, since we know that wildfires are really emitting 
precursor emissions to ozone, as you mentioned, but ozone is 
transported, certainly, from States upwind of ours.
    The more research we do in ozone pollution, the more we 
find that that transport, we have little control over, so what 
kind of things can we do on the ground that would actually 
reduce emissions that admit the precursor pollutants of ozone. 
We are working very hard on that in the Denver region. We will 
continue doing so through the next decade.
    Senator Kelly. How many of these low-cost sensors do you 
have deployed?
    Mr. Obermann. We have them deployed in 33 schools, Denver 
public schools, and several others just really for reference, 
network, and QA-QC, Quality Assurance/Quality Control.
    Senator Kelly. They give you both ozone concentration and 
precursor chemicals?
    Mr. Obermann. No, they only read PM 2.5, particulate matter 
2.5. They do not read ozone, and they do not read other, what 
we would call precursor pollutants, like NO2 to ozone.
    Senator Kelly. Is that because they are, are there sensors 
available that do?
    Mr. Obermann. Yes. The reason we use PM 2.5 is partly the 
age of our program. At the time our program was implemented, PM 
2.5 sensors were some of the best technology on the market, the 
most reliable technology. We can correct it against the 
reference monitoring network that is operated by the State.
    It is not to say that we wouldn't monitor ozone in the 
future or emissions, pollutants like nitrogen dioxide. We 
could, and we actually will be in those higher quality 
monitoring stations that we are going to be buying this year 
and next.
    Senator Kelly. What would an ideal system look like of 
monitoring? What would you want if you could get all the data? 
How many would you deploy in a city the size of Denver?
    Mr. Obermann. Yes, thank you for that question. The ideal 
monitoring system we would deploy would monitor multiple 
pollutants at the same time, and that is what we are 
purchasing. Much of the air sensor technology available today 
really monitors one or two pollutants. That is what makes it 
more affordable.
    The city can purchase multiple monitors that they put in 
one box, and we can purchase up to 10 of those over the next 
several years and disperse them throughout the city. In a city 
the size of Denver, about 10 is a good number, and that is 
partly because some of these pollutants we monitor do not vary 
tremendously location by location. PM 2.5 does not vary 
tremendously location by location.
    Ozone is a regional pollutant, so there is not really a 
need to monitor that on every block. There are other pollutants 
like black carbon, nitrogen dioxide, certainly other pollutants 
that we can monitor today that do vary tremendously location to 
location.
    Senator Kelly. When a pollutant like nitrogen dioxide or 
black carbon varies location to location, can you then infer 
some kind of vector from it, and say, well, since we have this 
variation, we can say that it is coming from a certain 
location, or at least a direction?
    Mr. Obermann. We, today, do not look at our data at that 
short of a time period. We look at trends over, say, the last 
month or the last year. Do we see hotspots in our network, even 
our PM 2.5 sensor network, when we look at a day-to-day? Yes, 
but I wouldn't say that there are persistent hotspots that we 
see from our PM 2.5 network today.
    We do not know if we are going to see that when we start to 
implement our NO2 monitoring that I mentioned we are going to 
be purchasing in the future here. The answer is, we do not 
really know yet if we would see a lot of variation in those 
pollutants, but we are going to find out.
    Senator Kelly. Thank you, and Mr. Chairman, can I have a 
few more minutes, or are you ready to wrap it up?
    Senator Carper. I am ready to hear more from you. Go right 
ahead.
    Senator Kelly. Ms. Austin, I appreciate the comments in 
your testimony about how the EPA and the need to invest in more 
resources to help regions track regulated pollutants. I think 
another important aspect of this issue is developing region-
specific models to help air quality officials understand what 
needs to be done to improve air quality.
    Can you expand a bit on what kind of costs are involved in 
developing these regional airshed models, and can you explain 
why modeling for ozone pollution is challenging?
    Ms. Austin. I would be happy to get back to you on the cost 
related to regional airshed modeling. I do not have that 
information before me now, but I would be happy to get it to 
you after the hearing.
    I would say that some of the general challenges related to 
regional air modeling and the State of Arizona's, State of 
Colorado, most western States, for something like ozone, do 
present unique challenges, given the seasons in which ozone are 
traditionally higher. Your topography and geography can play 
significant roles in how that modeling is done and how it is 
captured, and ultimately, how that is reflected in the data.
    An ozone challenge in the eastern part of the United 
States, say, down in the Carolinas or even Virginia, which is 
right next door, will present probably very differently than it 
would out in the west. Those are important considerations for 
EPA to be able to take into consideration when it is 
promulgating policy, when it is recommending changes, when it 
is reviewing State implementation plans.
    I definitely think that those are the types of issues that 
EPA endeavors to in a way accordingly and appropriately and 
consider recognizing that a one-size-fits-all approach, 
especially with something like ozone, is not appropriate, just 
given the chemistry.
    Senator Kelly. Thank you. Thank you, Mr. Chairman.
    Senator Carper. You are quite welcome. Thank you for 
joining us.
    I have a question for Ms. Austin, but I am going to delay 
it until we have heard from Senator Sullivan. Welcome. Good to 
see you.
    Senator Sullivan. Thank you, Mr. Chairman.
    Senator Carper. You bet.
    Senator Sullivan. I want to thank the witnesses. I 
appreciate your focus on this important issue.
    I wanted to kind of get to the PM 2.5, particulate matter, 
issue. We have a real challenge in the interior part of Alaska. 
We have a nonattainment area in interior Alaska, the Fairbanks 
area.
    The challenge there is 60 to 80 percent of the pollution 
putting Fairbanks over the standard comes from wood-burning 
stoves in people's homes. We have a unique environment, winter 
environment, there. Fairbanks is kind of in a bowl, and if you 
have been to interior Alaska, it is really cold, 50 below zero 
in the winter. You have this kind of inversion challenge.
    The community has been working really hard to reduce 
emissions, really hard. The EPA in back-to-back actions in 2023 
has started to initiate sanctions against the community for its 
inability to meet the existing PM 2.5 standard and has 
concurrently proposed to lower emissions.
    Then, really badly, in my view, worked with an outside 
environmental group, I think it was the Sierra Club, without 
coordinating with the State or the congressional delegation to 
get an agreement with some far-left environmental group on what 
Alaskans should do. Really bad approach from the EPA that 
myself and my congressional colleagues have written them about, 
like hey, you have to check in with the people who are in 
charge of the State.
    I would like any and all, why do not we start with you, Ms. 
Austin, to discuss how a one-size-fits-all approach to 
monitoring PM 2.5 can be very challenging but fail community-
specific needs. Like I said, the extreme winter environment, 
the use of woodstoves to address sub-zero climate conditions, 
these kind of create a real challenging situation where, in 
Alaska, a lot of times, one-size-fits-all approaches from D.C. 
just do not work. They do not fit, and we end up spending an 
enormous amount of time trying to address that.
    Do you have any thoughts? I will just go to each of the 
witnesses. It is really my only big question, but it is a 
really important one. This is just a specific example where we 
have been putting an enormous amount of work and effort into 
trying to reduce these emissions. We understand the importance 
of doing that, and yet, the unique elements of what goes on in 
Alaska, particularly in the winter, make it a challenge.
    Ms. Austin. Senator Sullivan, thank you very much for the 
question. I think your characterization of a one-size approach 
fits all is unfortunately but understandably, to some degree. 
EPA is there to set national standards, but you look back to 
the Clean Air Act, which has that cooperative federalism 
approach deliberately embedded in it.
    Senator Sullivan. A lot of times, EPA forgets about that 
cooperative federalism approach, right, where the States are in 
the lead. A lot of people do not know that that is the law.
    Ms. Austin. What I would say to that is, I think one area 
where EPA has striven to really do more and should continue to 
do and probably up the ante a bit is engage with States. 
Engage, engage, engage.
    Senator Sullivan. When they like, with a national 
environmental group, and do a consent decree without bringing 
the State of Alaska or the congressional delegation in, you 
would call that a foul in terms of engaging with the States?
    Ms. Austin. I would posit that that is not the way to move 
forward and actually find a path forward to environmental 
improvement to benefit public health.
    Senator Sullivan. Yes, I agree with that. Thank you.
    Mr. Obermann, do you have a view on this, in general?
    Mr. Obermann. Sure, thank you for the question. Yes, I am 
not just familiar with the context in Alaska, but I can say PM 
2.5 pollution due to wood-burning stoves is an issue in Denver, 
too.
    Senator Sullivan. Yes. You guys have kind of the inversion 
thing with the mountain.
    Mr. Obermann. Yes, Salt Lake City, where I grew up, 
actually does as well.
    There are State rules, and there may be in Alaska as well, 
I am not familiar with the regulatory context there, that 
require certain types of stoves that are EPA-certified to be 
burned.
    The air pollution sensor network that we have in Denver can 
be a great complement to the public health that those 
individuals are experiencing in your community. They can look 
at their property's air pollution level and say, what does that 
mean for my health today? If I am asthmatic, or if my 
grandmother is asthmatic, what does that mean?
    Honestly, in the context from my perspective, what we hear 
is people need to know what the air pollution is in those 
communities and why they potentially feel off that day. 
Programs like ours can help people just get quicker information 
and understand what that means for their health and even have 
resources to understand more about air pollution and health, if 
say, they go to our website or other means of communication.
    Senator Sullivan. Good. Thank you.
    Mr. Hammad, do you have a view on this, given your CRS 
perch?
    Mr. Hammad. Yes, thank you, Senator Sullivan.
    First, the State of Alaska and Fairbanks in particular have 
made strides in their Change Out Program, and that is where 
they change out the wood-burning stoves, and they have 
developed the program, been leaders across the Nation in 
developing that program.
    Senator Sullivan. You know, the EPA is supposed to be 
certifying those stoves, and they have not done a very good job 
at that. I do not know what the issues in Denver are, but in 
Alaska, they have not done a good job on certifying the stoves.
    Mr. Hammad. The certification program works for the 
manufacturers and the retailers of the stoves, and Alaska 
joined the northeast States in their recent litigation action 
against EPA for their certification program. They just have 
some disagreements about the way, the method, that EPA is 
completing those certifications.
    Senator Sullivan. Would you agree that the EPA is kind of 
failing in that certification process, just from the CRS 
perspective?
    Mr. Hammad. I will say that the States feel that EPA is 
failing them. Alaska and the northeast States did file suit. 
CRS is going to give you the facts on that, and that is what we 
will give you. The States do feel that EPA needs to update 
their certification methods for that Change Out Program.
    It is the method in which the wood is burned in the oven 
that they disagree on, and the organization real-world 
applications versus a test location are not the same. That is 
where the disagreement and discord happens.
    Senator Sullivan. Good. Well, I appreciate that.
    Thank you, Mr. Chairman. I am sorry I went over time there, 
but it is an important issue particularly in interior Alaska.
    Senator Carper. It is Okay. Yes, we are glad you could join 
us.
    Senator Sullivan. Thank you.
    Senator Carper. Ms. Austin, I promise we are not going to 
forget you here. I am going to have at least one question just 
for you.
    I think you agreed that sensor technology is improving 
fairly rapidly. Do you support even more work by EPA to improve 
the integration of sensor data into EPA's work?
    Ms. Austin. Yes, I do, but with the caveat that those 
resources not be diverted from otherwise maintaining, updating, 
and correcting the reference monitor network.
    Senator Carper. Would any of our other witnesses want to 
comment as well on that issue? Anything you want to add, take 
away?
    Mr. Obermann. Yes, the air pollution monitoring 
technologies for our criteria air pollutants like Mr. Hammad 
mentioned earlier, the six criteria air pollutants, are 
actually more affordable than ever. I believe there is a path 
to help States continue their regulatory monitoring efforts, as 
well as also help local communities and governments implement 
air sensor programs on the ground. I think there is space for 
both.
    Senator Carper. Okay, thank you.
    Mr. Hammad?
    Mr. Hammad. The potential future uses of low-cost air 
sensors and where it goes from here depends, I think, on a 
range of factors, including the State of the technology, 
whether the improvements have been made and such. The leaps in 
the technology that we have seen in the last few years have 
shown that there have been a lot of advancements.
    In addition, their continued or expanded use may depend on 
any changes in EPA assessment regarding their capabilities and 
whether EPA can determine certain devices would meet any 
regulatory standards for monitoring. I think that would change 
the landscape for low-cost air sensors and where they go from 
here.
    Senator Carper. Okay, thank you. I have another question, 
Mr. Hammad, for you. It is one that deals with funding from 
Congress.
    As you know, Congress has provided funding for EPA to 
administer community air quality monitoring grants through the 
American Rescue Plan and through the Inflation Reduction Act. 
In November of, I think it was 2022, EPA selected over 100, 
maybe a 130-some air monitoring projects across some 37 States 
to receive this funding.
    My question is, in your testimony, you discuss how low-cost 
air sensor projects that have received funding or will receive 
Federal funding, how can federally funded sensor projects 
ensure a high quality of data? I will say that again: how can 
federally funded sensor projects ensure a high quality of data?
    If you would, just please elaborate on the process for 
projects to undergo quality assurance. In your answers, just, 
if you would, please also describe the type of entities that 
received this funding and for what types of projects.
    Mr. Hammad. Thank you, Chairman Carper. According to GOA, 
there are 132 community air projects that will be conducted by 
groups including nonprofits, States, local air agencies, 
tribes, and more than half these projects plan to use sensors. 
I included that in my testimony, and the funding recipients 
conducting low-cost air sensor data collection would be 
required to submit a quality assurance project plan. EPA refers 
to these as QAPPs, quality assurance project plan.
    Senator Carper. As what?
    Mr. Hammad. QAPPS.
    Senator Carper. What does that stand for?
    Mr. Hammad. Quality assurance project plan, QAPP.
    Senator Carper. Thank you. An acronym for everything.
    Mr. Hammad. That is the government.
    Senator Carper. Thank you.
    Mr. Hammad. Per the requirements of the CFR, the quality 
assurance project plan is a written document that provides a 
blueprint for the entire project and each specific task to 
ensure that the project produces reliable data that can be used 
to meet the project's overall objectives and goals. It provides 
the who, what, when, where, why, and how of the project, and 
according to EPA, a quality assurance project plan, a QAPP, 
aims to ensure the credibility of information collected or used 
by the community air project itself.
    Senator Carper. Okay. Thank you.
    I have a question, one more question, that I think I will 
ask for all of you to respond to, if you would. Ms. Austin, if 
we could just start with you.
    The question is, in closing, would each of you take a 
moment or two and tell us where you see common ground with your 
fellow witnesses? If the answer is that we are farther apart 
than we started, that would be too bad, but I hope you can 
identify maybe some areas where you already had some common 
ground and now it is maybe more or less, but just be really 
honest with us, and that will be helpful.
    If you could go first?
    Ms. Austin. Chairman Carper, thank you. I certainly see 
common ground where technology innovation is going to further 
reduce costs. Data quality will improve with respect to air 
sensors. I think that is a very exciting place to, frankly, be 
as a Country. We have seen it in various other technology 
applications that affect us and make our lives easier in 
everyday life. I think air sensors are certainly on that train 
and it is moving in the right direction.
    I think we can also agree that when it comes to the 
reference and regulatory monitors, that more need to be done 
and that those should continue to serve as the backbone for any 
regulatory decisionmaking at State air agencies and at the 
Federal level.
    Perhaps 1 day, the air sensors will catch up, they will get 
to a level where they are equally robust. I look forward to 
that day. I hope it gets there, but alas, I do not think today 
is that day. I think there is a lot to look forward to in both 
contexts.
    Senator Carper. Good. Thank you. I like that note of 
optimism. Thanks so much.
    Mr. Obermann, please, same question, common ground.
    Mr. Obermann. Thank you for the question, Mr. Chairman.
    I agree that our reference air quality monitoring network 
run by the EPA and the States needs a lot of support and help. 
It needs to innovate over time as these new technologies become 
available that are reference quality.
    We know of several vendors in Colorado that have gotten 
that stamp of approval from EPA to use their monitors as 
reference-level monitors, and that is the same process that 
other makers like Teledyne have used for a long time. We know 
that there is a need, and I agree to support that monitoring 
network.
    The reality is there are many, many areas in our Country 
where we will never be able to cover it with a regulatory-grade 
monitoring network. The sensors that are available on the 
market today help fill in those voids, and there are some big 
voids out there, especially in areas where they are prone to 
wildfires.
    I think an area where we can agree is that that sensor 
network can absolutely help inform where some of our air 
pollution challenge is changing. If in some of our more rural 
communities, air pollution is actually increasing due to things 
like wildfires, we can know that through the air sensor network 
so that perhaps we can bring regulatory air monitoring there in 
the future.
    I believe there is a lot of agreement here on the panel 
about sensors broadening that awareness and perhaps for 
attention with regulatory air monitoring in the future.
    Senator Carper. Mr. Hammad?
    Mr. Hammad. Thank you, Chairman Carper.
    I think we do agree on the current State of our regulatory 
monitors and their importance and the information that they 
have been able to provide the Country for the past few decades 
has been invaluable.
    Where low-cost air sensors are and how they fill these data 
gaps and help identify opportunities for regulatory agencies to 
direct their resources, I think we also agree on that.
    Where the technology goes from now, again, depends on the 
level of investments and the capacity for EPA to review and 
continue to review these technologies and to provide further 
guidance on their use and the data collection and the handling 
and proper siting of them. Like my co-panelists, I think I 
agree in saying, you know, hopefully 1 day they do reach the 
capacity to be used in a regulatory purpose.
    Senator Carper. Okay. Thank you.
    I think we are going to close here. We had one or two other 
colleagues that are trying to get here, but there are a bunch 
of committees that are meeting at the same time, and it is, we 
got a pretty good bipartisan cross-section that was able to be 
here. I had hoped that we might get one or two more, but I do 
not think we are.
    I am going to go ahead and begin to close this.
    I just want to thank you all for coming today and for the 
time you put into actually coming here in person and really for 
the work you do with your lives and what you do for your own 
communities and for your States and our Country and our planet. 
We thank you for that.
    I want to thank members of our staff for the very good work 
that they do week after week after week. I have always 
surrounded myself with people smarter than me. My wife says it 
is not hard to find them. We have some smart cookies behind me.
    The other thing that we have going for us is they sort of 
like each other and they work well together. You all heard of 
something called ``trickle-down theory.'' I believe in that. I 
think Senator Capito does, as well. We, for the most part, I 
think, work really well together, and I think that is a 
positive influence on the members of our staff.
    I want to maybe mention one or two other things, but I 
think that we can all pretty much agree that folks in this day 
and age should not have to worry about whether the air that 
they breathe is safe for them and for their families, whether 
young or old, yet far too many communities are exposed to 
harmful air pollution, even despite all of our efforts to 
reduce those threats.
    Fortunately, as we have learned today, the advancements in 
low-cost air quality sensors equip a lot of communities with 
knowledge about their air quality, and this knowledge is 
helping local policymakers make evidence-based decisions in 
order to improve public health further.
    Before we adjourn, I am going to ask unanimous consent to 
submit for the record materials relating to today's hearing. 
This is my favorite part of the hearing, when I get to ask, 
make a unanimous consent request, and there is no one here to 
object, no other Senators. Hearing no objection, I am going to 
move on to some housekeeping.

    [The referenced information follows:]

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    Senator Carper. Senators will be allowed to submit written 
questions for the record through the close of business on 
Wednesday, April 24th. We will compile those questions. We are 
going to send them to our witnesses, and we are going to ask 
you all to reply, if you would, by Wednesday, May the 8th.
    With that, I think we will just declare this hearing 
adjourned. Thanks so much.
    [Whereupon, at 11:48 a.m., the hearing was adjourned.]
  

                          [all]