EPA Update/Discussion on the National Monitoring Strategy, and Other National Monitoring IssuesTim Hanley - EPA OAQPS

WESTAR - Continuous PM2.5 Monitoring WorkshopApril 13th, 2005Portland, Oregon

Agenda

Background National Ambient Air Monitoring Strategy Development Strategy Components

NCore Level II Technology Regulatory Changes Communications and Outreach

Implementation Plan Summary Monitoring Regulation Proposal Package Resource Support for NMS Implementation Technology Transfer and Training

PM coarse (PM10 - PM2.5) Notes Speciation Program Notes Draft PM2.5 Equivalency Criteria

Background: Major Themes and Objectives

Major Themes: Multiple pollutant measurement infrastructure to support integrated air program

management The right data to support science and policy

Public Reporting Flexibility to align resources to the most important monitoring now and in the

future Objectives:

Overall - Create a more responsive and value added network Specific: Transition to a true multiple pollutant measurement (aerosols, gases, precursors

and end products, criteria and non criteria) framework emphasizing rapid, near continuous data delivery….that supports (equally): Public Reporting - S/L/T web sites & AIRNow Review/Development of NAAQS/related health studies Accountability for CAIR and other major programs (and AQ trends) Strategy development (SIPs, CAIR+, etc.), e.g., model evaluation Compliance (e.g., NAAQS comparisons for attainment/nonattainment) Science support….(methods, atm. processes, health research) Ecosystem assessment (new)

This transition occurs from a historically layered single pollutant design emphasizing (and strongly perceived) as only serving a compliance objective.

Implications from NAS…CASAC…CAAAC

National Academy of Sciences Reports Air Quality Management in the United States

Calls for broader multi-pollutant integration Additional attention to air toxics and ecosystem/multimedia Catalyzed new CAAAC S&T and Policy subgroups

Research Priorities for Airborne Particulate Matter Advocate multi-pollutant measurement approaches

CASAC subcommittee on Monitoring Strong endorsement

CAAAC S&T subgroup.. Draft Recommendations Endorse EPA’s proposed national monitoring strategy and encourage regional monitoring

strategies. The existing monitoring networks are top-heavy on compliance and light on addressing other monitoring objectives, especially control strategy development and accountability. A redistribution of monitoring resources may be necessary.

Collective message EPA is relying on the strategy to demonstrate

commitment to change

National Ambient Air Monitoring Strategy Overview – Why?

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100%+ of NAAQS80 - 100% of NAAQS60 - 80% of NAAQS< 60% of NAAQS

National Ambient Air Monitoring Strategy Development October 2001 – 3 day workshop on National Monitoring strategy

with States, locals, Tribes and EPA. July 2002 – The National Monitoring Strategy Steering Committee

met to discuss the first draft of the monitoring strategy document prior to release for review to the public

Sept 2002 – OAQPS Office Director S. Page releases document for review OAQPS solicits comments on document through March 2003

July 2003 – CASAC technical subcommittee meets to discuss draft strategy

Nov 2003 – CASAC provides comments to Administrator April 2004 – Final Draft of NMS posted on AMTIC December 2004 - CASAC Technical Subcommittee meets to review

National Monitoring Strategy Implementation Plan

Strategy Components

National Monitoring Strategy Major Components

NCore Monitoring Network

Network Assessments

Technology Quality AssuranceMonitoring

RegulationsCommunications

and Outreach

NCore Level IResearch Sites

Ncore Level IIMulti-pollutant Sites

NCore Level III

Manual MethodsPM2.5 FRM, HNO3, NH3

Continuous Methods for:NO/NOy, SO2, CO, PM2.5, PMc

Meteorology for:T, RH, WS, WD

Working with EPA Regions, State, and local agencies on first pass at NCore Level II site recommendations:

Technology

Three major technology needs identified as part of the National Monitoring Strategy: Timely reporting of high quality, highly time-

resolved ambient monitoring data; Share all continuous O3, PM2.5, and PM10 data Share all NCore level II continuous data

CO, SO2, NO/NOy Meteorology

Collocated characterization of precursor gases CO, SO2, NO, and NOy – pilot this year Ammonia and Nitric Acid gases

Highly time-resolved, spatially rich PM2.5 data

New Procedures for Storing PM2.5 Continuous Monitoring data in AQS Objective:

Store PM2.5 continuous monitoring data in AQS in a way that data users understand comparability to the FRM; therefore, providing greater utility and use of data.

Solution: Need to delineate valid data that is FRM-like from valid data that

is significantly different from the FRM. Continue to store valid PM2.5 continuous monitoring data that is FRM-

like as “PM2.5 at local conditions” - parameter code 88101. Store valid raw data that is significantly different than the FRM as

“PM2.5 Raw Data” - parameter code 88501. Store valid data from instruments measuring “Total Atmospheric

PM2.5” as parameter code 88500. Memo explaining details is being prepared

Current and Planned Parameters for the AIRNow Data Management Center

Pollutant/Meteorological Parameter Naming Units

Ozone OZONE ppb PM2.5 mass PM2.5 g/m3PM10 mass PM10 g/m3

NO (nitric oxide) NO ppb NO2 (nitrogen dioxide) True measure NO2T ppb NOx-NO NO2 ppb NOy-NO NO2Y ppb NOx (nitrogen oxides) NOX ppb NOy (total reactive nitrogen) NOY ppb SO2 (sulphur dioxide) Conventional SO2 ppb SO2 Trace Level SO2T ppb CO (carbon monoxide) Conventional CO ppbCO Trace level COT ppb EC (elemental carbon) – PM2.5 EC g/m3 OC (organic carbon—not adjusted for O, H) – OC g/m3 BC (black carbon) BC g/m3 UVB (second channel of Aethalometer) UVB nanometeNO3 ion (nitrate-not adjusted for ammonium ion) NO3 g/m3 SO4 ion (sulfates-not adjusted for ammonium ion) SO4 g/m3 Ambient temperature TEMP ooC Wind speed WS m/s Wind direction WD degrees Relative humidity RHUM % Barometric pressure BARPR mb Solar radiation SRAD Watts/m2

Current Parameters

Precursor GasParameters

SpeciationParameters

MeteorologicalParameters

0.9 0.95 1 1.05 1.16

4

2

0

2

4

beta (the slope)

alph

a (t

he in

terc

ept)

Draft Federal Equivalent Method approval criteria for PM2.5 Continuous Monitors Data Quality Objective process that links equivalency criteria to expected data

quality in network Extensive statistical investigation with EPA – OAQPS, EPA - ORD, RTI, and Battelle. Expect to propose as applicable to both National Equivalency and Regional

Approved Methods

0.3 0.4 0.5 0.6 0.7 0.80.92

0.93

0.94

0.95

0.96

0.97

0.98

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1

Expected CorrelationApproximate Lower Bound of a 95% Confidence Interval Correlation Lower Bound

Population CV

Cor

rela

tion

Update on the development of precursor gas analyzers

Multiple companies identify having high sensitivity gas analyzers:

Thermo Environmental Instruments API Ecotech

EPA-OAQPS staff have met with all three companies - some on multiple occasions.

EPA OAQPS has a dedicated team working on precursor gas analyzers

Laboratory study is complete Field Study about to begin Testing trace gas analyzers with two

commercial data management systems ESC 8832

Also worked with 8816 Envidas

State/local/Tribal/CASTNet pilot of precursor gas analyzers this year

Mention of commercial names does not constitute endorsement by EPA

EPA - OAQPS Trace Gas Products Short written summaries of each method - have been distributed Laboratory and field study designed to determine a number of performance

characteristics - Study results are available from laboratory Developing a Technical Assistance Document (TAD) on trace gas monitoring

work assignment with Battelle building from existing knowledge and what were learning from the current

commercially available trace gas analyzers Soliciting review from 3rd party expert

SOP’s Available on AMTIC web site - www.epa.gov/ttn/amtic/precur.html applicable to each make and model our trace gas team is working with will include separate SOP(s) on data management

Data Quality Objectives scheduled for development this year

Data reporting changes necessary for receipt of data at: AQS AIRNow

National Monitoring Strategy - Regulatory Changes 1) The draft regulations to support implementation of the National Monitoring

Strategy are being recommended by staff. Ultimately, the EPA Administrator makes the final decision to actually propose any changes.

2) Describe how the monitoring regulatory changes fit into the broader National Monitoring Strategy

3) Provide information on the ambient monitoring strategy regulatory package:- What are the major themes?

- What are the major changes to the ambient monitoring program?- How was the proposal package was put together- Who has provided input?- Review and next steps?

How do the monitoring regulatory changes fit into the broader National Monitoring Strategy?

National Monitoring Strategy

Required Monitoring Activities

By Regulation

Non-regulated Activities,but provided for as part of NMS

PM2.5 Monitoring Programs PM2.5 Monitoring Programs

PM10

NCore Level II

Ozone Monitoring Programs

Criteria Gases – CO, SO2, NO2

FRM/FEM

STN

Continuous

QA - PEP

New Measurements

Supp. Spec. Sites

Continuous Speciation

IMPROVE

Air Toxics Monitoring

NATTS

Community Projects

S/L AT monitoring

Class 1 Areas

State Protocol Sites

Pb

Ozone Monitoring

PAMS

Trace gases CO, SO2, NOy

Met: Ta, WS, WD, RH

Meteorology

Ozone Precursors NCore Level 1 Research Sites

Ammonia

Nitric Acid

CASTNet

National Performance Audit Program

Blue - 103 (fully) FundedYellow – 105 (shared) FundedYellow – 105 (shared) FundedGreen – Mixed FundingPurple – Not FundedGold – Funded from S&T or EPM

What are the major themes of the Regulatory Changes?

Multiple monitoring objectives Collocation for multi-pollutant characterization Continuous monitoring Improved spatial coverage Divestment of unnecessary monitoring Clean up monitoring regulations no longer

applicable

What are the major changes to ambient monitoring regulations? First major restructuring of ambient monitoring

networks since 1970’s - Introduction of National Core Network (NCore)

Re-invention of QA program New, statistically derived equivalency criteria for

approval of PM2.5 continuous monitors Revised minimum network requirements for O3 and

PM2.5 sites based upon concentration and population of area

First major restructuring of ambient monitoring networks since 1970’s National Air Monitoring Stations (NAMS) distinction goes

away Introduction of National Core Network (NCore)

State and Local Air Monitoring Stations (SLAMS) essentially become NCore level III

Some new and many existing sites with several collocated parameters become NCore level II: PM2.5 (FRM and continuous), PM10, O3, CO, SO2, NO/NOy Meteorology: WS, WD, Ta, RH Urban and rural components at representative sites

No regulatory requirements for: NCore level I

Re-invention of QA program Emphasis on Data Quality Objective process to establish

performance based standards PM2.5 - Already exists Ozone - Newly developed

Updated QA to be consistent with EPA Order 5360.1 Quality Management Plan (QMP) Quality Assurance Project Plan (QAPP) Quality Assurance Lead for an agency

Removal of antiquated requirements on manual methods no longer being used.

Changes in gas audit concentrations lower limit of range to reflect improvements in air quality.

Change in frequency of required gas monitor precision checks to include confidence limits.

PM10 collocation requirement updated to be consistent with PM2.5 Change in statistics for assessment of precision and bias. New bias statistics for lead.

Who has provided input on the monitoring regulations? National Monitoring Strategy Steering Committee

Included national leaders in ambient monitoring and air quality management Provided initial recommendations for re-inventing monitoring program

Monitoring Rule Workgroup formed in 2001 Included EPA OAQPS, Regions, States, Locals, & Tribes Met in a workshop in the fall of 2001 and several times via conference calls

until spring of 2004. Reviewed and provided recommended changes to monitoring regulations in

detail Quality Assurance Workgroup provided re-invented QA section of

regulation Technology Workgroup led initial efforts on PM2.5 continuous

monitoring ORD/OAQPS team provided new national equivalency criteria

What’s Covered in the Proposed Changes to the Monitoring Regulations

MonitoringRegulations

Part 50NAAQS

And Reference Methods

Part 53Approval of Reference and

Equivalent Methods

Part 58Monitoring Regulations

Reductions in reportingRequirements to AQS

for sampler support data

Class III Equivalency for PM2.5 Continuous Monitors

Reporting and DataCertification,

Sample Frequency

Quality AssuranceAppendix A

MethodologyAppendix C

Network DesignAppendix D

Regional ApprovedMethods

Review and Next Steps for Proposal Package

What review has occurred on the proposal package? Spring 2004:

S/L/T/EPA - Regulatory review workgroup conference calls OAQPS/EMAD review of preamble

Summer 2004: Further developed preamble Solicited input from OAQPS policy staff Internal monitoring staff review of whole package

Fall 2004: Part 53 sections on Class III equivalency added Entire proposal package sent back out to EPA Regional Offices for final read by monitoring contacts

Winter 2004-2005 Prepared document for Federal Registrar Package sent to EPA Office of General Council for legal review

What are the next steps? Finish ICR (costing out required monitoring) Clearance from OAQPS EPA workgroup clearance Send to OMB Clearance by EPA and proposal published

Overall National Monitoring Strategy Communications and Outreach Extensive outreach over the last 3 years to variety of stakeholders through conference presentations – including the NAQC, teleconferences, and meetings.

AMTIC web site dedicated to the National Air Monitoring Strategy http://www.epa.gov/ttn/amtic/monitor.html

Two Clean Air Scientific Advisory Committee (CASAC) dedicated subcommittee public meetings July 2003 - http://www.epa.gov/sab/pdf/casacl04001.pdf December 2004 – Subcommittee response being developed

Expected to include recommendations for outreach on NCore level II sites Senior Management briefings in OAR including the Assistant Administrator last

June. NMS Flyer for distribution to the public posted last summer with hard copies to

Main City Libraries with populations over 1M; States, local, and Tribal monitoring programs; and EPA Regional Offices. http://www.epa.gov/ttn/amtic/files/ambient/monitorstrat/aqbrochure.pdf

Planning underway for future workshops and conferences Many aware of the process and generally supportive. Concerns, when raised, are

usually over the details and funding

Implementation Plan Summary Phased implementation starting now and through 2007

2005 Pilot of precursor gas monitors with States/locals/Tribes Modifications in Regulations (proposal in 2005)

Codification of NCore New criteria measurement minimums for Ozone and PM2.5

Introduction of new performance based approaches for monitor approval Regional Approved Method for continuous PM2.5 mass New national equivalency standards for PM2.5 mass Restructuring of QA….more DQO and PBMS emphasis

Resource Support for NMS Implementation Redistribution/modifications in STAG 103 PM2.5 Grants and PAMS 105 Largely, but not entirely, across measurements, not States..

Technology Transfer and Training Focusing on new technologies, QA In-house and outreach

Resource support for NMS Implementation Unused Section 103 Funds

Memo from OAQPS Director S. Page to Regional Air Division Directors to support 4 activities: PM2.5 continuous monitors Data management and telemetry equipment Precursor trace gas monitors for CO, SO2, NOy PM measurements that support ambient diesel characterization

Many NMS activities are already underway Development of 2005 Grant Guidance

Planned budget was $42.5M Maintain critical components of PM2.5 monitoring network. Investments and divestments are identified, consistent with the

National Monitoring Strategy. See section 11 - implementation plan First planned resources to support implementation of Pilot NCore level II sites

Issues: Phase shift between EPA fiscal year and availability of funds in monitoring grants Purchase of trace gas equipment if not designated as reference or equivalent

Challenges to Implementation Communications

Despite substantial outreach, many stakeholders are unaware of how the changes will affect them. Network Design Issues

Divestment of some FRM and Speciation Sites that may be locally important NCore Level II design Appropriate balance between urban and rural monitoring Integration of CASTNet

Policy tensions..(somewhat resolved) Shift toward information/science, perceived less compliance ALA raised concerns Need for support by OAR, Regions, CASAC,…

Regulations Definition of a special purpose monitor Ozone requirements may be perceived as reducing requirements in some areas

Resource Issues Costing our monitoring programs goes beyond capital acquisition and O/M

Also includes local, regional, and national data analyses; and internal and independent QA Moving STAG 103 funds from conventional monitoring to independent QA and data analysis

Reluctance to change (States and EPA) Magnified by $$$ in monitoring

Significant lag between planning and turn-key operation of new monitoring programs $$$ for Level 1 sites….serious

Outside of STAG…similar to Supersite program

PM2.5 Monitoring Network Implementation

PM2.5 FRM’s Attainment Designations final in ’05 Number of FRMs expected to decrease

FY ’03 = 1095 FY ’04 = 990 FY ’05 = 917

Speciation Program Number of Speciation sites expected to

decrease Mostly 1/6 sites FY ’03 = 286 FY ’04 = 251 FY ’05 = 227

PM2.5 continuous monitoring AQI with PM2.5 went public on AIRNow

web site - Oct 1, 2003 Number of sites expected to increase

FY ’03 = 305 FY ’04 = 451 FY ’05 = 522

0

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2003 2004 2005

FRM

Speciation

ContinuousPM

Maintaining Critical Components High Value FRM Monitoring Sites.

Speciation Trends Network.

Continuous Monitoring Network.

IMPROVE.

Performance Evaluation Program and filter procurement.

New Investments NCore level II technology investments for PM precursor gases. This includes

high sensitivity gas monitors for CO, SO2, and NO/NOy; and site improvements.

Continued investment in PM2.5 continuous monitoring network. Note: many areas already have robust networks.

Telemetry and Data Management Systems to support more timely data reporting and automated validation of data.

Thru-the-probe audit operation of National Performance Audit Program (NPAP) for gas analyzer independent audits. This is to be leveraged with the PEP program.

State Directed Data Analyses - Provide resources through multi-state organizations or other avenues to meet data analysis needs that are of interest to State and local agencies.

National Monitoring Strategy - NCore Level II Precursor Gas Monitoring Implementation FY ’04 – Initial precursor gas method development

OAQPS laboratory study of trace gas monitors FY ’05 – Pilot NCore level II sites for CO, SO2, and NOy at:

OAQPS field study State/local/Tribal agencies:

22 sites have planned funding for FY ‘05 OAP-OAQPS CASTNET collaboration at 3 sites

FY ’06 – Final Rule incorporating National Core Network (NCore)

First Phase of NCore level II implementation FY ‘07

Second phase of NCore level II implementation

Divestments

Low value FRM sites. Largely redundant urban sites or areas that are already covered

by continuous or IMPROVE monitoring and are well below the NAAQS.

Low value supplemental speciation sites. Critical non-trends speciation sites should remain; however,

many of the supplemental speciation sites will no longer be necessary for development of control strategies….note…priority on protecting rural locations and harmonization with IMPROVE

May need objective process for maintaining sites that have other important uses. For example: supporting a local health study source apportionment analysis to reduce emissions voluntarily

Technology Transfer and Training Technology Transfer

EPA - AMTIC web site - www.epa.gov/ttn/amtic/precur.html Availability of precursor gas SOP’s method summaries

Developing Technical Assistance Document (TAD) on precursor gases Data Quality Objectives for precursor gas uses

EPA - AIRNow web site Presentation from recent conference - includes overview of precursor gases

State/local/Tribal/OAQPS/OAP Pilot Conference Calls Calls include spectrum of users from agencies new to these measurements to national

experts in high sensitivity gas monitors. 3 CASTNet pilot sites for precursor gases operational this Spring

Training Planned and Proposed Training Mechanisms

Workshops - including hands-on with equipment Precursor gas monitor workshops scheduled in May and June in RTP NC, more later...

Future? Vendor, Satellite broadcasts, Web based -

Planning for Conference in 2006

Summary and Next Steps 2006 Grant Guidance

Comments received on draft OAR/OAQPS working on an updated version of the guidance

Monitoring Regulations Expect proposal of revised monitoring regulations in support of National

Monitoring Strategy this year. Expect final revised monitoring regulations in 2006

Technology Pilot and training of precursor gas monitors this year Need to develop methods for Ammonia and Nitric Acid Use of AIRNow to support sharing precursor gas, continuous speciation, and

meteorological data New procedures for storing PM2.5 continuous monitoring data in AQS

Communications and Outreach Working to engage EPA Air Division Directors and Air Program Managers Scheduling meeting with Ambient Air Monitoring Steering Committee, June ‘05 Need to engage State Air Directors NCore Level II site selection

Need to engage multiple clients of data with initial list

PM Coarse (PM10 - PM2.5) Notes Second draft of PM Staff Paper available - January 2005 CASAC review meeting held April 2005

EPA-ORD evaluating PM coarse methods CASAC consultation occurred July 2004 New field study with several modified methods scheduled to start April 2005 in Phoenix, AZ. - 28

samplers to be operated. Expecting CASAC Subcommittee review in late summer

Methods Summary Lots of support for continuous methods

Good correlation and precision between methods, Some biases exist between methods

Difference method appears to be strong candidate for use as the method of comparison in performance based approach for approval of other methods

Supporting work underway Development of network DQOs Development of reference method and equivalent method approval criteria Network Design team evaluating issues and options

EPA is working on a timetable according to consent decree negotiated with DOJ. Proposal by December 20th, 2005

PM2.5 Speciation Program Notes More interest in PM continuous speciation

Regions 2, 3, and 4. Recent purchases include Thermo Sulfate and Sunset C analyzers Working to make AIRNow capable of processing continuous

speciation data

Evaluating options for IMPROVE and STN integration Awaiting response from CASAC AAMM Subcommittee

Shipping study Some sites complete Data to be evaluated Other sites only recently started

Contract laboratory costs

0.9 0.95 1 1.05 1.16

4

2

0

2

4

beta (the slope)

alph

a (t

he in

terc

ept)

Draft Federal Equivalent Method approval criteria for PM2.5 Continuous Monitors Data Quality Objective process that links equivalency criteria to expected data

quality in network Extensive statistical investigation with EPA – OAQPS, EPA - ORD, RTI, and Battelle. Expect to propose as applicable to both National Equivalency and Regional

Approved Methods

0.3 0.4 0.5 0.6 0.7 0.80.92

0.93

0.94

0.95

0.96

0.97

0.98

0.99

1

Expected CorrelationApproximate Lower Bound of a 95% Confidence Interval Correlation Lower Bound

Population CV

Cor

rela

tion

Draft Federal Equivalent Method approval criteria for PM2.5 Continuous Monitors Basis of comparison is the FRM

FRM precision <= 7.5% Determine Concentration Coefficient of Variation (CCV)

Used to determine required correlation

Candidate Sampler (the PM2.5 continuous monitor) Precision <=15% - Collocation of two or more monitors of the same

make and model Correlation lower bound (Note correlation, not squared correlation)

0.93 if CCV <0.3 0.87 + 0.2*CCV if 0.3 <= CCV < 0.4 0.95 if 0.4 <= CCV

Multiplicative Bias (the slope or alpha) - must fall between 0.90 and 1.10 Additive Bias (the intercept or beta) is function of multiplicative bias

-0.529 to +3.17 for slopes of 0.90 -3.991 to +0.530 for slope of 1.10

0.3 0.4 0.5 0.6 0.7 0.80.92

0.93

0.94

0.95

0.96

0.97

0.98

0.99

1

Expected CorrelationApproximate Lower Bound of a 95% Confidence Interval Correlation Lower Bound

Population CV

Cor

rela

tion

Correlation was modeled with CCV (population CV).It was determined that sites with larger ranges (e.g. 4 – 80 ug/m3, instead of 4-25 ug/m3)have higher CCV’s and higher expected correlation'sbetween FRM and continuous methods.

Existing correlation requirement is 0.97Blue line represents potential new correlation criteria

Potential New Correlation Criteria

Blue box representsexisting criteria

Red box representspotential new criteria

Existing versus Potential Continuous MonitoringPM2.5 National Equivalency Criteria Bias Criteria

-4

-3

-2

-1

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1

2

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4

0.8 0.85 0.9 0.95 1 1.05 1.1 1.15 1.2

alpha (slope)

bet

a (i

nte

rcep

t)

Analysis of available AQS data to potential PM2.5 equivalency criteria Analysis Basics:

Data downloaded from AQS on 2/3/2005 Dataset includes 4th quarter of 2003 to 3rd quarter of 2004

Latest 4 quarters of data that are generally complete Used collocated FRM/PM2.5 continuous monitoring sites where the

continuous method was the same for the entire period N >= 23 sample pairs Continuous monitor >= 18 valid hours in each day

Used to provide larger data set For actual equivalency testing you would match the same hours on both FRM and

continuous methods FRM range of 3 to 200 ug/m3.

Highest value was 101.7 ug/m3 Analysis limitations:

Did not consider sample precision for either the FRM or continuous monitors Some sites may not be representative of all seasons Only considered data submitted to AQS – Did not attempt to reconcile data

that may be submitted to AIRNow as corrected and AQS as raw.

Potential National PM2.5 Equivalency CriteriaTEOMs with no correction Factor

-6

-4

-2

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2

4

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0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

beta (

intercep

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Potential National PM2.5 Equivalency CriteriaTEOMs with correction factor

-6

-4

-2

0

2

4

6

0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

alpha (slope)

beta (

intercep

t)

Potential National PM2.5 Equivalency CriteriaFDMS

-6

-4

-2

0

2

4

6

0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

beta

(in

tercep

t)

Potential National PM2.5 Equivalency CriteriaCorrelated Radiance Research Nephelometer in WA

-6

-4

-2

0

2

4

6

0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

alpha (slope)

beta (

intercep

t)

Potential National PM2.5 Equivalency CriteriaMet One BAM

-6

-4

-2

0

2

4

6

0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

beta (

intercep

t)

Potential National PM2.5 Equivalency CriteriaAndersen BAM

-6

-4

-2

0

2

4

6

0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

alpha (slope)

beta (

intercep

t)

0.3 0.4 0.5 0.6 0.7 0.80.92

0.93

0.94

0.95

0.96

0.97

0.98

0.99

1

Expected CorrelationApproximate Lower Bound of a 95% Confidence Interval Correlation Lower Bound

Population CV

Corr

elat

ion

Correlation by Population CV

0.65

0.69

0.73

0.77

0.81

0.85

0.89

0.93

0.97

0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Population CV

Co

rrela

tio

n

Biaswithintolerance

Biasoutsidetolerance