## SOUTHWEST RESEARCH INSTITUTE ®

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HTTP://ENGINEANDVEHICLE .SWRI.ORG

ENGINE, EMISSIONS AND VEHICLE RESEARCH DIVISION ISO 9001 C ERTIFIED FAX: (210) 522-3950 ISO 14001 Certified

SAN ANTONIO, TEXAS

HOUSTON, TEXAS i WASHINGTON, DC i ANN ARBOR, MI Date: December 31, 2009

TO: Chris Laroo Environmental Protection Agency

2000 Traverwood Drive Ann Arbor, MI 48105

SUBJECT: Executive Summary Letter Report fo r Work Assignment 4-7, EPA Contract EPC-05-018, under SwRI Project 03.14 658.07, SwRI Proposal No. 03-54802

Contract Title: Testing a nd Analytical Support for Regul ation of Motor Vehicles, Engines, Fuels, and Fuel Additives

Assignment Title: PM-PEMS Measurement Allowance Determination

The United States Environmental Protection Agency (EPA), Engine Manufacturers Association (EMA) and California Air Resources Bo ard (CARB) agreed to pursue a data driven program to establish a measurement allowance (M A) for in-use particulate matter (PM) testing using PM portable emissions measurement systems (PEMS). The PM-PEMS-MA project

includes three main elements:

• Laboratory testing using PM-PEMS

• Monte Carlo simulation using error surfac es generated from la boratory testing to

determine a measurement allowance

• Validation of the measurement allowance using in-use PM-PEMS testing

Three PM-PEMS were accepted by the measurement allowance steering committee (MASC) to be included in the PM-PEMS-MA dete rmination project. The MASC also agreed that the Particle Proportional Micro Diluter (PPMD) by Sensors and the Transient Particulate Matter (TRPM) by Horiba will be used for the official determination and validation of the measurement allowance generated. The third in strument, Micro-Soot Sensor (M SS) by AVL, is not a complete PM-PEMS and it was always used together with the PPMD on this program, based on an agreement reached between Sensors and AVL. The MASC agreed that the MSS will be considered as an option to be used for official measurement allowance determination if both the

PPMD and the TRPM failed to validate.

Based on the Monte Carlo simulation conducted by SwRI using steady- state and transient PM error surfaces, torque and fuel flow error surfaces, and other error surfaces that were generated during the gaseous PEMS-MA, the PPMD produced the lowest positive 95 th percentile measurement allowance of 0.006 g/hp-hr for a th reshold level of 0.02 g/hp-hr. Thus, the PPMD was chosen for in-use testing by CE-CERT to validate the Monte Carlo predicted measurement

allowance.Mr. Chris Laroo Environmental Protection Agency December 31, 2009 Page 2 of 2

SwRI Project 03.14658.07, SwRI Proposal No. 03-54802 As of today, validation testi ng is underway by CE-CERT. Ba sed on the preliminary data generated by CE-CERT and sent to SwRI for va lidation, the PPMD failed th e validation criteria set by the MASC based on the pe rformance of two PPMD in in-u se testing. Testing with the third PPMD is underway, and data are under intensive re view in preparation for a tentatively scheduled Live Meeting on January 14, 2010.

SwRI is currently working on the preparation of a formal final report on this project. The draft final report will be sent to EPA after the validation by CE-CERT is completed and the official data are submitted by CE-CER T to SwRI for model validation.

In order for SwRI to carry on with the projec t efforts, a new Work Assignment is needed for calendar year 2010 to cover th e validation analysis and remainde r of the write-up of a draft final report, and later an offici al final report after review by th e MASC. In addition, the WA will need to cover expenses for conducting and atte nding meetings related to the project by SwRI Principal Investigator a nd other SwRI project team members when necessary.

Prepared by: Approved by:

Imad A. Khalek, Ph.D. Jeff J. White Program Manager Director Emissions Chemistry and Particle Science Emissions R&D Department Emissions R&D Department Engine, Emissions and Vehicle Research

Division

/tyd U:\Davison\wp\PROJECTS\145658.07 EPA Excecutive Summary Report.docx

cc: Patrick Merritt, Project Manager Sherry Twilligear, Contracts Kathleen Roe, EPA Christine Brunner, EPA

SwRI Project Team: Imad Khalek, Ph.D., Program Manager, Principal Investigator Tom Bougher, Research E ngineer, Project Leader Robert Mason, Ph.D., Institute Analys t, Project Co-Investigator/Statistics Janet Buckingham, Staff Analys t, Project Leader/Statistics

This report shall not be reproduced, except in full, without the written approval of Southwest Research Institute. Results and discussion given in this report relate only to the test items described in this report.