NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

Contract No. DE-AC36-08GO28308

Collaborative Lubricating Oil 

Study on Emissions 

November 28, 2006 – March 31, 2011

James N. Carroll, Imad A. Khalek and 

Lawrence R. Smith

Southwest Research Institute 

San Antonio, Texas

Eric Fujita and Barbara Zielinska

Desert Research Institute

Reno, Nevada 

Subcontract Report

NREL/SR-5400-52668

October 2011
NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

National Renewable Energy Laboratory

1617 Cole Boulevard

Golden, Colorado 80401

303-275-3000 • www.nrel.gov

Contract No. DE-AC36-08GO28308

Collaborative Lubricating Oil 

Study on Emissions 

November 28, 2006 – March 31, 2011

James N. Carroll, Imad A. Khalek and 

Lawrence R. Smith

Southwest Research Institute 

San Antonio, Texas

Eric Fujita and Barbara Zielinska

Desert Research Institute

Reno, Nevada

NREL Technical Monitor: Wendy Clark

Prepared under Subcontract No. AEV-7-66409-01

Subcontract Report

NREL/SR-5400-52668

October 2011
This publication was reproduced from the best available copy

submitted by the subcontractor and received no editorial review at NREL.

NOTICE

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COLLABORATIVE LUBRICATING OIL STUDY ON 

EMISSIONS (CLOSE) 

FINAL REPORT

NREL Subcontract Number AEV-7-66409-01

CRC Project Number AVFL-14

SwRI Project Nos. 03.13012 and 03.13029

Prepared for:

Dr. Douglas Lawson

National Renewable Energy Laboratory

1617 Cole Boulevard

Golden, CO 80401

and

Dr. Chris Tennant

Coordinating Research Council

3650 Mansell Road, Suite 140

Alpharetta, GA 30022

Prepared by:

James N. Carroll, Imad A. Khalek, and Lawrence R. Smith

Department of Emissions R&D

Southwest Research Institute

Eric Fujita, Barbara Zielinska

Desert Research Institute

AUGUST 2011
COLLABORATIVE LUBRICATING OIL STUDY ON 

EMISSIONS (CLOSE) 

FINAL REPORT

NREL Subcontract Number AEV-7-66409-01 

CRC Project Number AVFL-14 

SwRI Project Nos. 03.13012 and 03.13029 

Prepared for:

Dr. Douglas Lawson 

National Renewable Energy Laboratory 

1617 Cole Boulevard 

Golden, CO 80401 

and

Dr. Chris Tennant

Coordinating Research Council

3650 Mansell Road, Suite 140 

Alpharetta, GA 30022 

August 2011 

Prepared by: Reviewed by:

________________________________ _____________________________________ 

James N. Carroll, Principal Engineer Kevin A. Whitney, Manager 

Light-Duty Vehicle Emissions Light-Duty Vehicle Emissions

Approved by:

________________________________ 

Jeff J. White, Director 

Emissions R&D Department

ENGINE, EMISSIONS AND VEHICLE RESEARCH DIVISION
ii

FOREWORD

The Department of Emissions Research and Development of Southwest Research 

Institute (SwRI), in conjunction with the Desert Research Institute (DRI), performed this project 

in response to National Renewable Energy Laboratory (NREL) Request for Proposal (RFP) 

Number REV-6-66409, “Investigation of the Role of Lubricating Oil on Particulate Matter 

Emissions from Vehicles” under Subcontract Number AEV-7-66409-1, SwRI Project No. 

03.13012. In addition, the Coordinating Research Council (CRC) augmented this study’s 

funding under CRC Project No. AVFL-14 “Effect of Fuel and Lubricant Composition on the 

Emission of Vehicles, SwRI Project No. 03.13029. The program consisted of extensive 

chemical and physical characterizations of particulate matter (PM) emissions from a limited 

number of gasoline-, diesel- and natural gas-fueled vehicles operating on fresh and aged 

crankcase lubricants in an effort to evaluate the relative contributions of fuels and crankcase 

lubricants on PM and SVOC emissions from vehicles.

The project was performed from November, 2006 to March, 2011. Jim Carroll was the 

principal investigator on this project. Imad Khalek was responsible for the measurement and 

analysis of particle count and size distribution. For the medium- and heavy-duty vehicles, 

Lawrence Smith conducted PM apportionment. Eric Fujita of Desert Research Institute 

apportioned light-duty vehicle PM. Barbara Zielinska of Desert Research Institute coordinated 

all chemical analyses conducted for SwRI under contract. Robert Vara was responsible for all 

lab operations during testing of light- and medium-duty vehicles. Joe Anthony oversaw heavyduty vehicle testing. Kevin Whitney was the overall project manager. 
iii

TABLE OF CONTENTS

Section Page

FOREWORD................................................................................................................................. ii

LIST OF FIGURES ................................................................................................................... viii 

LIST OF TABLES ..................................................................................................................... xiv 

ACKNOWLEDGEMENTS ...................................................................................................... xix 

ACRONYMS & ABBREVIATIONS ....................................................................................... xxi 

EXECUTIVE SUMMARY ..................................................................................................... xxiv 

SUMMARY OF MAJOR TECHNICAL FINDINGS ........................................................ xxviii

1.0 INTRODUCTION .........................................................................................................1

2.0 OBJECTIVE ..................................................................................................................2

3.0 SCOPE OF WORK .......................................................................................................3

4.0 CLOSE PM SOURCE DETERMINATION APPROACH .......................................6

5.0 LUBRICANTS AND FUELS .......................................................................................7

5.1 Lubricants ......................................................................................................................7

5.1.1 Description and Analyses ...............................................................................................7

5.1.2 Hexatriacontane Tracer ...............................................................................................12

5.2 Fuels ..............................................................................................................................13

5.2.1 Light-Duty Vehicles Fuels ...........................................................................................13

5.2.1.1 Cold CO Fuels ...............................................................................................................15

5.2.2 Medium-Duty Vehicle Fuels ........................................................................................17

5.2.3 Heavy-Duty Diesel Fuel ...............................................................................................19

5.2.4 Heavy-Duty Natural Gas Fuel .....................................................................................20

6.0 ANALYTICAL PROCEDURES................................................................................21

6.1 Regulated Emissions ....................................................................................................21

6.1.1 Sampling and Analyses ................................................................................................21

6.2 Non-Regulated Emissions ...........................................................................................21

6.2.1 Particulate Matter and Semi-Volatile Organic Compounds .......................................21

6.2.1.1 Particulate Matter ..........................................................................................................23

6.2.1.2 Semi-Volatile Organic Compounds Media Handling by DRI ......................................24

6.2.2 PM Elemental Analysis by DRI ...................................................................................25

6.2.2.1 Gravimetric Analysis by DRI ........................................................................................25

6.2.2.2 Energy Dispersive X-Ray Fluorescence (EDXRF) by DRI ..........................................25

6.2.2.3 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) by DRI ............................26

6.2.3 Polycyclic Aromatic Hydrocarbons and Alkanes by DRI ...........................................27

6.2.4 Hopanes and Steranes by DRI .....................................................................................27

6.2.5 PM Elemental and Organic Carbon by DRI ...............................................................27

6.2.6 PM Sulfates ...................................................................................................................29

6.2.6.1 Filter Extraction by DRI ................................................................................................29
TABLE OF CONTENTS (CONT’D)

Section Page

iv

6.2.6.2 Ion Chromatographic Analysis for Inorganic Ions and Organic Acids by DRI ............29

6.2.6.3 PM Soluble Organic Fraction by DRI ...........................................................................30

6.3 Particulate Number Count and Size Distribution by SwRI ....................................30

6.3.1 Particle Mass and Size Distribution .............................................................................32

7.0 LIGHT-DUTY VEHICLE TESTS ............................................................................33

7.1 Vehicle Selection and Description ..............................................................................33

7.1.1 Light-Duty Vehicle Selection Criteria .........................................................................33

7.1.2 Light-Duty Normal PM Emitter Vehicle Selection and Description ..........................33

7.1.3 Light-Duty High PM Emitter Vehicle Selection and Description ..............................33

7.1.4 Gaseous and PM Emissions Check-Out Tests ............................................................34

7.2 Lubricants ....................................................................................................................34

7.3 Fuels ..............................................................................................................................35

7.4 Emission Test Procedures ...........................................................................................35

7.4.1 Driving Cycle ................................................................................................................35

7.4.2 Chassis Dynamometer ..................................................................................................37

7.5 Emission Test Results ..................................................................................................37

7.5.1 Regulated Gaseous and PM Mass Emissions ..............................................................37

7.5.1.1 Discussion of Regulated Emission Results ...................................................................44

7.5.2 PM and SVOC Analyses ...............................................................................................45

7.5.2.1 X-Ray Fluorescence (XRF) ...........................................................................................46

7.5.2.2 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Analysis ..........................46

7.5.2.3 Polycyclic Aromatic Hydrocarbons ..............................................................................46

7.5.2.4 Alkanes ..........................................................................................................................46

7.5.2.5 Hopanes and Steranes ....................................................................................................65

7.5.2.6 Particulate-Phase Elemental and Organic Carbon .........................................................65

7.5.2.7 Particulate-Phase Sulfates .............................................................................................65

7.5.2.8 Particulate-Phase Soluble Organic Fraction ..................................................................65

7.5.2.9 Particle Number and Size Distributions ........................................................................70

7.5.2.10 MOUDI Test Results .....................................................................................................84

7.6 PM Apportionment .....................................................................................................87

7.6.1 Composition of Lubricating Oils and Fuels ................................................................87

7.6.2 Components of Exhaust PM ........................................................................................94

7.6.3 Estimates of LOC from Chemical Components of Exhaust PM and Lubricating Oil96

7.6.4 Estimation of Fuel-Combustion and Oil Contributions by Multiple Regression ......96

7.6.5 Conclusions ...................................................................................................................97

7.7 Light-Duty Gasoline Vehicles Major Technical Findings .......................................99

8.0 MEDIUM-DUTY VEHICLE TESTS ......................................................................101

8.1 Vehicle Selection and Description ............................................................................101

8.1.1 Medium-Duty Vehicle Selection Criteria ..................................................................101

8.1.2 Medium-Duty Normal PM Emitter Vehicle Selection and Description ...................101
TABLE OF CONTENTS (CONT’D)

Section Page

v 

8.1.3 Medium-Duty High PM Emitter Vehicle Selection and Description .......................101

8.1.4 Gaseous and PM Emissions Check-Out Tests ..........................................................102

8.2 Lubricants ..................................................................................................................103

8.3 Fuels ............................................................................................................................104

8.4 Emission Test Procedures .........................................................................................104

8.4.1 Driving Cycle ..............................................................................................................104

8.4.2 Chassis Dynamometer ................................................................................................105

8.5 Emission Test Results ................................................................................................105

8.5.1 Regulated Gaseous and PM Mass Emissions ............................................................105

8.5.1.1 Medium-Duty Normal PM Emissions Vehicle ...........................................................105

8.5.1.2 Medium-Duty High PM Emissions Vehicle ...............................................................108

8.5.1.3 Discussion of Regulated Emissions Results ................................................................109

8.5.2 PM and SVOC Analyses .............................................................................................113

8.5.2.1 X-Ray Fluorescence (XRF) .........................................................................................114

8.5.2.2 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Analysis ........................114

8.5.2.3 Polycyclic Aromatic Hydrocarbons ............................................................................114

8.5.2.4 Alkanes ........................................................................................................................114

8.5.2.5 Hopanes and Steranes ..................................................................................................114

8.5.2.6 Particle-Phase Elemental and Organic Carbon ...........................................................134

8.5.2.7 Particle-Phase Sulfates ................................................................................................134

8.5.2.8 Particle-Phase Soluble Organic Fraction .....................................................................135

8.5.2.9 Particle Number and Size Distribution ........................................................................136

8.6 PM Apportionment ...................................................................................................149

8.6.1 Regulated Emissions and Fuel Economy ..................................................................150

8.6.2 Estimates for Vehicle Oil Consumption Rates ..........................................................151

8.6.3 Wear Elements ............................................................................................................152

8.6.4 Carbon Analyses for “Elemental” and “Organic” Content of PM ..........................153

8.6.5 Estimation of Unburned Oil Content in PM .............................................................154

8.6.6 PAH PM Emissions ....................................................................................................156

8.6.7 PM Apportionment Summary ....................................................................................157

8.7 Medium-Duty Diesel Vehicles Major Technical Findings .....................................158

9.0 HEAVY-DUTY NATURAL GAS VEHICLE TESTS ...........................................160

9.1 Vehicle Selection and Description ............................................................................160

9.1.1 Heavy-Duty Natural Gas Vehicle Selection Criteria ................................................160

9.1.2 Heavy-Duty Natural Gas Vehicle Selection and Description ...................................160

9.1.3 Gaseous and PM Emissions Check-out Tests ...........................................................161

9.2 Lubricants ..................................................................................................................163

9.3 Fuels ............................................................................................................................163

9.4 Emission Test Procedures .........................................................................................163

9.4.1 Driving Cycle ..............................................................................................................163
TABLE OF CONTENTS (CONT’D)

Section Page

vi 

9.4.2 Chassis Dynamometer ................................................................................................164

9.5 Heavy-Duty Natural Gas Vehicles Emission Test Results .....................................165

9.5.1 Regulated Gaseous and PM Emissions .....................................................................165

9.5.1.1 Discussion of Regulated Emissions Results ................................................................167

9.5.2 PM and SVOC Analyses .............................................................................................170

9.5.2.1 X-Ray Fluorescence (XRF) .........................................................................................170

9.5.2.2 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Analysis ........................170

9.5.2.3 Polycyclic Aromatic Hydrocarbons ............................................................................170

9.5.2.4 Alkanes ........................................................................................................................170

9.5.2.5 Hopanes and Steranes ..................................................................................................171

9.5.2.6 Particle-Phase Elemental and Organic Carbon ...........................................................171

9.5.2.7 Particulate-Phase Sulfates ...........................................................................................171

9.5.2.8 Particulate-Phase Soluble Organic Fraction ................................................................171

9.5.2.9 Particle Number and Size Distribution Emission Test Results ...................................183

9.6 PM Apportionment Summary .................................................................................190

9.6.1 Regulated Emissions and Fuel Economy ..................................................................191

9.6.2 Estimates for Vehicle Oil Consumption Rates ..........................................................191

9.6.3 Wear Elements ............................................................................................................192

9.6.4 Carbon Analyses for “Elemental” and “Organic” Content of PM ..........................192

9.6.5 Estimation of Unburned Oil Content .........................................................................193

9.6.6 PAH PM Emissions ....................................................................................................194

9.6.7 Summary .....................................................................................................................195

9.7 Heavy-Duty Natural Gas Vehicles Major Technical Findings ..............................195

10.0 HEAVY-DUTY DIESEL VEHICLE TESTS .........................................................198

10.1 Vehicle Selection and Description ............................................................................198

10.1.1 Heavy-Duty Diesel Vehicle Selection Criteria ...........................................................198

10.1.2 Heavy-Duty Diesel Vehicle Selection and Description .............................................198

10.1.3 Gaseous and PM Emissions Check-out Tests ...........................................................200

10.2 Lubricants ..................................................................................................................201

10.3 Fuels ............................................................................................................................201

10.4 Emission Test Procedures .........................................................................................201

10.4.1 Driving Cycle ..............................................................................................................202

10.4.2 Chassis Dynamometer ................................................................................................202

10.5 Heavy-Duty Diesel Vehicles Emission Test Results ................................................202

10.5.1 Regulated Gaseous and PM Emissions .....................................................................202

10.5.1.1 Discussion of Regulated Emissions Results ................................................................202

10.5.2 PM and SVOC Analyses .............................................................................................206

10.5.2.1 X-Ray Fluorescence (XRF) .........................................................................................206

10.5.2.2 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Analysis ........................206

10.5.2.3 Polycyclic Aromatic Hydrocarbons ............................................................................206
TABLE OF CONTENTS (CONT’D)

Section Page

vii 

10.5.2.4 Alkanes ........................................................................................................................214

10.5.2.5 Hopanes and Steranes ..................................................................................................214

10.5.2.6 Particle-Phase Elemental and Organic Carbon ...........................................................214

10.5.2.7 Particle-Phase Sulfates ................................................................................................214

10.5.2.8 Particle-Phase Soluble Organic Fraction .....................................................................214

10.5.2.9 Particle Number and Size Distribution Emission Test Results ...................................217

10.6 PM Apportionment ...................................................................................................224

10.6.1 Regulated Emissions and Fuel Economy ..................................................................224

10.6.2 Estimates for Vehicle Oil Consumption Rates ..........................................................225

10.6.3 Wear Elements ............................................................................................................226

10.6.4 Carbon Analyses for Elemental and Organic Content of PM ..................................226

10.6.5 Estimation of Unburned Oil Content .........................................................................227

10.6.6 PAH PM Emissions ....................................................................................................228

10.6.7 Summary .....................................................................................................................229

10.7 Heavy-Duty Diesel Vehicles Major Technical Findings ........................................229

11.0 FUTURE WORK ......................................................................................................232

REFERENCES ...........................................................................................................................233

APPENDICES No. of Pages

A - HEXATRIACONTANE TRACER BLENDING PROTOCOL .............................................4 

B - TWO COLD CO FUELS ANALYSES RESULTS ................................................................5 

C - LUBRIZOL LETTER REPORT-LIGHT-DUTY HIGH PM EMISSIONS VEHICLE .........8 

D - DESERT RESEARCH INSTITUTE REPORT ON RENO FUELS ......................................2 

E - HEAVY-DUTY SMOKER REPORT ON CPS VEHICLES .................................................3 
viii

LIST OF FIGURES

Figure Page

 1. COMPARISON OF TWO COLD CO FUELS SHOWING COMPONENTS

WITH GREATER THAN 0.5 PERCENT DIFFERENCE .......................................... 16

 2. COMPARISON OF TWO COLD CO FUELS SHOWING ALL SPECIES AS 

PERCENTAGES OF EACH FUEL ............................................................................... 16

 3. MULTIPLE PM SAMPLING PROBE INSERT .......................................................... 22

 4. MULTIPLE PM SAMPLING PROBE INSERTED IN LIGHT-DUTY

DILUTION TUNNEL ...................................................................................................... 23

 5. EXPERIMENTAL SETUP FOR PARTICLE SIZE AND NUMBER 

MEASUREMENTS .......................................................................................................... 31

 6. LA92 UNIFIED DRIVING CYCLE (UDC) .................................................................. 36

 7. LIGHT-DUTY AVERAGE HYDROCARBON EMISSION RATES ......................... 40

 8. LIGHT-DUTY AVERAGE CARBON MONOXIDE EMISSION RATES ................ 41

 9. LIGHT-DUTY AVERAGE OXIDES OF NITROGEN EMISSION RATES ............ 41

 10. LIGHT-DUTY AVERAGE OXIDES OF NITROGEN EMISSION RATES – 

EXPANDED SCALE ....................................................................................................... 42

 11. LIGHT-DUTY AVERAGE FUEL ECONOMY ........................................................... 42

 12. LIGHT-DUTY AVERAGE PARTICULATE MATTER EMISSION RATES ......... 43

 13. LIGHT-DUTY AVERAGE PARTICULATE MATTER EMISSION RATES – 

EXPANDED SCALE ....................................................................................................... 43

 14. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (LIGHTDUTY, NORMAL EMITTER, FRESH OIL) ................................................................ 71

 15. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (LIGHTDUTY, NORMAL EMITTER, AGED OIL) ................................................................. 71

 16. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (LIGHT-DUTY, NORMAL EMITTER, FRESH OIL) ........................ 72

 17. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL 

PARTICLES (LIGHT-DUTY, NORMAL EMITTER, AGED OIL) .......................... 72

 18. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (LIGHTDUTY, HIGH EMITTER, FRESH OIL) ....................................................................... 74

 19. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (LIGHTDUTY, HIGH EMITTER, AGED OIL) ......................................................................... 74

 20. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (LIGHT-DUTY, HIGH EMITTER, FRESH OIL) ............................... 75

 21. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (LIGHT-DUTY, HIGH EMITTER, AGED OIL) ................................. 75

 22. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, NORMAL

EMITTER, FRESH OIL) ................................................................................................ 76

 23. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 72°F, NORMAL 

EMITTER, FRESH OIL) ................................................................................................ 76
LIST OF FIGURES (CONT’D)

Figure Page

ix

 24. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 20°F, NORMAL 

EMITTER, FRESH OIL) ................................................................................................ 77

 25. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 20°F, NORMAL 

EMITTER, FRESH OIL) ................................................................................................ 77

 26. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, NORMAL 

EMITTER, AGED OIL) .................................................................................................. 78

 27. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 72°F, NORMAL 

EMITTER, AGED OIL) .................................................................................................. 78

 28. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 20°F, NORMAL 

EMITTER, AGED OIL) .................................................................................................. 79

 29. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 20°F, NORMAL 

EMITTER, AGED OIL) .................................................................................................. 79

 30. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, NORMAL 

EMITTER, FRESH OIL, REPEATED TEST AFTER E0, E10 WITH 

FRESH OIL) ..................................................................................................................... 80

 31. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, HIGH EMITTER,

FRESH OIL) ..................................................................................................................... 80

 32. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 72°F, HIGH EMITTER, 

FRESH OIL) ..................................................................................................................... 81

 33. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 20°F, HIGH EMITTER,

FRESH OIL) ..................................................................................................................... 81

 34. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 20°F, HIGH EMITTER, 

FRESH OIL) ..................................................................................................................... 82

 35. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, HIGH EMITTER,

AGED OIL) ....................................................................................................................... 82

 36. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 72°F, HIGH EMITTER,

AGED OIL) ....................................................................................................................... 83

 37. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 20°F, HIGH EMITTER,

AGED OIL) ....................................................................................................................... 83

 38. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 20°F, HIGH EMITTER,

AGED OIL) ....................................................................................................................... 84

 39. SIZE SPECIFIC CUMULATIVE MASS FRACTION ................................................ 85

 40. SIZE-SPECIFIC ELEMENTS AS A PERCENT OF TOTAL PM ............................. 86

 41. ELEMENTAL COMPOSITION AS A PERCENT OF TOTAL PM MASS ............. 86

 42. COMPOSITION OF INDIVIDUAL HOPANES AND STERANES FROM FUEL 

AND OIL RELATIVE TO MEASURED EXHAUST EMISSIONS RATES ............. 92

 43. MEDIUM-DUTY NORMAL EMITTER PHASE-BY-PHASE COMPOSITE 

FILTERS COMPARISON ............................................................................................ 108

 44. MEDIUM-DUTY VEHICLES’ AVERAGE HYDROCARBON EMISSION

RATES ............................................................................................................................. 110
LIST OF FIGURES (CONT’D)

Figure Page

x 

 45. MEDIUM-DUTY VEHICLES’ AVERAGE CARBON MONOXIDE 

EMISSION RATES ........................................................................................................ 110

 46. MEDIUM-DUTY VEHICLES’ AVERAGE OXIDES OF NITROGEN 

EMISSION RATES ........................................................................................................ 112

 47. MEDIUM-DUTY VEHICLES’ AVERAGE FUEL ECONOMY .............................. 112

 48. MEDIUM-DUTY VEHICLES’ AVERAGE PARTICULATE MATTER 

EMISSION RATES ........................................................................................................ 113

 49. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(MEDIUM-DUTY, NORMAL EMITTER, FRESH OIL) ......................................... 137

 50. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(MEDIUM-DUTY, NORMAL EMITTER, AGED OIL) ........................................... 137

 51. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (MEDIUM-DUTY, NORMAL EMITTER, FRESH OIL) ................. 138

 52. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (MEDIUM-DUTY, NORMAL EMITTER, AGED OIL) ................... 138

 53. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(MEDIUM-DUTY, HIGH EMITTER, FRESH OIL) ................................................. 139

 54. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(MEDIUM-DUTY, HIGH EMITTER, AGED OIL) .................................................. 140

 55. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (MEDIUM-DUTY, HIGH EMITTER, FRESH OIL) ......................... 140

 56. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (MEDIUM-DUTY, HIGH EMITTER, AGED OIL) ........................... 141

 57. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 72°F, MEDIUM-DUTY, 

NORMAL EMITTER, FRESH OIL) ........................................................................... 141

 58. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 72°F, MEDIUM-DUTY, 

NORMAL EMITTER, FRESH OIL) ........................................................................... 142

 59. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 20°F, MEDIUM-DUTY, 

NORMAL EMITTER, FRESH OIL) ........................................................................... 142

 60. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 20°F, MEDIUM-DUTY, 

NORMAL EMITTER, FRESH OIL) ........................................................................... 143

 61. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 72°F, MEDIUM-DUTY, 

NORMAL EMITTER, AGED OIL) ............................................................................. 143

 62. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 72°F, MEDIUM-DUTY, 

NORMAL EMITTER, AGED OIL) ............................................................................. 144

 63. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 20°F, MEDIUM-DUTY, 

NORMAL EMITTER, AGED OIL) ............................................................................. 144

 64. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 20°F, MEDIUM-DUTY, 

NORMAL EMITTER, AGED OIL) ............................................................................. 145
LIST OF FIGURES (CONT’D)

Figure Page

xi 

 65. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 72°F, MEDIUM-DUTY,

HIGH EMITTER, FRESH OIL) .................................................................................. 145

 66. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 72°F, MEDIUM-DUTY,

HIGH EMITTER, FRESH OIL) .................................................................................. 146

 67. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 20°F, MEDIUM-DUTY,

HIGH EMITTER, FRESH OIL) .................................................................................. 146

 68. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 20°F, MEDIUM-DUTY,

HIGH EMITTER, FRESH OIL) .................................................................................. 147

 69. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 72°F, MEDIUM-DUTY,

HIGH EMITTER, AGED OIL) .................................................................................... 147

 70. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 72°F, MEDIUM-DUTY,

HIGH EMITTER, AGED OIL) .................................................................................... 148

 71. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 20°F, MEDIUM-DUTY,

HIGH EMITTER, AGED OIL) .................................................................................... 148

 72. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 20°F, MEDIUM-DUTY,

HIGH EMITTER, AGED OIL) .................................................................................... 149

 73. HEAVY-DUTY UDDS (HDDC) CYCLE ..................................................................... 164

 74. HYDROCARBON EMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE NATURAL GAS BUSES .................................. 167

 75. CARBON MONOXIDE EMISSION RATES FROM THE NORMAL PM

EMITTER AND HIGH MILEAGE NATURAL GAS BUSES .................................. 168

 76. OXIDES OF NITROGEN EMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE NATURAL GAS BUSES .................................. 168

 77. FUEL CONSUMPTION OF THE NORMAL PM EMITTER AND HIGH

MILEAGE NATURAL GAS BUSES ........................................................................... 169

 78. PARTICULATE MATTER EMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE NATURAL GAS BUSES .................................. 169

 79. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(NATURAL GAS, NORMAL EMITTER, FRESH OIL) ........................................... 184

 80. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(NATURAL GAS, NORMAL EMITTER, AGED OIL) ............................................ 184

 81. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (NATURAL GAS, NORMAL EMITTER, FRESH OIL) ................... 185

 82. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (NATURAL GAS, NORMAL EMITTER, AGED OIL) .................... 185

 83. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(NATURAL GAS, HIGH MILEAGE EMITTER, FRESH OIL) .............................. 186

 84. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(NATURAL GAS, HIGH MILEAGE EMITTER, AGED OIL) ............................... 186
LIST OF FIGURES (CONT’D)

Figure Page

xii 

 85. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (NATURAL GAS, HIGH MILEAGE EMITTER, FRESH OIL) ...... 187

 86. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (NATURAL GAS, HIGH MILEAGE EMITTER, AGED OIL) ....... 187

 87. NUMBER-WEIGHTED SIZE DISTRIBUTION (NATURAL GAS, NORMAL 

EMITTER, FRESH OIL) .............................................................................................. 188

 88. NUMBER-WEIGHTED SIZE DISTRIBUTION (NATURAL GAS, NORMAL 

EMITTER, AGED OIL) ................................................................................................ 189

 89. NUMBER-WEIGHTED SIZE DISTRIBUTION (NATURAL GAS,

HIGH MILEAGE EMITTER, FRESH OIL) .............................................................. 189

 90. NUMBER-WEIGHTED SIZE DISTRIBUTION (NATURAL GAS,

HIGH MILEAGE EMITTER, AGED OIL) ................................................................ 190

 91. HYDROCARBON EMISSION RATES FROM THE NORMAL PM EMITTER

AND HIGH MILEAGE DIESEL BUSES .................................................................... 203

 92. CARBON MONOXIDE EMISSION RATES FROM THE NORMAL PM

EMITTER AND HIGH MILEAGE DIESEL BUSES ................................................ 204

 93. OXIDES OF NITROGENEMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE DIESEL BUSES ................................................ 204

 94. FUEL CONSUMPTION OF THE NORMAL PM EMITTER AND HIGH

MILEAGE DIESEL BUSES ......................................................................................... 205

 95. PARTICULATE MATTER EMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE DIESEL BUSES ................................................ 205

 96. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(DIESEL, NORMAL EMITTER, FRESH OIL) ......................................................... 218

 97. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(DIESEL, NORMAL EMITTER, AGED OIL) ........................................................... 218

 98. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (DIESEL, NORMAL EMITTER, FRESH OIL) ................................. 219

 99. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (DIESEL, NORMAL EMITTER, AGED OIL) ................................... 219

 100. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(DIESEL, HIGH MILEAGE VEHICLE, FRESH OIL) ............................................ 220

 101. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(DIESEL, HIGH MILEAGE VEHICLE, AGED OIL) .............................................. 221

 102. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (HD DIESEL, HIGH MILEAGE VEHICLE, FRESH OIL) ............. 221

 103. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL

PARTICLES (HD DIESEL, HIGH MILEAGE VEHICLE, AGED OIL) ............... 222

 104. NUMBER-WEIGHTED SIZE DISTRIBUTION (HD DIESEL, NORMAL 

EMITTER, FRESH OIL) .............................................................................................. 222
LIST OF FIGURES (CONT’D)

Figure Page

xiii

 105. NUMBER-WEIGHTED SIZE DISTRIBUTION (HD DIESEL, NORMAL 

EMITTER, AGED OIL) ................................................................................................ 223

 106. NUMBER-WEIGHTED SIZE DISTRIBUTION (HD DIESEL, HIGH

MILEAGE VEHICLE, FRESH OIL) .......................................................................... 223

 107. NUMBER-WEIGHTED SIZE DISTRIBUTION (HD DIESEL, HIGH

MILEAGE VEHICLE, AGED OIL) ............................................................................ 224
xiv 

LIST OF TABLES

Table Page

 1. PROJECT TEST MATRIX .............................................................................................. 4

 2. CLOSE PROJECT TEST CODES ................................................................................... 5

 3. PROJECT LUBRICANTS SUPPLIED BY AMERICAN CHEMISTRY 

COUNCIL MEMBERS ..................................................................................................... 8

 4. LIGHT-DUTY OIL ANALYSES FROM SUPPLIER .................................................... 9

 5. MEDIUM-DUTY OIL ANALYSES FROM SUPPLIER ............................................. 10

 6. HEAVY-DUTY NATURAL GAS OIL ANALYSES FROM SUPPLIER .................. 11

 7. HEAVY-DUTY DIESEL OIL ANALYSES FROM SUPPLIER ................................. 12

 8. SUMMARY OF FUELS FOR LIGHT-DUTY VEHICLES ........................................ 13

 9. ANALYTICAL RESULTS FOR LIGHT-DUTY FUELS ............................................ 14

 10. COLD CO FUEL COMPONENTS WITH GREATER THAN 0.5% 

DIFFERENCE .................................................................................................................. 15

 11. ANALYTICAL RESULTS FOR MEDIUM-DUTY FUELS ....................................... 18

 12. ANALYTICAL RESULTS FOR HEAVY-DUTY DIESEL FUELS ........................... 19

 13. NATURAL GAS FUEL BLENDS FOR HEAVY-DUTY VEHICLES ....................... 20

 14. DILUTION RATIO USED FOR DIFFERENT VEHICLES ....................................... 31

 15. TEST MATRIX USED FOR EACH VEHICLE, FUEL AND OIL 

COMBINATION .............................................................................................................. 32

 16. LIGHT-DUTY HIGH EMITTER FOUR-PHASE UNIFIED CYCLE PM 

EMISSION RATE REPEATABILITY CHECK, mg/mi ............................................. 34

 17. COMPOSITE UNIFIED CYCLE GASEOUS EMISSION RATE 

REPEATABILITY CHECK, g/mi .................................................................................. 34

 18. LIGHT-DUTY NORMAL PM EMITTER VEHICLE AT 72°F ................................. 38

 19. LIGHT-DUTY NORMAL PM EMTTER VEHICLE AT 20°F .................................. 38

 20. LIGHT-DUTY HIGH PM EMITTER VEHICLE AT 72°F ........................................ 39

 21. LIGHT-DUTY HIGH PM EMITTER VEHICLE AT 20°F ........................................ 39

 22. COMPARISON OF INITIAL AND REPEAT TEST OF LIGHT-DUTY 

NORMAL PM EMITTER ............................................................................................... 40

 23. AVERAGE RESULTS OF LIGHT-DUTY VEHICLE PM ELEMENTAL 

ANALYSIS BY XRF, μg/mi ............................................................................................ 47

 24. AVERAGE RESULTS OF LIGHT-DUTY VEHICLE PM ELEMENTAL 

ANALYSIS BY ICP-MS, μg/mi ...................................................................................... 49

 25. LIGHT-DUTY VEHICLE ELEMENTAL ANALYSIS OF FUELS AND 

LUBRICANTS BY ICP-MS, ng/g ................................................................................... 50

 26. POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST, μg/mi ................ 51

 27. LIGHT-DUTY VEHICLE FUELS AND LUBRICANTS POLYCYCLIC 

AROMATIC HYDROCARBONS, μg/g ........................................................................ 55

 28. POLYCYCLIC AROMATIC HYDROCARBONS SPECIES CODES ...................... 59

 29. LIGHT-DUTY VEHICLE AVERAGE ALKANES IN EXHAUST, μg/mi ................ 60

 30. ALKANES SPECIES CODES ........................................................................................ 62
LIST OF TABLES (CONT’D)

Table Page

xv 

 31. LIGHT-DUTY VEHICLE ALKANES IN FUELS AND LUBRICANTS .................. 63

 32. LIGHT-DUTY VEHICLE HOPANES AND STERANES IN EXHAUST, μg/mi ..... 66

 33. HOPANES AND STERANES SPECIES CODES ........................................................ 67

 34. LIGHT-DUTY VEHICLE HOPANES AND STERANES IN FUELS AND 

LUBRICANTS, μg/g ........................................................................................................ 68

 35. LIGHT-DUTY ELEMENTAL CARBON AND ORGANIC CARBON ..................... 69

 36. AVERAGE SULFATE EMISSIONS FROM LIGHT-DUTY VEHICLES ................ 69

 37. LIGHT DUTY VEHICLE AVERAGE SOLUBLE ORGANIC FRACTION ............ 70

 38. CONCENTRATIONS OF OIL ADDITIVE ELEMENTS, HOPANES, 

STERANES, ALKANES AND POLYCYCLIC AROMATIC HYDROCARBONS 

(μg/g) IN FRESH AND AGED LUBRICATING OILS, AND GASOLINES

WITH ZERO OR 10% ETHANOL BY VOLUME ..................................................... 88

 39. PARTICLE-PHASE EXHAUST EMISSION RATES (TUNNEL BLANK 

SUBTRACTED) OF OIL ADDITIVE AND ENGINE WEAR ELEMENTS, 

HOPANES AND STERANES (H&S), IDENTIFIED AND UNRESOLVED 

COMPLEX MIXTURE (UCM) OF ALKANES AND CYCLOALKANES, 

DEUTERATED HEXATRIACONTANE, PAH AND SUM OF THREE HIGHMW PAH COLLECTED ON TEFLON-IMPREGNATED GLASS FIBER 

(TIGF) FILTERS ............................................................................................................. 90

 40. LUBRICATING OIL CONSUMPTION RATES BASED UPON RATIOS OF 

THE EMISSION RATES OF ELEMENTAL TRACERS, UCM, SUM OF 

HOPANES AND STERANES, AND DEUTERATED HEXATRIACONTANE 

TO THEIR CONCENTRATIONS IN THE CORRESPONDING 

LUBRICATING OIL ....................................................................................................... 93

 41. VOLATILE PHASE OF SEMI-VOLATILE COMPOUNDS EXHAUST 

EMISSION RATES (TUNNEL BLANK SUBTRACTED) OF IDENTIFIED 

HOPANES AND STERANES (H&S), IDENTIFIED AND UNRESOLVED 

COMPLEX MIXTURE (UCM) OF ALKANES AND CYCLOALKANES, 

DEUTERATED HEXATRIACONTANE, PAH AND SUM OF 3 HIGH-MW 

PAH1 COLLECTED ON BACKUP XAD-4 CARTRIDGES ....................................... 95

 42. LUBRICATING OIL AND FUEL COMBUSTION CONTRIBUTIONS TO 

TOTAL CARBON EMISSIONS BASED UPON MULTIPLE LINEAR 

REGRESSION USING ELEMENTAL TRACERS, UCM, SUM OF HOPANES 

AND STERANES, AND DEUTERATED HEXATRIACONTANE AS 

ALTERNATIVE TRACERS FOR OIL CONTRIBUTIONS AND HIGHMOLECULAR WEIGHT PAH AS THE FUEL COMBUSTION TRACER ............ 98

 43. CHECK-OUT TEST RESULTS FROM THE MEDIUM-DUTY NORMAL 

PM EMITTING VEHICLE EMISSIONS AND FUEL ECONOMY 

REPEATABILITY TESTS ........................................................................................... 103
LIST OF TABLES (CONT’D)

Table Page

xvi 

 44. CHECK-OUT TEST RESULTS FROM THE MEDIUM-DUTY HIGH PM 

EMITTING VEHICLE EMISSIONS AND FUEL ECONOMY 

REPEATABILITY TESTS ........................................................................................... 103

 45. MEDIUM-DUTY NORMAL PM EMITTING VEHICLE AT 72°F ........................ 106

 46. MEDIUM-DUTY NORMAL PM EMITTING VEHICLE AT 20°F ........................ 106

 47. SUMMARY OF PHASE-BY-PHASE AND COMPOSITE PM EMISSION 

RATES FROM THE MEDIUM-DUTY NORMAL EMITTING VEHICLE .......... 107

 48. MEDIUM-DUTY HIGH PM EMITTING VEHICLE AT 72°F ................................ 108

 49. MEDIUM-DUTY HIGH PM EMITTING VEHICLE AT 20°F ................................ 109

 50. AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE PM ELEMENTAL 

ANALYSIS BY XRF, μg/mi .......................................................................................... 115

 51. MEDIUM-DUTY VEHICLE LUBRICANTS AND FUELS ELEMENTS 

BY XRF ........................................................................................................................... 117

 52. AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE PM ELEMENTAL 

ANALYSIS BY ICP-MS, μg/mi .................................................................................... 119

 53. MEDIUM-DUTY VEHICLE LUBRICANTS AND FUELS ELEMENTS 

BY ICP-MS ..................................................................................................................... 120

 54. AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE EXHAUST 

POLYCYCLIC AROMATIC HYDROCARBONS, μg/mi ........................................ 121

 55. MEDIUM-DUTY VEHICLE POLYCYCLIC AROMATIC 

HYDROCARBONS IN LUBRICANTS AND FUEL .................................................. 126

 56. MEDIUM-DUTY VEHICLE AVERAGE ALKANES IN EXHAUST, μg/mi ......... 129

 57. MEDIUM-DUTY VEHICLE ALKANES IN FUELS AND LUBRICANTS ............ 131

 58. AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE EXHAUST 

HOPANES AND STERANES, μg/mi ........................................................................... 132

 59. MEDIUM-DUTY VEHICLE LUBRICANTS AND FUELS HOPANES AND 

STERANES ..................................................................................................................... 133

 60. MEDIUM-DUTY VEHICLE PARTICULATE ELEMENTAL CARBON AND 

ORGANIC CARBON .................................................................................................... 134

 61. AVERAGE SULFATE EMISSIONS FROM MEDIUM-DUTY VEHICLES ......... 135

 62. MEDIUM-DUTY VEHICLES AVERAGE PARTICLE-PHASE SOLUBLE 

ORGANIC FRACTION ................................................................................................ 136

 63. REGULATED EMISSIONS AND FUEL ECONOMY, NORMAL EMITTER ...... 150

 64. REGULATED EMISSIONS AND FUEL ECONOMY, HIGH EMITTER ............. 151

 65. ELEMENTS FROM OIL IN PM .................................................................................. 152

 66. ELEMENTS FROM WEAR, μg/mi (AVERAGES FOR EACH VEHICLE) .......... 153

 67. TEST VARIABLE IMPACT ON SELECTED WEAR ELEMENTS ...................... 153

 68. TOTAL, “ELEMENTAL,” AND “ORGANIC” CARBON EMISSIONS ................ 153
LIST OF TABLES (CONT’D)

Table Page

xvii 

 69. CARBON AND OTHER ELEMENT TOTALS COMPARED TO TOTAL 

PM, AVERAGES, mg/mi ............................................................................................... 154

 70. COMPARISON OF UNBURNED OIL ESTIMATES TO OC .................................. 155

 71. DISPLACEMENT OF LIGHTER ALKANES FROM HE PM AT LOWER 

TEST TEMPERATURE ................................................................................................ 156

 72. TEMPERATURE AND OXIDATION CATALYST EFFECT ON SELECTED 

EMISSIONS RATES ..................................................................................................... 156

 73. DISPLACEMENT OF LIGHTER PAHS FROM HE PM AT LOWER TEST 

TEMPERATURE ........................................................................................................... 157

 74. DESCRIPTION OF HEAVY-DUTY NATURAL GAS BUSES ................................ 161

 75. SUMMARY OF REPEATABILITY CHECK TEST RESULTS FROM THE 

HEAVY-DUTY NORMAL PM EMITTING NATURAL GAS VEHICLE ............. 162

 76. SUMMARY OF REPEATABILITY CHECK TEST RESULTS FROM THE 

HEAVY-DUTY HIGH MILEAGE NATURAL GAS VEHICLE ............................. 162

 77. AVERAGE REGULATED EMISSIONS FROM HEAVY-DUTY NATURAL 

GAS VEHICLES ............................................................................................................ 165

 78. SUMMARY OF NORMAL EMITTER BUS TANK AND SWRI BLENDED 

NATURAL GAS FUEL ANALYSES ........................................................................... 166

 79. SUMMARY AVERAGE HEAVY-DUTY NATURAL GAS VEHICLE PM 

AND LUBRICANT ELEMENTAL ANALYSIS BY XRF ......................................... 172

 80. RESULTS OF HEAVY-DUTY NATURAL GAS PM AND LUBRICANTS 

ELEMENTAL ANALYSIS BY ICP-MS ..................................................................... 174

 81. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE POLYCYCLIC 

AROMATIC HYDROCARBONS IN EXHAUST AND LUBRICANTS ................. 175

 82. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE ALKANES IN 

EXHAUST AND LUBRICANTS .................................................................................. 179

 83. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE HOPANES AND 

STERANES IN EXHAUST AND LUBRICANTS ...................................................... 181

 84. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE ELEMENTAL 

CARBON AND ORGANIC CARBON RATES .......................................................... 182

 85. AVERAGE SULFATE EMISSIONS FROM HEAVY-DUTY NATURAL 

GAS VEHICLES ............................................................................................................ 182

 86. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE SOLUBLE 

ORGANIC FRACTION ................................................................................................ 182

 87. REGULATED EMISSIONS AND FUEL ECONOMY FOR HEAVY-DUTY 

NATURAL GAS-FUELED VEHICLES ...................................................................... 191

 88. ESTIMATED OIL CONSUMPTION RATES USING BOTH XRF & ICPMS DATA ........................................................................................................................ 192

 89. TOTAL, ELEMENTAL, AND ORGANIC CARBON EMISSIONS ........................ 193
LIST OF TABLES (CONT’D)

Table Page

xviii 

 90. CARBON AND OTHER ELEMENT TOTALS COMPARED TO TOTAL PM .... 193

 91. COMPARISON OF UNBURNED OIL ESTIMATES TO OC .................................. 194

 92. DESCRIPTION OF HEAVY-DUTY DIESEL BUSES .............................................. 199

 93. RESULTS OF THREE REPEATABILITY CHECK EMISSION TESTS 

PERFORMED WITH THE HEAVY-DUTY NORMAL PM EMITTING 

DIESEL BUS AS RECEIVED ...................................................................................... 200

 94. RESULTS OF THREE REPEATABILITY CHECK EMISSION TESTS 

PERFORMED WITH THE HEAVY-DUTY HIGH-MILEAGE DIESEL 

BUS AS RECEIVED ...................................................................................................... 201

 95. AVERAGE REGULATED EMISSIONS FROM HEAVY-DUTY DIESEL 

VEHICLES ..................................................................................................................... 203

 96. AVERAGE HEAVY-DUTY DIESEL PM ELEMENTAL ANALYSIS BY XRF ... 207

 97. RESULTS OF HEAVY-DUTY DIESEL PM, LUBRICANTS, AND FUEL 

ELEMENTAL ANALYSIS BY ICP-MS ..................................................................... 209

 98. HEAVY-DUTY DIESEL AVERAGE POLYCYCLIC AROMATIC 

HYDROCARBONS IN EXHAUST AND LUBRICANTS ......................................... 210

 99. HEAVY-DUTY DIESEL AVERAGE ALKANES IN EXHAUST AND 

LUBRICANTS ................................................................................................................ 215

 100. HEAVY-DUTY DIESEL AVERAGE HOPANES AND STERANES IN 

EXHAUST AND LUBRICANTS .................................................................................. 216

 101. HEAVY-DUTY DIESEL AVERAGE ELEMENTAL CARBON AND 

ORGANIC CARBON RATE ........................................................................................ 216

 102. AVERAGE SULFATE EMISSIONS FROM HEAVY-DUTY DIESEL 

VEHICLES ..................................................................................................................... 217

 103. HEAVY-DUTY DIESEL VEHICLE AVERAGE SOLUBLE ORGANIC 

FRACTION ..................................................................................................................... 217

 104. REGULATED EMISSIONS AND FUEL ECONOMY FOR THE HEAVYDUTY DIESEL-FUELED VEHICLES ........................................................................ 224

 105. VARIATIONS IN ESTIMATED OIL CONSUMPTION RATES FOR THE 

HEAVY-DUTY DIESEL-FUELED VEHICLES ........................................................ 225

 106. TOTAL, ELEMENTAL, AND ORGANIC CARBON EMISSIONS ........................ 226

 107. CARBON AND OTHER ELEMENT TOTALS COMPARED TO TOTAL PM .... 227

 108. ESTIMATION OF UNBURNED OIL USING VARIOUS TRACERS .................... 227

 109. COMPARISON OF UNBURNED OIL ESTIMATES TO OC .................................. 228
xix 

ACKNOWLEDGEMENTS

Southwest Research Institute acknowledges the following sponsors of this project: 

• DOE Office of Vehicle Technologies (Dr. James Eberhardt, Chief Scientist) through the 

National Renewable Energy Laboratory 

• Coordinating Research Council; Project AVFL-14 

Anderson, W. D. (Doug) American Chemistry Council 

Ansari, Matthew Chevron Global Lubricants 

Ayala, Alberto California Air Resources Board

Bardasz, Ewa Lubrizol Corporation 

Cannella, Bill Chevron Energy Technology Co. 

Christianson, Michael U. S. Environmental Protection Agency 

Clark, Wendy National Renewable Energy Laboratory 

Collins, John California Air Resources Board

DiCicco, Dominic Ford Motor Company

Eng, King Shell Global Solutions (US) 

Evans, Joan Infineum USA

Fernandez, Frank Chevron Oronite Company 

Foster, Mike BP

Graves, Ronald L. Oak Ridge National Laboratory 

Huai, Tao California Air Resources Board

Impullitti, Joseph South Coast Air Quality Management District

Jetter, Jeff Honda R&D Americas Inc.

Johnson, Stuart Volkswagen of America 

Jorgensen, Scott General Motors R&D Center

Kastanien, Chris Lubrizol Corporation 

Kemp, Steven General Motors Powertrain

Kennedy, Steve ExxonMobil Research & Engineering 

King, Tracey Chrysler LLC

Knoll, Keith National Renewable Energy Laboratory 

Kowalski, Teri D. Toyota Technical Center

Kubsh, Joseph Manufacturers of Emission Controls Association (MECA)

Lawson, Douglas R. National Renewable Energy Laboratory 

Lax, David API

Mabutol, Andy Mitsubishi Motors R&D North America

McCormick, Robert National Renewable Energy Laboratory 

Mount, Jerry ConocoPhillips 

Mueller, Chuck Sandia National Laboratory 

Natarajan, Mani Marathon Oil Company 

Passut, Charlie Afton Chemical Corporation

Patterson, David Mitsubishi Motors R&D North America

Schleyer, Charles H. ExxonMobil Research & Engineering (retired)

Schneider, Eric General Motors R&D Center
ACKNOWLEDGEMENTS (CONT’D)

xx 

Smith, Dennis A. US Dept of Energy 

Smolenski, Don General Motors Corporation 

Stork, Kevin US Dept of Energy 

Teets, Michael Chrysler LLC

Thiele, Terry Lubrizol Corporation 

Thornton, Matthew National Renewable Energy Laboratory 

Tittel, Richard BP Lubricants Americas 

Torres, Sean Ford Motor Company

Valentine, Marie Toyota Technical Center

Wang, Jerry Chevron Oronite Company 

Watkins, Matt ExxonMobil Research & Engineering 

Webster, Leah Nissan Technical Center North America

Williams, Lewis Lubrizol Corporation 

Wright, Ken ConocoPhillips 

Zigler, Brad National Renewable Energy Laboratory 

• South Coast Air Quality Management District

• California Air Resources Board/California Energy Commission 

• The Lubrizol Corporation

• American Chemistry Council Product Approval Protocol Task Group (PAPTG) for 

providing the fresh and aged crankcase lubricants

• Mr. George Korbowski and Foothill Transit for the use of their natural gas buses 

• Mr. Jose Diaz and VIA Metropolitan Transit for the use of their diesel buses

Desert Research Institute and Elemental Analysis Inc. conducted chemical analyses under 

subcontract to SwRI.
xxi 

ACRONYMS AND ABBREVIATIONS

AACOG Alamo Area Council of Government

ACS American Chemical Society

API American Petroleum Institute

ASE Accelerated Solvent Extractor

ASTM American Society for Testing and Materials

B0 straight TxLED diesel fuel

B20 twenty percent bio-diesel blend with TxLED

BCF baseline crankcase flush

Btu British thermal unit

°C degrees Centigrade

C14H10 phenanthrene

C16H10 pyrene

C20H42 eicosane

C26H54 hexacosane

C36D74 hexatriacontane-d74

CH4 methane

CH2Cl2 dichloromethane

CLOSE Collaborative Lubricating Oil Study on Emissions

CNG compressed natural gas

CO carbon monoxide

CO2 carbon dioxide

CPS City Public Service Company (San Antonio)

CRC Coordinating Research Council

CS catalytic stripper

CVS constant volume sampling

DCM dichloromethane

DDC Detroit Diesel Corporation

DDW deionized-distilled water

DHA detailed hydrocarbon analysis

DPF diesel particulate filter

DR dilution ratio

DRI Desert Research Institute

DVPE dry vapor pressure equivalent

E10 gasoline containing 10 percent volume denatured ethanol

EC elemental carbon

EC/OC elemental carbon/organic carbon

EDXRF energy dispersive x-ray fluorescence

EEPS engine exhaust particle size

EGR exhaust gas recirculation

EI electron impact

EPA US Environmental Protection Agency

ERA Environmental Research Associates

°F degrees Fahrenheit

FBP final boiling point

FIA flame ionization analyzer

FID flame ionization detector

FTP Federal Test Procedure

g gram 
xxii 

ACRONYMS AND ABBREVIATIONS (CONT’D)

GC/MS gas chromatography/mass spectrometry

HC hydrocarbons

HD heavy-duty

HDCC heavy-duty chassis cycle

HDDC heavy-duty driving cycle

HD-D-NE heavy-duty diesel normal emitter

HE high (PM) emitter, or high mileage heavy-duty vehicle

HM high mileage vehicle

IBP initial boiling point

IC ion chromatograph

ICP-MS inductively coupled plasma-mass spectrometry

Kg kilogram

KHP potassium hydrogen phthalate

kPa kilopascal

lb pound mass

LD light-duty

LNG liquefied natural gas

LOC lubricating oil consumption

LPG liquified petroleum gas

MD medium-duty

mg milligram

MJ megajoule

mL milliliter

MON motor octane number

MOUDI micro orifice uniform deposit impactor

NABI North American Bus Industries

NE normal (PM) emitter

ng nanogram

NIST National Institute of Standards and Technology

NMHC non-methane hydrocarbon

NMOG non-methane organic gases

NOX oxides of nitrogen

NREL National Renewable Energy Laboratory

OC organic carbon

Orion Orion Bus Industries

PAH polynuclear aromatic hydrocarbon

PAPTG American Chemistry Council Product Approval Protocol Task Group

PDP positive displacement pump

PM particulate matter

PN particle number

PNA polynuclear aromatics

POC particle-phase organic compounds

ppm parts per million

psi pounds per square inch

QC quality control

RFP request for proposal

RON research octane number

RVP Reid vapor pressure

SCAQMD South Coast Air Quality Management District
xxiii 

ACRONYMS AND ABBREVIATIONS (CONT’D)

SFC supercritical fluid chromatography

SIS selective ion storage

S/N signal-to-noise

SOA soluble organic aerosol

SOF soluble organic fraction, percent

SPSS solid particle sampling system

SRM standard reference material

STN Speciation Trends Network

SVOC semi-volatile organic compounds

SwRI Southwest Research Institute

TC total carbon

TCEE temperature controlled emissions enclosure

THC total hydrocarbons

TIGF Teflon-impregnated glass-fiber filters

TOR thermal/optical reflectance

TOT thermal/optical transmittance

TxLED Texas low-emission diesel fuel (<15ppm sulfur) 

UCM unresolved complex mixture (alkanes)

UDC unified driving cycles

UDDS urban dynamometer driving schedule

μg microgram 

vol. volume

XRF x-ray fluorescence
xxiv 

EXECUTIVE SUMMARY

The Collaborative Lubricating Oil Study on Emissions (CLOSE) project was a pilot 

program to investigate methodologies to indicate how fuels and crankcase lubricants contribute 

to the formation of particulate matter (PM) and semi-volatile organic compounds (SVOC) in 

vehicle exhaust. It was conducted with a very limited number of vehicles, some of which did not 

have the latest engine and emission system technology, and no vehicles in this study were 

equipped with particle traps. The results of this study are not representative of the whole fleet of 

on-road vehicles. Long term lubricant effects on engine and aftertreatment were not investigated 

in this study.

Two vehicles from each of four categories were studied, for a total of eight test vehicles:

• Light-duty gasoline passenger cars,

• Medium-duty diesel pickup trucks, 

• Heavy-duty natural gas fueled transit buses, and 

• Heavy-duty diesel transit buses. 

Within each of the four vehicle categories, one normal PM emitting vehicle and one high 

PM emitting vehicle were selected. Each high emitter vehicle was to be selected on a criterion of 

consistent smoke visible in the tailpipe exhaust. While the high emitter natural gas-fueled 

heavy-duty vehicle did not exhibit white smoke, it was a higher-mileage vehicle than the normal 

PM emitter. Similarly, the high emitter heavy-duty diesel vehicle did not exhibit consistent 

visible white smoke, but it exhibited high oil consumption and high blowby. Because the HD 

natural gas and HD diesel vehicles designated HE did not exhibit higher PM emissions, they are 

designated as high mileage (HM). 

Vehicles were evaluated using the following fuels: 

• Light-duty vehicles:

o Non-ethanol containing gasoline (designated E0), and 

o 10 percent ethanol blend (designated E10) 

• Medium-duty vehicles: 

o Conventional low-sulfur TxLED diesel (designated D), and 

o 20 percent bio-diesel blend (designated B20) 

• Heavy-duty vehicles:

o Conventional low-sulfur TxLED diesel (designated D), or 

o Natural gas

With the light- and medium-duty vehicles, the effects of ambient temperature at 20°F and 

72°F on regulated and unregulated pollutant emission rates were also evaluated. With all the 

vehicles the effects of lubricating oil vintage (fresh and aged) on emission rates were evaluated. 
xxv 

All vehicle testing occurred on chassis dynamometers. Light- and medium-duty vehicles 

were operated over the California Unified Driving Cycle, while heavy-duty vehicles followed the 

Heavy Duty Urban Dynamometer Driving Schedule. The following exhaust emissions were 

determined: 

• Regulated gaseous emissions (HC, CO, NOX, CO2) 

• PM

o Mass emission rate (gravimetric)

o Elements (including lube oil markers)

 XRF

 ICP-MS for subset of 18 elements 

o Hopanes and steranes by GC/MS 

o “Elemental” and “organic” carbon by TOR/TOT

o PAHs by GC/MS

o C14 to C40 alkanes & cycloalkanes by GC/MS

o A deuterated alkane as a lube oil tracer by GC/MS (C36D74) 

o Soluble organic fraction by extraction 

o Sulfate by ion chromatography 

• Semi-volatile organic constituents by GC/MS

• Real-time particle count and size distribution by EEPS

o Total particles

o Solid particles only 

Chemical markers were utilized to estimate the lubricant contribution to PM, which was 

based on the following assumptions: 

• that the survival rate through the engine and catalyst was the same for a given 

marker as for the rest of the motor oil formulation components, and 

• that confounding of fuel and lube oil derived markers was negligible (i.e. that fuel 

contributions to the marker count are negligible compared to lubricant derived 

contributions). 

Potentially useful lubricant markers included oil additive metals, hopanes and steranes, 

and an unresolved complex mixture (UCM) of C20 to C35 alkanes and cycloalkanes. Additionally 

a deuterated alkane, n-hexatriacontane (C36D74), was added to the crankcase lubricant as a 

marker. Utilizing deuterated n-hexatriacontane tracer to estimate contributions of lubricants to 

exhaust particulate and SVOCs was not as successful as using the sum of hopanes and steranes 

or the unresolved complex mixture. However, none of these markers were consistently reliable 

for estimating engine oil consumption rates. Engine oil consumption could have been 

determined by physically measuring the loss of engine oil from the crankcase over a measured 

driving interval. This measurement was not done for the vehicles tested in this program with two 

exceptions – the light- and medium-duty high emitters. In two cases, the vehicle owner provided 

anecdotal oil consumption information. In hindsight, measurement of engine oil consumption 

rates would have been a valuable addition to the project. 

Any large scale quantitative underprediction of lubricant consumption rates by utilized 

markers likely means the lubricant-derived species levels assessed in the tailpipe streams were 

lost via deposition or conversion within the engine/exhaust or measurement systems. Markers 
xxvi 

which might survive the engine and catalyst any more or less than other lubricant components 

could also bias the quantitative allocation of the PM.

Polynuclear aromatic hydrocarbon (PAH) compounds were used as markers for fuel 

combustion products; however, for vehicles with normally-functioning exhaust catalysts, the 

PAH levels were too low for the measurement technique, and thus uncertain data were obtained. 

Normal emitters also have much higher ratios of fuel consumed to lubricant consumed compared 

to high emitters. The reduced certainty of the derived PM allocations from normal emitters may 

also be due to confounding of fuel and lubricant derived markers. In general, as indicators, 

PAHs accounted for less than one percent of organic carbon (OC) emitted.

Results of measurements showed that unburned crankcase lubricant made up 60 to 

90 percent of measured OC emissions from this small sample of on-road vehicles. These results 

were consistent across the four vehicle types and all fuels. This organic carbon represented 20 to 

50 percent of all emitted PM, except for the normal emitting light-duty gasoline passenger car

(OC was < 10 percent of PM) and the heavy-duty natural gas-fueled transit bus (OC was > 

90 percent of PM).

The OC fraction of PM for the four compression ignition diesel vehicles was less than for 

the two spark ignition natural gas buses and the high emitter spark ignition gasoline light duty 

passenger car. However, overall OC mass emissions rates for the four diesel vehicles were up to 

an order of magnitude higher than from the normal emitter spark ignition light duty gasolinefueled passenger car. The high PM emitter spark ignition vehicle had OC emissions rates 

comparable to the four diesel-powered vehicles. 

Normally-functioning three-way catalysts are effective at reducing most of the organic 

carbon. With high PM emitters or vehicles with deteriorated aftertreatment, high molecular 

weight fuel components and unburned lubricant were emitted at higher rates (one to two orders 

of magnitude) than in vehicles in proper engine repair and functioning emissions systems. In 

most cases, over 75 percent of lubricating oil components were combusted or converted across 

exhaust catalysts.

For the normally-operating light-duty gasoline and medium-duty diesel vehicles and for 

both heavy-duty natural gas vehicles, fresh oil produced more particles than aged oil. The 

opposite trend occurred with the light- and medium-duty high PM emitters. This effect was not 

readily apparent with the heavy-duty diesel vehicles. One explanation could be that, since the 

lubricant represented a much smaller fraction of the total PM (around 20 percent) in the HD 

diesel vehicles, the effect was lost in the precision of the testing methodology. 

In many cases, emitted PM was incompletely accounted for with chemical analyses. It is 

possible that some fraction of unburned and/or partially combusted fuel and oil, or some polar 

fraction of PM, was not measured with the analytical techniques used in this program.

Follow-up studies should assess the methods of PM allocations used in this study on 

vehicles representing the diverse spectrum between normal emitters and high emitters, and 

should estimate the precision of the allocations obtained by running multiple analyses. Vehicles 
xxvii 

should be tested with fuels without hopanes and steranes in order to help clarify the potential 

confounding (or lack thereof) when markers are parented by both fuel and lubricant. Studies 

should be conducted to understand the relative frequency of various types and intensities of ‘high 

emitters’ to facilitate modeling of the on-road vehicle fleet.

Future work could consider testing emissions from diesel vehicles equipped with 

normally-functioning particle filters to determine if this type of aftertreatment system produces 

similar results. Also, it would be informative to utilize the latest engine and emissions system 

hardware for all the vehicles to determine if the considerable efforts by regulators and OEMs 

have impacted PM levels. Noting that aged lubricants sometimes produce less PM than fresh oil, 

it would be interesting to investigate the effects of base oil volatility and type (i.e., mineral-based 

versus synthetic) on PM and SVOC formation. 
xxviii 

SUMMARY OF MAJOR TECHNICAL FINDINGS

LIGHT-DUTY GASOLINE VEHICLE TESTS

Fresh and Aged Oil

• Normal PM emitter: PM nominally* increased in three of four configurations with aged oil. 

• High PM emitter: PM nominally decreased with aged oil. 

E0 and E10 Fuel

• Normal PM emitter: PM nominally increased with E10.

• High PM emitter: no trend was apparent.

Normal and High PM Emitters

• High PM emitter produced much higher rates of all emissions compared to low emitters. 

Normal (72°F) and Low (20°F) Temperatures

• Normal PM emitter: PM nominally increased during cold starts.

• High PM emitter: PM nominally decreased during cold starts.

• The lack of PM response to temperature from the HE vehicle is an important finding 

relevant to modeling fleet emissions. Because high emitters contribute disproportionately, 

the temperature effects across a full range of moderate to high emitter vehicles should be 

studied to ensure accurate modeling of the fleet. 

Particle Number and Particle Size Distributions

Particle Number (PN) Emissions 

• Normal PM emitter:

• The combination of cold start and cold ambient temperature operation resulted in the 

highest PN emissions. 

• Fresh oil emitted higher number of solid and volatile particulates compared to emissions 

from aged oil. 

• E10 resulted in higher particulate emissions compared to E0 at 72°F. 

• At 20°F there was not a consistent trend between E0 and E10. 

• Greater than 70% of the particles emitted were solid. 

• High PM emitter:

• The highest PN concentrations were observed with the high emitter. 

• Emissions were dominated by volatile particles. 

Particle Size Distribution

• The total and solid distributions exhibit similar bimodal lognormal structure that consists of a 

nuclei mode <20 nm, and an accumulation mode. 

• For fresh oil, the accumulation mode peaked at about 50 to 60 nm and the nuclei mode 

peaked at 10 nm. 

_____________ 

* The terms ‘nominal’ and ‘nominally’ are used throughout this report to indicate a lack of statistical rigueur to the 

data discussed.
xxix 

LIGHT-DUTY GASOLINE VEHICLE TESTS (CONT’D)

• For aged oil, the accumulation mode was lower than that for fresh oil in concentration and it 

was at least 20 nm smaller in diameter than that of the fresh oil. 

• For high emitters, the accumulation mode is volatile in nature. 

• For normal emitters, the accumulation mode is composed of solid particles. 

PM Apportionment

• Normal PM emitter: While the presence of elemental tracers and UCM alkanes indicates 

some contribution of oil to the exhaust PM, the relative fuel and lubricant contributions are 

uncertain due to low emissions levels. 

• High PM emitter: Nearly all of the exhaust PM is associated with the lubricating oil. 
xxx 

MEDIUM-DUTY DIESEL VEHICLE TESTS

Fresh and Aged Oil

• Normal emitter (NE) vehicle: PM emissions nominally decreased with aged oil. 

• High emitter (HE) vehicle: PM emissions nominally increased with aged oil. 

Neat Diesel (B0) and Twenty Percent Biodiesel (B20)

• Normal emitter (NE) vehicle: No effect of B20. 

• High emitter (HE) vehicle: PM nominally increased for B20. 

Normal (72°F) and Low (20°F) Temperatures

• Normal emitter (NE) vehicle: At low temp., PM nominally increased. 

• High emitter (HE) vehicle: At low temp., PM nominally decreased. 

Particle Number and Particle Size Distributions

Particle Number (PN) Emissions

• Normal emitter (NE) vehicle: 

• Fresh oil emitted more solid and volatile particles than aged oil. 

• B20 resulted in lower solid and volatile emissions (15% to 20%) than B0. 

• No major differences between normal/low temp. and cold-start/hot-start portions of the 

cycle. 

• Solid PN ranged from 50% to 83% of the total emissions (volatile PN range 50% to 

37%). 

• High emitter (HE) vehicle: 

• Aged oil emitted more solid particles than fresh oil. 

• No consistent trend observed between B0 and B20. 

• No major differences between normal/low temp. and cold-start/hot-start portions of the 

cycle. 

• Solid PN accounted for 26% to 65% of the total emissions (volatile PN range 74% to 

35%). 

Particle Size Distribution

• For both NE and HE vehicles, solid PM distributions exhibited monomodal lognormal 

distribution structure with accumulation mode peak between 50-70 nm. 

• For both NE and HE vehicles, total PM distribution exhibited bimodal lognormal distribution 

structure with a volatile nuclei mode peak between 10-20 nm. 

• More pronounced volatile mode was observed at low temperature and in a HE vehicle. 

PM Apportionment

• Normal emitter (NE) vehicle: 

• No real vehicle oil consumption rate was measured; estimated oil consumption rate was 

0.16 quarts/1000 miles. 

• Tracer and hopanes/sterane totals were used to estimate unburned oil emission rates that 

were similar to organic carbon measurements. 

• Total carbon emission rates were similar to measured values. 

• Carbon fraction from unburned oil was estimated to be 83% of measured organic carbon. 
xxxi 

MEDIUM-DUTY DIESEL VEHICLE TESTS (CONT’D)

• High emitter (HE) vehicle: 

• Measured and estimated oil consumption rates matched and were found to be 0.49 

quarts/1000 miles. 

• Total carbon emission rates did not correlate with measured values. 

• Variations in PM composition were obtained for different sampling protocols. 
xxxii 

HEAVY-DUTY NATURAL GAS VEHICLE TESTS

Fresh and Aged Oil

• Normal PM emitter and High Mileage (HM) vehicle: PM nominally decreased on aged oil. 

Fuel

• Only natural gas was used as a fuel. 

Normal and High Mileage PM (HM) Emitter

• No trend in PM was evident between the normal and high mileage vehicles. PM emissions 

ranged from 14 to 22 mg/mi. 

Normal (72°F) and Low (20°F) Temperatures

• No low temperature tests performed. 

Particle Number and Particle Size Distributions

Particle Number (PN) Emissions

• Normal PM emitter:

• More PN emissions were observed during the hot-start portion of the cycle compared to 

the cold start. 

• Fresh oil nominally increased PN emissions compared to used oil. 

• 25 to 55% of the number of particles emitted were solid in nature. 

• High mileage vehicle: 

• >80% of the PM were volatile particles. 

• Fresh oil nominally increased PN emissions as compared to used oil. 

Particle Size Distribution

• For the normal emitter with both fresh and used oil, the total and solid distributions seem to 

exhibit monomodal lognormal size distribution structures that consists of a nuclei mode. The 

nuclei peaks at 10 nm. 

• Similar size distribution was observed with the high mileage vehicle. 

PM Apportionment

• Estimated (calculated) oil consumption rates varied considerably when determined by 

different methods. 

• Several parameters indicate the catalyst in the normal emitter may be more active than in the 

high mileage vehicle. 

• Oil consumption rate may indicate that 99% of the consumed oil is burned or partially burned 

in the combustion chamber or in the vehicle catalyst system for the normal emitter, while 95 

to 98% of the consumed oil was burned or partially burned for the high mileage vehicle. 

• Both vehicles had similar PM emissions rates, but the makeup of the PM was very different. 

The high mileage vehicle PM consisted of nearly 80% organic material while the normal 

emitter consisted of 40% organic material. 
xxxiii 

HEAVY-DUTY DIESEL VEHICLE TESTS

Fresh and Aged Oil

• Normal emitter (NE) & High mileage (HM) vehicle: PM emissions were lower for aged oil. 

Neat Diesel (B0) and Twenty Percent Biodiesel (B20)

• Only B0 tested. 

Normal (72°F) and Low (20°F) Temperatures

• No low temperature tests performed. 

Particle Number and Particle Size Distributions

Particle Number (PN) Emissions

• Normal emitter (NE) vehicle: 

• No major differences between normal/low temp. and cold-start/hot-start portions of the 

cycle. 

• Solid PN ranged from 70% to 90% of the total emissions (volatile PN range 30% to 

10%). 

• High mileage (HM) vehicle: 

• Solid PN accounted for over 70% of the total emissions (volatile PN range less than 

30%). 

Particle Size Distribution

• No notable differences observed between fresh/ aged oils, cold/hot start and NE/HM 

vehicles. 

• Total and solid PM distributions exhibited monomodal lognormal distribution structure with 

accumulation mode peak between 50 – 70 nm. 

PM Apportionment

• No real vehicle oil consumption rates were measured. 

• Estimated (calculated) oil consumption rates varied considerably when determined by 

different methods. 

• Normal emitter (NE) vehicle: Carbon fraction from unburned oil was estimated to be 89% of 

measured organic carbon. 

• High mileage (HM) vehicle: 

• Carbon fraction from unburned oil was estimated to be 62% of measured organic carbon. 

• PAH emission rates were higher than NE. 
1 

1.0 INTRODUCTION

Despite significant recent legislative controls, particulate matter (PM) remains an 

important contributor to urban air quality, and internal combustion engine emissions are among 

the most significant contributors to ambient fine PM levels.

1,2 Technological developments in 

the area of in-cylinder PM control and the use of high-efficiency catalytic aftertreatment 

technologies will provide tremendous benefits when engines/vehicles employing these 

approaches become pervasive in the marketplace. But, given the relatively long life of vehicles, 

in both the light-duty and heavy-duty market, a significant fraction of older, higher-polluting 

vehicles will remain on the road for many years. In fact, a growing body of evidence is 

suggesting that these older, often poorly maintained vehicles contribute disproportionately to 

pollutant inventories.3,4,5,6

There are a number of contributing factors that determine the rate of production and the 

chemical nature of PM emissions including engine design and control measures, fuel and 

lubricant properties, and duty cycle. Improved power cylinder design, higher pressure fuel 

injection, and more recently, the introduction of high-efficiency particle filtration technologies 

have enabled significant reductions in the mass rate of PM emissions from new engines.7 Fuel 

sulfur regulations were first implemented in the early 1990s and are being phased in here in the 

United States and around the world in an effort to reduce sulfate-derived PM emissions and to 

enable the aforementioned catalytic aftertreatment technologies.

Engine lubricating oil has also been implicated as a significant parent material in the 

formation of mobile source PM emissions, including nanoparticle emissions. This is true of both 

compression and spark-ignited engines independent of fuel source. Studies have shown that 

high-emitting engines (oil burners) are the most toxic in terms of potency per unit mass of 

emissions.

8, 9, 10

However, to date much of the present understanding regarding the impact of lubricating 

oil on PM emissions has been anecdotal and not the subject of a focused and carefully conducted 

research study. Recognizing this knowledge gap and the potential benefits to air quality and 

human health, the U.S. Department of Energy Office of Vehicle Technologies through the 

National Renewable Energy Laboratory (NREL), and the Project Management Team which 

included the South Coast Air Quality Management District (SCAQMD), the California Air 

Resources Board (CARB), the Coordinating Research Council (CRC), with support and advice 

from the American Chemistry Council Product Approval Protocol Task Group (PAPTG), sought 

to characterize PM emissions from in-use low and high PM emissions vehicles. 

A single high-emitting vehicle was chosen in each vehicle type to be a very high PM 

emitter with evidence of oil consumption or visible consistent white smoke, and each vehicle 

was expected to be near the end of its useful life. Additionally, allocation estimates on the 

normal emitter vehicle in each vehicle type are generally less precise than for high emitters. Thus 

results from this pilot study cannot be presumed to accurately represent the wide variety of onroad vehicles of various life stages and maintenance histories.
2 

2.0 OBJECTIVE

The U.S. Environmental Protection Agency (EPA) revised the National Ambient Air 

Quality Standards (NAAQS) for PM10 and PM2.5 in October 2006, revoking the annual PM10 

standard and lowering the 24-hour PM2.5 standard to 35 μg/m3. The existing annual 24-hour 

standards for PM10 and PM2.5 (150 μg/m3 and 15 μg/m3

, respectively) were retained. Control 

plans for the 2006 standards are to be submitted to EPA in the 2012-13 timeframe for areas that 

are in nonattainment. In preparing these plans, State and local agencies are using emissions 

models and chemical transport models to identify and evaluate potential emission reduction 

measures.

While predictions of PM concentrations have been reasonably accurate for sulfates and 

nitrates, model performance for particulate organic matter has been generally poor (Kleeman and 

Cass, 2001).11 According to official government inventories, mobile sources currently account 

for a third of the directly emitted PM2.5 emissions in California’s South Coast Air Basin 

(SoCAB) with gasoline-powered vehicles accounting for less than 10% (CARB, 2008).12 

However, model predictions have shown that gasoline-powered vehicles may account for 60% of 

the total predicted secondary organic aerosols (SOA) in the SoCAB during summer (Kleeman et 

al., 2007).13 Furthermore, model results have under-predicted observed carbon concentrations by 

about 50% suggesting either the presence of an unknown or underestimated source of primary 

organic aerosol or that more SOA is being formed than is accounted for by current models (Ying 

and Kleeman, 2007).14

To supplement current knowledge of particulate emissions from mobile sources, and to 

investigate methods to identify the sources of compounds which make up particulate, the CLOSE 

project was undertaken with support from Federal, State, and local government agencies and 

industry The objective of this project was to conduct chemical and physical characterizations of 

particulate matter (PM) emissions from a limited number of vehicles fueled with gasoline, E10, 

diesel, biodiesel, and natural gas while operating on fresh and used crankcase lubricants in an 

effort to investigate methodologies to indicate how fuels and crankcase lubricants contribute to 

the formation of PM and semi-volatile organic compound (SVOC) emissions in vehicle exhaust. 
3 

3.0 SCOPE OF WORK

This project was initiated to characterize particulate matter (PM) emissions from four 

vehicle types operating on multiple fuels and lubricants at two test temperatures. The four 

vehicle types studied were: light-duty gasoline passenger cars, medium-duty diesel trucks, 

heavy-duty natural gas fueled transit buses, and heavy-duty diesel transit buses. Two vehicles of 

each vehicle type were selected and studied: one normal PM emitting vehicle and one high PM

emitting (or high mileage) vehicle. PM characterizations were carried out to investigate whether 

the relative contribution of lubricant to particulate could be estimated, and whether the lubricant 

contribution to PM changed with different fuels and lubricant compositions. 

This report covers emission testing of in-use light-duty and medium-duty vehicles with 

both normal and high rates of particulate emissions. Low- and high-mileage in-use heavy-duty 

vehicles were also tested with the expectation that the high-mileage vehicles would produce 

higher PM emissions. Light-duty vehicles were tested with regular (non-oxygenated) gasoline 

and ten percent ethanol fuel blends. Medium-duty vehicles were tested with both straight diesel 

and a twenty percent bio-diesel blend. Heavy-duty vehicles were tested with natural gas and 

straight diesel fuels. Light-duty and medium-duty vehicles were tested at room temperature

(72°F) and 20°F. Heavy-duty vehicles were tested only at room temperature. All vehicles were 

tested with both fresh and aged lubricants. 

 Light-duty and medium-duty vehicles were tested over replicate cold-start Unified 

Driving Cycles (UDC). Thus, only one UDC per day was run. The UDCs were conducted as a 

cold-start, four-phase test, in a manner similar to the light-duty Federal Test Procedure. Heavyduty vehicles were evaluated over the EPA Urban Dynamometer Driving Schedule (UDDS) for 

Heavy-Duty Vehicles. The heavy-duty UDDS is also known as the Heavy-Duty Chassis Cycle 

(HDCC). Heavy-duty vehicles were operated over a series of cold- and hot-start tests conducted 

on the same day. Only short-term effects were investigated in this study. Lubricants could have 

long-term effects on exhaust emissions which differ from the short-term effects.

A summary of the complete project test matrix, tunnel blank or background sampling 

schedule, and tunnel cleaning and conditioning events is presented in Table 1. Because the HD 

natural gas and HD diesel vehicles designated HE did not exhibit higher PM emissions, they are 

sometimes designated as high mileage (HM). 

Each emission test performed during the course of the project was given an individual 

test name and number according to the coding shown in Table 2. Acronyms were used to denote 

type of vehicle (LD, MD and HD), PM emission rate (normal or high), lubricant type (fresh or 

aged), fuel type, ambient test temperature, replicate test number, and sub-test letter (for multiple 

tests to capture PM mass). Project details are presented in the following sections.

SwRI’s criteria for selecting high-emitting vehicles were not based on make, model, type 

of owner, mileage, or any other a priori assumptions regarding the likelihood of any specific 

type of vehicle being a good candidate. With decades of emission regulations in place, and 

manufacturers producing extremely durable engine and exhaust control systems, SwRI 

recognizes that ‘smoking’ vehicles are not the norm in the existing fleet of operational vehicles; 

therefore, any vehicle selected is atypical.
4 

TABLE 1. PROJECT TEST MATRIX

TEST TEMPERATURE 72°F 20°F

TEST LUBRICANT FRESH FRESH AGED AGED FRESH FRESH AGED AGED

SAMPLE 1 2 1 2 1 2 1 2

Clean and condition Light-Duty tunnel. Collect tunnel blank.

LD E0 gasoline 

(Normal PM Emitter)

No. of tests1 8 8 8 8 2 2 2 2 

No. of miles2 158 158 158 158 39 39 39 39

Background X X X X X X X X

Condition Light-Duty tunnel. Collect tunnel blank.

LD E10 gasoline 

(Normal PM Emitter)

No. of tests 8 8 8 8 2 2 2 2

No. of miles 158 158 158 158 39 39 39 39

Background X X X X X X X X

Condition Light-Duty tunnel. Collect tunnel blank.

LD E0 gasoline (High 

PM Emitter)

No. of tests 1 1 1 1 1 1 1 1

No. of miles 19.7 19.7 19.7 19.7 19.7 19.7 19.7 19.7

Background X X X X X X X X

Condition Light-Duty tunnel. Collect tunnel blank.

LD E10 gasoline (High 

PM Emitter)

No. of tests 1 1 1 1 1 1 1 1

No. of miles 19.7 19.7 19.7 19.7 19.7 19.7 19.7 19.7

Background X X X X X X X X

Clean and condition Medium-Duty tunnel. Collect tunnel blank.

MD diesel (Normal PM 

Emitter)

No. of tests 1 1 1 1 1 1 1 1 

No. of miles2 19.7 19.7 19.7 19.7 19.7 19.7 19.7 19.7

Background X X X X X X X X

Condition Medium-Duty tunnel. Collect tunnel blank.

MD B20 (Normal PM 

Emitter)

No. of tests 1 1 1 1 1 1 1 1

No. of miles 19.7 19.7 19.7 19.7 19.7 19.7 19.7 19.7

Background X X X X X X X X

Condition Medium-Duty tunnel. Collect tunnel blank.

MD diesel (High PM 

Emitter)

No. of tests 1 1 1 1 1 1 1 1

No. of miles 19.7 19.7 19.7 19.7 19.7 19.7 19.7 19.7

Background X X X X X X X X

Condition Medium-Duty tunnel. Collect tunnel blank.

MD B20 oxygenated 

diesel (High PM 

Emitter)

No. of tests 1 1 1 1 1 1 1 1

No. of miles 19.7 19.7 19.7 19.7 19.7 19.7 19.7 19.7 

Background X X X X X X X X

Condition Heavy-Duty tunnel. Collect tunnel blank.

HD natural gas 

(Normal PM Emitter)

No. of tests 6 6 6 6

No. of miles3 34 34 34 34

Background X X X X

Condition Heavy-Duty tunnel. Collect tunnel blank.

HD natural gas (High 

PM Emitter)

No. of tests 6 6 6 6

 

No. of miles 34 34 34 34

Background X X X X

Condition Heavy-Duty tunnel. Collect tunnel blank.

HD diesel (Normal PM 

Emitter)

No. of tests 2 2 2 2

No. of miles 11 11 11 11

Background X X X X

Condition Heavy-Duty tunnel. Collect tunnel blank.

HD diesel (High PM 

Emitter)

No. of tests 2 2 2 2

No. of miles 11 11 11 11

Background X X X X 1 Number of test runs with one set of filters in order to sample enough PM for later analyses. When only two tests were run, then a 

third test was run without a complete filter set just to measure particle number and size. (Section 6.3, Table 15) 2 LD, MD Driving Cycle: California Unified Cycle (19.7 miles per test, Section 7.4.1) 3 HD Driving Cycle: EPA HD Urban Dynamometer Driving Schedule (5.6 miles per test, Section 9.4.1) 
5 

TABLE 2. CLOSE PROJECT TEST CODES

Type of Vehicle PM Code1

Lubricant 

Code2 Fuel Code

Run ambient 

temperature3

Test 

Number4

Sample 

run5

LD = light-duty vehicle

NE = normal PM 

emitter F = fresh oil

E0 = nonoxygenated gasoline 72 = nominal 72F 1, 2, 3....A, B, 

C....

MD = medium-duty 

vehicle HE = high PM emitter A = aged oil

E10 = gasoline with 

10% ethanol 20 = nominal 20F 

HD = heavy-duty vehicle HM = high mileage D = diesel

 

B20 = diesel with 

20% bio-diesel 

NG = natural gas

1 PM Code

A normal PM emitter is a vehicle in good working order that consumes its oil at a normal rate. A high 

PM emitter is a vehicle that consumes its oil at a higher than normal rate, thus producing PM at a 

higher rate. 

2 Lubricant Code

Both fresh and aged oil are added to the engine after a flushing procedure, and then the vehicle is 

operated over 150 highway miles. Fresh oil has not been used in an engine, aged oil has been aged in 

fleet service then collected. 3 Run ambient 

temperature Ambient temperature is the soak space temperature for the vehicle.

4 Test Number

Two replicate tests are run in each configuration, but multiple samples (over multiple test cycles) are 

collected onto single filters in order to deposit enough PM for analyses.

5 Sample run

Each letter represents a test cycle run. For LD and MD vehicles each test cycle is one cold plus one 

hot Unified Driving Cycle (UDC). For HD vehicles each test cycle is one Heavy-Duty Driving Cycle 

(HDDC). One cold HDDC for each day's start and then multiple hot-start test cycles are performed.

Example: MD-NE-A-B20-20-2C is the Medium duty, normal PM-emitting vehicle filled with aged oil, operated on 20% 

biodiesel, with the soak temperature at a nominal 20F, during its second replicate test over the third cold/hot UDC.
6 

4.0 CLOSE PM SOURCE DETERMINATION APPROACH

Southwest Research Institute (SwRI) and Desert Research Institute (DRI) teamed to 

investigate the sources of PM using the PM, fuels, and lubricants analyses from DRI. Dr. Eric 

Fujita of DRI took the lead with the light-duty vehicle tests and produced a spreadsheet to review 

DRI’s results. SwRI then used Dr. Fujita’s spreadsheet as a template to input the medium- and 

heavy-duty analyses results and Dr. Lawrence Smith of SwRI reviewed those sets of data. The

approach is discussed below:

SwRI and DRI compared fuel and oil speciation results to look for unique compounds 

that could serve as possible tracers for either fuel or oil. We started with a lubricant tracer 

(deuterated hexatriacontane, C36D74) which was blended into each engine’s fresh and aged oil 

fills. The mass and mass fractions of the tracer in oil samples taken from the engines were

measured. In addition, the mass of tracer was measured from the exhaust PM captured during 

testing. The mass of PM associated with oil was calculated by ratioing the mass of tracer found 

in the exhaust PM to the mass fraction of tracer found in the oil. However, there is the 

possibility that some of the tracer could crack or oxidize when it was exposed to heat during incylinder and post-exhaust combustion, thus biasing these results. 

SwRI and DRI also analyzed both the lubricants and fuels for elements, and identified

those elements that were unique to oil. These elements likely come from additive packages that 

include Zn, P, Mg, and Ca. The collected exhaust PM samples were also analyzed for elements. 

The PM lubricant ratios of elements were compared to the ratios from the tracer analyses. The 

results of these two types of analyses (tracer and elements) indicated the contributions of burned 

versus unburned lubricant contribution. The rates of oil consumption were estimated from the 

exhaust emissions of tracers and corresponding abundances in lubricating oil. 

We also reviewed the results of hopanes, steranes and alkanes speciation for both fuels 

and lubricants and searched for hopanes/steranes that were unique to either fuel or oil. 

• There were hopanes/steranes found in some test fuels used in the emission tests; DRI 

analyzed fuels they collected in the Reno, NV area to check for similar results.

• For oils, we examined compounds with boiling points that are halfway between fuel 

and oil crossover and the end point of speciation. 

• For fuels, we searched for fuel-unique compounds with high boiling points, near (or 

in) the fuel and oil crossover range of their speciations. 

We also analyzed fuels, lubricants, and PM for PAHs, but like alkanes, these are not 

necessarily good tracers for lubricants. We searched for compounds that were present in each 

lubricant that were not in the fuel. 

Each unique compound or element could be used to calculate a range of potential 

fractions of fuel or lubricant contribution to PM. We followed this approach for each fuel and 

lubricant combination. 

Regarding the continuous particle sizing and counting being performed during each test, 

we hypothesized that the solid particle number in the sub-20 nanometer size range was lube-oil 

related, mainly due to metallic ash.
7 

5.0 LUBRICANTS AND FUELS

5.1 Lubricants

Two different crankcase lubricant conditions, fresh and aged, were evaluated during this 

test program. When changing crankcase lubricants, a drain and fill operation was first performed 

to install detergent flush oil–baseline crankcase flush (BCF) oil–which is used in the ASTM 

Sequence VIB procedure. Following this, a flush procedure was conducted to install each test 

lubricant in the crankcase. The lubricant flush and fill sequence was as follows:

1. Idle the engine for a minimum of 15 minutes and until the engine oil sump 

temperature reaches 150°F.

2. Drain the engine oil and fill with BCF flush oil. 

3. Idle the engine for a minimum of 15 minutes. 

4. Drain the engine flush oil and fill with the test oil (first fill).

5. Idle the engine for a minimum of 15 minutes. 

6. Drain the test oil and fill with the test oil (second fill).

7. Idle the engine for a minimum of 15 minutes.

8. Drain the test oil and fill with the test oil (third fill).

Following the final fill, each lubricant was degreened over approximately 150 vehicle

miles of operation. Items that influence oil shear stability include manufacturer, viscosity grade, 

engine conditions, and fuel dilution, among others. Although SwRI cannot predict how stable a 

crankcase lubricant might be in this test program, it is thought that this amount of operation was 

sufficient. Crankcase lubricant samples were collected at the end of each series of tests for 

analyses.

5.1.1 Description and Analyses

Lubricants were supplied by members of the American Chemistry Council on the 

Petroleum Panel Product Approval Protocol Task Group (PAPTG). Table 3 describes the 

lubricants used for all emission tests in this project. Table 4 shows the results from the supplier 

of analyses of the light-duty lubricants. Table 5 provides results from the supplier of analyses of 

the medium-duty lubricants. Table 6 shows the results from the supplier of analyses of the 

heavy-duty natural gas engine lubricants. Table 7 shows a summary of the lubricants used for 

heavy-duty vehicle testing. All lubricants were further analyzed by Desert Research Institute 

once they were used for emissions tests, and those results are included with the results of the 

associated emission tests.
8 

TABLE 3. PROJECT LUBRICANTS SUPPLIED BY AMERICAN CHEMISTRY COUNCIL 

MEMBERS

Lubricant 

Type

Light-Duty 

Gasoline & 

Ethanol Blends

Medium-Duty 

Diesel

Heavy-Duty 

Natural Gas Heavy-Duty Diesel

Performance 

Level

APISM/ILSAC 

GF-4 API CJ-4

Cummins CES20074 

/ DDC 7SE272 API CJ-4/SM

Viscosity 

Grade GF-4 5W20 15W40 15W40 15W40

How Aged Oil 

was Generated

2.7L to 4.6L Detroit 

OEM vehicles. 

Drain Interval 7.5K 

miles and 10K 

miles.

Heavy-Duty Mack 

Class 8 trucks over 

the road 80,000 lb 

max. Drain 

intervals 20,000 - 

30,000 miles.

Natural Gas City Bus 

Service, approx. 

60,000 miles/yr. 

6,000 mile drain 

interval. Engines 

were DDC Series 

50s and John Deere 

Natural Gas.

HD diesel line 

service running 

50% of the time at 

80,000 pound 

GVW. Drain 

interval was 25,000 

miles. Engines were 

2006 CAT C-15s 

and Cummins ISX.

SwRI Fresh 

Oil Code LO-221459 LO-223289 LO-223360 LO-245408

SwRI Aged 

Oil Code LO-223292 LO-223290 LO-223291 LO-244136

Supplier Infineum Afton Oronite Lubrizol

Supplier Code Infineum Gold RBR-010570-A-1 RPN GEO 15-40

Fresh OS218004AL 

Aged OS226608
9 

TABLE 4. LIGHT-DUTY OIL ANALYSES FROM SUPPLIER

SwRI Oil Code LO-221459 LO-223292

Property Measured Test Method a Fresh Oil Aged Oil

Additive Metals

Ca, % mass ASTM D4951 0.1974 0.213

Mg, % mass ASTM D4951 0.0015 0.0016

Mo, % mass ASTM D4951 0.0075 0.008

P, % mass ASTM D4951 0.0749 0.0676

Si, % mass ASTM 2622 0.0003 0.0011

Na, % mass ASTM D4951 0.0002 0.0005

Zn, % mass ASTM D4951 0.0852 0.0818

Wear Metals

Cu, ppm ASTM D4951 0 16

Pb, ppm ASTM D4951 0 0

Sn, ppm ASTM D4951 3 0

Al, ppm ASTM D4951 2 7

Fe, ppm ASTM D4951 2 9

TBN, mg/KOH/g ASTM D4739 9.4 9.9

TAN, mg/KOH/g ASTM D664 1.9 2.21

IR for Oxidation, absorbance/cm 0 13

IR for Nitration, absorbance/cm 0 21

Fuel Dilution 0 0

kV@100oC, cSt 8.5 8.38

kV@40oC, cSt 48 49

CCS @-30oC, cP D5293 6400 7010

MRV @-35oC, cP D4684 21300/NYS 26700/NYS

Water, % 0 0

Pentane Insolubles D893B N/A 0.06

Sulfur, mg/gram (ppm) b ICP-MS 2157 2160 a Analysis performed by Intertek

b Analysis performed by Elemental Analysis, Inc.
10 

TABLE 5. MEDIUM-DUTY OIL ANALYSES FROM SUPPLIER

SwRI Oil Code LO-221459 LO-223292

Property Measured Fresh Oil Aged Oil

Additive Metals, ppm

Boron 432 223

Calcium 1860 1960

Phosphorus 1069 1110

Zinc 1230 1300

Wear Metals, ppm

Copper x 6

Lead x 6

Tin x nil

Aluminum x 5

Iron x 29

TBN, D 4739, mg/KOH/g 7.8 3.7

TAN D 664, mg/KOH/g 4.9 3.5

IR for Oxidation, absorbance/cm x 11.03

IR for Nitration, absorbance/cm x 4.0

TGA Soot, % x 1.2

Fuel Dilution,% x 0.27

kV @ 100oC, cSt 14.97 14.58

kV @ 40oC, cSt 117.2 119.8

CCS @ -20oC, cP 6018 x

MRV @ -25oC, cP x 29561

Yield Stress x 0

Water, ppm x 242

x Not reported by supplier
11 

TABLE 6. HEAVY-DUTY NATURAL GAS OIL ANALYSES FROM SUPPLIER

 SwRI Oil Code LO-223360 LO-223291 
12 

TABLE 7. HEAVY-DUTY DIESEL OIL ANALYSES FROM SUPPLIER

SwRI Oil Code LO-245408 LO-244136

Measured Method Fresh Oil Aged Oil

Calcium, % ASTM D-5185, Elemental Analysis (ICP) 0.2191 0.2304

Boron, % " <0.001 0.0004

Barium, % " <0.001 <0.001

Copper, % " <0.001 0.0004

Chromium, % " 0 0.0003

Iron, % " 0 0.0044

Lead, % " 0 0.0006

Phosphorus, % " 0.1043 0.0997

Sulfur, % " 0.3322 0.3414

Silicon, % " <0.001 0.0005

Zinc, % " 0.1181 0.1182

TBN mg KOH/g ASTM D2896 8.1 6.7

TBN mg KOH/g ASTM 4739 8.36 7.6

Viscosity @ 100oC cSt ASTM D445_100 16.11 13.82

TGA Soot Test, % x 1.47 x Not reported by supplier

5.1.2 Hexatriacontane Tracer 

Deuterated n-hexatriacontane (n-C36D74) was to be mixed into the test lubricants at a rate 

of approximately 7.35 gram/gallon, to be used as a tracer in determining lube oil contribution to 

exhaust particulate and SVOCs. A recommended n-hexatriacontane blending procedure was 

obtained from the University of Washington and is shown in Appendix A.

The tracer was utilized to compare its concentration in the collected exhaust PM to the 

concentration in the oil. The proposed concentration blend for the oil was 7.35 g hexatriacontane 

per gallon of oil, but during the light-duty tests the blended concentration was 7.35 g tracer per 

quart of oil. The incorrect blend concentration was used for all the light-duty tests. Beginning 

with the medium-duty tests, and including the heavy-duty tests, the concentration was correctly 

blended to 7.35 g tracer per gallon of oil. 
13 

5.2 Fuels

5.2.1 Light-Duty Vehicles Fuels

Due to the participation of SCAQMD and CARB in the CLOSE project, there was a 

desire to evaluate the light-duty vehicles on a gasoline resembling California Phase 3 

reformulated gasoline. SwRI was able to locate a fuel with properties similar to California Phase 

3 fuel; except that the fuel was not oxygenated. For testing on E10, a California Phase 3 

certification fuel was procured and splash-blended with ethanol to bring the ethanol content up to 

10 volume percent. For testing at 20°F, SwRI used Cold CO test fuel; neat for E0 gasoline and 

splash-blended with ethanol for E10. 

Table 8 shows a summary of the fuels used for light-duty vehicle testing. Table 9 shows 

the analyzed results of the light-duty fuels. Further analyses of the fuels were performed by 

Desert Research Institute and those results are included in the emission test results section. Two 

Cold CO fuels were used for testing because the first batch of fuel was discarded inadvertently. 

A discussion of the two Cold CO fuels is given in the next section. 

TABLE 8. SUMMARY OF FUELS FOR LIGHT-DUTY VEHICLES

FUEL REGULAR E0 COLD CO 

E0 E10 COLD E10 NEW COLD CO 

E0

NEW COLD CO 

E10

SwRI Fuel Code EM-6314-F EM-5574-F EM-6391-F EM-6378-F EM-6802-F EM-6856-F

H/C ratio 1.884 1.879 1.879 1.849 1.828 1.902

Carbon fraction 0.863 0.864 0.833 0.834 0.867 0.831

Hydrogen fraction 0.136 0.136 0.131 0.129 0.133 0.133

Oxygen fraction 0.035 0.036 0.037

Density, lb/gal 6.102 6.109 6.130 6.146 6.178 6.224
14 

TABLE 9. ANALYTICAL RESULTS FOR LIGHT-DUTY FUELS

DESCRIPTION REGULAR 

E0 

COLD CO 

E0 

NEW COLD 

CO E0 E10 COLD E10 NEW COLD CO E10

FUEL CODE EM-6314-F EM-5574-F EM-6802-F EM-6391-F EM-6378-F EM-6856-F 

PROPERTY TEST METHOD

RVP by Grabner (psi) ASTM D5191 6.99 11.6 11.56 6.82 12.47 12.2

Hydrocarbons by FIA (vol%) 

Aromatics ASTM D1319 24 28.4 28.7 32 26.2 28.5

Olefins 3.3 10.3 9.2 9.6 8.6 9.6

Saturates 72.7 61.3 62.1 58.4 65.2 61.9

Corrected for Oxygenates (vol%) 

Aromatics ASTM D1319 28.68 28.86 23.88 25.64

Olefins 9.19 8.66 7.84 8.64

Saturates 62.06 52.66 59.43 55.68

Sulfur Content (wt%) ASTM D2622 0.0013 0.0027 0.0027 0.0064 0.0033 0.0024

Sulfur Content, (ppm) 13 27 27 64 33 24

API Gravity ASTM D4052 62 61.7 59.6 61.1 60.7 58.2

Specific Gravity (kg/L) ASTM D4052 0.7312 0.732 0.7403 0.7348 0.7364 0.7458

Oxygen and Oxygenates (wt%) 755.5 

MeOH ASTM D4815 ND NM <0.2 <0.2 ND <0.2

EtOH ND NM <0.2

10.32 (9.82 

vol%) 9.54

10.35 (9.72 

vol%)

iPA ND NM <0.2 <0.2 ND <0.2

tBA ND NM <0.2 <0.2 ND <0.2

nPA ND NM <0.2 <0.2 ND <0.2

MTBE ND NM <0.2 <0.2 ND <0.2

sBA ND NM <0.2 <0.2 ND <0.2

DIPE ND NM <0.2 <0.2 ND <0.2

iBA ND NM <0.2 <0.2 ND <0.2

ETBE ND NM <0.2 <0.2 ND <0.2

tPA ND NM <0.2 <0.2 ND <0.2

nBA ND NM <0.2 <0.2 ND <0.2

TAME ND NM <0.2 <0.2 ND <0.2

Benzene ND NM 0.68 1.21 ND 0.6

Total Oxygen ND NM <0.2 3.58 3.31 3.70

Elemental Analysis (wt%)

Carbon Content ASTM D5291 85.78 86.38 86.46 83.34 83.21 83.06

Hydrogen Content 13.56 13.62 13.26 13.14 12.91 13.26

Distillation, deg. F 3.88 

IBP ASTM D86 93 88 82 110 81 88

5% 123 104 95 134 98 103

10% 139 113 108 140 107 112

15% 150 NM 117 144 113 119

20% 160 127 127 148 119 126

30% 180 144 149 154 130 139

40% 201 167 175 174 142 150

50% 220 198 203 216 154 160

60% 237 226 226 234 213 218

70% 256 252 247 258 243 242

80% 284 298 281 289 285 275

90% 317 334 331 329 334 330

95% 340 343 343 360 344 343

FBP 381 367 368 406 363 375

Recovered, mL 97.3 97.6 97.1 98 97.2 97.5

Residue, mL 0.8 1.0 0.5 0.7 1.0 0.7

Loss, mL 1.9 1.4 2.4 1.3 1.8 1.8

ND = Not detected, NM=Not measured
15 

5.2.1.1 Cold CO Fuels

SwRI inadvertently discarded the Cold CO fuel that had been set aside to complete 

testing of the high PM emitting vehicle at 20°F. SwRI contacted the fuel vendor and requested 

more fuel from the same batch but was informed that only a small batch had been blended, and 

all of it was previously purchased by SwRI. SwRI ordered and received a replacement batch of 

Cold CO fuel. Samples of both the original and the replacement Cold CO fuels were analyzed 

by ASTM D6729 to speciate the hydrocarbons for comparison. 

Hydrocarbon speciation results of the two Cold CO fuels are included in Appendix B. 

Table 10 shows a summary comparison of the hydrocarbons where the difference between the 

two fuels was greater than 0.5% (vol.). A graph of the differences of these components is shown 

in Figure 1. Figure 2 shows a comparison of the full speciation of the two Cold CO fuels as 

percentages of each species in the total volume. Ten components were different by more than 

0.5 percent by volume. The greatest differences were found with i-pentane and toluene at +2.97 

percent and -4.13 percent, respectively. The CLOSE project team reviewed the results of the 

new Cold CO fuel analysis and approved continuation of the project with this fuel. 

TABLE 10. COLD CO FUEL COMPONENTS WITH GREATER THAN 0.5% DIFFERENCE

Hydrocarbon

Type Species

Original Cold

CO Fuel, %

New Cold CO 

Fuel, % Original –

New, %

Ratio Of 

Original /

EM-5574-F EM-6802-F New

Paraffin n-Butane 0.528 2.422 -1.89 0.22

Paraffin n-Pentane 5.841 5.173 0.67 1.1

I-Paraffins i-Butane 2.959 4.022 -1.06 0.74

I-Paraffins i-Pentane 20.161 17.194 2.97 1.2

I-Paraffins 2,2,4-Trimethylpentane 3.741 4.542 -0.80 0.8

Mono-Aromatics Toluene 11.942 16.076 -4.13 0.74

Mono-Aromatics 1,2,4-Trimethylbenzene 4.311 3.419 0.89 1.26

Mono-Aromatics 1,2-Dimethyl-4-

ethylbenzene 1.085 0.436 0.65 2.49

n-Olefins Hexene-1 2.812 4.587 -1.78 0.61

Iso-Olefins 3-Methyl-t-hexene-2 5.403 4.294 1.11 1.26
16 

FIGURE 1. COMPARISON OF TWO COLD CO FUELS SHOWING COMPONENTS WITH 

GREATER THAN 0.5 PERCENT DIFFERENCE

FIGURE 2. COMPARISON OF TWO COLD CO FUELS SHOWING ALL SPECIES AS 

PERCENTAGES OF EACH FUEL

-1.9

0.7

-1.1

3.0

-0.8

-4.1

0.9 0.6

-1.8

1.1

-5.0

-4.0

-3.0

-2.0

-1.0

0.0

1.0

2.0

3.0

4.0

Difference in Fuel Component, %

 

 

n-Pentane n-Pentane

i-Pentane i-Pentane

Toluene Toluene

1,2,4-

Trimethylbenzene

1,2,4-

Trimethylbenzene

Hexene-1 Hexene-1

3-Methyl-t-hexene-2 3-Methyl-t-hexene-2

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Original Cold CO Fuel New Cold CO Fuel

Hydrocarbon Species, %
17 

5.2.2 Medium-Duty Vehicle Fuels

The fuels used for emissions testing of the medium-duty vehicles are shown in Table 11. 

Initially we planned to use CARB specification commercial diesel fuel. However, in discussion

with the CARB, it became apparent that diesel fuel sold in California does not always meet the 

exact specifications. CARB grants waivers to the refiners in California which allow them to sell 

fuels that do not actually meet CARB specifications. Typical commercial California diesel fuels 

were compared to Texas commercial low-sulfur diesel fuels. The idea of purchasing commercial 

fuel in California and shipping it to Texas was discussed but the cost of procuring and shipping 

fuel from California was high. Through discussion with the CLOSE project team it was decided 

that we would use Texas commercial diesel with low sulfur content for all straight diesel tests. 

The diesel fuel is called Texas low emission diesel or TxLED, which must have less than 15 ppm 

sulfur. A quantity of pure bio-diesel was purchased from Mid-America Bio Fuels and blended 

with the TxLED diesel to make a twenty percent blend, or B20. The bio-diesel was treated with 

a donated sample of BioExtend(TM) oxidation stabilizer from Eastman Chemical Company.
18 

TABLE 11. ANALYTICAL RESULTS FOR MEDIUM-DUTY FUELS

DESCRIPTION DIESEL - TxLED 100% BIO-DIESEL B20 DIESEL

FUEL CODE EM-6952-F

EM-6981-F 

EM-7029-F a EM-7002-F

PROPERTY UNITS TEST METHOD TEST RESULTS TEST RESULTS TEST RESULTS

Hydrocarbon Type by FIA

Aromatics Volume % ASTM D1319 19.7 Not Applicable b Not Applicable

Olefins Volume % 5.2 Not Applicable Not Applicable

Saturates Volume % 75.1 Not Applicable Not Applicable

Sulfur Content wt% ASTM D2622 <0.001 <0.001 <0.001

Sulfur Content ppm ASTM D2622 <10 <10 <10

API Gravity -- ASTM D287 37.5 28.3 35.4

API Gravity -- ASTM D4052 37.4 28.2 35.5

Specific Gravity -- ASTM D4052 0.8378 0.8863 0.8472

Density at 15°C grams/L ASTM D4052 837.3 885.7 846.7

Kinematic Viscsosity at 40°C cSt ASTM D445 2.677 4.06 2.874

Total Aromatics by SFC

Total Aromatics wt% ASTM D5186 21.7 21.4 c

Mono-aromatics wt% 19.6 19.4

Polynuclear-aromatics (PNA) wt% 2.1 2

Elemental Analysis

Carbon Content wt% ASTM D5291 86.43 77.16 85.08

Hydrogen Content wt% 13.29 12.00 13.47

Carbon fraction -- 0.867 0.772 0.851

Hydrogen fraction -- 0.133 0.120 0.135

Oxygen fraction -- 0 0.108 0.0145 d

Cetane Number -- ASTM D613 47.8 53.6 48.9

Flash Point Deg. F ASTM D93 147 205 153

Flash Point Deg. C 63.9 96.1 67.2

Cetane Index calculated ASTM D976 50.5 46.7 50.8

Oxidation Stability by Rancimat hours EN 14112 >17 2.3 10.7

Distillation

IBP Deg. F ASTM D86 351 231 350

5% NM 624 400

10% 421 630 427

15% NM 630 446

20% NM 632 460

30% NM 634 487

40% NM 635 510

50% 504 636 532

60% NM 637 556

70% NM 640 581

80% NM 643 605

90% 600 645 627

95% NM 644 638

FBP 644 647 650

Recovered, mL ml 97.7 98.6 98

Residue, mL ml 1.2 0.6 1

Loss, mL ml 1.1 0.8 1

Could not maintain baseline 

- Sample not applicable for 

D5186.

a

 Fuel code was changed to EM-7029-F with the addition of an oxidation stabilizer.

b

 Fatty Acid Methyl Esthers in bio-diesel cannot be measured.

c

 Esthers in the bio-diesel are not accounted for. These results are from the diesel portion of the fuel.

d

 20% of the oxygen fraction in the B100 is 0.021. The result shown is within the accuracy of the method. Oxygen content was assumed to be the residual after 

subtracting the carbon and hydrogen fractions which are measured.
19 

5.2.3 Heavy-Duty Diesel Fuel

The analysis of the diesel fuel used for all tests of the heavy-duty vehicles is shown in 

Table 12. For the testing of heavy-duty diesel vehicles, the fuel tanks on the vehicles were 

disconnected from their fuel systems, and a fuel line from the appropriate TxLED or B20 

underground tank was connected to the engine. The commercially available TxLED low sulfur 

diesel fuel was a different batch than the fuel used for medium-duty vehicle tests.

TABLE 12. ANALYTICAL RESULTS FOR HEAVY-DUTY DIESEL FUELS

DESCRIPTION DIESEL - TxLED

FUEL CODE EM-7006-F

PROPERTY UNITS TEST METHOD TEST RESULTS

Hydrocarbon by FIA

Aromatics Volume % ASTM D1319 22.8

Olefins Volume % 1.1

Saturates Volume % 76.1

Sulfur Content wt% ASTM D2622 <0.001

API Gravity -- ASTM D287 37.6

API Gravity -- ASTM D4052 37.8

Specific Gravity -- 0.836

Density at 15°C grams/L 835.5

Kinematic Viscsosity at 40°C cSt ASTM D445 2.656

Total Aromatics by SFC

Total Aromatics wt% ASTM D5186 21.3

Mono-aromatics wt% 19.0

Polynuclear-aromatics (PNA) wt% 2.3

Elemental Analysis (WT%)

Carbon Content wt% ASTM D5291 85.65

Hydrogen Content wt% 13.67

Carbon fraction -- 0.862

Hydrogen fraction -- 0.138

Cetane Number -- ASTM D613 52.6

Flash Point Deg. F ASTM D93 142

Flash Point Deg. C ASTM D93 61

Cetane Index calculated ASTM D976 52.4

Oxidation Stability by Rancimat hours EN-14112 21.2

Distillation, deg. F

IBP Deg. F ASTM D86 353

10% 406

50% 515

90% 596

FBP 628

Recovered ml 97.9

Residue ml 1.3

Loss ml 0.8
20 

5.2.4 Heavy-Duty Natural Gas Fuel

The analysis results of the natural gas fuels used for heavy-duty emissions tests are 

shown in Table 13. Two blends were made for each vehicle tested. Table 13 also shows 

specifications and tolerances for the fuel that were designed to meet the CARB and EPA blend 

specifications for certification-grade natural gas fuel. The natural gas fuels were blended by 

SwRI into large mobile high pressure (2500 psi) spheres which were plumbed to the heavy-duty 

vehicles in place of their fuel tanks.

TABLE 13. NATURAL GAS FUEL BLENDS FOR HEAVY-DUTY VEHICLES

Fuel Component

SwRI 

Specification, 

% vol

Tolerance, 

% vol.

Normal PM Emitter 

Natural Gas Bus

High Mileage Natural 

Gas Bus

Blend 1 Blend 2 Blend 1 Blend 2

Nitrogen 3.50 0.50 3.42 3.58 3.40 3.74

Methane 90.00 1.00 90.18 89.83 90.72 89.99

Carbon dioxide -- 0.50 0.00 0.00 0.00 0.00

Ethylene -- -- 0.00 0.00 0.02 0.02

Ethane 4.00 0.50 4.49 4.61 3.94 4.25

Propane 2.00 0.30 1.90 1.95 1.92 1.99

Butane -- -- 0.00 0.00 0.00 0.00

Elemental Fractions

Carbon -- -- 0.715 0.713 0.715 0.711

Hydrogen -- -- 0.231 0.230 0.231 0.229

Nitrogen -- -- 0.054 0.057 0.054 0.059
21 

6.0 ANALYTICAL PROCEDURES 

6.1 Regulated Emissions

6.1.1 Sampling and Analyses

For the light-duty gasoline vehicles and heavy-duty natural gas vehicles, proportional 

dilute exhaust samples for the determination of hydrocarbons (HC), oxides of nitrogen (NOX), 

carbon monoxide (CO) and carbon dioxide (CO2), as well as ambient samples of THC, CO, CO2, 

and NOX, were collected in Tedlar bags for analysis and were used in the determination of 

gaseous mass emissions rates.11

For the medium-duty and heavy-duty diesel vehicles, HC and NOX were sampled 

continuously from the dilution tunnel using a heated sample probe and filter assembly, and a 

heated sample line, that were all maintained at 375°F±10°F. Proportional dilute exhaust samples 

for CO and CO2, as well as ambient samples of HC, CO, CO2, and NOX were collected in Tedlar 

bags.11

6.2 Non-Regulated Emissions

This section describes the analysis methods for characterization of PM and unregulated 

emissions. All PM analyses were conducted by DRI. The project required the analysis of semivolatile organic compounds (SVOC), in general, and specifically hopanes, steranes, alkanes, 

polycyclic aromatic hydrocarbons, and speciated hydrocarbons in the exhaust samples. The 

compositions of the lubrication oils were compared to the corresponding exhaust samples to 

determine the degree of association in the chemical compositions, thus we analyzed both exhaust 

samples and lube oils for SVOC, as detailed below. In addition, PM samples were analyzed for 

sulfates and their soluble organic fraction (SOF). 

6.2.1 Particulate Matter and Semi-Volatile Organic Compounds

Positive displacement pump-type constant volume sampling (CVS) systems, including 

stainless steel dilution tunnels, were used for all PM sample collection. Separate CVS systems 

were used for the light-, medium-, and heavy-duty vehicles. All dilution air was filtered prior to 

entering the CVS systems. HEPA filters were used to remove particles from the dilution air and 

charcoal filters were used to adsorb background hydrocarbons. Multiple sample probes as shown 

in Figures 3 and 4 were used in each tunnel to facilitate the simultaneous collection of PM 

samples for subsequent analysis as follows: 

• 47-mm Teflon membrane filters: PM mass emission rate, elements by EDXRF and 

ICP-MS, 

• 47-mm glass-fiber filters: SOF

• 47-mm quartz fiber filter: OC and EC by TOR and TOT, sulfate by IC 

• 10-cm TIGF backed up by XAD-4: PAH, hopanes and steranes, higher molecular 

weight alkanes, cycloalkanes

• EEPS: particle size and number count 
22 

The tunnel temperatures at the PM collection zones did not exceed 125°F during testing. 

All PM and SVOC samples, except for those collected to determine PM mass emission rates, 

were shipped to DRI for subsequent analysis. 

The project targeted a minimum filter weight gain in the range of 300 to 500 mg to have 

sufficient material for subsequent chemical analyses. All test durations were based on this target.

FIGURE 3. MULTIPLE PM SAMPLING PROBE INSERT 
23 

FIGURE 4. MULTIPLE PM SAMPLING PROBE INSERTED IN 

LIGHT-DUTY DILUTION TUNNEL

6.2.1.1 Particulate Matter

The CVS system for the light-duty vehicle testing utilized a 10-inch diameter by 16-foot 

long stainless steel dilution tunnel. The CVS system used for medium-duty tests utilized an 18 

inch diameter by 16 foot long stainless steel dilution tunnel. A multi-sample probe was used to 

simultaneously sample 47-mm filters and a 10-cm filter followed by a 2-inch diameter XAD-4 

cartridge. The stainless steel dilution tunnel used in the HD vehicle sampling system is 22 

inches in diameter by 24 feet long, and is configured with two positive displacement pumps 

(PDPs) designed to displace up to a nominal 4,000 cubic feet per minute of dilute exhaust. It 

was equipped with the same multi-probe sampling system used with the light-duty CVS. 

All filters at SwRI were weighed prior to and following sample collection to measure

filter mass increases, using microbalances with a precision (standard deviation) and readability 

of either 1 microgram (0.001 mg) for quartz and TIGF filters or 0.1 microgram (0.0001 mg) for 

Teflon membrane filters. All filters were conditioned in weighing chambers prior to weighing in 

accordance with the 40 CFR Part 86, which specifies the weighing chambers be maintained from 

66 to 77°F and from 37 to 53 percent relative humidity.11 Typically, the conditions in the 

weighing chambers are maintained at 71±5°F and 45±8% relative humidity. Weighing chamber 

temperature, pressure, conditioned air flow rate and relative humidity were monitored on a 

regular basis to ensure that values were within required limits. Prior to weighing, each filter was

placed on a static neutralizer or over an ionizer-blower for at least 30 seconds to avoid any 

problems with static charge.
24 

Two weighed unused 47-mm reference filters and a reference mass remain in the 

weighing chamber at all times. The reference filters are weighed within four hours of any 

sample filter weight, while the reference mass is weighed weekly. If the weight of both 

reference filter(s) change by more than 20 micrograms between sample filter weighing, or if the 

weight of reference mass changes by more than 10 micrograms, an investigation of the cause is 

conducted and filters are reweighed following implementation of a solution. 

 Proportional PM samples drawn from the dilution tunnels were simultaneously collected 

on all filter media and XAD cartridges. For integrated PM samples that were collected over 

multiple days, filters were stored in their holders in the weighing chambers when not in use. 

Following collection, all PM and SVOC samples were stored at -10°C prior to shipment to DRI. 

Samples were shipped overnight to DRI in coolers packed with Blue Ice. 

6.2.1.2 Semi-Volatile Organic Compounds Media Handling by DRI 

 Particulate matter and semi-volatile organic compounds (SVOC) analyzed for this work 

include: PAH, hopanes/steranes, higher molecular weight alkanes, and cycloalkanes. They were

collected using Teflon-impregnated glass-fiber filters (TIGF) followed by XAD-4 resin 

cartridges.15 Prior to sampling, XAD-4 resins were extracted with methanol followed by 

dichloromethane (CH2Cl2), using an Accelerated Solvent Extractor (Dionex 3000). The cleaned 

resin was dried in a vacuum oven heated to 40 oC and stored in sealed glass containers in a clean 

freezer. The TIGF filters were cleaned by sonification in CH2Cl2 for 30 minutes, followed by 

another 30-minute sonification in methanol. Then they were dried, placed in aluminum foil, and 

labeled. Each batch of precleaned XAD-4 resin and ~10% of precleaned TIGF filters were 

checked for purity by solvent extraction and GC/MS analysis of the extracts. The XAD-4 resins 

were assembled into glass cartridges (20g of XAD) and stored in a clean freezer prior to 

shipment to the field. All samples were stored in the freezer, after receiving them from the field 

and prior to extraction. All samples were extracted within two weeks of being received in the 

laboratory. 

For each sample, XAD-4 cartridges and TIGF filters were extracted and analyzed 

separately. Prior to extraction, the following deuterated internal standards were added to each 

filter and XAD sorbent: naphthalene-d8, biphenyl-d10, acenaphthene-d10, phenanthrene-d10, 

anthracene-d10, pyrene-d12, benz(a)anthracene-d12, chrysene-d12, benzo[e]pyrene-d12, 

benzo[a]pyrene-d12, benzo[g,h,i]perylene-d12, coronene-d12, cholestane-d6, hexadecane-d34, and 

eicosane-d42. 

Filters and XAD-4 resins were extracted separately with dichloromethane (DCM) using 

the Dionex ASE followed by hexane extraction under the same conditions. The dichloromethane 

extraction method has been reported to yield high recovery of PAH.16,17 The combination of 

dichloromethane with hexane also gives good recovery for aliphatic hydrocarbons, cycloalkanes, 

hopanes, and steranes.

All extracts were then concentrated by rotary evaporation at 35 °C under gentle vacuum 

to ~1 mL and filtered through a 0.2 μm PTFE disposal filter device (Whatman Pura discTM

25TF), rinsing the flask three times with 1 ml dichloromethane and hexane (50/50 by volume) 

each time. The solvent was exchanged to acetonitrile under ultra-high purity nitrogen. 
25 

The extracts were analyzed first by GC/MS for higher molecular weight (C>14) semivolatile aliphatic hydrocarbons and cycloalkanes, which are the most abundant species in the 

motor vehicle exhaust. Subsequently, the extracts were precleaned by the solid-phase extraction 

technique. Superclean LC-SI SPE cartridges (Supelco) were sequentially eluted with hexane, and 

hexane/benzene (1:1). The hexane fraction contains hopanes and steranes, and the 

hexane/benzene fraction contains PAH and oxy-PAH. These two fractions were combined and 

concentrated to ~100 μL and analyzed by a GC/MS technique for hopane, steranes, PAH and 

oxy-PAH.

6.2.2 PM Elemental Analysis by DRI

6.2.2.1 Gravimetric Analysis by DRI

Unexposed and exposed Teflon-membrane filters and glass-fiber filters were equilibrated 

at a temperature of 21.5±1.5°C and a relative humidity of 35±5% for a minimum of 24 hours 

prior to weighing. Weighing was performed on a Mettler Toledo MT5 electro microbalance with 

±0.001 mg sensitivity. The charge on each filter was neutralized by exposure to a polonium 

source for 30 seconds prior to the filter being placed on the balance pan. The balance was

calibrated with a 200 mg Class 1 weight and the tare was set prior to weighing each batch of 

filters. After every 10 filters were weighed, the calibration and tare were re-checked. If the 

results of these performance tests deviated from specifications by more than ±5 μg, the balance 

was re-calibrated. If the difference exceeded ±15 μg, the balance was recalibrated and the 

previous 10 samples were re-weighed. 100% of the initial weights and 30% of the final weights 

were checked by an independent technician, and samples were re-weighed if these check-weights 

did not agree with the original weights within ±0.010 mg. Pre- and post-weights, check weights, 

and re-weights (if required) were recorded on data sheets and directly entered into a database via 

an RS232 connection. 

6.2.2.2 Energy Dispersive X-Ray Fluorescence (EDXRF) by DRI 

Energy Dispersive X-ray Fluorescence (EDXRF) analysis was performed on Teflonmembrane filters. XRF analyses were performed primarily on a PANalytical Epsilon 5 EDXRF 

analyzer. Ten XRF analyses were averaged by the PANalytical instrument on each sample to 

optimize the detection limits for the specified elements. Calibration against the same standards 

and regular cross-checks between excitation conditions assured comparability of the results. 

Two types of EDXRF standards were used for calibration, performance testing, and 

auditing: (1) vacuum-deposited thin-film elements and compounds from Micromatter Co. (Deer 

Harbor, WA), and (2) polymer films. The vacuum deposit standards cover all elements except 

for Ir, Ta, Zr, and Hf (which may be determined by interpolation) and were used as calibration 

standards. The polymer film and National Institute of Standards and Technology (NIST) 

standards were used as QC standards. During EDXRF analysis, filters were removed from their 

Petri slides, and loaded into holders for entry into the X-ray analysis chamber. The vacuum in the 

X-ray chamber and the heat induced by the absorption of X-rays may volatilize some materials, 

such as ammonium nitrate. A QC standard and a replicate from a previous analysis were 

analyzed with each set of 10 filters. When a QC value differed from specifications by ±10% or 

more, or when a replicate value differed from the original value (where values exceeded 10 times 
26 

the detection limits) by ±10% or more, the previous 10 filters were reanalyzed. If further tests of

standards showed that the system calibration had changed by more than ±5%, the instrument was

recalibrated. In addition, DRI maintained a set of laboratory blanks that were analyzed 

periodically (~1 blank for every 20 filters analyzed) to test for baseline shifts in blank values. 

Also, as part of Level II data validation, field blank values for each shipment were plotted by 

element in time series to check for potential shifts in baselines and potential contamination. After 

EDXRF analysis, the Teflon-membrane filters were returned to their Petri slides and stored under 

refrigeration until the XRF data validation was completed and indicated that the runs were 

acceptable. The EDXRF instrument was also set up for the analysis of liquid samples, including 

lubricating oils and fuels.

6.2.2.3 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) by DRI

The elemental analysis was done with the Thermo Elemental X-7 (Waltham, MA) 

inductively coupled plasma-mass spectrometer (ICP-MS). Filter samples are digested in an 

acidic solution and the resultant 50 ml of the liquid sample is introduced into the system where 

individual elements are measured.

A pump is used to draw 5-10 ml of the liquid sample solution into a nebulizer. The 

nebulized solution is then passed through a plasma torch, which ionizes the dissolved metals. 

The ionized metals pass through a skimmer and sampler cone and then enter a quadrupole. The 

quadrupole filters out all ions except for those within a narrow range of mass-to-charge ratio. 

The ion within this mass-to-charge ratio is then detected by a dynode detector (electron 

photomultiplier). The quadrupole is controlled to allow a series of ions with different mass-tocharge ratios pass through it, permitting a series of different elements to be detected. The ion 

signal detected by the dynode detector is proportional to the amount of the element present in the 

solution. Sample extraction from the PM filter was performed as follows:

Extraction of Filters

• Cut the support ring of the filter in about 8 - 10 places and place it in a digestion 

vessel.

• Add 0.2 ml of ethanol. 

• Add 2 ml of 1:1 HNO3:H2O mixture.

• Add 5 ml of 1:4 HCl:H2O mixture.

• Add 0.1 ml of HF. 

• Place a digestion reflux cap on the digestion vessel and place it in the hot block. 

• Turn on the hot block and heat the digestion vessel for 90 minutes. 

• After 90 minutes, turn off the hot block and remove the digestion vessel. Place the 

vessel in a tray and keep it in the hot block hood to allow the digestion vessel to cool.

• After cooling, bring the digested filter volume up to 50 ml. 

• Cap the digestion vessel, overturn it several times and let sit overnight.
27 

6.2.3 Polycyclic Aromatic Hydrocarbons and Alkanes by DRI

The filters and XAD extracts were analyzed by gas chromatography/mass spectrometry 

(GC/MS), using a Varian CP-3800 GC equipped with a CP8400 autosampler and interfaced to a 

Varian 4000 Ion Trap; due to the high sensitivity of Ion Trap MS, it was used for analysis of all 

semi-volatile and particulate phase organic compounds, with the exception of hopanes and 

steranes. An Electron impact (EI) ionization method was used. Injections (1 μL) were made in 

the splitless mode onto a 30m 5% phenylmethylsilicone fused-silica capillary column (DB-5ms, 

J&W Scientific or equivalent). Quantification of the individual compounds was obtained by 

selective ion storage (SIS) technique, monitoring the molecular (or the most characteristic) ion of 

each compound of interest and the corresponding deuterated internal standard. Calibration curves 

for the GC/MS quantification were made for the most abundant and characteristic ion peaks of 

the compounds of interest using the deuterated species most closely matched in volatility and 

retention characteristics as internal standards. National Institute of Standards and Technology 

(NIST) Standard Reference Material (SRM) 1647 (certified PAH) with the addition of deuterated 

internal standards and of those compounds not present in the SRM (i.e., oxy-PAH, hopanes, 

steranes, hydrocarbons, cycloalkanes) were used to make calibration solutions. A six- to 

eight-level calibration was performed for each compound of interest and the calibration check 

(using median calibration standards) was run every 10 samples to check for accuracy of analyses. 

If the relative accuracy of measurement (defined as a percentage difference from the standard 

value) was less than 20%, the instrument was recalibrated. PAHs and alkanes in the fuels and 

lubricants were also measured in this manner.

6.2.4 Hopanes and Steranes by DRI

The hopanes/steranes were analyzed using the Varian 1200 triple quadrupole gas 

chromatograph/mass spectrometer (GC/MS/MS) system with a CP-8400 autosampler. The

tandem MS/MS system allows for structural elucidation of unknown compounds with precursor, 

product and neutral loss scan. The GC interface allows for sensitive analyses of complex 

mixtures in electron impact (EI) mode. The sensitivity of this instrument in full scan EI/MS 

mode is approximately 1 pg/μl with 20:1 signal-to-noise ratio (S/N). In EI/MS SIM mode, it 

reaches 50 fg/microliter (μl) with 10:1 S/N. This superior sensitivity offers the advantage of 

analyzing small samples collected during a short sampling time. Hopanes and steranes in the 

fuels and lubricants were also measured in this manner.

6.2.5 PM Elemental and Organic Carbon by DRI

The Thermal/Optical Reflectance (TOR) and Transmittance (TOT) methods measure 

“organic” (OC) and “elemental” (EC) carbon. The TOR method is based on the principle that 

different types of carbon-containing particles are converted to gases under different temperature 

and oxidation conditions. The different carbon fractions from TOR are useful for comparison 

with other methods, which are specific to a single definition for organic and elemental carbon. 

These specific carbon fractions also help distinguish among seven carbon fractions reported by 

TOR:
28 

1) The carbon evolved in a helium atmosphere at temperatures between ambient and 

120°C (OC1) 

2) The carbon evolved in a helium atmosphere at temperatures between 120 and 250°C 

(OC2)

3) The carbon evolved in a helium atmosphere at temperatures between 250 and 450°C 

(OC3)

4) The carbon evolved in a helium atmosphere between 450 and 550°C (OC4) 

5) The carbon evolved in an oxidizing atmosphere at 550°C (EC1) 

6) The carbon evolved in an oxidizing atmosphere between 550 and 700°C (EC2)

7) The carbon evolved in an oxidizing atmosphere between 700 and 800°C (EC3) 

The thermal/optical reflectance carbon analyzer consists of a thermal system and an 

optical system. The thermal system consists of a quartz tube placed inside a coiled heater. 

Current through the heater is controlled to attain and maintain pre-set temperatures for given 

time periods. A portion of a quartz filter is placed in the heating zone and heated to different 

temperatures under non-oxidizing and oxidizing atmospheres. The optical system consists of a 

He-Ne laser, a fiber optic transmitter and receiver and a photocell. The filter deposit faces a 

quartz light tube so that the intensity of the reflected laser beam can be monitored throughout the 

analysis.

As the temperature increases from ambient (~25°C) to 550°C, organic compounds are 

volatilized from the filter in a non-oxidizing (He) atmosphere while elemental carbon is not 

oxidized. When oxygen is added to the helium at temperatures greater than 550°C, the elemental 

carbon burns and enters the sample stream. The evolved gases pass through an oxidizing bed of 

heated manganese dioxide where they are oxidized to carbon dioxide, then across a heated nickel 

catalyst, which reduces the carbon dioxide to methane (CH4). The methane is then quantified 

with a flame ionization detector (FID).

The reflected laser light is continuously monitored throughout the analysis cycle. The 

negative change in reflectance is proportional to the degree of pyrolytic conversion from organic 

to elemental carbon, which takes place during organic carbon analysis. After oxygen is 

introduced, the reflectance increases rapidly as the light-absorbing carbon is burned off the filter. 

The carbon measured after the reflectance attains the value it had at the beginning of the analysis 

cycle is classified as elemental carbon. This adjustment for pyrolysis in the analysis is 

significant, as high as 25% of organic or elemental carbon, and it cannot be ignored. 

The system was calibrated by analyzing samples of known amounts of methane, carbon 

dioxide, and potassium hydrogen phthalate (KHP). The FID response was ratioed to a reference 

level of methane injected at the end of each sample analysis. Performance tests of the instrument 

calibration were conducted at the beginning and end of each day's operation. Intervening samples 

were re-analyzed when calibration changes of more than ±10% were found. 

Known amounts of American Chemical Society (ACS) certified reagent grade crystal 

sucrose and KHP were analyzed by TOR as a verification of the organic carbon fractions. Fifteen 

different standards were used for each calibration. Widely accepted primary standards for 

elemental and/or organic carbon are still lacking. Results of the TOR analysis of each filter were

entered into the DRI database.
29 

The Speciation Trends Network (STN) Protocol uses a thermal/optical transmittance 

(TOT) method.18,19

 The difference is that the transmitted laser light is continuously monitored 

throughout the analysis cycle. Also, the temperature steps in the STN thermal evolution protocol 

are 310oC, 480oC, 615oC, and 900oC in a nonoxidizing helium atmosphere and 600oC, 675oC and 

825oC, in an oxidizing atmosphere. The STN method uses fixed hold times of 45 to 120 seconds 

at each heating stage, while IMPROVE method uses variable hold times of 150-580 seconds so 

that carbon responses return to baseline values. 

6.2.6 PM Sulfates

6.2.6.1 Filter Extraction by DRI

Water-soluble sulfates were obtained by extracting the quartz-fiber particle filter. The 

filters were extracted in 15 mL of deionized-distilled water (DDW) in a 15 mL polystyrene 

extraction tube with a screw top cap. The DDW has a measured conductivity of less than 1.8 

milliohms/mL. Each vial was labeled with a barcode sticker containing the filter ID code. The 

extraction tubes were placed in tube racks, and the extraction solution was added. The tubes were

capped and sonicated for 60 minutes, shaken for 60 minutes, than aged overnight to assure 

complete extraction of the deposit into the solvent. The ultrasonic bath water was monitored to 

minimize temperature increases from the ultrasonic energy in the water. After extraction the 

tubes were stored under refrigeration prior to analysis.

6.2.6.2 Ion Chromatographic Analysis for Inorganic Ions and Organic Acids by DRI

Water soluble sulfates were measured with the Dionex 500 (Sunnyvale, CA) ion 

chromatograph (IC). In IC, an ion exchange column separates the sample ions in time for 

individual quantification by a conductivity detector. Prior to detection, the column effluent enters 

a suppressor column where the chemical composition of the component is altered, resulting in a 

matrix of low conductivity. The ions are identified by their elution/retention times and are 

quantified by the conductivity peak area. 

 Approximately two mL of the filter extract were injected into the ion chromatograph. The 

Dionex 500 system of analysis uses a guard column (AG14) for pre-filtering followed by a 

separation column (AS14). The eluent then passes through a self-regenerating suppressor and 

then to the conductivity detector. The resulting peaks were integrated and the integrals were

converted to concentrations using calibration curves derived from solution standards. 

The working calibration standards were prepared from an NIST traceable solution 

purchased from Dionex. They were prepared in concentrations that are compatible in range with 

the expected concentrations of the samples, ordinarily from 0.05 to 5.0 micrograms per mL. A 

calibration curve was generated at the beginning of each run using these prepared standards, 

which were also run as check standards after every tenth sample. Secondary NIST traceable 

check standards from Environmental Research Associates (ERA) were used in each run as 

quality assurance standards. Working standards were prepared as needed, but at least once a 

month. Replicate samples of the extracts were run every ten samples.
 

After analysis, the resulting chromatograms were reviewed on screen for the following: 

proper operational settings, peak shapes, peak overlaps, and quality control comparisons. When 

the values of the standards or the replicate samples varied by more than a percentage based on 

their concentration, the previous 10 samples were rerun. Dilutions were prepared and run if the 

extracts were outside of the calibration range. 

6.2.6.3 PM Soluble Organic Fraction by DRI 

Unexposed and exposed Teflon-membrane filters (47 mm) and glass-fiber filters were 

equilibrated and weighed, as described in Section 6.2.2. These filters were subsequently 

extracted with dichloromethane followed by hexane in an Accelerated Solvent Extractor (Dionex 

3000), dried, reconditioned and re-weighed to determine the Soluble Organic Fraction (SOF). 

DRI used the combination of dichloromethane with hexane, because it gives good recovery for 

aliphatic hydrocarbons, cycloalkanes, PAH, hopanes, and steranes, i.e., the classes of compounds 

that are prevalent in lubricating oil and relevant to this study. These solvents do not extract very 

polar organic compounds, such as diacids or polyalcohols. To account for these classes of 

compounds much more polar solvents are needed, such as acetone, methanol or water. However, 

these solvents extract inorganic compounds as well, thus overestimating SOF. 

6.3 Particulate Number Count and Size Distribution by SwRI 

Particle number (PN) and size were measured using the TSI Engine Exhaust Particle 

Sizer (EEPS). The EEPS was used to measure the number and size of particles from vehicle 

exhaust on a second-by-second basis. The EEPS covers a particle size range from 5.6 nm to 

560 nm. To characterize total (solid plus volatile) and solid particle number-weighted size 

distributions, we used a solid particle sampling system (SPSS) between the engine exhaust 

sample probe and the EEPS. The SPSS is a dilution system that facilitates the measurement of 

total and solid PN. For solid PN measurement with the SPSS, the dilute sample was routed 

through a heated catalytic stripper (CS) that is maintained at 300°C. The CS is a small core of a 

diesel oxidation catalyst designed to have a 100 percent penetration of solid particles and 

complete removal of the volatiles. The volatile materials are typically oxidized at the surface of 

the catalyst. 

All particle size and number measurements conducted on this program were taken from 

engine exhaust using the SPSS/EEPS system. Figure 5 shows a typical experimental setup. The 

overall dilution ratio (DR) was held constant during testing, but the DR level was different for 

different vehicles. The DR is defined as: 

ݓ݋݂݈ ݈݁݌ܽ݉ݏ ൌ ܴܦ ݊݀݋݅ݐݑ݈݅ݎܽ݅ ݓ݋݂݈ ൅ ݓ݋݂݈ ݈݁݌ܽ݉ݏሺ

ሻ

30 
31 

FIGURE 5. EXPERIMENTAL SETUP FOR PARTICLE SIZE AND NUMBER 

MEASUREMENTS

Table 14 shows the type of vehicles tested, along with the DR. The DR ranged from 7 for 

the light-duty gasoline normal emitter to 60 for diesel vehicles. For the EEPS to operate 

properly, a minimum DR of 7 was required to cool the exhaust temperature by dilution to an 

ambient level below 35°C. Cooling by dilution also minimizes thermophoretic particle loss. The 

DR was also chosen to balance between improving the detection limit with the EEPS at low 

concentrations while avoiding instrument saturation at high concentrations. 

TABLE 14. DILUTION RATIO USED FOR DIFFERENT VEHICLES

Normal Emitter High Emitter (or High Mileage)

DR DR

Light-Duty Gasoline 7 16

Medium-Duty Diesel 60 60

Heavy-Duty Natural Gas 20 50

Heavy-Duty Diesel 60 60
32 

For each vehicle, fuel, and lube oil combination tested, three measurements were taken 

with the EEPS over three separate cold-start and hot-start UDCs, performed over a period of 

three days. On Day 1 and Day 3, we measured total particle size and number, and on Day 2 we 

measured the solid particle size and number. Throughout this report, the average total particle 

size and number were determined based on two measurements performed on two separate days. 

The solid particle size and number were reported based on one measurement only. Table 15 

shows a summary of the test matrix with each vehicle tested.

TABLE 15. TEST MATRIX USED FOR EACH VEHICLE, FUEL AND OIL 

COMBINATION

Particle Size And Number Measurement

Day 1 Total (Solid and Volatile)

Day 2 Solid

Day 3 Total (Solid and Volatile)

6.3.1 Particle Mass and Size Distribution

Particle mass-weighted size distribution were measured using the Micro Orifice Uniform 

Deposit Impactor (MOUDI) and nano-MOUDI. This work was done with the light-duty normal 

emitter only using E0 at 72°F with fresh oil. The MOUDI covers a size range from 18 nm to 56 

nm with four size intervals per decade. The nano-MOUDI extends the lower size limit of the 

MOUDI down to 10 nm. Selective stages were used covering the following sizes in nanometer: 

3200, 1800, 1000, 560, 320, 180, 56, 32, 18, and 10. Nuclepore filters were used at each stage for 

PM collection. The mass collected on stages 1000, 320, 180, 56, 32, 18 and 10 nm were used for 

elemental analysis using ICP-MS. Analyses were performed for lube oil derived elements such 

as sulfur, phosphorus, calcium and zinc. The main goal of the MOUDI and nano-MOUDI work

was to determine the size-specific elemental composition of PM.

Particle mass-weighted samples were measured only once from a single test 

configuration. This work was added to the project at the request of NREL. 
33 

7.0 LIGHT-DUTY VEHICLE TESTS

7.1 Vehicle Selection and Description

 Light-duty vehicle selection was made in collaboration with the CLOSE Project 

Management Team. SwRI identified potential candidate vehicles for testing and made vehicle 

recommendations to the Project Management Team. We then waited for technical approval prior 

to procuring the test vehicles. Two LD vehicles were selected and tested, one normal PM emitter 

vehicle and one high PM emitter vehicle.

7.1.1 Light-Duty Vehicle Selection Criteria

• Normal-emitting gasoline vehicle: This was to be a 2002 model year or newer 

gasoline-fueled vehicle with between 30,000 and 75,000 miles on the odometer. The 

target odometer mileage was approximately 50,000. It was expected that this would

be a high-volume, four-door family sedan equipped with a V-6 engine, and would be 

recruited from a local leasing agent.

• High-emitting gasoline vehicle: This was to be a gasoline-fueled vehicle with visible 

smoke related to lubrication oil. The RFP requested a PM emission rate greater than 

200 mg/mi over the Unified Driving Cycle (UDC). This vehicle was solicited from 

SwRI employees, families, and friends. Candidate vehicles were to be screened for 

visual indication of consistent “white” smoke emissions during a variety of driving 

conditions. Consideration was given to the representativeness of the vehicle, as well 

as its ability to be safely and repeatedly tested on a chassis dynamometer. Because 

the specific goal in this project was to obtain a high emitter vehicle which 

demonstrated visually consistent white smoke associated with oil burning, extreme 

care should be taken in extrapolating the allocation results of this single vehicle to 

any more generalized on-road population, even to other high emitter vehicles. This 

vehicle is atypical and may not be representative of any other make or model of onhighway high mileage vehicle. The CLOSE team did not make any effort to 

determine or judge the prevalence or relative population of such vehicles. 

7.1.2 Light-Duty Normal PM Emitter Vehicle Selection and Description

The light-duty normal emitter was a 2006 four-door family sedan with a 3.5L V6 engine. 

It had 30,695 miles on the odometer at the start of testing. It had the fifth highest unit sales 

among passenger cars in calendar year 2006. This car was certified to U.S Federal Tier 2 Bin 8 

standards of 0.125 g/mile for NMOG, 4.2 g/mile for CO, 0.20 g/mile for NOX, and 0.02 g/mile 

for PM at 120,000 miles. It was selected from a list of vehicles available for rental at the 

beginning of the program with input from the Technical Monitor and Project Management Team. 

7.1.3 Light-Duty High PM Emitter Vehicle Selection and Description

The light-duty high PM emitter was a 1993 four-door family sedan with a 4.6L V8 

engine. It had approximately 116,000 miles on the odometer at the start of testing. This car was 
34 

certified to the U.S Federal Tier 1 standard of 0.31 g/mile of NMHC, 4.2 g/mile of CO, 0.6 

g/mile of NOX, and 0.10 g/mile of PM at 100,000 miles. It was solicited from SwRI employees 

and families. A report on the light-duty high PM emitter vehicle was prepared for the CLOSE 

participants. The report in Appendix C describes how the candidate vehicles were solicited and 

gives a description of all the candidates. In addition, the condition of the selected vehicle was 

examined further, and emissions tests were performed to assess its repeatability, plus its oil 

consumption was measured over 300 miles.

7.1.4 Gaseous and PM Emissions Check-Out Tests

A set of three four-phase Unified Cycle check-out tests were conducted to evaluate the 

repeatability of this vehicle before beginning any testing. These tests were performed on three 

separate days with commercial gasoline and engine lubricant as received. Composite and phaselevel PM emission results are given in Table 16. Composite gaseous emission results are given 

in Table 17. These results indicated that the candidate test vehicle had relatively repeatable 

emissions. Following additional vehicle inspections, including determination of oil consumption 

and engine compression checks, it was accepted into the program by the CLOSE Project 

Management Team.

TABLE 16. LIGHT-DUTY HIGH EMITTER FOUR-PHASE UNIFIED CYCLE PM 

EMISSION RATE REPEATABILITY CHECK, mg/mi

Phase 1 Phase 2 Phase 3 Phase 4 Composite

Test 1 31.2 77.3 133.6 130.3 101.1

Test 2 41.4 79.5 133.9 142.9 108.3

Test 3 35.8 61.7 156.7 118.8 91.0

These tests are not part of the PM characterization tests.

Tests were performed at a nominal 72°F, with commercial fuel and lubricant as received.

TABLE 17. COMPOSITE UNIFIED CYCLE GASEOUS EMISSION RATE

REPEATABILITY CHECK, g/mi

THC CO NOX

Test 1 31.2 77.3 133.6

Test 2 41.4 79.5 133.9

Test 3 35.8 61.7 156.7

These tests are not part of the PM characterization tests.

Tests were performed at a nominal 72°F, with commercial fuel 

and lubricant as received.

7.2 Lubricants

The light-duty vehicles were tested with both fresh and aged lubricants that were supplied 

by the American Chemistry Council Product Approval Protocol Task Group. A description of 

the lubricants and the suppliers’ analyses is provided in Section 5.1.1 in Tables 3 and 4. The 

engine’s drain and fill procedure and the lubricant’s initial degreening procedure are also 

described in Section 5.1. Oil samples include the fresh and aged oils as received, and samples 
35 

taken after the cold (20°F) tests with fresh and aged oils on E0 and then E10 for both the normal 

and high emitter. eg. The normal emitter was operated over multiple emission tests with fresh oil 

and a sample was taken from the crankcase drain oil after the cold tests on EO fuels, and then the 

normal emitter was operated over multiple emissions tests with fresh oil on E10 fuels and a 

sample was taken from the crankcase drain oil after the cold tests. Thus five oil samples were 

taken from the normal-emitter (two fuel types and two oils, plus one repeat test on E0 with fresh 

oil), and four oil samples were taken from the high emitter.

7.3 Fuels 

The light-duty vehicles were tested with non-oxygenated gasoline similar to California 

Phase 3 reformulated gasoline, but without ethanol (CA P3 RFG), gasoline with ten percent 

ethanol, which met CA P3 RFG specifications, a certification-grade cold-CO (carbon monoxide), 

gasoline for cold (20°F) tests, and a splash-blend of the cold-CO fuel with denatured ethanol to 

make a ten percent ethanol blend. A second batch of cold-CO fuel was also used in the study 

and it was also blended with ethanol to make a cold-E10 fuel. Descriptions of all the fuels used 

for light-duty testing are included in Section 5.2.1. 

Prior to the initiation of testing on each fuel, the vehicles’ fuel tanks were flushed. An 

example fuel flushing sequence is shown below: 

Fuel Flush Procedure for Light-Duty Vehicles

1. Drain fuel from vehicle.

2. Fill tank with approximately 2 gallons of test fuel. 

3. Cycle ignition twice to build fuel pressure before starting vehicle. Idle vehicle for 

approximately 2 minutes. 

4. Drain fuel from vehicle.

5. Fill tank with approximately 2 gallons of test fuel. 

6. Cycle ignition twice to build fuel pressure before starting vehicle. Idle vehicle for 

approximately 2 minutes. 

7. Drain fuel from vehicle.

8. Fill vehicle full with test fuel.

9. Cycle ignition twice to build fuel pressure before starting vehicle. 

7.4 Emission Test Procedures

This is a pilot study of exhaust emissions effects from the use of different fuels and 

lubricants with some tests conducted at different temperatures. It is important to note that the 

scope of work in this study is limited to short-term effects on emissions when a fuel or lubricant 

was changed. The fuels and lubricants used in this study could have long-term effects on 

emissions which were not measured.

7.4.1 Driving Cycle

The California Air Resources Board LA92 Dynamometer Driving Schedule, often called 

the Unified Driving Cycle (UDC) or LA92, was developed as an emission inventory 
36 

improvement tool.20 A graphic representation of speed versus time for the UDC is presented in 

Figure 6. The distance covered is 9.8 miles for Phases 1 and 2 and average speed is 24.6 mph. 

The UDC is designed to be more representative of all the modes of vehicle operation (hard 

accelerations, etc.) than is the FTP-75. The UDC test has a three-bag structure similar to the 

FTP-75, but is a more aggressive driving cycle than the federal FTP-75. Compared to the FTP75, the LA92 cycle has a higher top speed (67.0 mph versus 56.7 mph), a higher average speed 

(24.8 mph versus 19.6 mph), less idle time (16.4 percent versus 19.0 percent), fewer stops per 

mile (1.52 versus 2.41), and a higher maximum rate of acceleration (3.02 m/s2 versus 1.48 m/s2). 

The LA92 is 9.8 miles long; the FTP-75's length is 7.5 miles. 

FIGURE 6. LA92 UNIFIED DRIVING CYCLE (UDC)

Light-duty vehicles were tested over replicate cold-start UDCs. Thus, only one UDC per 

day was run. The UDC was conducted as a cold-start, four-phase test, in a manner similar to the 

light-duty Federal Test Procedure (FTP). The UDC consisted of a 300-second cold-start phase 

(bag 1) followed by an 1,135-second hot stabilized phase (bag 2), a 10-minute soak, and a hotstart phase (bag 3) which is a repeat of the 300-second bag 1, and (bag 4) 1,135-second hot 

stabilized phase which is a repeat of bag 2. For all emission tests the vehicles were soaked for at 

least 12 hours at test temperature prior to emissions evaluations. The FTP weights emission rates

from bags 1 and 2 at 43 percent, and emission rates from bags 3 and 4 at 57 percent, which are 

then added together to get a composite emission rate. In this study, because particulate matter 

was agglomerated onto single filters over multiple UDCs, and cold-start PM could not be 

separated from hot-start PM, fifty/fifty weighting factors were used to calculate composite UDC 

emission rates for all emissions.

Based on previous experience measuring vehicle PM exhaust emissions during programs 

conducted for NREL and CRC, it is possible for initial PM emission rates to be higher than those 

measured after a number of replicate tests.10,21 It is thought that the PM deposition mechanism in 

the vehicles’ exhaust systems may not have a chance to reach equilibrium during a standard 

vehicle conditioning procedure. This effect could have a major impact on the results of this 

study; therefore, to minimize this effect SwRI performed a conditioning sequence of repeated 

driving cycles with each vehicle prior to sample collection. This conditioning was conducted in 

conjunction with tunnel and sample system conditioning. Tests runs for the light-duty vehicles 

are described as follows: 

0 

10

20

30

40

50

60

70

0 500 1000 1500 2000 2500 3000 3500

SPEED, miles/hour

TIME, seconds

Phase 1 Phase 2 10-minute soak Phase 3 Phase 4
37 

• Normal-Emitting Vehicle

- 72°F (nominal): SwRI conducted 8 cold-start UDCs (approximately 88 miles) to 

generate each set of PM samples. Thus, a total of 64 cold-start UDCs were

conducted at this temperature (8 UDCs per sample × 2 oils × 2 replicate samples

× 2 fuels). For repeatability assessment, an additional repeat test (8 UDCs) of the 

normal-emitting gasoline vehicle operating on gasoline was performed following 

the full test sequence.

- 20°F (nominal): SwRI conducted 2 cold-start UDCs (approximately 22 miles) to 

generate each set of PM samples. Thus, a total of 16 UDCs were conducted at this 

temperature (2 UDCs per sample × 2 oils × 2 replicate samples × 2 fuels). One 

additional test was run for the EEPS measurement without collecting PM samples

for each condition. 

• High-Emitting Vehicle: A single cycle was found to be more than enough to collect 

sufficient sample mass for subsequent analysis at both 72°F and 20°F. Thus, a total 

of 16 UDCs were conducted with this vehicle (1 UDC per sample × 2 oils × 2

replicate samples × 2 temperatures × 2 fuels). One additional test was run for the 

EEPS measurement without collecting PM samples for each condition. 

7.4.2 Chassis Dynamometer

For light-duty vehicles, Clayton Model ECE-50 passenger car dynamometers with directdrive variable inertia flywheel systems were used for testing. The inertia systems on these 

dynamometers can simulate vehicle weights either from 1,000 pounds (lb) up to 4,875 lb in 125-

lb increments or up to 7,250 lb in 250-lb increments. The chassis dynamometers are located in 

an SwRI-built enclosed cell, known as the Temperature Controlled Emissions Enclosure 

(TCEE). The TCEE was designed for testing vehicles from 10°F to 120°F over most driving 

cycles, and was cooled to 20°F for cold-start tests.

7.5 Emission Test Results

7.5.1 Regulated Gaseous and PM Mass Emissions

Summaries of the gaseous and PM emissions for the light-duty vehicle tests are reported 

in this section. Results from detailed characterizations of the PM are reported in subsequent 

sections. The light-duty vehicles were emissions tested with two fuels: a non-oxygenated fuel 

(E0) and an oxygenated fuel (E10), fresh and aged lubricants, and at 72°F and 20°F ambient 

temperatures. Two light-duty vehicles were tested, a normal PM emitter vehicle and a high 

particulate emissions vehicle. The normal PM emissions vehicle is referred to as the normal 

emitter (NE) throughout this document. Likewise, the high PM emissions vehicle is referred to 

as the high emitter (HE).

The Unified Driving Cycle (UDC), or LA-92, was used for all light-duty emissions tests, 

and each light-duty emission test consisted of a cold-start UDC, a ten-minute soak, and a hotstart UDC. For simplicity, a UDC in this project refers to this cold- and hot-start combined test. 

A single cold- and hot-start combined test was performed on any one day, and the vehicles were 

soaked overnight before performing subsequent UDCs. The day before any emission tests for 
38 

record were run, two hot-start UDC cycles were used to prepare the vehicle unless a cold- and 

hot-start UDC has been run already, and then vehicles were soaked overnight. 

Tables 18 and 19 show the average results from the light-duty normal PM emitter (NE) 

vehicle tests at 72°F and 20°F, respectively. Sixteen UDCs for each fuel and lubricant 

combination were performed at 72°F. Two sets of composite PM samples were collected for PM

characterization. Each composite sample set was collected over eight UDCs, to capture enough 

material for analysis. Four UDCs were performed at 20°F for each fuel and lubricant 

combination. Separate composite PM samples were collected over the first and second series of 

two UDCs, to capture enough PM mass for later characterization analysis.

TABLE 18. LIGHT-DUTY NORMAL PM EMITTER VEHICLE AT 72°F

(No Statistical Analyses Were Performed On These Data)

 

72°F -- AVERAGE (AVG) OF 16 UDCS WITH EACH FUEL / LUBRICANT COMBINATION 

GASOLINE E10

FRESH OIL AGED OIL FRESH OIL AGED OIL

AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation

THC, g/mile 0.050 0.007 13% 0.065 0.007 10% 0.086 0.009 10% 0.095 0.009 10%

CO, g/mile 0.639 0.119 19% 0.859 0.137 16% 0.844 0.112 13% 1.019 0.135 13%

NOx, g/mile 0.023 0.004 15% 0.021 0.005 23% 0.047 0.006 12% 0.040 0.005 13%

PMa, mg/mile 0.53 0.12 23% 1.15 0.33 28% 1.72 0.24 14% 1.95 0.30 15%

Fuel Economy, mpg 21.5 0.5 2% 21.4 0.1 1% 21.1 0.2 1% 20.3 0.2 1%

a PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number of replicate UDC tests). 

Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across different temperatures, fuels or lubricants cannot be 

rigorously verified.

TABLE 19. LIGHT-DUTY NORMAL PM EMTTER VEHICLE AT 20°F 

(No Statistical Analyses Were Performed On These Data)

20°F -- AVERAGE (AVG) OF 4 UDCS WITH EACH FUEL / LUBRICANT COMBINATION 

GASOLINE E10

FRESH OIL AGED OIL FRESH OIL AGED OIL

AVG

Standard 

Deviation

Coefficient

of

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation

THC, g/mile 0.215 0.015 7% 0.242 0.020 8% 0.223 0.026 12% 0.290 0.009 3%

CO, g/mile 2.348 0.100 4% 2.647 0.096 4% 2.537 0.061 2% 2.778 0.078 3%

NOx, g/mile 0.049 0.003 6% 0.041 0.005 12% 0.046 0.004 8% 0.043 0.006 13%

PMa, mg/mile 3.93 0.52 13% 4.25 0.52 12% 5.54 0.88 16% 4.98 0.73 15%

Fuel Economy, mpg 20.0 0.4 2% 19.2 0.4 2% 19.7 0.5 3% 18.6 0.1 0%

a PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number of replicate UDC tests). 

Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across different temperatures, fuels or lubricants cannot 

be rigorously verified.

Tables 20 and 21 show the average results from the light-duty high PM emitter (HE) 

vehicle tests at 72°F and 20°F, respectively. A total of three UDCs were performed for each 

fuel, lubricant, and temperature combination in order to measure particulate counts and size 

distributions, but particulate filter sets sampled for later analyses were captured during only two

of the three UDCs.
39 

TABLE 20. LIGHT-DUTY HIGH PM EMITTER VEHICLE AT 72°F

(No Statistical Analyses Were Performed On These Data)

72°F -- AVERAGE (AVG) OF 3 UDCS WITH EACH FUEL / LUBRICANT COMBINATION

GASOLINE E10

FRESH OIL AGED OIL FRESH OIL AGED OIL

AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation

THC, g/mile 0.862 0.039 5% 0.777 0.029 4% 0.909 0.036 4% 0.698 0.017 2%

CO, g/mile 7.88 0.22 3% 7.47 0.33 4% 7.65 0.23 3% 6.73 0.14 2%

NOx, g/mile 0.904 0.051 6% 0.872 0.050 6% 0.955 0.097 10% 0.868 0.005 1%

PMa, mg/mile 198 8.7 4% 172 9.6 6% 198 11.6 6% 122 10.0 8%

Fuel Economy, mpg 18.6 0.2 1% 19.2 0.5 2% 17.8 0.5 3% 18.9 0.8 4%

a PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number of replicate UDC 

tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across different temperatures, fuels or 

lubricants cannot be rigorously verified.

TABLE 21. LIGHT-DUTY HIGH PM EMITTER VEHICLE AT 20°F

(No Statistical Analyses Were Performed On These Data) 

 

20°F – AVERAGE (AVG) OF 3 UDCS WITH EACH FUEL / LUBRICANT COMBINATION

GASOLINE E10

FRESH OIL AGED OIL FRESH OIL AGED OIL

AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation AVG

Standard 

Deviation

Coefficient 

of 

Variation

THC, g/mile 0.998 0.038 4% 0.939 0.041 4% 0.953 0.037 4% 0.710 0.024 3%

CO, g/mile 9.73 0.17 2% 10.30 0.30 3% 8.48 0.42 5% 7.48 0.65 9%

NOx, g/mile 1.415 0.044 3% 1.434 0.050 4% 1.306 0.011 1% 1.300 0.072 6%

PMa, mg/mile 178 4.5 3% 161 13.9 9% 194 10.8 6% 100 6.6 7%

Fuel Economy, mpg 17.1 0.1 1% 17.7 0.2 1% 16.8 0.3 2% 17.4 0.2 1% a PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number of replicate 

UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across different temperatures, 

fuels or lubricants cannot be rigorously verified.

Following the completion of testing of the light-duty normal emitter, NREL requested 

that a repeat test of this vehicle be conducted, at 72°F on non-oxygenated fuel with collection of 

composite PM samples for analyses by Desert Research Institute (DRI) using existing project 

methodologies. In addition, during the repeat test we collected samples using a MOUDI and 

nano-MOUDI and analyzed the samples for Ca, Zn, and other elements. MOUDI results are 

discussed in Section 7.5.2.10. Table 22 shows a comparison of the gaseous and PM emissions 

from the first two replicate tests alongside the repeat (third) test of the light-duty normal emitter 

on fresh oil with non-oxygenated fuel at 72°F. 

During the third test, sequence average HC and CO emission results were slightly higher 

and NOX emission results were slightly lower than the average results from the first two test 

sequences. This indicates that the engine may have run richer during the repeat tests. During the 

repeat test, PM emission rates were double those seen during the first two tests. For verification, 

SwRI re-weighed all the phase-by-phase PM filter samples from these tests and verified that the 

weights were correct.
40 

TABLE 22. COMPARISON OF INITIAL AND REPEAT TEST OF LIGHT-DUTY

NORMAL PM EMITTER

(No Statistical Analyses Were Performed On These Data)

Gasoline With Fresh Oil at 72°F

First Two Tests Third Test

Average of 16 UDCS Average of 8 UDCS

Average

Standard 

Deviation

Coefficient of 

Variation Average

Standard 

Deviation

Coefficient of 

Variation

THC, g/mile 0.050 0.007 13% 0.071 0.006 8%

CO, g/mile 0.639 0.119 19% 0.863 0.081 9%

NOx, g/mile 0.023 0.004 15% 0.016 0.003 18%

PMa, mg/mile 0.53 0.12 23% 1.09 0.14 12%

Fuel Economy, mpg 21.5 0.5 2% 21.6 0.4 2% a PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number of 

replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across different 

temperatures, fuels or lubricants cannot be rigorously verified.

The reason for the nominal increase in PM rate is not known; however, the vehicle was 

tested at cold temperatures and on E10 fuel between the first two tests and the third test. 

Standard deviations within the respective data sets imply operation was comparably stable. Our

records were inspected and dynamometer settings, fuel, engine oil, flushing procedures, and 

initial oil shear stabilization runs were repeated correctly for the third test.

Figures 7 through 13 graphically display the data in Tables 18 through 22. 

FIGURE 7. LIGHT-DUTY AVERAGE HYDROCARBON EMISSION RATES

(No Statistical Analyses Were Performed On These Data)

0.05

0.21

0.09

0.22

0.07

0.24

0.10

0.29

0.86 1.00 0.91 0.95 0.78 0.94 0.70 0.71

0.0

0.2

0.4

0.6

0.8

1.0

1.2

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

HC, g/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL
41 

FIGURE 8. LIGHT-DUTY AVERAGE CARBON MONOXIDE EMISSION RATES

(No Statistical Analyses Were Performed On These Data)

FIGURE 9. LIGHT-DUTY AVERAGE OXIDES OF NITROGEN

EMISSION RATES

(No Statistical Analyses Were Performed On These Data)

0.64

2.35

0.84

2.54

0.86

2.65

1.02

2.78

7.88 9.73 7.65 8.48 7.47 10.30 6.73 7.48

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

CO, g/mile

 

G C O O O SS O S

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL

0.02 0.05 0.05 0.05 0.02 0.04 0.04 0.04 0.90 1.42 0.96 1.31 0.87 1.43 0.87 1.30

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

NOx, g/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL
42 

FIGURE 10. LIGHT-DUTY AVERAGE OXIDES OF NITROGEN EMISSION

RATES – EXPANDED SCALE

(No Statistical Analyses Were Performed On These Data)

FIGURE 11. LIGHT-DUTY AVERAGE FUEL ECONOMY

(No Statistical Analyses Were Performed On These Data)

0.02 0.05 0.05 0.05 0.02 0.04 0.04 0.04 0.90 1.42 0.96 1.31 0.87 1.43 0.87 1.30

0.00

0.02

0.04

0.06

0.08

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

NOx, g/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL

 

21.5 20.0 21.1 19.7 21.4 19.2 20.3 18.6 18.6 17.1 17.8 16.8 19.2 17.7 18.9 17.4

0

5

10

15

20

25

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

FE, mpg

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL
43 

FIGURE 12. LIGHT-DUTY AVERAGE PARTICULATE MATTER 

EMISSION RATES

(No Statistical Analyses Were Performed On These Data)

FIGURE 13. LIGHT-DUTY AVERAGE PARTICULATE MATTER

EMISSION RATES – EXPANDED SCALE

(No Statistical Analyses Were Performed On These Data)

1 4 2 6 1 4 2 5 198 178 198 194 172 161 122 100

0

50

100

150

200

250

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

PM, mg/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL

0.5 3.9 1.7 5.5 1.1 4.2 2.0 5.0 197.6 177.7 198.2 193.6 171.9 160.7 121.7 100.4

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

E0-72 E0-20 E10-

72

E10-

20

PM, mg/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL

EXPANDED SCALE TO SHOW NORMAL EMITTER DATA
44 

7.5.1.1 Discussion of Regulated Emission Results

This section discusses the results presented in Tables 18 through 22 and Figures 7 

through 13. Note that long range precision was not thoroughly explored in the test design. Thus, 

statistical significance of comparisons across different temperatures, fuels, or lubricants cannot

be rigorously verified. 

Figure 7 shows the combined average hydrocarbon emission rates from both the normal 

and high PM emitter. The high emitter produced more hydrocarbons than the low emitter in all 

test cases. For the normal emitter, hydrocarbon emissions increased at cold temperatures in all 

tests, and with E10 increased at least nominally in all cases. Comparing fresh and aged oil tests

with the normal emitter, it appears that the cold tests produced nominally higher hydrocarbons. 

But hydrocarbon emissions from the 72°F tests are not affected by the change from fresh to aged 

oil. For the high emitter, Figure 7 shows that hydrocarbon emissions tend to only nominally 

increase at cold temperatures, but there is no trend in hydrocarbon emissions when comparing E0 

to E10 fuels. 

Figure 8 shows the combined average carbon monoxide (CO) emission rates from both 

the normal and high PM emitter. The high emitter produced higher carbon monoxide emissions 

than the low emitter in all test cases. For the normal emitter, CO emissions increased nominally 

at cold temperatures, with E10 fuel, and increased nominally with aged oil in all tests. For the 

high emitter, Figure 8 shows that CO emissions increased nominally at cold temperatures.

Figures 9 and 10 show the combined average oxides of nitrogen (NOX) emission rates 

from both the normal and high PM emitter. Figure 10 shows the same data as Figure 9 except 

that it is on an expanded scale to show the normal emitter’s NOX emissions. The high emitter 

produced much higher NOX emissions than the low emitter in all test cases. As shown in 

Figure 9, the high emitter produced more NOX at cold temperatures. The high emitter’s NOX

emissions were not affected by changing from fresh to aged oils. On E0 fuel during the 72°F 

tests, in the NE vehicle NOX emissions are nominally lower than all the other tests, but no other 

trends are apparent.

Figure 11 shows the average fuel economy of the light-duty vehicles. The high emitter 

had lower fuel economy than the normal emitter in all test cases but this is expected, because the 

high emitter is heavier, has a larger engine, and has older engine calibrations, hardware, and 

running gear. The cold (20°F) tests with both vehicles all produced nominally worse fuel 

economies than the room temperature tests. For the normal emitter, aged oil produced nominally

lower fuel economy in three of the four configurations, but the high emitter had better fuel 

economy in all configurations with aged oil, which is not surprising. As expected due to its 

lower energy value, the average fuel economy was lower in all cases with E10 fuel compared to 

E0 fuel. 

Figures 12 and 13 show the PM mass emissions from both light-duty vehicles. Figure 13 

shows the same data as Figure 12 but with an expanded scale because the high emitter produced 

much higher emissions than the low emitter. From Figure 12 the PM rates for the higher emitter 

were nominally lower in cold (20°F) temperature tests compared to warm tests, which is opposite 

to the trend shown in Figure 13 for the normal emitter. During cold temperature starts, fuel rates 
45 

are increased to enrich the air-fuel mixture to promote gasoline vaporization and enhance 

startability. The enriched mixture produces more unburned and partially burned hydrocarbons in 

the exhaust and thus an increase in hydrocarbon emissions, as shown in Figure 7. The richer 

combustion mixture also produces more soot. The soot and unburned hydrocarbons can also 

agglomerate together in the exhaust pipe and dilution tunnel and be collected as particulate. 

Thus, cold temperature starts typically produce higher PM emissions.

It is obvious in Figure 13 that the normal emitter’s PM emissions with the low 

temperature starts trend as expected. It is also obvious in Figure 12 that even with fuel 

enrichment, the high emitter’s PM emission rates during low temperature starts are determined 

by some means other than fuel enrichment, because its cold starts produced somewhat less PM 

emissions. Recall that the high emitter is a smoke emitter because it has a high rate of lubricant 

consumption. It appears the HE PM emissions are more influenced by lubricant consumption 

than air/fuel ratio changes caused by low temperature operation. Because at lower temperatures 

lubricants are more viscous and evaporate slower, we hypothesize that during low temperature 

starts less lubricant entered the combustion chamber, and may have remained on the cylinder, 

piston, and head surfaces for a longer period than during room temperature tests. Another 

hypothesis is that during low temperature starts the high emitter’s catalytic converter and exhaust 

system and muffler collected more lubricant aerosols than during room temperature tests, and 

that at lower temperatures this oil was not released back into the exhaust stream.

Comparing the PM emission rate changes due to the use of fresh or aged oils, the low 

emitter does not show a change in PM emission rates, but the high emitter produced less PM

with aged oil than fresh oil. Again, we hypothesize that, since the aged oil lost its lighter 

hydrocarbons as it aged, it is more viscous and evaporates slower than the fresh oil, or, since 

aged oil has more heavy hydrocarbons, more of the lubricant aerosols were collected in the 

vehicle’s exhaust system.

From Figure 12, while it appears that PM emissions from the high emitter vehicle with 

aged oil tended to be lower with E10 fuel than E0 fuel, no such trend is apparent with fresh oil. 

From Figure 13, PM emissions from the NE were nominally higher with E10 than with E0 in 

every case. No reasons supporting these nominal changes are known. 

7.5.2 PM and SVOC Analyses

PM emissions were characterized by analyzing them for elements, semi-volatile organic 

compounds (SVOC), elemental and organic compounds (EC/OC), sulfates, and soluble organic 

fraction (SOF). In the following PM characterization subsections, Tables 23 through 37 present 

the results of these particulate characterizations. Also included in Tables 23 through 37 are the 

results of the analyses of fuels and lubricants and code tables for the hydrocarbon species. PM 

analyses shown in these tables are averaged from a spreadsheet of PM analyses results devised 

by Dr. Eric Fujita of DRI for the apportionment analysis of the light-duty PM emissions. The 

spreadsheet includes the results from each test performed, and is posted at an ftp site at SwRI. 

Dr. Fujita used the spreadsheet data to identify elements of interest in his apportionment study 

which is included in Section 7.6. The third test of the light-duty normal emitter on regular E0 

fuel, with fresh oil, at 72°F temperature is included in a separate column of data for comparison 

to the first two test’s average.
46 

These tables show results with emissions identified on the left of the tables and test 

configurations identified in the top row of the tables. 

7.5.2.1 X-Ray Fluorescence (XRF)

 PM sampled from the light-duty tests was analyzed by DRI for elements by XRF. 

Replicate emission tests were performed in each configuration. Table 23 shows the average 

results in μg/mile of the replicate tests performed in each configuration. 

7.5.2.2 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Analysis

 PM sampled from the light-duty tests was also analyzed by DRI for a subset of eighteen

elements by ICP-MS. Table 24 shows the average results in μg/mile of the replicate tests 

performed in each configuration. The configurations are identified in the top rows of the table, 

and elements measured are shown in the left column. Table 25 shows the results of elemental 

analyses of the lubricants and one fuel. Replicate analyses were performed with three of the 

lubricants. 

7.5.2.3 Polycyclic Aromatic Hydrocarbons

 PM sampled from the light-duty tests was also analyzed by DRI for polycyclic aromatic 

hydrocarbons (PAH). Table 26 shows the average results in μg/mile of the replicate tests 

performed in each configuration. Table 27 shows the results of the lubricant and fuel analyses 

for PAHs. Table 28 shows the codes for the PAH species in Tables 26 and 27. 

7.5.2.4 Alkanes 

 PM sampled from the light-duty tests was also analyzed by DRI for alkanes. Table 29 

shows the average results in μg/mile of the replicate tests performed in each configuration. 

Table 30 shows the codes for the alkane species in Table 29. 

Table 31 shows the results of alkane analyses of the fuels and lubricants from the lightduty vehicles. The first two columns are results from the fresh and aged oils as received from 

the suppliers. The following columns identified by a test number are lubricant analyses from

samples taken from the engine crankcase after the tests in those configurations were completed. 

The last five columns show results of the light-duty fuel analyses for alkanes.
47 

TABLE 23. AVERAGE RESULTS OF LIGHT-DUTY VEHICLE PM ELEMENTAL ANALYSIS BY XRF, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number 

LD-NEF-E0-72LD-NE-FE0-72-3aLD-NEF-E0-20LD-NEF-E10-72LD-NEF-E10-20LD-NEA-E0-72LD-NEA-E0-20LD-NEA-E10-72LD-NEA-E10-20LD-HEF-E0-72LD-HEF-E0-20LD-HEF-E10-72LD-HEF-E10-20LD-HEA-E0-72LD-HEA-E0-20LD-HEA-E10-72LD-HE-AE10-20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp. °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Na 0.96 1.91 2.01 1.76 5.41 2.41 11.22 4.03 7.33 35.9 52.1 50.8 72.7 78.5 72.6 118 60.8

Mg 0.24 0.01 0.00 0.22 1.36 0.10 1.11 0.17 0.20 17.0 18.1 14.0 16.3 17.4 17.6 18.6 12.4

Al 1.39 0.84 4.82 0.87 4.32 0.86 2.79 0.59 1.14 12.1 8.17 7.57 6.79 10.5 12.4 9.3 10.9

Si 2.12 0.88 10.36 1.94 8.04 1.92 4.46 0.76 3.72 22.3 19.5 11.6 13.6 18.4 22.0 21.5 18.9 

P 5.29 6.42 33.0 7.62 47.5 9.45 25.4 9.9 29.6 226 202 171 177 261 305 318 288 

S 2.26 3.11 22.0 8.73 34.1 5.91 22.8 11.2 25.7 284 282 204 242 417 461 428 387 

Cl 1.33 2.83 5.41 4.77 9.15 4.24 6.22 4.29 6.13 13.9 14.4 17.0 15.6 16.6 18.4 13.7 12.0 

K 0.58 0.41 1.63 0.71 2.38 0.75 1.58 0.50 1.55 15.0 14.1 14.4 13.4 14.0 15.2 14.3 12.8

Ca 17.3 19.1 88.9 21.9 126.0 30.8 77.3 30.6 88.7 1273 1164 1214 1181 1182 1294 1252 1126

Sc 0.05 0.11 0.19 0.03 0.38 0.00 0.16 0.05 0.37 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Ti 0.93 0.72 0.39 0.96 0.57 0.82 0.09 0.60 0.07 0.63 0.09 1.17 0.69 0.34 1.06 0.54 0.41

Va 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.18 0.00 0.03 0.02 0.03

Cr 0.50 0.27 1.43 0.63 2.12 0.34 0.97 0.22 1.04 3.03 4.00 0.98 0.91 0.73 1.09 2.09 1.58 

Mn 0.13 0.10 0.80 0.09 1.11 0.12 0.72 0.09 0.63 0.96 0.78 0.34 0.40 0.71 0.88 1.40 1.06 

Fe 5.34 3.40 18.9 4.62 25.10 5.15 14.81 2.90 17.2 35.8 33.2 12.4 14.1 13.8 20.6 46.5 27.1 

Co 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 

Ni 0.28 0.07 0.41 0.25 0.74 0.10 0.32 0.06 0.35 1.50 1.03 0.44 0.45 0.66 1.63 1.46 1.27 

Cu 0.81 0.75 2.62 1.14 4.53 1.08 2.10 0.98 2.22 3.27 2.18 3.23 2.55 8.08 8.91 9.22 8.54

Zn 6.00 7.50 36.5 8.12 50.7 10.0 28.3 10.4 32.4 437 379 363 368 335 412 442 385

Ga 0.00 0.00 0.00 0.00 0.00 0.00 0.12 0.00 0.00 0.00 0.21 0.20 0.00 0.00 0.00 0.00 0.19

As 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.10 0.00

Se 0.01 0.07 0.09 0.02 0.13 0.00 0.23 0.00 0.07 0.25 0.02 0.41 0.06 0.00 0.09 0.36 0.37

Br 0.01 0.09 0.20 0.16 0.20 0.02 0.05 0.12 0.03 0.61 0.30 0.76 0.95 0.32 0.57 0.63 0.84

Rb 0.02 0.00 0.12 0.00 0.00 0.00 0.00 0.00 0.04 0.01 0.04 0.11 0.01 0.11 0.14 0.00 0.04 

Sr 0.01 0.01 0.40 0.07 0.14 0.08 0.11 0.13 0.11 2.25 2.14 2.27 2.07 2.09 2.58 2.34 2.23 

Yt 0.03 0.00 0.13 0.03 0.21 0.03 0.11 0.05 0.15 0.01 0.14 0.02 0.17 0.05 0.26 0.15 0.10 
48 

TABLE 23 (CONT'D). AVERAGE RESULTS OF LIGHT-DUTY VEHICLE PM ELEMENTAL ANALYSIS BY 

XRF, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NEF-E0-72LD-NE-FE0-72-3aLD-NEF-E0-20LD-NE-FE10-72LD-NE-FE10-20LD-NE-AE0-72LD-NEA-E0-20

LDNE-AE10-72LDNE-AE10-20LDHE-FE0-72LDHE-FE0-20LDHE-FE10-72LDHE-FE10-20LDHE-AE0-72LDHE-AE0-20LDHE-AE10-72LDHE-AE10-20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp. °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Zr 0.49 0.38 1.25 0.38 1.87 0.54 0.97 0.34 1.56 0.18 0.30 0.43 1.20 0.04 0.18 0.70 0.61

Nb 0.00 0.00 0.03 0.00 0.08 0.00 0.05 0.00 0.04 0.00 0.05 0.24 0.08 0.00 0.15 0.21 0.17

Mo 0.42 0.53 2.32 0.62 2.81 0.92 2.24 1.08 2.66 40.6 38.4 29.1 30.2 42.4 48.6 48.7 42.6 

Pd 0.00 0.00 0.19 0.02 0.16 0.00 0.11 0.00 0.00 0.00 0.00 0.00 0.28 0.00 0.00 0.00 0.00 

Ag 0.00 0.00 0.00 0.00 0.05 0.00 0.16 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 

Cd 0.04 0.00 0.00 0.00 0.18 0.05 0.00 0.00 0.10 0.48 0.00 0.00 0.33 0.00 0.00 0.00 0.00 

In 0.03 0.03 0.03 0.02 0.00 0.01 0.09 0.02 0.08 0.18 0.00 0.00 0.00 0.06 0.00 0.00 0.00 

Sn 0.02 0.00 0.01 0.03 0.00 0.00 0.05 0.00 0.00 0.00 0.41 0.00 0.00 0.00 0.00 0.00 0.12

Sb 0.00 0.00 0.11 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.72 0.00 0.00 0.00 0.00 0.00

Cs 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Ba 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.06 0.00 0.00 0.00 0.00

La 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.02 0.00 0.02 0.00 0.00 0.00 0.00 0.00 0.04

Ce 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.04 0.00 0.00 0.00

Sm 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.00 0.05 0.07 0.00 0.13 0.00 0.00 0.11 0.18 0.06 

Eu 0.06 0.00 0.00 0.01 0.12 0.04 0.05 0.02 0.05 0.13 0.15 0.00 0.04 0.00 0.00 0.00 0.00 

Tb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.06 0.09 0.00 0.00 0.00 

Hf 0.09 0.00 0.42 0.06 0.68 0.00 0.27 0.05 0.05 1.52 1.56 0.68 0.00 1.53 1.38 2.81 2.60 

Ta 0.21 0.05 0.45 0.08 0.26 0.10 0.00 0.06 0.21 0.89 0.08 1.05 0.92 0.45 0.97 2.02 0.08

Wo 0.00 0.19 0.56 0.00 0.42 0.00 0.23 0.04 0.33 1.56 2.45 2.19 3.39 0.77 0.00 0.00 0.80

Ir 0.04 0.00 0.00 0.00 0.00 0.00 0.04 0.00 0.08 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Au 0.13 0.00 0.00 0.00 0.16 0.00 0.00 0.01 0.00 0.00 0.01 0.00 0.35 0.00 0.00 0.00 0.00

Hg 0.00 0.00 0.00 0.02 0.00 0.02 0.05 0.00 0.00 0.00 0.00 0.00 0.05 0.00 0.00 0.00 0.00

Tl 0.00 0.00 0.00 0.00 0.03 0.00 0.03 0.00 0.11 0.00 0.00 0.03 0.18 0.15 0.03 0.00 0.00

Tb 0.17 0.02 0.07 0.02 0.26 0.16 0.43 0.09 0.04 1.14 0.44 0.20 1.01 0.62 0.26 1.07 0.28 

Ur 0.01 0.00 0.13 0.00 0.00 0.00 0.00 0.00 0.00 0.48 0.00 0.82 0.00 0.00 0.49 0.00 0.00 

a The repeat test of the normal emitter after all other tests were run is included here but not as part of the first two test's averaged data.
49 

TABLE 24. AVERAGE RESULTS OF LIGHT-DUTY VEHICLE PM ELEMENTAL ANALYSIS BY ICP-MS, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NE-FE0-72LD-NE-FE0-72-3a

LDNE-FE0-20LDNE-FE10-72LDNE-FE10-20LDNE-AE0-72LDNE-AE0-20LDNE-AE10-72LDNE-AE10-20LDHE-FE0-72LDHE-FE0-20LDHE-FE10-72LDHE-FE10-20LDHE-AE0-72LDHE-AE0-20LDHE-AE10-72LDHE-AE10-20

Emitter Normal Normal

Norma Norma Norma Norma Norma Norma Norma

High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp, °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20 

Mg 0.28 0.07 1.43 0.23 1.70 0.20 0.92 0.12 1.09 10.4 10.5 9.9 9.7 11.2 12.7 12.9 12.0 

Al 2.53 0.42 9.24 1.42 7.13 1.16 4.10 0.80 4.00 10.7 9.5 5.5 7.0 6.6 8.1 10.4 7.6 

Ca 15.9 16.3 80.0 19.0 110 26.8 68.9 26.6 79.3 1368 1418 1513 1392 1427 1468 1406 1271 

Va 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.04 0.02 0.01 0.01 0.01 0.02 0.02 0.02 

Cr 0.25 0.00 0.81 0.32 0.95 0.00 0.25 0.00 0.95 6.34 3.92 2.92 2.09 2.73 2.88 4.04 2.88

Mn 0.09 0.03 0.44 0.09 0.61 0.07 0.30 0.04 0.35 0.76 0.45 0.30 0.25 0.52 0.67 0.99 0.62

Fe 3.75 1.10 12.88 3.19 16.20 2.31 10.14 0.46 11.40 40.7 28.5 14.8 15.6 13.7 16.1 52.0 22.6

Ni 0.29 0.00 0.25 0.29 0.48 0.00 0.12 0.00 0.22 3.28 1.60 1.02 0.68 0.74 1.13 2.02 1.41

Cu 0.72 0.51 1.87 0.82 2.97 0.80 1.33 0.71 1.34 2.83 1.45 2.80 3.05 7.11 8.08 8.19 7.31

Zn 4.90 5.50 28.5 6.03 39.3 7.46 21.2 7.4 24.4 376 365 358 355 324 361 392 352

Mo 0.34 0.34 1.47 0.40 1.83 0.58 1.40 0.61 1.51 35.9 34.6 26.7 28.3 38.6 40.6 41.3 37.4 

Ag 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.08 0.60 0.25 0.46 0.01 0.00 0.03 0.00 

Cd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 

Sn 0.00 0.00 0.00 0.00 0.01 0.00 0.01 0.00 0.01 0.28 0.32 0.13 0.18 0.35 0.39 0.47 0.45 

Ba 0.58 0.28 0.39 0.50 0.41 0.37 0.08 0.24 0.12 2.28 0.63 3.25 0.86 2.79 1.12 2.66 0.84

Ce 0.05 0.04 0.33 0.05 0.53 0.08 0.25 0.06 0.34 0.04 0.04 0.02 0.02 0.05 0.29 0.21 0.12

Hg 0.01 0.00 0.01 0.01 0.02 0.00 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Pb 0.04 0.00 0.00 0.00 0.00 0.03 0.21 0.00 0.00 0.81 0.60 0.29 0.37 0.35 0.49 0.80 0.57

a The repeat test of the normal emitter after all other tests were run is included here but not as part of the first two test's averaged data.
50 

TABLE 25. LIGHT-DUTY VEHICLE ELEMENTAL ANALYSIS OF FUELS AND LUBRICANTS BY ICP-MS, ng/g

(No Statistical Analyses Were Performed On These Data)

ELEMENTS CONCENTRATIONS, ng/gram

SAMPLE CODE COLD E10 FUEL LD-NE-F-E0 

REP 1

LD-NE-F-E0 

REP 2

LD-NE-A-E0 

REP 1

LD-NE-A-E0 

REP 2 LD-NE-F-E10 LD-NE-A-E10 REP 1

LD-NE-A-E10 

REP 2

Sample Type Fuel Oil Oil Oil Oil Oil Oil Oil

Emitter Both Normal Normal Normal Normal Normal Normal Normal

Oil NA Fresh Fresh Aged Aged Fresh Aged Aged

Fuel EM-6856-F E0 E0 E0 E0 E10 E10 E10

Temp, °F 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Tracer No Yes Yes Yes Yes Yes Yes Yes

Mg <LODa 14143 13903 16260 15829 13919 15184 16181

Al <LOD 1820 1254 7194 7164 1802 6874 6517

Ca <LOD 1940847 1918484 2089479 2071293 1948107 2050272 2034966

Va <LOD 7 5 9 9 7 9 11

Cr <LOD 135 55 345 350 110 337 345

Mn <LOD 429 158 827 827 298 768 771

Fe 59 6183 1887 10412 10430 3393 9382 9519

Ni <LOD 92 32 223 193 103 154 151

Cu 8 5285 2121 15671 15458 3722 15171 15478

Zn <LOD 863385 856665 876769 886816 917314 838830 875179

Mo <LOD 72391 71602 78782 78456 71357 81899 80284

Ag <LOD <LOD <LOD 6 5 <LOD 8 8

Ba <LOD 58 17 65 55 32 42 48

Pb 2 243 109 398 401 147 392 387

W <LOD 3 <LOD 4 3 <LOD 3 3

P <LOD 721877 716541 654430 632582 722491 631292 652123

S 28362 2169961 2081068 2189573 2159864 2221592 2140706 2153047

Ti <LOD 26 <LOD 26 34 28 31 43

Sr <LOD 3109 3128 3134 3168 3130 3326 3080

a Less than Level of Detection
51 

TABLE 26. POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NEF-E0-72

LD-NEF-E0-

72-3

LD-NEF-E0-20

LD-NEF-E10-

72

LD-NEF-E10-

20

LD-NEA-E0-72LD-NEA-E0-20

LD-NEA-E10-

72

LD-NEA-E10-

20

LD-HEF-E0-72LD-HEF-E0-20

LD-HEF-E10-

72

LD-HEF-E10-

20

LD-HEA-E0-72LD-HEA-E0-20

LD-HEA-E10-

72

LD-HEA-E10-

20

Source Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp, °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Mediab F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD

TB 

Correctionc Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

naphth 51.2 34.5 552.8 70.6 228.1 28.8 590.0 56.9 186.0 851.5 1360.4 1501.1 1361.3 1149.0 771.3 1327.2 560.1

quinoline 0.0 0.2 0.5 0.7 0.9 0.2 0.7 1.7 1.9 20.9 27.6 50.3 44.4 36.3 51.3 45.5 36.0

mnaph2 16.9 18.5 72.8 67.2 74.3 22.1 73.3 89.7 122.4 432.8 192.3 1117.4 325.0 715.0 381.8 1075.3 293.3

mnaph1 10.3 11.0 49.4 43.4 46.7 13.9 50.2 55.3 81.8 239.4 125.3 555.8 196.0 392.5 243.5 537.0 167.6

biphen 1.5 1.6 15.3 4.9 11.9 1.9 16.7 6.0 23.4 31.3 31.5 47.5 34.9 49.4 51.3 41.3 28.6

m_2bph 1.1 0.7 2.7 0.1 5.4 0.4 2.9 0.5 9.1 0.0 0.1 0.1 0.1 0.0 0.0 0.0 0.0

dmn267 1.5 1.3 4.2 6.7 5.1 2.3 4.2 10.0 7.4 54.2 28.7 108.0 52.9 90.7 62.1 104.7 44.5

dm1367 2.9 2.3 9.5 10.4 9.9 3.9 8.9 15.5 15.7 98.1 59.3 171.2 93.5 156.3 116.5 155.6 75.8

d14523 1.0 0.7 3.6 2.8 3.8 1.2 3.8 4.0 6.3 34.1 24.3 50.0 36.0 54.1 46.7 42.7 26.7

enap12 1.6 2.0 20.7 7.5 17.6 2.7 22.0 11.5 37.2 69.6 44.0 131.7 67.4 105.9 82.5 121.5 54.3

acnapy 1.7 1.3 49.3 3.7 21.8 1.4 42.0 4.2 44.0 35.6 102.2 41.3 91.0 45.4 157.3 32.8 69.8

dmn12 0.4 0.3 1.8 1.1 1.8 0.5 2.1 1.7 3.5 16.2 18.8 23.4 25.1 29.0 42.9 18.9 15.9

dmn18 0.0 0.0 0.2 0.0 0.2 0.0 0.1 0.2 0.2 0.0 0.3 0.4 0.4 0.4 0.8 0.3 0.4

acnape 0.0 0.1 36.3 0.3 30.4 0.2 46.6 0.4 79.8 3.4 9.2 4.9 8.7 5.1 15.8 4.1 6.0

m_3bph 2.4 1.6 2.9 2.0 1.3 1.4 2.0 2.1 0.7 9.0 2.1 1.9 1.5 18.1 12.3 0.8 0.3

m_4bph 0.6 0.5 1.6 0.7 1.8 0.5 2.2 0.8 3.9 5.3 1.8 2.2 1.4 9.5 6.2 0.9 0.5

dbzfur 1.0 0.1 2.5 1.2 2.2 0.5 2.4 1.2 2.4 7.9 8.8 9.9 10.0 14.3 15.5 9.4 8.5

em_12n 1.0 0.4 2.3 2.3 1.1 0.3 0.6 1.1 1.3 9.7 8.0 11.5 10.3 15.7 13.7 8.0 6.7

tmi235n 0.4 0.2 0.6 0.5 0.8 0.4 0.5 0.4 0.7 13.3 5.9 7.0 8.3 16.9 8.6 6.4 3.3

btmnap 0.5 0.5 0.5 0.6 1.0 0.5 0.3 1.3 0.8 21.3 15.7 22.4 15.0 31.6 27.0 18.5 13.9

atmnap 0.6 0.7 0.9 1.9 0.8 1.1 0.0 2.2 4.8 32.7 23.3 38.8 28.0 50.0 38.5 33.8 21.7

ctmnap 0.5 0.4 0.6 0.7 1.0 0.5 0.4 1.2 1.3 17.4 12.6 17.5 15.1 26.4 22.2 14.9 5.5

em_21n 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.2 2.3 2.2 2.3 2.6 3.7 3.9 1.9 1.5

etmnap 0.3 0.2 0.5 0.4 0.5 0.3 0.5 0.6 0.7 9.7 6.5 9.1 7.2 13.7 11.3 7.8 4.9

tm245n 0.0 0.1 0.5 0.1 0.2 0.1 0.1 0.1 0.2 3.5 2.6 3.5 4.0 4.6 6.0 1.4 2.2

ftmnap 0.3 0.2 0.3 0.4 0.4 0.3 0.4 0.6 0.5 9.2 6.9 8.9 7.5 13.4 12.2 7.1 5.9
52 

TABLE 26 (CONT'D). POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NEF-E0-72

LD-NEF-E0-

72-3

LD-NEF-E0-20

LD-NEF-E10-

72

LD-NEF-E10-

20

LD-NEA-E0-72LD-NEA-E0-20

LD-NEA-E10-

72

LD-NEA-E10-

20

LD-HEF-E0-72LD-HEF-E0-20

LD-HEF-E10-

72

LD-HEF-E10-

20

LD-HEA-E0-72LD-HEA-E0-20

LD-HEA-E10-

72

LD-HEA-E10-

20

Source Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp, °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Mediab F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD

TB 

Correctionc Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

fluore 0.8 0.7 5.4 1.4 3.4 0.9 6.0 1.7 7.9 17.7 26.6 17.0 26.1 24.1 38.9 15.5 21.2

tm145n 0.0 0.0 0.2 0.1 0.1 0.1 0.1 0.1 0.2 1.4 1.8 2.9 1.7 2.8 3.8 1.7 1.7

jtmnap 0.0 0.1 0.1 0.1 0.2 0.1 0.1 0.1 0.2 4.0 1.7 3.0 3.8 5.0 5.8 1.7 1.2

a_mfluo 0.1 0.3 0.1 0.4 0.6 0.3 0.5 0.4 0.8 8.0 8.7 4.2 7.0 10.1 8.2 4.1 5.3

b_mfluo 0.0 0.1 0.1 0.0 0.1 0.1 0.1 0.0 0.2 1.4 1.3 0.9 1.5 1.8 3.1 1.4 1.5

m_1fluo 0.0 0.1 0.6 0.4 0.7 0.1 0.7 0.5 0.8 6.3 6.1 4.9 4.9 6.8 8.9 4.8 5.4

fl9one 0.8 1.0 2.2 2.5 2.7 1.2 2.5 2.5 3.4 15.2 14.1 14.2 13.1 15.2 17.6 13.2 11.1

phenan 0.9 1.3 9.9 3.1 8.5 1.6 11.6 3.5 16.9 27.3 39.7 23.7 35.6 31.9 59.2 25.8 30.3

anthra 0.3 0.4 1.9 0.8 1.6 0.5 2.1 1.0 3.0 6.4 10.7 5.5 9.3 8.3 15.2 5.7 7.6

xanone 0.1 0.1 0.1 0.2 0.1 0.2 0.0 0.2 0.1 0.4 0.3 0.2 0.2 0.3 0.5 0.6 0.5

acquone 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

m_2phen 0.1 0.1 0.3 0.2 0.4 0.2 0.3 0.3 0.5 10.9 9.0 6.1 6.6 8.3 10.0 6.3 6.0

m_3phen 0.2 0.2 0.4 0.3 0.4 0.3 0.3 0.4 0.6 11.2 9.9 6.7 7.2 9.4 10.7 6.6 4.8

pnapone 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.2 0.2 0.4 0.3 0.5 0.5 0.1 0.6 0.4 0.1

m_2anth 0.1 0.1 0.4 0.1 0.4 0.1 0.3 0.2 0.6 1.1 2.2 0.8 1.3 2.0 2.8 1.2 1.6

m_45phen 0.0 0.1 0.9 0.2 0.8 0.1 0.9 0.2 1.2 1.5 2.7 0.9 2.4 1.5 2.3 0.7 2.6

m_9phen 0.1 0.1 0.2 0.1 0.3 0.1 0.2 0.1 0.3 4.3 4.0 3.1 3.3 4.0 1.8 1.1 2.4

mpht_1 0.1 0.2 0.1 0.2 0.1 0.1 0.2 0.3 0.5 4.3 4.3 2.2 3.0 3.0 3.3 2.9 2.1

anthron 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 1.8 0.5 0.6 0.7 0.5 0.5 0.5 0.4

m_9ant 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.2 0.1 0.2 0.1 0.2 0.1 0.1

nap2phen 0.1 0.1 0.5 0.3 0.6 0.2 0.5 0.3 0.8 6.2 6.7 3.4 4.5 4.4 8.2 4.4 3.8

anrquone 0.2 0.1 0.1 0.3 0.2 0.2 0.1 0.2 0.1 2.7 1.6 1.8 1.2 2.3 2.2 1.4 0.6

a_dmph 0.1 0.0 0.0 0.1 0.0 0.1 0.0 0.1 0.0 5.6 5.0 3.3 2.9 3.5 4.5 2.9 2.4

b_dmph 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.0 2.1 1.0 1.5 2.1 2.5 1.6 1.1

dm17ph 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 3.5 2.8 2.0 1.8 2.1 2.6 1.7 1.0

dm36ph 0.0 0.0 0.2 0.0 0.3 0.0 0.0 0.1 0.1 3.5 3.5 2.7 2.1 2.6 3.3 2.2 1.4
53 

TABLE 26 (CONT'D). POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NEF-E0-72

LD-NEF-E0-

72-3

LD-NEF-E0-20

LD-NEF-E10-

72

LD-NEF-E10-

20

LD-NEA-E0-72LD-NEA-E0-20

LD-NEA-E10-

72

LD-NEA-E10-

20

LD-HEF-E0-72LD-HEF-E0-20

LD-HEF-E10-

72

LD-HEF-E10-

20

LD-HEA-E0-72LD-HEA-E0-20

LD-HEA-E10-

72

LD-HEA-E10-

20

Source Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp, °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Mediab F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD

TB 

Correctionc Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

d_dmph 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 2.1 1.9 1.5 1.5 1.7 1.7 1.2 1.4

e_dmph 0.0 0.1 0.0 0.0 0.1 0.0 0.1 0.0 0.1 1.9 3.4 2.1 1.3 2.4 2.6 2.2 1.6

c_dmph 0.1 0.1 0.0 0.1 0.0 0.1 0.1 0.1 0.1 6.8 6.1 4.1 4.1 4.8 5.7 3.9 3.2

fluora 0.3 0.3 2.5 0.8 2.2 0.3 2.8 0.8 3.5 12.1 18.5 10.4 13.0 8.2 21.2 10.3 10.0

pyrene 0.3 0.7 2.6 0.9 2.5 0.4 3.1 1.1 4.0 17.5 23.2 16.2 17.4 11.3 23.7 13.9 12.4

antal9 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.6 1.0 0.5 0.5 0.4 0.7 0.5 0.4

retene 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0

bafluo 0.0 0.0 0.1 0.0 0.1 0.0 0.0 0.0 0.1 0.8 2.5 0.9 0.8 0.4 0.8 0.4 0.3

bbfluo 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.1 0.2 0.2 0.1 0.2 0.1 0.3 0.2 0.1

bmpyfl 0.0 0.0 0.1 0.0 0.1 0.0 0.0 0.0 0.0 2.5 3.5 1.1 1.4 1.5 3.2 1.2 1.2

c1mflpy 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 4.8 4.5 1.8 1.8 2.5 4.3 2.5 1.2

m_13fl 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.1 1.6 1.3 1.3 1.2 0.7 2.0 1.3 1.2

m_4pyr 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.0 5.1 5.4 4.7 4.0 2.8 4.3 3.3 1.7

cmpyfl 0.0 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.3 0.2 0.2 0.3 0.2 0.4 0.2 0.1

dmpyfl 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 5.8 5.5 5.2 4.1 2.8 5.0 4.4 2.8

m_1pyr 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 2.3 2.6 1.7 1.6 0.5 1.9 1.5 1.1

bntiop 0.0 0.0 0.3 0.0 0.1 0.0 0.0 0.1 0.0 0.4 0.2 0.2 0.3 0.3 0.6 0.3 0.2

bzcphen 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.1 0.6 1.7 0.6 0.2 0.4 0.8 0.3 0.5

bghifl 0.0 0.3 0.9 0.3 0.9 0.2 1.3 0.4 1.5 3.8 8.0 0.7 0.2 0.1 3.6 2.2 2.9

phant9 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0

cp_cdpyr 0.0 0.0 0.4 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.2 0.1 0.1 0.1 0.2 0.3 0.2

baanth 0.0 0.0 0.1 0.1 0.1 0.0 0.2 0.1 0.2 0.9 1.6 0.3 0.1 0.1 0.9 1.3 0.9

chr_tr 0.0 0.1 0.3 0.1 0.3 0.1 0.4 0.1 0.5 5.5 6.5 3.9 4.4 3.9 6.7 3.5 2.4

bzanthr 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.2 1.3 1.7 0.4 0.2 0.4 1.0 1.2 0.5

baa7_12 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.7 0.2 0.8 0.2 0.5 0.6 0.4 0.2

m_3chr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.3 1.0 0.8 0.5 0.5 0.7 0.7 0.5
54 

TABLE 26 (CONT'D). POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NEF-E0-72

LD-NEF-E0-

72-3

LD-NEF-E0-20

LD-NEF-E10-

72

LD-NEF-E10-

20

LD-NEA-E0-72LD-NEA-E0-20

LD-NEA-E10-

72

LD-NEA-E10-

20

LD-HEF-E0-72LD-HEF-E0-20

LD-HEF-E10-

72

LD-HEF-E10-

20

LD-HEA-E0-72LD-HEA-E0-20

LD-HEA-E10-

72

LD-HEA-E10-

20

Source Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp, °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Mediab F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD

TB 

Correctionc Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

chry56m 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.8 0.8 0.1 0.5 0.1 0.5 0.0 0.1

m_7baa 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.1 0.1 0.1 0.1 0.1 0.1

dmban712 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.0 0.3 0.0 0.3 0.2 0.3 0.2 0.1 0.1 

bbjkfl 0.0 0.0 0.1 0.0 0.1 0.0 0.2 0.0 0.2 0.2 0.6 1.1 0.6 0.4 0.4 0.4 0.2

bafl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0

bepyrn 0.0 0.0 0.2 0.0 0.2 0.0 0.3 0.0 0.3 2.4 2.4 0.9 0.9 1.2 2.4 1.6 1.1

bapyrn 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.1 0.1

peryle 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.0

m_7bpy 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.1 0.0 0.0 0.1 0.1 0.1

bpy910dih 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.0 0.1 0.0 0.0 0.1 0.0 

incdfl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbahacr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.1 0.0 0.0 0.0 0.0 0.0

dbajacr 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0

in123pyr 0.0 0.0 0.3 0.0 0.2 0.0 0.5 0.0 0.6 0.1 0.0 0.0 0.0 0.0 0.0 0.1 0.0

dbahacan 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbajan 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0

bbchr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0

pic 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.1 0.0 0.0 0.0 0.0 0.0

bghipe 0.0 0.0 0.5 0.0 0.4 0.0 0.8 0.0 1.0 0.1 0.5 0.2 0.1 0.2 1.9 0.7 0.8

anthan 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbalpyr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

corone 0.0 0.0 0.2 0.0 0.1 0.0 0.2 0.0 0.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbaepyr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 

dbaipyr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbahpyr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbbkfl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 a The repeat test of the normal emitter after all other tests were run is included here but not as part of the first two test's averaged data. b Filter XAD cartridge samples

c Test samples were corrected by subtracting the many tunnel blank measurements
 

55 

TABLE 27. LIGHT-DUTY VEHICLE FUELS AND LUBRICANTS POLYCYCLIC AROMATIC HYDROCARBONS, μg/g 

(No Statistical Analyses Were Performed On These Data)

Test

Number LO-221459 LO-223292

LD-NE-FE0LD-NE-FE0-REP LD-NE-FE10LD-NE-AE0LD-NE-AE10LD-HE FE0LD-HE-FE10LD-HE-AE0LD-HE-AE10 EM-6314-F EM-6391-F EM-5574-F EM-6378-F EM-6802-F 

Emitter

Oil as 

received

Oil as 

received Normal Normal Normal Normal Normal High High High High NE & HE NE & HE NE & HE NE & HE NE & HE

Oil Fresh Aged Fresh Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A F&A F&A F&A

Fuel NA NA E0 E0 E10 E0 E10 E0 E10 E0 E10 E0 E10 Cold CO Cold E10

New Cold CO 

(E0)

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 72 20 20 20

Media Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel Fuel Fuel Fuel 

naphth 0.0 129.6 322.9 231.3 390.5 418.9 347.3 508.9 537.0 276.7 48.4 2077.1 3724.2 2514.5 2596.1 1608.7

quinoline 0.0 3.2 0.0 0.0 0.5 0.2 0.3 0.2 0.3 0.4 0.8 1.3 54.9 0.1 0.0 0.0

mnaph2 0.0 201.7 89.9 299.4 311.3 93.4 303.7 201.5 307.4 210.1 111.7 1190.4 3932.9 4.9 6.5 91.3

mnaph1 0.0 105.2 55.3 162.5 156.7 50.8 152.3 120.4 171.9 120.4 67.2 577.4 1672.8 0.1 1.2 44.0

biphen 0.0 0.5 1.6 5.3 7.9 2.3 8.0 2.2 6.3 6.0 2.0 16.8 45.2 0.0 0.1 0.6

m_2bph 0.0 0.3 0.8 3.2 0.8 1.5 2.9 3.0 2.3 1.2 0.0 4.5 12.0 0.0 0.0 0.0

dmn267 0.0 22.8 31.0 62.6 74.6 24.7 75.5 30.4 45.4 32.2 17.3 122.0 364.8 0.0 0.3 5.7

dm1367 0.1 37.3 57.9 108.4 122.1 49.1 121.0 59.5 94.4 63.7 33.0 206.2 504.1 0.0 0.6 11.4

d14523 0.8 64.6 20.1 34.8 29.8 16.7 35.8 107.5 150.8 121.2 52.0 64.7 116.9 0.0 0.0 21.4

enap12 0.0 16.4 15.0 35.1 44.0 12.0 43.9 34.3 44.4 38.4 15.3 69.4 210.5 0.0 0.0 5.3

acnapy 0.0 0.1 0.2 0.9 0.2 1.5 0.2 2.1 1.3 1.2 0.0 1.4 1.6 0.0 0.0 0.0

dmn12 0.0 7.7 8.8 19.3 9.7 7.3 11.2 14.7 13.6 17.7 2.7 27.2 41.2 0.0 0.0 2.6

dmn18 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

acnape 0.3 0.5 1.0 1.7 0.3 0.2 0.4 0.2 1.0 0.4 0.3 3.6 4.1 0.0 0.0 0.0

m_3bph 0.2 5.3 15.3 22.2 10.9 12.4 7.7 28.2 13.6 24.5 4.5 30.6 14.2 0.0 0.0 0.3

m_4bph 0.0 1.4 7.0 9.6 1.9 5.0 2.9 11.4 5.4 12.8 1.6 13.0 4.9 0.0 0.0 0.1

dbzfur 0.0 0.0 0.1 0.0 0.4 0.0 0.0 2.2 0.4 1.7 0.0 0.0 1.2 0.0 0.0 0.0

em_12n 0.2 3.0 8.2 11.6 3.7 6.9 5.2 12.8 7.2 11.5 1.1 11.0 9.7 0.0 0.0 0.4

tmi235n 0.1 13.2 34.7 37.5 22.4 29.7 27.4 54.2 25.0 48.4 11.4 36.5 21.7 0.0 0.0 1.3

btmnap 0.4 10.8 33.3 42.1 27.8 29.5 29.4 51.2 37.6 50.1 9.4 45.8 42.7 0.0 0.0 3.3

atmnap 0.6 15.8 36.0 46.2 32.8 27.5 32.1 54.2 48.9 51.2 11.3 57.9 61.1 0.0 0.0 0.8

ctmnap 0.6 12.4 28.7 40.0 21.8 26.2 28.7 48.1 28.4 45.2 8.4 37.4 34.2 0.0 0.0 3.6

em_21n 0.0 0.7 0.8 2.0 0.3 0.9 1.6 0.2 0.5 1.4 0.0 0.9 1.5 0.0 0.0 0.1

etmnap 0.1 7.7 19.3 27.2 15.8 18.9 15.7 31.6 19.6 33.1 5.2 22.4 19.6 0.0 0.0 2.2

tm245n 0.1 2.1 9.8 0.7 1.4 8.5 4.5 9.4 5.2 8.4 0.4 0.8 0.2 0.0 0.0 0.2

ftmnap 0.2 6.8 18.8 24.2 16.0 17.8 18.3 33.4 22.2 30.9 6.7 23.4 19.6 0.0 0.0 2.2

fluore 0.2 3.6 13.8 1.2 14.9 12.9 12.6 21.0 11.3 19.0 3.2 1.3 10.7 0.0 0.0 0.1
 

56 

TABLE 27 (CONT'D). LIGHT-DUTY VEHICLE FUELS AND LUBRICANTS POLYCYCLIC AROMATIC HYDROCARBONS, 

μg/g 

(No Statistical Analyses Were Performed On These Data)

Test

Number LO-221459 LO-223292

LD-NE-FE0LD-NE-FE0-REP LD-NE-FE10LD-NE-AE0LD-NE-AE10LD-HE FE0LD-HE-FE10LD-HE-AE0LD-HE-AE10 EM-6314-F EM-6391-F EM-5574-F EM-6378-F EM-6802-F 

Emitter

Oil as 

received

Oil as 

received Normal Normal Normal Normal Normal High High High High NE & HE NE & HE NE & HE NE & HE NE & HE

Oil Fresh Aged Fresh Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A F&A F&A F&A

Fuel NA NA E0 E0 E10 E0 E10 E0 E10 E0 E10 E0 E10 Cold CO Cold E10

New Cold CO 

(E0)

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 72 20 20 20

Media Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel Fuel Fuel Fuel 

tm145n 0.2 2.5 8.5 8.3 0.9 6.8 0.3 5.5 1.7 4.2 0.3 7.1 1.3 0.0 0.0 0.2

jtmnap 0.1 1.4 10.2 11.8 6.7 8.0 7.2 16.1 9.5 16.5 1.0 8.4 0.4 0.0 0.0 0.0

a_mfluo 0.3 8.7 38.5 29.9 31.2 31.7 29.3 53.3 20.0 37.2 7.4 20.5 1.5 0.0 0.0 0.0

b_mfluo 0.1 0.5 6.1 4.7 4.9 6.2 5.3 11.7 2.0 4.5 0.3 4.0 0.7 0.0 0.0 0.0

m_1fluo 0.3 0.3 11.5 15.2 16.1 14.4 14.2 34.3 1.7 21.3 5.2 9.0 2.7 0.0 0.0 0.0

fl9one 0.0 0.3 1.8 1.7 1.5 1.4 1.5 1.2 0.5 0.8 0.3 0.5 0.2 0.0 0.0 0.0

phenan 0.3 12.7 28.6 26.2 26.9 29.2 26.3 59.6 31.3 44.2 10.0 12.5 8.7 0.0 0.0 0.0

anthra 0.0 4.4 11.9 9.6 4.3 12.4 7.7 25.0 6.4 14.6 4.7 4.3 1.0 0.0 0.0 0.0

xanone 0.2 0.8 3.3 1.9 3.0 3.0 2.0 11.0 0.7 6.2 1.1 0.5 0.2 0.0 0.0 0.0

acquone 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

m_2phen 0.4 25.8 44.1 31.7 32.9 51.3 39.9 82.0 37.8 63.8 18.4 11.2 6.5 0.0 0.1 0.0

m_3phen 0.2 17.9 40.0 31.7 45.9 51.8 46.6 86.4 45.9 66.3 21.2 11.4 4.2 0.0 0.0 0.0

pnapone 0.8 0.8 4.0 1.1 2.0 1.6 2.3 1.6 4.6 4.3 0.6 0.1 0.2 0.0 0.1 0.0

m_2anth 0.1 11.3 18.4 10.9 4.6 18.8 12.6 29.6 7.9 29.4 8.3 3.1 0.2 0.0 0.0 0.0

m_45phen 0.3 2.4 3.9 2.5 1.5 4.0 1.2 11.1 3.6 7.9 1.4 0.1 0.1 0.0 0.0 0.0

m_9phen 0.1 11.5 13.3 13.5 9.8 15.4 9.6 18.2 14.7 29.8 13.5 3.5 0.2 0.0 0.0 0.0

mpht_1 0.2 7.9 15.5 10.8 15.0 26.6 15.3 41.9 17.0 26.2 6.9 2.4 3.4 0.0 0.0 0.0

anthron 1.5 2.3 4.9 4.6 2.0 8.8 0.9 33.5 10.9 9.9 9.0 0.5 0.4 0.0 0.6 0.0

m_9ant 0.2 1.0 0.9 0.3 0.4 0.3 0.4 1.2 0.9 1.2 0.2 0.1 0.0 0.0 0.0 0.0

nap2phen 0.1 5.4 9.4 4.4 4.6 11.7 9.3 23.0 4.0 17.6 6.2 0.7 0.0 0.0 0.0 0.0

anrquone 1.0 0.8 0.3 2.6 0.3 0.9 0.6 1.2 0.3 0.7 0.6 0.0 0.2 0.0 0.0 0.0

a_dmph 0.5 21.6 27.2 15.7 25.7 33.0 28.8 45.3 23.8 40.1 13.5 5.8 4.1 0.0 0.0 0.0

b_dmph 0.6 8.5 14.4 8.6 14.3 18.1 13.7 24.0 18.6 21.9 7.2 2.4 1.5 0.0 0.0 0.0

dm17ph 0.8 6.2 25.5 14.0 16.0 14.7 15.3 12.3 20.9 32.0 12.1 1.2 1.8 0.0 0.0 0.0

dm36ph 0.2 14.2 15.8 10.2 20.7 19.0 17.4 28.4 17.2 28.4 9.2 2.6 1.9 0.0 0.0 0.0

d_dmph 0.6 6.2 8.2 6.1 12.1 9.8 20.5 17.9 10.5 16.3 13.5 1.3 0.9 0.0 0.0 0.0

e_dmph 0.8 12.3 15.3 10.4 10.2 21.4 16.0 29.4 13.2 29.3 10.9 0.9 0.6 0.0 0.0 0.0
 

57 

TABLE 27 (CONT'D). LIGHT-DUTY VEHICLE FUELS AND LUBRICANTS POLYCYCLIC AROMATIC HYDROCARBONS, 

μg/g

(No Statistical Analyses Were Performed On These Data)

Test

Number LO-221459 LO-223292

LD-NE-FE0LD-NE-FE0-REP LD-NE-FE10LD-NE-AE0LD-NE-AE10LD-HE FE0LD-HE-FE10LD-HE-AE0LD-HE-AE10 EM-6314-F EM-6391-F EM-5574-F EM-6378-F EM-6802-F 

Emitter

Oil as 

received

Oil as 

received Normal Normal Normal Normal Normal High High High High NE & HE NE & HE NE & HE NE & HE NE & HE

Oil Fresh Aged Fresh Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A F&A F&A F&A

Fuel NA NA E0 E0 E10 E0 E10 E0 E10 E0 E10 E0 E10 Cold CO Cold E10

New Cold CO 

(E0)

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 72 20 20 20

Media Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel Fuel Fuel Fuel 

c_dmph 0.4 35.1 39.0 22.4 31.0 60.5 45.5 66.6 32.3 69.5 25.9 7.4 1.1 0.0 0.0 0.0

fluora 0.9 9.2 13.0 9.4 10.1 14.9 13.6 21.6 11.1 18.0 6.8 2.1 1.0 0.0 0.0 0.0

pyrene 5.7 15.4 23.8 19.8 28.3 30.6 28.5 55.9 50.6 52.1 15.6 2.3 2.5 0.0 0.0 0.0

antal9 2.3 3.6 4.6 2.1 3.8 3.7 3.1 3.7 5.2 8.0 1.9 0.0 0.2 0.0 0.0 0.0

retene 0.2 0.1 0.2 0.2 0.1 0.2 0.2 0.3 0.2 0.2 0.1 0.0 0.0 0.0 0.0 0.0

bafluo 0.4 4.0 11.8 6.9 10.6 18.1 14.6 11.5 6.8 30.6 4.8 0.9 0.6 0.0 0.0 0.0

bbfluo 0.9 5.5 9.2 0.8 7.9 10.9 8.7 16.0 8.4 12.3 4.7 0.9 0.6 0.0 0.0 0.0

bmpyfl 1.5 15.4 10.1 10.2 14.9 24.3 14.1 35.3 13.4 35.3 7.8 1.1 0.8 0.0 0.0 0.0

c1mflpy 0.6 9.8 12.0 12.0 12.1 20.2 21.4 33.1 14.2 28.9 8.9 1.5 0.5 0.0 0.0 0.0

m_13fl 1.7 7.4 8.5 3.1 4.6 10.6 14.3 35.4 13.2 35.4 7.7 0.3 0.8 0.0 0.0 0.0

m_4pyr 15.7 17.4 23.1 18.1 23.6 24.5 17.3 40.3 42.2 44.0 15.0 0.3 0.2 0.0 0.0 0.0

cmpyfl 1.7 10.4 15.7 9.4 15.0 20.7 18.2 29.8 15.7 22.9 8.7 1.8 1.1 0.0 0.0 0.0

dmpyfl 13.2 17.6 24.2 19.6 26.9 23.5 20.9 52.6 63.3 59.0 14.4 0.7 0.3 0.0 0.0 0.0

m_1pyr 11.4 14.3 15.0 12.2 13.2 18.4 13.2 34.8 30.2 36.2 11.8 0.2 0.2 0.0 0.0 0.0

bntiop 0.8 0.8 0.4 1.0 2.0 1.0 0.3 0.9 1.2 0.8 0.8 0.0 0.0 0.0 0.0 0.0

bzcphen 0.6 0.4 1.1 1.9 1.0 1.5 0.3 0.9 1.2 1.7 0.3 0.0 0.0 0.0 0.0 0.0

bghifl 3.3 2.2 0.5 3.0 1.7 0.9 0.7 0.8 0.5 1.3 2.3 0.0 0.0 0.0 0.0 0.0

phant9 1.0 0.3 0.2 0.5 0.4 0.1 0.3 0.2 0.3 0.1 0.1 0.0 0.0 0.0 0.0 0.0

cp_cdpyr 1.1 0.8 0.6 0.6 0.4 0.3 0.5 2.4 1.0 0.5 0.3 0.1 0.0 0.0 0.0 0.0

baanth 0.2 7.1 8.2 4.3 4.4 10.2 7.7 16.3 8.8 17.1 8.9 0.5 0.6 0.0 0.3 0.0

chr_tr 0.2 5.6 6.5 8.5 4.2 9.0 7.8 15.7 10.9 16.0 6.9 0.1 0.2 0.0 0.0 0.0

bzanthr 2.3 1.6 3.3 2.5 1.2 2.4 4.2 8.7 0.9 9.3 1.3 0.4 5.8 0.0 2.5 0.0

baa7_12 4.7 3.0 9.9 1.9 5.1 11.7 11.3 3.5 3.6 0.0 3.9 0.2 0.1 0.0 0.0 0.0

m_3chr 0.2 7.4 6.3 2.2 4.5 12.7 6.0 14.0 12.3 19.1 7.0 0.2 0.1 0.0 0.0 0.0

chry56m 0.3 6.3 0.0 0.0 0.0 0.0 0.0 10.3 7.3 13.2 0.3 0.0 0.0 0.0 0.0 0.0

m_7baa 0.9 1.3 3.0 2.6 2.7 3.6 2.6 4.1 0.9 1.1 1.4 0.0 0.0 0.0 0.0 0.0

dmban712 0.4 1.4 0.2 1.1 0.6 1.2 0.3 0.0 1.8 0.3 0.1 0.4 0.1 0.0 0.0 0.1
 

58 

TABLE 27 (CONT'D). LIGHT-DUTY VEHICLE FUELS AND LUBRICANTS POLYCYCLIC AROMATIC HYDROCARBONS, 

μg/g

(No Statistical Analyses Were Performed On These Data)

Test

Number LO-221459 LO-223292

LD-NE-FE0LD-NE-FE0-REP LD-NE-FE10LD-NE-AE0LD-NE-AE10LD-HE FE0LD-HE-FE10LD-HE-AE0LD-HE-AE10 EM-6314-F EM-6391-F EM-5574-F EM-6378-F EM-6802-F 

Emitter

Oil as 

received

Oil as 

received Normal Normal Normal Normal Normal High High High High NE & HE NE & HE NE & HE NE & HE NE & HE

Oil Fresh Aged Fresh Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A F&A F&A F&A

Fuel NA NA E0 E0 E10 E0 E10 E0 E10 E0 E10 E0 E10 Cold CO Cold E10

New Cold CO 

(E0)

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 72 20 20 20

Media Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel Fuel Fuel Fuel 

bbjkfl 0.8 0.8 0.6 0.8 0.3 1.7 1.4 0.9 0.9 1.4 1.2 0.2 0.2 0.0 0.0 0.1

bafl 0.3 0.3 0.4 0.6 0.2 0.2 0.2 0.2 0.2 0.2 0.1 0.0 0.0 0.0 0.0 0.0

bepyrn 0.6 6.4 5.3 2.5 3.2 8.7 6.8 6.3 0.8 7.1 4.1 0.0 0.1 0.0 0.0 0.0

bapyrn 0.5 5.0 5.8 3.3 2.7 8.4 6.1 6.9 0.8 13.1 5.6 0.1 0.1 0.0 0.0 0.0

peryle 0.2 0.5 1.1 0.5 0.3 1.5 1.8 0.5 0.3 1.9 0.3 0.1 0.0 0.1 0.0 0.0

m_7bpy 0.3 1.4 1.7 0.3 0.9 1.5 1.7 0.5 0.4 1.2 0.3 0.0 0.0 0.0 0.0 0.0

bpy910dih 0.8 1.4 0.6 0.9 0.4 1.0 3.6 0.5 0.9 1.0 0.0 0.0 0.0 0.0 0.0 0.0

incdfl 0.4 1.4 0.3 0.5 1.0 1.0 0.4 0.6 0.7 0.3 0.0 0.0 0.0 0.0 0.0 0.0

dbahacr 0.6 0.6 0.8 4.5 0.8 0.9 1.0 0.7 0.8 0.0 0.7 0.0 0.1 0.0 0.0 0.0

dbajacr 0.4 0.3 0.6 0.9 1.1 0.3 0.6 0.3 0.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0

in123pyr 0.6 0.4 0.9 1.5 0.7 1.2 0.5 0.4 0.4 2.0 0.1 0.0 0.0 0.0 0.0 0.0

dbahacan 2.8 1.6 0.8 2.3 0.8 0.8 1.2 2.4 1.3 0.0 1.4 0.0 0.0 0.0 0.0 0.0

dbajan 0.6 0.8 1.0 1.1 0.7 0.8 0.8 0.5 0.5 0.0 0.2 0.0 0.0 0.0 0.0 0.0

bbchr 0.8 0.5 0.3 1.2 1.4 0.7 0.4 0.4 1.0 0.0 0.6 0.0 0.0 0.0 0.0 0.0

pic 0.6 0.4 0.6 1.3 1.5 0.8 0.5 0.9 1.2 0.0 0.4 0.0 0.0 0.0 0.0 0.0

bghipe 0.6 9.1 8.5 4.6 1.8 15.5 13.3 10.2 2.7 19.3 3.2 0.1 0.1 0.0 0.0 0.0

anthan 0.3 0.4 0.4 0.6 0.7 0.5 0.4 0.5 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbalpyr 0.3 0.4 0.3 0.6 0.1 0.3 0.3 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

corone 0.2 0.5 1.0 0.0 0.2 2.0 0.6 0.0 0.5 0.0 0.0 0.0 0.0 0.0 0.1 0.0

dbaepyr 0.3 0.2 0.2 0.0 0.2 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbaipyr 0.1 0.1 0.1 0.0 0.2 0.1 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0

dbahpyr 0.1 0.3 0.0 0.0 0.2 0.2 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbbkfl 0.1 1.1 0.3 0.3 0.1 0.6 0.3 0.5 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 

59 

TABLE 28. POLYCYCLIC AROMATIC HYDROCARBONS SPECIES CODES

\

CODE SPECIE CODE SPECIE

NAPHTH naphthalene D_DMPH D-dimethylphenanthrene

QUINOLINE Quinoline E_DMPH E-dimethylphenanthrene

MNAPH2 2-methylnaphthalene C_DMPH C-dimethylphenanthrene

MNAPH1 1-methylnaphthalene FLUORA Fluoranthene

BIPHEN Biphenyl PYRENE Pyrene

M_2BPH 2-methylbiphenyl ANTAL9 9-Anthraaldehyde

DMN267 2,6+2,7-dimethylnaphthalene RETENE Retene

DM1367 1,3+1,6+1,7dimethylnaphth BAFLUO benzo(a)fluorene

D14523 1,4+1,5+2,3-dimethylnaphth BBFLUO benzo(b)fluorene

ENAP12 1+2ethylnaphthalene BMPYFL B-MePy/MeFl

ACNAPY Acenaphthylene C1MFLPY 1-MeFl+C-MeFl/Py

DMN12 1,2-dimethylnaphthalene M_13FL 1+3-methylfluoranthene

DMN18 1,8-dimethylnaphthalene M_4PYR 4-methylpyrene

ACNAPE Acenaphthene CMPYFL C-MePy/MeFl

M_3BPH 3-methylbiphenyl DMPYFL D-MePy/MeFl

M_4BPH 4-methylbiphenyl M_1PYR 1-methylpyrene

DBZFUR Dibenzofuran BNTIOP Benzonaphthothiophene

EM_12N 1-ethyl-2-methylnaphthalene BZCPHEN benzo(c)phenanthrene

TMI235N 2,3,5+I-trimethylnaphthalene BGHIFL Benzo(ghi)fluoranthene

BTMNAP B-trimethylnaphthalene PHANT9 9-phenylanthracene

ATMNAP A-trimethylnaphthalene CP_CDPYR Cyclopenta(c,d)pyrene

CTMNAP C-trimethylnaphthalene BAANTH Benz(a)anthracene

EM_21N 2-ethyl-1-methylnaphthalene CHR_TR Chrysene-Triphenylene

ETMNAP E-trimethylnaphthalene BZANTHR Benzanthrone

TM245N 2,4,5-trimethylnaphthalene BAA7_12 Benz(a)anthracene-7,12-dione

FTMNAP F-trimethylnaphthalene M_3CHR 3-methylchrysene

FLUORE Fluorene CHRY56M 5+6-methylchrysene

TM145N 1,4,5-trimethylnaphthalene M_7BAA 7-methylbenz(a)anthracene

JTMNAP J-trimethylnaphthalene DMBAN712 7,12-dimethylbenz(a)anthracene

A_MFLUO A-Methylfluorene BBJKFL Benzo(b+j+k)fluoranthene

B_MFLUO B-Methylfluorene BAFL Benzo(a)fluoranthene

M_1FLUO 1-Methylfluorene BEPYRN BeP

FL9ONE 9-fluorenone BAPYRN BaP

DBTH Dibenzothiophene PERYLE Perylene

PHENAN Phenanthrene M_7BPY 7-methylbenzo(a)pyrene

ANTHRA Anthracene

XANONE Xanthone

ACQUONE Acenaphthenequinone INCDFL Indeno[123-cd]fluoranthene

M_2PHEN 3-methylphenanthrene DBAHACR dibenz(a,h)acridine

M_3PHEN 2-methylphenanthrene DBAJACR dibenz(a,j)acridine

PNAPONE Perinaphthenone IN123PYR Indeno[123-cd]pyrene

M_2ANTH 2-methylanthracene DBAHACAN Dibenzo(ah+ac)anthracene

M_45PHEN 4,5-methylenephenanthrene DBAJAN Dibenzo(a,j)anthracene

M_9PHEN 9-methylphenanthrene BBCHR Benzo(b)chrysene

MPHT_1 1-methylphenanthrene PIC Picene

ANTHRON Anthrone BGHIPE Benzo(ghi)perylene

M_9ANT 9-methylanthracene ANTHAN Anthanthrene

NAP2PHEN 2-phenylnaphthalene DBALPYR Dibenzo(a,l)pyrene

ANRQUONE Anthraquinone CORONE Coronene

A_DMPH A-dimethylphenanthrene DBAEPYR Dibenzo(a,e)pyrene

B_DMPH B-dimethylphenanthrene DBAIPYR Dibenzo(a,i)pyrene

DM17PH 1,7-dimethylphenanthrene DBAHPYR Dibenzo(a,h)pyrene

DM36PH 3,6-dimethylphenanthrene DBBKFL Dibenzo(b,k)fluoranthene

BPY910DIH

9,10-dihydrobenzo(a)pyrene-7(8H)-

one
60 

TABLE 29. LIGHT-DUTY VEHICLE AVERAGE ALKANES IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NE-FE0-72

LD-NEF-E0-

72-3a

LD-NEF-E0-20

LD-NEF-E10-

72

LD-NEF-E10-

20

LD-NEA-E0-72LD-NEA-E0-20

LD-NEA-E10-

72

LD-NEA-E10-

20

LD-HEF-E0-72LD-HEF-E0-20

LD-HEF-E10-

72

LD-HEF-E10-

20

LD-HEA-E0-72LD-HEA-E0-20

LD-HEA-E10-

72

LD-HEA-E10-

20

Source Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High 

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged 

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp, °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Mediab F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD 

TB 

Correctionc Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

dodec 0 0 6 3 19 0 12 9 5 15 15 73 22 22 42 79 30

norfarn 0 0 0 1 1 0 0 4 0 4 3 31 7 5 7 34 9

tridec 0 0 1 0 1 0 2 1 2 14 11 53 24 21 25 58 23

hpycyhx 0 0 0 0 1 0 0 0 0 7 3 2 5 3 5 2 2

farnes 0 0 0 0 1 0 0 0 0 1 2 4 2 2 9 4 4

tdec 0 0 2 0 7 0 1 0 0 17 15 25 19 18 26 26 17

ocycyhx 0 0 0 0 0 0 0 0 0 1 2 1 1 1 2 1 3

pentad 0 0 1 0 2 0 1 0 0 11 14 14 15 17 20 10 10

noycyhx 0 0 0 0 0 0 0 0 0 3 2 3 4 5 4 3 3

hexad 0 0 1 0 2 0 2 0 1 32 30 30 31 28 30 25 20

norprst 0 0 0 0 1 0 0 0 0 4 3 4 3 3 4 1 1

decyhx 0 0 0 0 0 0 0 0 0 2 2 1 1 1 2 1 1

heptad 0 0 1 0 2 0 2 0 1 23 22 23 26 19 26 14 11

heptdpris 0 0 1 0 1 0 1 0 0 10 11 10 11 9 8 6 4

dec1yhx 0 0 0 0 0 0 0 0 0 3 3 4 7 3 3 2 2

octad 0 0 1 0 1 0 1 0 0 41 52 56 48 43 52 38 29

phytan 0 0 0 0 1 0 0 0 0 15 13 15 15 8 9 2 3

dec2yhx 0 0 0 0 0 0 0 0 0 3 3 3 3 1 2 1 2

nonad 0 0 1 0 1 0 1 0 0 24 23 24 26 18 22 12 9

dec3yhx 0 0 0 0 1 0 0 0 0 2 3 3 5 2 3 2 0

eicosa 0 0 2 0 1 0 1 0 1 46 63 65 60 54 66 47 36

dec4yhx 0 0 0 0 0 0 0 0 0 6 7 7 7 3 4 1 2

heneic 0 0 7 0 4 0 6 0 3 29 32 40 31 28 31 17 18

dec5yhx 0 0 0 0 0 0 0 0 0 19 18 21 20 15 16 12 6

docosa 0 0 17 0 9 0 15 0 9 49 78 96 72 63 70 51 44
61 

TABLE 29 (CONT'D). LIGHT-DUTY VEHICLE AVERAGE ALKANES IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NEF-E0-72

LD-NEF-E0-

72-3a

LD-NEF-E0-20

LD-NEF-E10-

72

LD-NEF-E10-

20

LD-NEA-E0-72LD-NEA-E0-20

LD-NEA-E10-

72

LD-NEA-E10-

20

LD-HEF-E0-72LD-HEF-E0-20

LD-HEF-E10-

72

LD-HEF-E10-

20

LD-HEA-E0-72LD-HEA-E0-20

LD-HEA-E10-

72

LD-HEA-E10-

20

Source Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate Particulate

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged 

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10

Temp, °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Mediab F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD 

TB 

Correctionc Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

dec6yhx 0 0 0 0 0 0 0 0 0 2 3 21 16 2 3 2 2 

tricosa 0 0 44 1 26 0 40 1 25 60 102 140 93 63 51 36 40

dec7yhx 0 0 5 0 4 2 6 1 11 35 47 57 55 52 50 32 30

tetcos 1 0 91 1 49 0 81 0 47 112 191 270 179 124 98 76 86

dec8yhx 0 0 0 0 0 0 0 0 0 8 10 11 29 12 9 7 3

pencos 1 0 179 1 98 0 161 0 92 98 255 350 230 52 74 72 71

hexcos 2 0 250 6 145 0 119 2 133 140 302 488 97 161 65 94 107

dec9yhx 0 0 0 0 0 0 0 0 0 1 37 61 42 26 21 8 19

hepcos 0 0 249 0 142 0 236 0 134 351 588 932 665 470 180 296 219

cyhxeic 0 0 0 0 0 0 0 0 0 17 18 2 18 15 13 16 2

octcos 1 0 257 0 146 0 231 0 136 251 478 772 517 412 138 197 155

noncos 1 0 272 0 154 0 225 0 139 211 397 685 482 341 83 171 130

cyhxhen 0 0 3 0 1 0 2 0 1 10 19 21 21 17 23 14 14

tricont 2 0 218 2 126 0 187 2 114 130 323 451 255 131 76 68 78

htricont 2 0 221 1 123 0 158 0 112 103 305 419 221 97 54 49 59

dtricont 0 0 140 0 80 0 78 0 67 45 185 260 136 62 22 23 30

ttricont 0 0 88 0 53 0 34 0 43 32 124 154 96 35 15 12 15

tetricont 0 0 42 0 28 0 8 0 22 19 62 85 50 14 6 5 14

ptricont 0 0 22 0 17 0 0 0 13 8 46 50 28 9 1 1 2

hxtricont 0 0 10 1 10 0 0 0 7 7 30 39 25 10 0 0 2

hptricont 0 0 4 0 5 0 0 0 4 6 25 32 18 3 0 0 1 

otricont 0 0 2 0 2 0 0 0 1 1 12 17 10 1 0 0 0

ntricont 0 0 2 0 1 0 0 0 1 0 7 10 1 0 0 0 0 

tecont 0 0 1 0 0 0 0 0 1 0 1 8 1 0 0 0 0

hxtric74 0.03 0.02 0.17 0.02 0.05 0.01 0.03 0.02 0.07 220 219 408 482 411 574 402 420

UCM 1852 0 1721 123 344 0 273 126 250 41877 39787 43084 41254 35579 42630 33152 29508 a The repeat test of the normal emitter after all other tests were run is included here but not as part of the first two test's averaged data. b Filter and XAD cartridge samples

c Test samples were corrected by subtracting a tunnel blank measurement
62 

TABLE 30. ALKANES SPECIES CODES 

CODE SPECIE

Alkanes

DODEC Dodecane

NORFARN norfarnesane

TRIDEC Tridecane

HPYCYHX Heptylcyclohexane

FARNES farnesane

TDEC Tetradecane

OCYCYHX Octylcyclohexane

PENTAD pentadecane

NOYCYHX Nonylcyclohexane

HEXAD Hexadecane

NORPRST Norpristane

DECYHX Decylcyclohexane

HEPTAD Heptadecane

HEPTDPRIS Pristane

DEC1YHX Undecylcyclohexane

OCTAD octadecane

PHYTAN phytane

DEC2YHX Dodecylcyclohexane

NONAD nonadecane

DEC3YHX Tridecylcyclohexane

EICOSA eicosane

DEC4YHX Tetradecylcyclohexane

HENEIC heneicosane

DEC5YHX Pentadecylcyclohexane

DOCOSA docosane

DEC6YHX Hexadecylcyclohexane

TRICOSA tricosane

DEC7YHX Heptadecylcyclohexane

TETCOS tetracosane

DEC8YHX Octadecylcyclohexane

PENCOS Pentacosane

HEXCOS Hexacosane

DEC9YHX Nonadecylcyclohexane

HEPCOS Heptacosane

CYHXEIC Eicosylcyclohexane

OCTCOS Octacosane

NONCOS Nonacosane

CYHXHEN Heneicosylcyclohexane

TRICONT Triacontane

HTRICONT Hentriacontane

DTRICONT Dotriacontane

TTRICONT Tritriacontane

TETRICONT Tetratriacontane

PTRICONT Pentatriacontane

HXTRICONT Hexatriacontane

HPTRICONT Heptatriacontane

OTRICONT Octatriacontane

NTRICONT Nonatriacontane

TECONT Tetracontane

HXTRIC74 Hexatriacontane-d74

UCM Unresolved Complex Mixture
63 

TABLE 31. LIGHT-DUTY VEHICLE ALKANES IN FUELS AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test

Number

LO221459LO223292

LDNE-FE0

LDNE-FE0-

REP

LDNE-FE10LDNE-AE0LDNE-AE10LDHE-FE0LDHE-FE10LDHE-AE0LDHE-AE10 EM_6314_F EM_6391_F EM_5574_F EM_6378_F EM_6802_F

Sample Type Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel Fuel Fuel Fuel

Emitter NA NA Normal Normal Normal Normal Normal High High High High NE & HE NE & HE NE & HE NE & HE NE & HE

Oil Fresh Aged Fresh Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A F&A F&A F&A

Fuel NA NA E0 E0 E10 E0 E10 E0 E10 E0 E10 E0 E10 Cold CO Cold E10

New Cold 

CO (E0)

Temp, °F 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 72 20 20 20

Tracera No No Yes Yes Yes Yes Yes Yes Yes Yes Yes No No No No No

dodec 0 40 4 3 13 13 20 37 12 15 16 47 320 29 33 58

norfarn 0 6 1 1 4 0 2 1 0 2 8 5 167 0 1 4

tridec 2 59 10 18 55 19 45 12 24 17 24 35 292 6 7 23

hpycyhx 0 2 0 0 1 0 1 0 1 0 0 0 9 0 0 0

farnes 0 1 0 0 2 0 1 0 2 2 3 0 4 0 0 2

tdec 1 25 8 7 47 7 21 6 19 16 17 6 52 1 3 16

ocycyhx 0 0 0 0 1 0 1 0 0 0 1 0 0 0 0 0

pentad 13 16 7 13 43 7 9 5 8 15 6 2 6 1 1 10

noycyhx 4 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0

hexad 49 17 32 41 86 24 15 20 21 23 13 11 9 5 5 12

norprst 31 4 7 14 18 3 1 8 9 5 5 0 0 0 0 0

decyhx 10 0 4 3 2 1 0 1 2 1 0 0 0 0 0 0

heptad 121 36 71 116 154 36 14 47 51 32 23 1 1 1 0 2

heptdpris 41 11 21 31 56 7 9 25 27 13 9 1 0 1 0 1

dec1yhx 26 3 15 18 13 1 2 10 6 2 1 2 1 0 1 0

octad 173 60 109 131 154 61 45 76 75 50 39 14 6 8 7 10

phytan 96 26 63 81 74 17 19 57 63 28 19 0 0 0 0 2

dec2yhx 49 7 20 22 27 3 2 23 17 3 2 0 0 0 0 0

nonad 157 115 100 107 160 81 79 95 101 72 65 0 4 1 1 0

dec3yhx 42 13 31 35 36 5 3 26 20 7 11 1 0 0 0 0

eicosa 181 176 118 106 159 119 101 103 117 99 99 8 7 6 6 8

dec4yhx 28 9 15 14 19 19 5 34 32 19 25 0 0 0 0 0

heneic 153 196 119 114 156 156 119 111 112 122 121 0 1 0 0 0

dec5yhx 216 141 130 116 131 108 93 107 94 79 98 1 0 0 0 0

docosa 280 213 179 73 161 173 190 140 152 174 158 8 5 7 7 5

dec6yhx 27 15 70 74 34 74 52 13 10 11 53 0 0 0 0 0
64 

TABLE 31 (CONT'D). LIGHT-DUTY VEHICLE ALKANES IN FUELS AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test

Number

LO221459LO223292

LDNE-FE0

LDNE-FE0-

REP

LDNE-FE10LDNE-AE0LDNE-AE10LDHE-FE0LDHE-FE10LDHE-AE0LDHE-AE10 EM_6314_F EM_6391_F EM_5574_F EM_6378_F EM_6802_F

Sample Type Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel Fuel Fuel Fuel

Emitter NA NA Normal Normal Normal Normal Normal High High High High NE & HE NE & HE NE & HE NE & HE NE & HE

Oil Fresh Aged Fresh Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A F&A F&A F&A

Fuel NA NA E0 E0 E10 E0 E10 E0 E10 E0 E10 E0 E10 Cold CO Cold E10

New Cold 

CO (E0)

Temp, °F 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 72 20 20 20

Tracera No No Yes Yes Yes Yes Yes Yes Yes Yes Yes No No No No No

tricosa 265 197 221 221 186 204 254 172 251 284 269 3 1 2 0 0

dec7yhx 629 90 304 336 45 305 270 290 11 239 272 0 0 0 0 0

tetcos 425 63 397 405 361 369 276 279 357 163 348 7 4 6 4 7

dec8yhx 273 29 3 34 35 122 34 37 85 50 53 0 0 0 0 0

pencos 177 77 693 661 866 843 443 997 443 357 839 3 1 1 2 0

hexcos 303 222 78 123 152 998 281 397 602 361 417 5 5 3 3 2

dec9yhx 107 11 10 90 10 199 30 4 17 15 211 1 1 1 0 0

hepcos 72 90 253 187 133 1195 1004 1059 1310 1500 802 1 1 1 1 1

cyhxeic 60 7 57 193 80 41 199 116 28 21 29 0 0 0 0 0

octcos 199 160 143 973 744 1106 852 1113 671 723 696 4 5 1 2 1

noncos 226 162 623 777 678 997 662 450 113 208 408 1 1 3 2 0

cyhxhen 16 40 20 173 67 83 66 206 7 136 201 0 0 0 0 0

tricont 153 165 536 463 499 372 503 170 202 143 125 4 3 3 2 1

htricont 113 169 133 316 296 202 87 106 74 143 88 1 0 1 3 0

dtricont 49 256 101 57 37 15 39 20 51 34 32 1 5 2 3 2

ttricont 38 53 45 15 25 64 4 14 5 4 8 2 2 1 1 0

tetricont 139 22 4 21 8 14 4 8 9 10 14 3 2 1 1 1

ptricont 11 8 4 3 7 3 8 2 1 1 3 2 1 1 0 0

hxtricont 6 9 20 14 11 11 11 1 1 1 3 6 6 3 4 0

hptricont 3 3 4 2 4 9 2 1 3 1 3 5 3 7 5 1

otricont 1 1 2 3 5 2 3 1 0 0 1 5 5 4 5 0

ntricont 6 7 3 4 7 2 4 3 2 1 1 3 4 4 7 0

tecont 5 2 3 2 2 3 3 2 1 1 2 4 0 1 2 1

hxtric74 1 2 523 2042 702 714 570 387 874 725 2451 0 0 0 0 0

UCM 742508 451766 537779 634536 660285 527735 553354 208139 219961 218711 211950 1525 1307 1342 1516 493

a Tracer refers to whether the Hexatriaconte tracer was added to the lubricant.
65 

7.5.2.5 Hopanes and Steranes

 PM and SVOCs sampled from the light-duty tests were also analyzed by DRI for hopanes 

and steranes. Table 32 shows the average results in μg/mile of the replicate tests performed in 

each configuration. Table 33 shows the codes for the hopanes and steranes species in Table 32. 

Hopanes and steranes were also measured by DRI in the fuels and lubricants used in the 

study. These data are shown in Table 34 in units of μg/gram of lubricant or fuel. The first two 

columns of data in Table 34 are results of the analyses of the fresh and aged lubricants before 

mixing with the hexatriacontane tracer. The following nine columns of data are from lubricant 

samples taken after the replicate emission tests were performed. The final seven columns are 

data from fuel analyses and two replicate analyses.

Because higher levels of hopanes and steranes were found in the light-duty fuels than 

expected, NREL funded a small study to measure hopanes and steranes in additional commercial 

fuels. DRI was tasked to collect samples of regular gasoline, premium gasoline, and diesel fuels 

from three locations in Reno, Nevada. DRI then analyzed the fuel samples for hopanes and 

steranes. The results are shown in Appendix D. The Reno fuels are compared to the CLOSE 

Project fuels in Figures D1 and D2 for gasoline and diesel fuels, respectively. Figure D1 shows 

that the CLOSE Project light-duty fuels are very different in hopane and sterane content than the 

commercial gasolines from Nevada. The differences between the CLOSE and Reno gasolines 

may be because the CLOSE fuels are blended to meet stringent specifications with a variety of 

blend fuels that are not expected in commercial fuels. Figure D2 shows that the TxLED diesel 

and B20 diesel are similar to the Nevada diesels.

7.5.2.6 Particulate-Phase Elemental and Organic Carbon

 PM sampled from the light-duty tests were also analyzed by DRI for elemental carbon 

and organic carbon (EC/OC). Table 35 shows the average results in μg/mile of the replicate tests 

performed in each configuration. The configurations are identified in the five left columns of the 

table, and EC/OC results are shown in the three right columns. In Table 35, EC is elemental 

carbon measured, OC is organic carbon, and TC is total carbon. 

7.5.2.7 Particulate-Phase Sulfates

 PM sampled from the light-duty tests were also analyzed by DRI for sulfates. Table 36 

shows the average results in μg/mile of the replicate tests performed in each configuration.

7.5.2.8 Particulate-Phase Soluble Organic Fraction 

 PM sampled from the light-duty tests were also analyzed by DRI for soluble organic 

fraction (SOF). Table 37 shows the average results for the normal emitter and high emitter, in 

percent SOF, of the replicate tests performed in each configuration.
66 

TABLE 32. LIGHT-DUTY VEHICLE HOPANES AND STERANES IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

LD-NEF-E0-72

LD-NEF-E0-

72-3a

LD-NEF-E0-20

LD-NEF-E10-

72

LD-NEF-E10-

20

LD-NEA-E0-72LD-NEA-E0-20

LD-NEA-E10-

72

LD-NEA-E10-

20

LD-HEF-E0-72LD-HEF-E0-20

LD-HEF-E10-

72

LD-HEF-E10-

20

LD-HEA-E0-72LD-HEA-E0-20

LD-HEA-E10-

72

LD-HEA-E10-

20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel E0 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 E0 E0 E10 E10 

Temp, °F 72 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20 

Mediab F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD

TB 

Correctionc Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

hop15 0.002 0.009 0.107 0.022 0.086 0.014 0.141 0.008 0.206 3.182 2.278 1.976 1.979 2.348 2.136 1.636 1.710

hop17 0.015 0.014 0.115 0.020 0.032 0.020 0.187 0.024 0.094 21.172 16.408 14.874 14.299 15.123 12.865 10.211 10.355

hop19 0.008 0.000 0.104 0.013 0.021 0.004 0.129 0.007 0.053 9.037 7.049 6.271 6.036 6.361 5.401 4.307 4.303

hop20 0.003 0.000 0.047 0.005 0.004 0.011 0.041 0.011 0.024 0.227 0.256 0.079 0.148 0.515 0.288 0.292 0.348

hop21 0.011 0.000 0.072 0.003 0.038 0.002 0.077 0.003 0.062 6.184 4.735 4.034 4.095 4.274 3.377 2.885 3.024

hop22 0.000 0.000 0.057 0.001 0.018 0.000 0.047 0.001 0.052 4.896 4.308 3.207 3.414 3.613 2.834 2.479 2.471

hop23 0.003 0.000 0.003 0.001 0.004 0.000 0.004 0.000 0.000 0.333 0.474 0.366 0.186 0.375 0.323 0.154 0.183 

hop24 0.003 0.000 0.015 0.004 0.000 0.000 0.043 0.000 0.000 3.161 2.735 2.239 2.248 2.169 1.869 1.534 1.636 

hop25 0.005 0.000 0.022 0.005 0.000 0.000 0.021 0.001 0.009 1.991 1.585 1.279 1.331 1.425 1.245 0.918 1.157 

hop26 0.003 0.000 0.013 0.003 0.012 0.001 0.016 0.001 0.012 1.718 1.259 1.002 1.049 1.057 0.845 0.836 0.790 

hop27 0.003 0.000 0.015 0.002 0.002 0.000 0.043 0.006 0.008 0.828 0.809 0.495 0.479 0.493 0.367 0.420 0.446

ster42 0.008 0.001 0.038 0.005 0.016 0.002 0.034 0.003 0.006 1.373 1.077 0.856 0.892 0.970 0.975 0.776 0.715

ster43 0.006 0.001 0.025 0.006 0.018 0.003 0.082 0.006 0.010 5.237 3.977 3.482 3.405 3.393 3.146 2.442 2.337

ster44 0.002 0.002 0.057 0.005 0.007 0.002 0.004 0.004 0.028 2.301 1.773 1.535 1.590 1.689 1.573 1.202 1.050

ster45_40 0.001 0.000 0.102 0.002 0.200 0.003 0.315 0.001 0.106 4.671 3.623 3.106 3.259 2.690 2.503 2.416 1.389

ster46 0.005 0.000 0.021 0.000 0.011 0.000 0.024 0.000 0.006 1.044 0.873 0.622 0.697 0.638 0.620 0.465 0.434 

ster47 0.002 0.001 0.038 0.002 0.013 0.001 0.049 0.002 0.020 1.416 1.112 0.763 0.879 1.099 1.166 0.915 0.844 

ster48_41 0.004 0.001 0.060 0.003 0.064 0.006 0.069 0.004 0.030 3.698 2.948 2.430 2.403 2.755 2.075 1.397 1.819 

ster49 0.007 0.021 0.013 0.006 0.045 0.004 0.027 0.006 0.020 0.694 0.529 0.230 0.425 0.666 0.515 0.371 0.200 

ster50 0.000 0.000 0.020 0.002 0.001 0.000 0.018 0.002 0.000 0.708 0.469 0.444 0.445 0.255 0.303 0.401 0.442 

ster51 0.001 0.000 0.034 0.003 0.006 0.000 0.035 0.001 0.016 1.798 1.404 1.123 1.098 1.197 1.017 0.766 0.811

ster52 0.001 0.000 0.022 0.002 0.006 0.001 0.028 0.003 0.013 1.330 0.946 0.834 0.803 0.935 0.773 0.722 0.607

ster53 0.002 0.000 0.021 0.000 0.000 0.000 0.025 0.001 0.011 0.873 0.764 0.550 0.575 0.604 0.540 0.429 0.470 a The repeat test of the normal emitter after all other tests were run is included here but not as part of the first two test's averaged data. b Filter and XAD cartridge samples

c Test samples were corrected by subtracting a tunnel blank measurement
67 

TABLE 33. HOPANES AND STERANES SPECIES CODES

Code Specie

hop15 17α(H)-22,29,30-Trisnorhopane

hop17 17α(H),21ß(H)-29-Norhopane

hop19 17α(H),21ß(H)-Hopane

hop20 17ß(H),21α(H)-Hopane

hop21 22S-17α(H),21ß(H)-30-Homohopane

hop22 22R-17α(H),21ß(H)-30-Homohopane

hop23 17ß(H),21ß(H)-Hopane

hop24 22S-17α(H),21ß(H)-30,31-Bishomohopane

hop25 22R-17α(H),21ß(H)-30,31-Bishomohopane

hop26 22S-17α(H),21ß(H)-30,31,32-Trishomohopane

hop27 22R-17α(H),21ß(H)-30,31,32-Trishomohopane

ster42 20S-5α(H),14α(H),17α(H)-cholestane

ster43 20R-5α(H),14ß(H),17ß(H)-cholestane

ster44 20S-5α(H),14ß(H),17ß(H)-cholestane

ster45_40 20R-5α(H),14α(H),17α(H)-cholestane & 20S-13ß(H),17α(H)-diastigmastane

ster46 20S-5α(H),14α(H),17α(H)-ergostane 

ster47 20R-5α(H),14ß(H),17ß(H)-ergostane

ster48_41 20S-5α(H),14ß(H),17ß(H)-ergostane & 20R-13α(H),17ß(H)-diastigmastane

ster49 20R-5α(H),14α(H),17α(H)-ergostane

ster50 20S-5α(H),14α(H),17α(H)-stigmastane

ster51 20R-5α(H),14ß(H),17ß(H)-stigmastane

ster52 20S-5α(H),14ß(H),17ß(H)-stigmastane

ster53 20R-5α(H),14α(H),17α(H)-stigmastane
68 

TABLE 34. LIGHT-DUTY VEHICLE HOPANES AND STERANES IN FUELS AND LUBRICANTS, μg/g

(No Statistical Analyses Were Performed On These Data)

Sample

Code

LO221459LO223292LD-NE-FE0LD-NE-FE0-REPLD-NEF-E10LD-NEA-E0LD-NEA-E10LD-HEF-E0LD-HEF-E10LD-HEA-E0LD-HEA-E10EM_6314

_F

EM_6391

_F

EM_5574_

F

EM_6378

_F

EM_6802

_F

EM_5574

_F

EM_6378_

F

Sample Type Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel Fuel Fuel Fuel 

Fuel, 

replicate 

Fuel, 

replicate 

Emitter NA NA Normal Normal Normal Normal Normal High High High High NE & HE NE & HE NE & HE NE & HE NE & HE NE & HE NE & HE

Oil Fresh Aged Fresh Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A F&A F&A F&A F&A F&A

Fuel NA NA E0 E0 E10 E0 E10 E0 E10 E0 E10 E0 E10 Cold CO Cold E10

New Cold 

CO (E0)

Original 

Cold CO Cold E10

Temp, °F 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 72 20 20 20 20 20

Tracera No No Yes Yes Yes Yes Yes Yes Yes Yes Yes No No No No No No No

hop15 3.89 4.63 5.03 6.17 6.61 5.57 4.89 6.64 7.68 5.73 5.76 0.04 0.03 0.00 0.00 0.02 0.00 0.00

hop17 19.27 20.96 25.22 26.25 31.84 24.89 23.03 29.57 34.29 24.27 26.33 0.09 0.18 0.13 0.14 0.10 0.13 0.13

hop19 8.63 9.02 11.57 11.45 14.32 11.57 10.70 13.96 15.18 11.12 12.47 0.12 0.13 0.08 0.06 0.07 0.08 0.07

hop20 0.48 0.31 0.67 0.71 1.24 0.62 0.55 0.57 1.16 0.49 0.54 0.03 0.04 0.00 0.00 0.08 0.00 0.00

hop21 6.05 6.12 7.73 8.44 10.02 8.10 7.54 9.81 10.36 7.94 8.35 0.20 0.21 0.00 0.14 0.20 0.00 0.14

hop22 4.90 5.51 6.38 7.16 8.54 6.82 5.98 8.02 9.02 6.00 7.42 0.00 0.15 0.00 0.00 0.14 0.00 0.00

hop23 0.00 0.32 0.12 0.00 0.00 0.00 0.00 0.36 0.10 0.00 0.28 0.00 0.00 0.00 0.00 0.00 0.00 0.00

hop24 3.27 3.94 4.63 5.25 5.70 5.36 4.35 6.18 6.35 4.70 5.30 0.00 0.06 0.00 0.00 0.00 0.00 0.00

hop25 2.51 2.55 3.46 3.38 4.02 3.18 2.97 4.27 4.67 3.09 3.27 0.16 0.00 0.00 0.00 0.00 0.00 0.00

hop26 1.87 1.91 2.36 2.63 3.02 2.83 2.48 3.42 3.00 2.40 2.97 0.00 0.00 0.09 0.00 0.00 0.09 0.00

hop27 1.15 1.16 1.47 1.72 1.58 1.53 1.51 2.07 1.88 1.45 1.75 0.00 0.00 0.00 0.15 0.00 0.00 0.15

ster42 1.95 2.17 2.57 2.12 2.80 2.07 1.77 2.79 2.78 2.17 2.85 0.09 0.09 0.09 0.11 0.02 0.10 0.10

ster43 6.33 6.22 6.12 5.86 8.64 6.33 5.99 8.22 9.72 7.17 7.79 0.02 0.04 0.02 0.04 0.01 0.02 0.03

ster44 2.65 2.72 2.63 3.15 3.96 3.04 2.89 3.19 3.90 3.03 2.42 0.01 0.10 0.05 0.05 0.00 0.04 0.05

ster45_40 4.89 4.00 5.29 5.16 6.95 4.62 4.55 5.84 7.26 5.68 5.09 0.06 0.05 0.07 0.12 0.00 0.10 0.09

ster46 1.53 1.53 1.56 1.50 1.86 1.58 1.37 1.94 1.89 2.12 1.92 0.02 0.00 0.00 0.00 0.00 0.00 0.00

ster47 1.52 1.40 1.80 1.53 1.96 1.63 1.48 1.88 2.18 2.41 1.92 0.02 0.02 0.01 0.03 0.00 0.02 0.03

ster48_41 5.74 6.13 6.74 6.04 7.08 5.44 5.29 6.68 8.22 6.81 7.20 0.03 0.11 0.05 0.00 0.00 0.05 0.00

ster49 1.25 1.27 1.59 1.60 1.88 1.42 1.36 1.60 1.88 1.56 1.81 0.03 0.02 0.02 0.00 0.00 0.02 0.00

ster50 1.54 1.48 1.51 1.64 2.03 1.63 1.49 1.77 1.93 1.96 1.80 0.00 0.05 0.00 0.00 0.03 0.00 0.00

ster51 2.31 2.36 2.25 2.36 3.07 2.44 2.17 2.81 3.63 2.89 3.19 0.02 0.09 0.00 0.05 0.02 0.00 0.06

ster52 1.66 1.73 2.54 1.80 2.39 2.23 1.68 2.69 2.57 2.37 2.18 0.03 0.03 0.02 0.02 0.00 0.02 0.02

ster53 1.15 1.22 1.29 1.10 1.46 1.14 1.15 1.40 1.65 1.26 1.49 0.04 0.04 0.01 0.03 0.02 0.01 0.03

a Tracer refers to whether the Hexatriaconte tracer was added to the lubricant.
69 

TABLE 35. LIGHT-DUTY ELEMENTAL CARBON AND ORGANIC CARBON

(No Statistical Analyses Were Performed On These Data)

Test Number Emitter Oil Fuel Temp, °F

EC

μg/mile

OC

μg/mile

TC

μg/mile

LD-NE-F-E0-72 Normal Fresh E0 72 142 39 181

LD-NE-F-E0-72-3a Normal Fresh E0 72 599 61 660

LD-NE-F-E0-20 Normal Fresh E0 20 2254 409 2663

LD-NE-F-E10-72 Normal Fresh E10 72 1100 104 1204

LD-NE-F-E10-20 Normal Fresh E10 20 3710 473 4184

LD-NE-A-E0-72 Normal Aged E0 72 668 52 720

LD-NE-A-E0-20 Normal Aged E0 20 3095 388 3483

LD-NE-A-E10-72 Normal Aged E10 72 1361 118 1478

LD-NE-A-E10-20 Normal Aged E10 20 3455 377 3832

LD-HE-F-E0-72 High Fresh E0 72 1487 79095 80582

LD-HE-F-E0-20 High Fresh E0 20 2172 71723 73895

LD-HE-F-E10-72 High Fresh E10 72 953 63304 64257

LD-HE-F-E10-20 High Fresh E10 20 7823 68629 76452

LD-HE-A-E0-72 High Aged E0 72 1527 55760 57286

LD-HE-A-E0-20 High Aged E0 20 7429 73217 80646

LD-HE-A-E10-72 High Aged E10 72 2141 50997 53138

LD-HE-A-E10-20 High Aged E10 20 2606 44587 47193

a The repeat test of the normal emitter after all other tests were run is included here but not as part of the 

first two test's averaged data.

TABLE 36. AVERAGE SULFATE EMISSIONS FROM LIGHT-DUTY VEHICLES

(No Statistical Analyses Were Performed On These Data)

Test Number Emitter Oil Fuel Temp

Average Sulfate 

(μg/mile)

LD-NE-F-E0-72 Normal Fresh E0 72 5.02

LD-NE-F-E0-72-3a Normal Fresh E0 72 7.88

LD-NE-F-E0-20 Normal Fresh E0 20 30.9

LD-NE-F-E10-72 Normal Fresh E10 72 40.3

LD-NE-F-E10-20 Normal Fresh E10 20 51.5

LD-NE-A-E0-72 Normal Aged E0 72 5.91

LD-NE-A-E0-20 Normal Aged E0 20 32.4

LD-NE-A-E10-72 Normal Aged E10 72 17.5

LD-NE-A-E10-20 Normal Aged E10 20 32.9

LD-HE-F-E0-72 High Fresh E0 72 571

LD-HE-F-E0-20 High Fresh E0 20 682

LD-HE-F-E10-72 High Fresh E10 72 428

LD-HE-F-E10-20 High Fresh E10 20 464

LD-HE-A-E0-72 High Aged E0 72 928

LD-HE-A-E0-20 High Aged E0 20 1003

LD-HE-A-E10-72 High Aged E10 72 887

LD-HE-A-E10-20 High Aged E10 20 878

a The repeat test of the normal emitter after all other tests were run is included here but not as part of 

the first two test's averaged data.
70 

TABLE 37. LIGHT DUTY VEHICLE AVERAGE SOLUBLE ORGANIC FRACTION

(No Statistical Analyses Were Performed On These Data)

Test Number Vehicle Lubricant Fuel Temp, F SOF, %

LD-NE-F-E0-72 Normal Emitter Fresh E0 72 47%

LD-NE-F-E0-72-3 a Normal Emitter Fresh E0 72 16%

LD-NE-F-E0-20 Normal Emitter Fresh E0 20 38%

LD-NE-F-E10-72 Normal Emitter Fresh E10 72 10%

LD-NE-F-E10-20 Normal Emitter Fresh E10 20 33%

LD-NE-A-E0-72 Normal Emitter Aged E0 72 19%

LD-NE-A-E0-20 Normal Emitter Aged E0 20 25%

LD-NE-A-E10-72 Normal Emitter Aged E10 72 11%

LD-NE-A-E10-20 Normal Emitter Aged E10 20 26%

LD-HE-F-E0-72 High Emitter Fresh E0 72 96%

LD-HE-F-E0-20 High Emitter Fresh E0 20 95%

LD-HE-F-E10-72 High Emitter Fresh E10 72 96%

LD-HE-F-E10-20 High Emitter Fresh E10 20 96%

LD-HE-A-E0-72 High Emitter Aged E0 72 95%

LD-HE-A-E0-20 High Emitter Aged E0 20 94%

LD-HE-A-E10-72 High Emitter Aged E10 72 92%

LD-HE-A-E10-20 High Emitter Aged E10 20 92%

a The repeat test of the normal emitter after all other tests were run is included here but not as part of 

the first two test's averaged data.

7.5.2.9 Particle Number and Size Distributions

Due to the limited number of repeats taken with the particle number and size data (two 

runs using total particle number (PN) measurement and one run using solid PN measurement), it 

is important to highlight only major differences observed between fresh and aged oil and 

between NE and HE vehicles. Figures 14 and 15 show the exhaust PN concentration for the 

light-duty normal emitter (NE). The data are shown for the fresh and aged oil using E0 and E10 

at 72°F and 20°F. The data are plotted as an average concentration for the cold-start (Bags 1 

and 2) and the hot-start (Bags 3 and 4) portions of the UDC. The exhaust PN concentration 

ranged from about 0.05x106 part./cm3 to 5x106 part./cm3. The combination of cold-start and cold 

ambient temperature operation resulted in the highest PN emissions. The NE vehicle with fresh 

oil emitted a higher number of solid and volatile particles, compared to emissions with the aged 

oil. This was observed at the cold-start and the hot-start portion of the drive cycle. E10 resulted 

in higher particle emissions, compared to E0, particularly at 72°F. At 20°F, there was not a 

consistent trend between E10 and E0. The repeated test with the NE using E0 and fresh oil after 

all other testing at 72°F and 20°F gave much higher PN emissions, compared to the original test 

performed. This was consistent with the trend observed earlier with the PM mass data. This also 

suggests a shift in the PM emissions performance of the NE vehicle. Figures 16 and 17 show the 

percent ratio of solid and volatile PN concentration to total PN concentration. Over 70 percent 

of the number of particles emitted from the NE were solid in nature. This is generally consistent 

with the trend observed with the OC/EC mass and with the SOF results reported earlier on a 

mass basis.
FIGURE 14. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION 

(LIGHT-DUTY, NORMAL EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data) 

FIGURE 15. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION 

(LIGHT-DUTY, NORMAL EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data) 

71 
72 

FIGURE 16. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(LIGHT-DUTY, NORMAL EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 17. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(LIGHT-DUTY, NORMAL EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)
73 

Figures 18 and 19 show the exhaust PN concentration for the light-duty high emitter 

(HE). The exhaust PN concentration ranged from 5x106 part./cm3 to 150 x 106 part./cm3. The 

highest PN concentration observed with the high emitter are a factor of 3000 and 30 higher than 

the lowest and highest concentration observed with the NE, respectively. For the HE, there was 

not a difference in the emissions between the cold-start and the hot-start PN emissions using the 

fresh oil. For the aged oil, the hot-start produced about 50 percent higher PN emissions. Contrary 

to what was observed with the NE, the HE with the aged oil showed much higher particle 

number emissions, compared to that with the fresh oil. The HE number emissions were 

dominated by volatile particles. With the fresh oil, as shown in Figure 20, more than 65 percent 

of the particles were volatile in nature. With the aged oil, as shown in Figure 21, the number of 

volatile particles represents more than 85 percent of total particle number. The volatile fraction 

observed with the HE is consistent with the OC/EC and SOF trends reported earlier on a mass 

basis. However, this trend is opposite to what was observed with the NE, where solid particle 

number and mass dominate total PN and PM composition. 

 Figures 22 through Figure 30 show the size distributions for the light-duty NE using the 

fresh and aged oil with E0 and E10 at 72°F and 20°F. The total and solid particle size 

distributions are shown for the cold-start and hot-start portions of the test. The total and solid 

distributions seem to exhibit a similar bimodal lognormal structure that consists of a nuclei mode 

<20 nm, and an accumulation mode. For the fresh oil, the accumulation mode peaked at about 

50 nm to 60 nm and the nuclei mode peaked at 10 nm. The accumulation mode for the aged oil 

was lower than the fresh oil in concentration and it was at least 20 nm smaller in diameter than 

that for the fresh oil. Since the accumulation mode consists mainly of solid particles, the fresh oil 

seems to contribute to the formation and growth by coagulation of solid particles leading to a 

higher concentration and a larger particle size, compared with the aged oil. Filter measurements 

and OC/EC were inconsistent with these findings. Filter measurements showed higher PM with 

the aged oil, compared to the fresh oil. However, the reader should keep in mind that the size 

distribution data were taken for a limited number of tests, while the PM data were based on an 

interval of 16 different tests spanned over 16 days. The size distribution data were collected at a 

constant dilution ratio from vehicle tailpipe and were reported as averages for the entire coldstart (Phase 1 and Phase 2) and hot-start portions (Phase 3 & Phase 4) of the UDC. These 

differences can contribute to differences in observations, particularly in case of vehicle emissions 

performance shift, as evidenced in Figure 30. The data plotted in Figure 30 represent the same 

conditions as those plotted in Figure 22, but it is a repeat after all the testing performed using E0, 

E10, 72°F, 20°F, with the fresh and aged oil. Figure 30 shows a much higher concentration than 

that observed in Figure 22. However, the size distribution characteristic, particularly the size 

location of the accumulation mode between 50 nm and 60 nm is consistent with that observed 

with the fresh oils, compared to the smaller diameter observed with the aged oils.

Figures 31 through Figure 38 show the size distributions for the light-duty HE using the 

fresh and aged oil with E0 and E10 at 72°F and 20°F. The size distributions are monomodal 

lognormal distributions. The accumulation mode for total particles peaks between 30 nm and 50 

nm and is volatile in nature. This is different from the NE, where the accumulation mode was 

composed mainly of solid particles. For solid particle emissions from the HE, the distribution has 

a nuclei mode at 10 nm similar to that observed with the normal emitter, but with the higher 

concentration. It is speculated that the source of nuclei mode solid particles is the ash inherently
74 

FIGURE 18. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (LIGHTDUTY, HIGH EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 19. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (LIGHTDUTY, HIGH EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)
75 

FIGURE 20. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(LIGHT-DUTY, HIGH EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 21. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES 

(LIGHT-DUTY, HIGH EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)
76 

FIGURE 22. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, NORMAL EMITTER, 

FRESH OIL)

(No Statistical Analyses Were Performed On These Data) 

FIGURE 23. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 72°F, NORMAL EMITTER, 

FRESH OIL)

(No Statistical Analyses Were Performed On These Data)
77 

FIGURE 24. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 20°F, NORMAL EMITTER, 

FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 25. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 20°F, NORMAL EMITTER, 

FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)
78 

FIGURE 26. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, NORMAL EMITTER, 

AGED OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 27. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 72°F, NORMAL EMITTER, 

AGED OIL)

(No Statistical Analyses Were Performed On These Data)
79 

FIGURE 28. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 20°F, NORMAL EMITTER, 

AGED OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 29. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 20°F, NORMAL EMITTER, 

AGED OIL)

(No Statistical Analyses Were Performed On These Data)
80 

FIGURE 30. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, NORMAL EMITTER, 

FRESH OIL, REPEATED TEST AFTER E0, E10 WITH FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 31. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, HIGH EMITTER, 

FRESH OIL)

(No Statistical Analyses Were Performed On These Data)
81 

FIGURE 32. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 72°F, HIGH EMITTER, 

FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 33. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 20°F, HIGH EMITTER, 

FRESH OIL)

(No Statistical Analyses Were Performed On These Data)
82 

FIGURE 34. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 20°F, HIGH EMITTER,

FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 35. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 72°F, HIGH EMITTER, 

AGED OIL)

(No Statistical Analyses Were Performed On These Data)
83 

FIGURE 36. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 72°F, HIGH EMITTER, 

AGED OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 37. NUMBER-WEIGHTED SIZE DISTRIBUTION (E0, 20°F, HIGH EMITTER, 

AGED OIL)

(No Statistical Analyses Were Performed On These Data)
84 

FIGURE 38. NUMBER-WEIGHTED SIZE DISTRIBUTION (E10, 20°F, HIGH EMITTER, 

AGED OIL)

(No Statistical Analyses Were Performed On These Data)

present in fresh lube oil and ash and wear particles present in aged oil, but no chemical analysis 

was performed to quantify the chemical composition of sub-20 nm particles from the high 

emitter. This could be of interest in future work, similar to what was done for the NE as shown in 

the next section. The higher volatile accumulation mode observed with aged oil, compared to 

fresh oil could be related to the lower vapor pressure of the bulk aged oil compared to fresh oil. 

Lower vapor pressure promotes particle nucleation and growth of particles during dilution and 

cooling. Another possibility for the enhanced volatile particle formation with the aged oil, 

compared to fresh oil, is the higher presence of solid wear particles that may act as 

condensation/nucleation site during dilution and cooling of the hot exhaust. More systematic 

future research efforts are needed to better understand these phenomena.

7.5.2.10 MOUDI Test Results

It is hypothesized that the nuclei mode solid particles consist of ash particles derived 

from the lube oil. The ash particles form later in combustion during the expansion stroke creating 

nuclei mode particles that do not have enough time to coagulate with the accumulation mode. 

To prove this hypothesis, we used a MOUDI and nano-MOUDI impactors for size-specific mass 

collection and elemental analysis. The idea was to show that particles in the sub-30 nm size 

range are dominated by lube-related ash particles including P, S, Ca, and Zn. 

Figure 39 shows the PM mass cumulative fraction as a function of particle diameter. 

More than 80 percent of the particle mass is in the ultrafine range below 0.1 μm in aerodynamic 
85 

diameter and more than 50 percent is in the nanoparticle size range below 0.05 μm in diameter. 

Figure 40 shows the size-specific elemental mass as a percent of size-specific total PM mass. 

The limited MOUDI elemental analysis performed in this work showed that the percent of 

elemental mass relative to total PM mass is very low (<0.5%) and similar across the size range 

between 0.01 μm and 0.3 μm. Thus, the measured elements do not dominate the PM mass even 

in the sub-30 nm size range, as suspected, where solid nuclei are present on a number basis, as 

shown in Figures 22 and 23. However, if one looks at particles larger than 0.3 μm in diameter, 

the percent elemental mass (particularly Ca) increased to a level reaching 23 percent. This high 

percentage of elements at the upper stages can possibly be due to the diffusion of small metallic 

ash particles to the upper stages of the MOUDI. Due to the high solid fraction of particles

observed with the NE, as shown in Figures 16 and 17, it is likely that the sub-30 nm solid 

particles are dominated by soot or some other metallic elements that are different from Ca and 

Zn. Future efforts should focus on using the MOUDI for both elemental analysis and particle 

morphology. Particle morphology coupled with energy dispersion X-ray spectroscopy should 

help determine the physical characteristics and elemental composition of small particles 

depositing on the upper stages of the MOUDI, if any. Figure 41 shows P, S, Ca, and Zn as a 

percent of total PM. S, P, Ca, and Zn, represent 0.5%, 0.2%, 0.15%, and 0.15% of total PM of 

1.44 mg/mi. The sum of measured elements represents one percent of the total PM emissions or 

14.4 μg/mi. 

FIGURE 39. SIZE SPECIFIC CUMULATIVE MASS FRACTION

(No Statistical Analyses Were Performed On These Data)
86 

FIGURE 40. SIZE-SPECIFIC ELEMENTS AS A PERCENT OF TOTAL PM 

(No Statistical Analyses Were Performed On These Data)

FIGURE 41. ELEMENTAL COMPOSITION AS A PERCENT OF TOTAL PM MASS

(No Statistical Analyses Were Performed On These Data)
87 

7.6 PM Apportionment

We compared the exhaust emission rates for the four alternative tracers of lubricating oil, 

elements (Ca, P, Zn and Mo), hopanes and steranes, unresolved complex mixture (UCM) of ~C20

to C35 alkanes, and deuterated hexatriacontane (C36D74), with corresponding concentrations of 

the oil tracers in lubricating oils. Separate estimates of the lubricating oil consumption (LOC) 

rates were derived from ratios of the mass emission rates of the four oil tracers to their mass 

fractions in the oils. These LOC rate estimates were then compared to the measured LOC (HE 

vehicle only) and to the NE and HE vehicle exhaust emissions of PM, TC and OC. We estimated 

the fuel and oil contributions to the exhaust PM, TC and OC by multiple regressions using high 

molecular weight PAH as the fuel tracer and each of the alternative oil tracers.

7.6.1 Composition of Lubricating Oils and Fuels

Table 38 summarizes the chemical composition of the fresh and aged lubricating oils and 

gasolines with zero or 10% ethanol by volume, as tested during the CLOSE Project. Oil samples 

include the fresh and aged oils as received, and samples taken after the cold (20°F) tests with 

fresh and aged oils on E0 and then E10 for both the normal and high emitter. For example, the 

normal emitter was operated over multiple emission tests with fresh oil and a sample was taken 

from the crankcase drain oil after the cold tests on E0 fuels, and then the normal emitter was 

operated over multiple emissions tests with fresh oil on E10 fuels and a sample was taken from 

the crankcase drain oil after the cold tests. Thus five oil samples were taken from the normalemitter (two fuel types and two oils, plus one repeat test on E0 with fresh oil), and four oil 

samples were taken from the high emitter. The summary includes the concentrations (μg/g) of 

oil additive elements (Ca, P, Zn and Mo), sum of hopanes and steranes, identified C12-C19

alkanes, identified C20-C35 alkanes (i.e., individually resolved peaks above the UCM), UCM of 

~C20-C35 alkanes, measured and expected C36D74, sum of all quantified PAH from naphthalene to 

coronene, and the three high molecular weight PAH, benzo(ghi)perylene, indeno[123-cd]pyrene 

and coronene. Elements were measured by both XRF and ICP-MS for oils samples from the 

normal emitter vehicle only.

The mass fraction of UCM alkanes was about 75 percent for the fresh oil (as received) 

and about 45 percent for the aged oil (as received). The lower fractions of UCM alkanes in the 

aged oil can result from combustion of the oil in the engine, entrainment of the more volatile 

alkanes with the exhaust, and oxidation of the oil. The insoluble oxidation products consist of 

polar compounds that are not extracted with the UCM alkanes during sample preparation and 

were not measured in this study. After completing each series of tests in the NE vehicle, the 

fractions of UCM alkanes were lower for the fresh oil (54 to 66 percent) and, considering the 

uncertainty of the UCM estimates, were comparable to pre-test concentrations for the aged oils 

(53 and 55 percent). In contrast, the post-test UCM mass fractions of the oils from the HE 

vehicle were substantially lower (near 20 percent) for both fresh and aged oils, indicating that the 

lubricating oils had degraded rapidly in this HE vehicle. 
88 

TABLE 38. CONCENTRATIONS OF OIL ADDITIVE ELEMENTS, HOPANES, STERANES, ALKANES AND POLYCYCLIC 

AROMATIC HYDROCARBONS (μG/G) IN FRESH AND AGED LUBRICATING OILS, AND GASOLINES WITH ZERO OR 

10% ETHANOL BY VOLUME

(No Statistical Analyses Were Performed On These Data)

1 Code: NE - normal emitter, HE - high emitter, F - fresh oil, A - aged oil, E0 and E10 - gasoline with 0 and 10% ethanol by volume.

2 All oils were analyzed for elements at DRI by XRF and subset of oil samples analyzed at EAI by ICP-MS is shown in parentheses.

3 Lubricating oil for the light-duty vehicles were blended with 7.35 g of C36D74 per quart of oil.

4 Sums include PAH from naphthalene to coronene. 5 High molecular weight PAH include, benzo(ghi)perylene, indeno[123-cd]pyrene and coronene. 

Lubricating Oil Additive Metals 2 Sum of Alkanes Sum of PAH

Lubricating Oils and 

Gasolines 1

Ca P Zn Mo

Hopanes 

Steranes

Identified 

C12-C19

Identified 

C20-C35

UCM 

C20-C35

Measured 

C36D74

Expected3 

C36D74

all 4 

PAH

High MW 

PAH 5

Oils

 Fresh as received 2240 291 860 58 85 110 4,870 740,000 0 0 100 1.4

 Aged as received 2529 491 1070 89 89 171 2,870 450,000 0 0 1,100 10.0

 NE-F-E0-72,20 2353 (1941) 318 (722) 1031 (863) 76 (72) 105 75 5,240 540,000 520 9,370 1,490 10.3

 NE-F-E10-72,20 2270 (1948) 305 (722) 967 (917) 70 (71) 131 273 8,150 660,000 2,040 9,700 1,880 2.7

 NE-A-E0-72,20 2497 (2089) 276 (654) 1025 (877) 84 (79) 104 76 6,290 530,000 700 9,030 1,680 18.6

 NE-A-E10-72,20 2412 (2050) 211 (631) 989 (839) 81 (82) 95 116 8,730 550,000 710 9,100 1,950 14.3

 HE-F-E0-72,20 2298 161 1106 86 126 89 6,340 210,000 570 9,020 2,700 10.6

 HE-F-E10-72,20 2279 0 1050 81 141 99 6,700 220,000 390 9,040 2,300 3.5

 HE-A-E0-72,20 2392 0 1064 91 107 95 6,000 220,000 870 9,050 2,380 21.3

 HE-A-E10-72,20 2328 0 1058 84 114 94 5,830 210,000 730 8,890 780 3.4

 NE-F-E0 repeat 2318 330 962 69 107 101 8,000 630,000 2,450 9,910 1,720 6.1

Gasolines

 Regular (E0) NA NA NA NA 1.0 149 55 1,525 NA NA 4,780 0.12

 E10 NA NA NA NA 1.5 894 47 1,307 NA NA 10,990 0.12

 Original Cold CO NA NA NA NA 0.7 74 39 1,342 NA NA 2,520 0.00

 Cold E10 NA NA NA NA 0.9 83 39 1,516 NA NA 2,610 0.09

 New Cold CO (E0) NA NA NA NA 0.7 145 29 493 NA NA 1,810 0.00
89 

Unlike UCM alkanes, the concentrations of hopanes and steranes in both fresh and aged 

oil increased after testing in both the NE and HE vehicles. The increases in concentrations were 

generally higher for the HE vehicle. The concentrations of the additive elements in the fresh oil 

increased after testing in both the NE and HE Vehicles. Vaporization and/or combustion of the 

lighter alkanes in the oils could account for the generally higher concentrations of hopanes and 

steranes in the oil samples after testing. This could also account for the higher post-test 

concentrations of additive element. The lower post-test concentrations of additive elements in 

the HE vehicle indicate deposition or other loss of these additive metals. Phosphorous 

concentrations were zero for most oil samples (both fresh and aged oil) from the high emitter 

vehicle. However, this may have been due to self-absorption of the phosphorus X-rays by 

elemental carbon present in the oil samples. All oil samples from the high emitter vehicle were 

much darker than the oils taken from the normal-emitting vehicle. This is especially remarkable 

given that the HE oils were subjected to far fewer repeat UDC cycles. While concentrations of 

Ca, Zn and Mo in the oils measured by XRF and ICP-MS were generally within 20%, the XRF 

values for P were consistently lower (~0.4) than measured by ICP-MS. Values for P were 

excluded from the LOC estimates and PM apportionments of fuel combustion and lubricating 

oils.

The lubricating oils used in the CLOSE light-duty vehicle tests were blended with 7.35 g 

of C36D74 per quart of oil, which equates to an expected concentration in the oil of about 

9,000 μg of C36D74 per gram of oil. The measured concentrations were substantially lower (400 

to 2,450 ppm) than expected and highly variable. Especially puzzling was that the repeat samples 

had C36D74 concentrations of 523 and 2,042 ppm. Assuming that no errors were made in the 

addition of the tracer to the oil samples, these results suggest that C36D74 was consumed at 

varying rates during the tests or not uniformly mixed in the oil samples when drawn for analysis 

several months following the emission testing sequence. In contrast, the exhaust emissions of 

C36D74, shown in Table 39, were more similar among the various tests for the HE vehicle, 

indicating that the oils were more uniformly mixed in the crankcase during testing. While the 

LOC estimates can be affected by variations in uniformity of the oil samples, the multiple 

regression results are based on emissions data and should not be affected.
90 

TABLE 39. PARTICLE-PHASE EXHAUST EMISSION RATES (TUNNEL BLANK SUBTRACTED) OF OIL ADDITIVE AND 

ENGINE WEAR ELEMENTS, HOPANES AND STERANES (H&S), IDENTIFIED AND UNRESOLVED COMPLEX 

MIXTURE (UCM) OF ALKANES AND CYCLOALKANES, DEUTERATED HEXATRIACONTANE, PAH AND SUM OF 

THREE HIGH-MW PAH COLLECTED ON TEFLON-IMPREGNATED GLASS FIBER (TIGF) FILTERS

(No Statistical Analyses Were Performed On These Data)

1 Code: NE - normal emitter, HE - high emitter, F - fresh oil, A - aged oil, E0 and E10 - gasoline with 0 and 10% ethanol by volume. 2 Elements were analyzed at DRI by XRF and ICPMS (shown in parentheses). 

3 Sum of the engine wear metals (Cu, Al, and Fe by ICPMS). 4 Sums include PAH from naphthalene to coronene.

5 High molecular weight PAH include, benzo(ghi)perylene, indeno[123-cd]pyrene and coronene

Lubricating Oil Additive Metals (μg/mi) 2 Alkanes (μg/mi) PAH (μg/mi)

Vehicle Test1 

Ca 

XRF (ICP)

P 

XRF

Zn 

XRF (ICP)

Mo 

XRF (ICP)

Wear 

Metals3 

ug/mi

H&S 

μg/mi

Identified 

C12-C19

Identified 

C20-C35

UCM 

C20-C35 C36D74

all 4 

PAH

High MW 

PAH 5

NE-F-E0-72 18 (16) 6 6 (5) 0.5 (0.3) 5 0.0 2 5 6 0.0 0.4 0.0

NE-F-E0-20 89 (80) 33 37 (29) 2.3 (1.5) 24 0.3 12 2115 272 0.2 4.8 0.9

NE-F-E10-72 22 (19) 8 8 (6) 0.6 (0.4) 5 0.1 5 0 0 0.0 1.3 0.0

NE-F-E10-20 126 (110) 48 51 (39) 2.8 (1.8) 26 0.2 9 1036 192 0.0 4.7 0.7

NE-A-E0-72 31 (27) 9 10 (7) 0.9 (0.6) 4 0.1 0 0 0 0.0 1.0 0.0

NE-A-E0-20 77 (69) 25 28 (21) 2.2 (1.4) 16 0.3 42 1546 203 0.0 7.5 1.5

NE-A-E10-72 31 (27) 10 10 (7) 1.1 (0.6) 2 0.1 1 0 0 0.0 2.1 0.1

NE-A-E10-20 89 (79) 30 32 (24) 2.7 (1.5) 17 0.3 220 806 26 0.1 8.1 2.0

HE-F-E0-72 1273 (1368) 226 437 (376) 41 (36) 54 75.5 306 1723 40300 214 146 1.0

HE-F-E0-20 1164 (1418) 202 379 (365) 38 (35) 39 59.0 336 3456 38900 212 152 1.8

HE-F-E10-72 1214 (1513) 171 363 (358) 29 (27) 23 49.5 542 4977 41900 391 104 0.3

HE-F-E10-20 1181 (1392) 177 368 (355) 30 (28) 26 49.0 594 3177 40300 468 94 0.1

HE-A-E0-72 1182 (1427) 261 335 (324) 42 (39) 27 52.6 467 1603 34900 399 86 0.2

HE-A-E0-20 1294 (1468) 305 412 (361) 49 (41) 32 44.8 641 925 41600 563 137 0.6

HE-A-E10-72 1252 (1406) 318 442 (392) 49 (41) 71 35.5 432 822 32200 394 98 0.4

HE-A-E10-20 1126 (1271) 288 385 (352) 43 (37) 38 35.4 437 743 28900 410 74 0.6
91 

Each of the gasoline samples contained trace amounts of hopanes and steranes that could 

confound the aforementioned apportionment method. The potential contributions from the fuel to 

exhaust emissions of hopanes and steranes ranged from 149 to 168 μg/mi, based on fuel 

consumed multiplied by mass fractions of hopanes and steranes in the fuel. The potential 

contributions from the oils, estimated from the LOC rates (using elemental tracers) times the 

mass fractions of hopanes and steranes in oil, are 1.1, 4.4 and 59.1 μg/mi for the NE vehicle at 

72°F, NE vehicle at 20°F and HE vehicle at both temperatures, respectively. These estimates are 

based on an unlikely assumption that hopanes and steranes from both the fuel and oil are entirely 

conserved without loss in the engine or exhaust system. Most of the hopanes and steranes in the 

fuel are consumed in the engine along with the fuel. Hopanes and steranes would be emitted with 

the unburned fuel with greater amounts for fuel-rich high emitters.

Although the actual loss rates of hopanes and steranes from the fuels and oils are 

unknown, the CLOSE test data provide indications of their relative contributions. Compared to 

the potential contributions of hopanes and steranes from unburned fuels and oil, the average 

exhaust emission rates were 0.1, 1.0 and 53 μg/mi for the NE vehicle at 72°F, NE vehicle at 20°F 

and HE vehicle at both temperatures, respectively. These exhaust emission rates are similar to 

the potential contributions of hopanes and steranes from the oils and Figure 42 shows that the 

composition of individual hopanes and steranes in the oils and HE vehicle exhaust are nearly 

identical. Furthermore, the ratios of the elemental tracers for oil, Ca, Zn and Mo, to hopanes and 

steranes are the same in the oil and HE exhaust. These observations indicate that lubricating oils 

are likely the main contributor to exhaust emissions of hopanes and steranes for the HE vehicle. 

Results for the NE vehicle are less clear due to greater analytical uncertainty and potentially 

greater relative contribution of unrelated emissions from surface deposits in the engine and 

exhaust system components. For example, the ratios of the elemental tracer of oil to hopanes and 

steranes are about 15-20 times greater in the exhaust compared to the corresponding ratios in the 

lubrication oils. While comparisons of the potential contribution of the fuel (149 to 168 μg/mi) to 

exhaust emissions of hopanes and steranes for the NE vehicle (0.1 to 1.0 μg/mi) suggest that 

most hopanes and steranes are burned in the engine with the fuel, the residual amounts in 

unburned fuel could be significant for NE vehicles with low LOC rates. The greater analytical 

uncertainties associated with measurements of low emission rates, as illustrated by the greater 

variability in composition of individual hopanes and steranes in the NE vehicle exhaust (Figure 

42), also contribute to greater uncertainty in quantifying the contributions of fuel combustion and 

lubricating oil to exhaust PM for NE vehicles. 
92 

FIGURE 42. COMPOSITION OF INDIVIDUAL HOPANES AND STERANES FROM FUEL 

AND OIL RELATIVE TO MEASURED EXHAUST EMISSIONS RATES

Table 38 shows that fresh lubricating oils contain relatively low amounts of PAH 

compared to aged oils. Aged oils accumulate PAH by absorbing unburned fuel and combustion 

products contained in the blow-by gases. Most of the absorbed PAH from unburned gasoline are 

low-molecular weight PAH (e.g., naphthalene and methylnaphthalenes). Incomplete combustion 

of the fuel produces a variety of high molecular weight PAH (e.g., benzo(ghi)perylene, 

indeno[123-cd]pyrene and coronene) that are potential tracers of PM from fuel combustion. 

These PAH are valid tracers of fuel combustion if the contributions of the oil to exhaust 

0%

20%

40%

60%

80%

100%

E0 E10 Cold 

E0

Cold

E10

E0 E10 Cold 

E0

Cold

E10

E0 E10 Cold 

E0

Cold

E10

E0 E10 Cold 

E0

Cold

E10

72 20 72 20 72 20 20 72 20

Fresh Aged Fresh Aged

NE Exhaust HE Exhaust

ster53

ster52

ster51

ster50

ster49

ster48_41

ster47

ster46

ster45_40

ster44

ster43

ster42

hop27

hop26

hop25

hop24

hop23

hop22

hop21

hop20

hop19

hop17

hop15

0%

20%

40%

60%

80%

100%

E0 E10 Cold 

E0

Cold

E10

E0 E0 E10 E0 E0 E10 E0 E10 E0 E10 E0 E10

Fuel Fresh Aged Fresh Aged Fresh Age

Rec'd Oil NE Oil HE Oil

ster53

ster52

ster51

ster50

ster49

ster48_41

ster47

ster46

ster45_40

ster44

ster43

ster42

hop27

hop26

hop25

hop24

hop23

hop22

hop21

hop20

hop19

hop17

hop15
93 

emissions of the PAH are small. As with the fuel, combustion of the lubricant could also result in 

formation of high-molecular weight PAH resulting in underestimation of the potential 

contribution of lubricating oil by this method. We also estimated the potential lubricating oil 

contributions to the mass emission rates of benzo(ghi)perylene, indeno(1,2,3-cd)pyrene, and 

coronene in the exhaust PM by multiplying the mass fractions of these PAH in lubricating oils by 

the estimated LOC rates shown in Table 40. The oil contributions to combustion-derived PAH 

were small for the normal emitter due primarily to low LOC rates. The oil contributions alone 

equaled or exceeded the measured exhaust emission rates of high-molecular weight PAH for the 

high emitter resulting in overestimations of the fuel combustion contributions to PM emissions. 

Despite this overestimation, most of the PM emissions for the high emitter were apportioned to 

lubricating oil.

TABLE 40. LUBRICATING OIL CONSUMPTION RATES BASED UPON RATIOS OF THE 

EMISSION RATES OF ELEMENTAL TRACERS, UCM, SUM OF HOPANES AND

STERANES, AND DEUTERATED HEXATRIACONTANE TO THEIR 

CONCENTRATIONS IN THE CORRESPONDING LUBRICATING OIL

(No Statistical Analyses Were Performed On These Data)

1 Code: NE - normal emitter, HE - high emitter, F - fresh oil, A - aged oil, E0 and E10 - gasoline with 0 

and 10% ethanol by volume. 

2 LOC estimates based on sum of Ca, Zn and Mo.

LOC (mg/mi) based on following tracers

Vehicle Test1 Metals2

Ca Zn Mo H&S C36D74 UCM

NE-F-72-E0 7.2 7.6 6.3 6.0 0.8 0.1 2.3

NE-F-72-E10 9.3 9.6 8.4 8.9 0.9 0.0 0.2

NE-F-20-E0 36.9 37.8 35.4 30.6 9.8 0.3 3.2

NE-F-20-E10 54.3 55.5 52.4 40.3 4.6 0.1 0.5

NE-A-72-E0 11.6 12.3 9.8 10.9 0.7 0.0 0.0

NE-A-72-E10 12.1 12.7 10.5 13.4 1.0 0.0 0.2

NE-A-20-E0 29.9 31.0 27.6 26.7 14.1 0.0 0.5

NE-A-20-E10 35.5 36.8 32.7 32.9 8.3 0.1 0.5

HE-F-72-E0 502 554 395 474 620 569 201

HE-F-72-E10 471 533 345 359 367 466 196

HE-F-20-E0 453 507 343 448 488 566 191

HE-F-20-E10 463 518 350 372 366 551 188

HE-A-72-E0 440 494 315 468 512 567 163

HE-A-72-E10 502 538 417 583 333 164 156

HE-A-20-E0 495 541 387 536 438 791 195

HE-A-20-E10 448 484 364 510 329 171 139
94 

7.6.2 Components of Exhaust PM

Table 39 shows sums of the elemental tracers of lubricating oil and engine wear, and 

sums of several groups of particle-phase organic compounds (POC) collected on the TIGF filters. 

Data for the vehicle tests are shown in the order in which they were conducted and are averages 

of the two replicates for each series of tests. Oil additive elements are shown individually for Ca, 

P, Zn and Mo measured by XRF and by ICP-MS. The two measurements were in good 

agreement for the high emitter vehicle with average XRF/ICP-MS ratios and standard deviations 

of 0.86 ± 0.04, 1.08 ± 0.06 and 1.13 ± 0.04, for Ca, Zn and Mo, respectively. These results 

indicate that PM deposits on the filter samples were uniform. However, values for XRF were 

higher than ICP-MS by factors of 1.13±0.02, 1.32±0.04 and 1.58±0.14, for Ca, Zn and Mo, 

respectively for samples from the normal emitter vehicle. Engine wear metals in Table 39 are

sums of Al, Cu, and Fe measured by ICP-MS. The groups of particle-phase organic compounds 

include: identified C12-C19 alkanes, identified C20-C35 alkanes (i.e., individual peaks appearing 

above the UCM “peak”), UCM of C20-C35 alkanes, C36D74, sum of all quantified PAH from 

naphthalene to coronene, and the three high molecular weight PAH, benzo(ghi)perylene, 

indeno[123-cd]pyrene and coronene. 

As expected, the amounts of various components of exhaust PM for the NE and HE 

vehicles are consistent with higher contributions of lubricating oil for the HE. The higher PM 

emission rates for the HE vehicle are accompanied by organic carbon/total carbon (OC/TC) 

ratios greater than 90%, and substantially greater emissions of oil additive elements, hopanes and 

steranes, UCM and C36D74 than for the NE vehicle. Based on estimates OC from UCM (by 

dividing UCM by 1.17 mass ratio of C27H56/C27), UCM accounted for about 50% of the 

measured OC for all tests of the HE vehicle and 36% and 3% for the NE vehicle tested at 20°F 

and 72°F, respectively. NE UCM emission rates were very low with correspondingly higher 

uncertainties. Elemental carbon is the dominant component of total particle-phase carbon 

emissions for the NE, suggesting the relatively greater contribution of fuel combustion to PM 

emissions from the low-emitting normal emitter. The emission rates of high molecular weight 

PAHs were comparable for the NE and HE vehicles resulting in similar contributions of fuel 

combustion PM from the MLR analysis, which is consistent with similar EC emission rates.

The blank-subtracted emission rates of volatile phase of semi-volatile organic compounds 

collected on the backup XAD-4 cartridges are shown in Table 41 for the NE and HE test 

vehicles. For a few of the NE tests, subtraction of the tunnel blanks for C12-C19 alkanes resulted 

in negative emission rates. PAH exhibit a wide range of volatility with naphthalene existing 

almost entirely in the gas phase, while five-ring and higher ring PAH are adsorbed 

predominantly on particles. The intermediate three- and four-ring PAH (semi-volatile PAH) are 

distributed between the two phases. The emissions of semi-volatile PAH for the NE vehicle 

exceeded particle-phase PAH by approximately two orders of magnitude and particle-phase OC 

by about a factor of two. The organic compound tracers of lubricating oil (hopanes and steranes, 

UCM and C36D74) and fuel combustion tracers (high molecular weight PAH) were all 

predominantly in the particle phase. 
95 

TABLE 41. VOLATILE PHASE OF SEMI-VOLATILE COMPOUNDS EXHAUST EMISSION 

RATES (TUNNEL BLANK SUBTRACTED) OF IDENTIFIED HOPANES AND STERANES 

(H&S), IDENTIFIED AND UNRESOLVED COMPLEX MIXTURE (UCM) OF ALKANES 

AND CYCLOALKANES, DEUTERATED HEXATRIACONTANE, PAH AND SUM OF

3 HIGH-MW PAH1 COLLECTED ON BACKUP XAD-4 CARTRIDGES

(No Statistical Analyses Were Performed On These Data)

1 Code: NE - normal emitter, HE - high emitter, F - fresh oil, A - aged oil, E0 and E10 - gasoline with 0 

and 10% ethanol by volume.

2 Sums include PAH from naphthalene to coronene. 3 High molecular weight PAH include, benzo(ghi)perylene, indeno[123-cd]pyrene and coronene. 

Alkanes (μg/mi) PAH (μg/mi)

Vehicle Test1 

H&S 

μg/mi

Identified 

C12-C19

Identified 

C20-C35

UCM 

C20-C35 C36D74

all 2 

PAH

High MW 

PAH 3

NE-F-E0-72 0.0 1 0 1228 0.0 97 0.00

NE-F-E0-20 0.7 14 0 1449 0.0 861 0.00

NE-F-E10-72 0.0 13 0 123 0.0 242 0.00

NE-F-E10-20 0.5 29 194 151 0.0 494 0.00

NE-A-E0-72 0.0 2 0 0 0.0 92 0.00

NE-A-E0-20 1.2 -60 86 70 0.0 903 0.00

NE-A-E10-72 0.0 20 0 126 0.0 283 0.00

NE-A-E10-20 0.5 -84 186 224 0.0 680 0.00

HE-F-E0-72 2.3 139 79 1531 6.6 2116 0.00

HE-F-E0-20 2.3 194 229 856 6.8 2240 0.00

HE-F-E10-72 2.3 498 333 1167 16.2 4009 0.00

HE-F-E10-20 2.7 264 198 961 14.2 2558 0.00

HE-A-E0-72 2.0 575 265 666 11.8 3163 0.00

HE-A-E0-20 1.9 218 259 1017 10.5 2378 0.00

HE-A-E10-72 2.5 451 324 960 7.7 3688 0.00

HE-A-E10-20 2.1 177 429 613 9.1 1546 0.00
96 

7.6.3 Estimates of LOC from Chemical Components of Exhaust PM and Lubricating Oil

Lubricating oil consumption rates were estimated from ratios of the exhaust emission 

rates of oil tracers to their mass fractions in the corresponding lubricating oils assuming the 

following linear relationship, Et (μg/mi) = mCt (μg/g), where Et is exhaust emission rate of oil 

tracer t in μg/mile and Ct is the concentration of oil tracer t in μg/g. The slopes, although related 

to the lubricating oil consumption (LOC) rate, underestimate the true LOC rate due to losses of 

oil by combustion oxidation of organic compounds; evaporation of volatile components of the 

oil; deposition on internal surfaces of the combustion chamber, exhaust system, the CVS and 

sample transfer lines. The use of elemental tracers yields larger LOC estimates than organic 

tracers because some fraction of the organic components of oil are consumed during combustion, 

while the elements are largely conserved and are emitted in the exhaust as ash.

The LOC rate estimates shown in Table 40 are based upon ratios of the emission rates of 

the four alternative oil tracers: elemental tracers, UCM, sum of hopanes and steranes, and 

deuterated hexatriacontane to their concentrations in the corresponding lubricating oil. The LOC 

rates estimated for the normal emitter were generally negligible using C36D74 (0 to 0.3 mg/mi) or 

UCM (0 to 3.2 mg/mi) as the oil tracers, which are reflected in the low OC emission rates (0 to 

0.5 mg/mi). The range of LOC estimates were higher using hopanes and steranes (1 to 14 mg/mi) 

and highest using elements (7 to 55 mg/mi) as the tracer. The higher LOC estimates with 

elements are consistent with greater loss of the organic tracers.

LOC estimates for the HE vehicle ranged from 440 to 502 mg/mi and 329 to 620 mg/mi 

using metals (sum of Ca, Zn and Mo) and hopanes and steranes, respectively. LOC rate estimates 

using the individual metals are also shown in Table 40 for comparison. A similar range of LOC 

rate estimates was obtained using C36D74 for the first five of eight series of tests (466 to 569 

mg/mi) and more variable for the final three series of tests (164 to 791 mg/mi). UCM as the 

tracer yielded consistently lower LOC estimates (139 to 201 mg/mi), which may be due to partial 

combustion of the UCM alkanes. However all LOC rates for the HE vehicle exceed the OC 

emission rates of 45-79 mg/mi (Table 35). All of the LOC estimates are much lower than the 

measured LOC for the high emitter of 2,560 mg/mi indicating substantial loss of the oil by 

deposition on surfaces of combustion chamber, exhaust system, transfer lines, and CVS or 

combustion in the engine and catalytic converter. 

7.6.4 Estimation of Fuel-Combustion and Oil Contributions by Multiple Regression

We estimated the fuel and oil contributions to the exhaust emission rates of PM, TC and 

OC (mg/mi) by the multiple regressions equation, TC = m1x1 + m2x2 + b (fitted through zero) 

using tracers for lubricating oil and gasoline combustion as was recently done by Kleeman.

22 

Fuel combustion contribution is m1x1 where x1 is the emission rate (mg/mi) of the sum of high 

molecular weight PAH, benzo(ghi)perylene, indeno[123-cd]pyrene and coronene. The oil 

contribution is m2x2 where x2 is the emission rate (mg/mi) of the alternative oil tracer (additive 

elements, UCM, hopanes + steranes or C36D74). The coefficients, m1 and m2, are ratios of the 

mass emissions of PM, TC or OC per mass of fuel and oil tracers, respectively. The regressions 

were performed using PAH as the fuel tracer and each of the alternative oil tracers.
97 

The summary of the multiple regressions results for TC in Table 42 shows good 

correlations for all oil tracers with r2 values ranging from 0.88 to 0.99. Considering the margin of 

error, all of the TC emissions of the high emitter vehicle were apportioned to lubrication oil 

using metals, hopanes and steranes, and UCM as the oil tracer. Oil was the main source of TC 

emission with the C36D74 tracer, but with greater variability. Over 80 percent of the TC emissions 

were apportioned for the normal emitter vehicle to fuel combustion using UCM and C36D74 as oil 

tracers. The range in apportionments to fuel combustion from 20% to about 90% using hopanes 

and steranes is partially due to the higher uncertainties associated with the very low emission 

rates of this oil tracer from the normal emitter vehicle. Use of metals as the oil tracers resulted in 

apportionments of TC to mostly oil (>70%) due to the aforementioned concentration of metal in 

the oil with use. In addition, deposits in the engine and exhaust system may have contributed 

additional metals.

7.6.5 Conclusions

While the results of the CLOSE Project do not represent the entire in-use vehicle 

population, they demonstrate the potential use of lubricant tracer species to apportion the 

contributions of lubricating oils to PM emissions from light-duty gasoline-powered motor 

vehicles. Consistent with estimated high LOC rates, multiple linear regression results showed 

that nearly all of the exhaust PM from the CLOSE LD high emitter was associated with 

lubrication oil as expected. While the presence of elemental tracers and UCM alkanes indicates 

some contributions of the oil to exhaust PM for the CLOSE normal emitter, the relative fuel and 

oil contributions are uncertain due to low emission levels. The emissions of semi-volatile PAH 

for the NE vehicle exceeded particle-phase PAH by approximately two orders of magnitude and 

particle-phase OC by about a factor of two indicating that the NE gasoline-powered vehicles may 

contribute more SOA precursor than direct PM.

Noteworthy is the observation that the UCM fraction of the aged oil was substantially 

lower for both fresh and aged oils from tests with the HE vehicle (Table 31). These decreases in 

the weight fractions of UCM alkanes in the oils may be due to differential loss through volatility, 

conversion from oxidation or some other mechanism. The products of oil oxidization were not 

determined in this study. This decrease was not taken into account in the MLR analysis since 

end-of-test or lowest UCM content of the oil was used while the exhaust samples were collected 

during earlier tests with lubricating oil with varying, but likely higher UCM content. This could 

potentially bias the regression analysis and overestimate the lubricant allocation. The similarity 

in MLR results for UCM and hopanes and steranes as alternative oil tracers may very well be an 

artifact of the fact that only two vehicles representing two extremes are included. Additional 

work is needed to determine the fate of the missing UCM.
98 

TABLE 42. LUBRICATING OIL AND FUEL COMBUSTION CONTRIBUTIONS TO TOTAL CARBON EMISSIONS BASED 

UPON MULTIPLE LINEAR REGRESSION USING ELEMENTAL TRACERS, UCM, SUM OF HOPANES AND STERANES, 

AND DEUTERATED HEXATRIACONTANE AS ALTERNATIVE TRACERS FOR OIL CONTRIBUTIONS AND HIGHMOLECULAR WEIGHT PAH AS THE FUEL COMBUSTION TRACER

(No Statistical Analyses Were Performed On These Data)

1 Code: NE - normal emitter, HE - high emitter, F - fresh oil, A - aged oil, E0 and E10 - gasoline with 0 and 10% ethanol by volume.2

Contributions were determined by multiple linear regression, TC = m1x1 + m2x2 +b (fitted through zero). Fuel combustion contribution is m1x1

where x1 is the sum of high molecular weight PAH include, benzo(ghi)perylene, indeno[123-cd]pyrene and coronene. Oil contribution is m2x2

where x2 is the oil tracer identified in the column headings, additive elements, UCM, hopanes + steranes, or deuterated hexatriacontane.

Metals UCM C20-C35 Hopanes + Steranes C36D74

R2

 = 0.97 R2

 = 0.99 R2 = 0.99 R2 = 0.88

Vehicle Test1

TC 

mg/mi

Fuel 

Combustion

Lube 

Oil

Fuel 

Combustion

Lube 

Oil

Fuel 

Combustion

Lube 

Oil

Fuel 

Combustion

Lube 

Oil

LD-NE-F-E0-72 0.3 0.0 ± 0.0 1.0 ± 0.1 0.0 ± 0.0 0.0 ± 0.0 0.0 ± 0.0 0.0 ± 0.0 0.1 ± 0.1 0.0 ± 0.0

LD-NE-F-E10-72 1.2 0.0 ± 0.1 1.3 ± 0.1 0.1 ± 0.0 0.0 ± 0.0 0.0 ± 0.1 0.1 ± 0.0 0.3 ± 0.1 0.0 ± 0.0

LD-NE-F-E0-20 2.7 1.0 ± 2.9 5.3 ± 0.3 2.6 ± 1.3 0.5 ± 0.0 1.2 ± 2.7 0.4 ± 0.0 9.6 ± 4.1 0.0 ± 0.0

LD-NE-F-E10-20 4.2 0.8 ± 2.2 7.5 ± 0.5 2.0 ± 1.0 0.3 ± 0.0 0.9 ± 2.1 0.2 ± 0.0 7.5 ± 3.2 0.0 ± 0.0

LD-NE-A-E0-72 0.7 0.0 ± 0.0 1.7 ± 0.1 0.0 ± 0.0 0.0 ± 0.0 0.0 ± 0.0 0.1 ± 0.0 0.2 ± 0.1 0.0 ± 0.0

LD-NE-A-E10-72 1.5 0.1 ± 0.2 1.7 ± 0.1 0.2 ± 0.1 0.0 ± 0.0 0.1 ± 0.2 0.1 ± 0.0 0.6 ± 0.2 0.0 ± 0.0

LD-NE-A-E0-20 3.5 1.6 ± 4.7 4.4 ± 0.3 4.3 ± 2.2 0.4 ± 0.0 1.9 ± 4.5 0.4 ± 0.0 15.8 ± 6.7 0.0 ± 0.0

LD-NE-A-E10-20 3.8 2.2 ± 6.5 5.0 ± 0.3 5.9 ± 3.0 0.0 ± 0.0 2.6 ± 6.1 0.4 ± 0.0 21.7 ± 9.2 0.0 ± 0.0

LD-HE-F-E0-72 81 1.1 ± 3.3 68 ± 4 3.0 ± 1.5 70 ± 2 1.3 ± 3.2 96 ± 6 11.1 ± 4.7 31 ± 3

LD-HE-F-E10-72 64 0.4 ± 1.0 62 ± 4 1.0 ± 0.5 73 ± 2 0.4 ± 1.0 63 ± 4 3.5 ± 1.5 57 ± 6

LD-HE-F-E0-20 74 2.0 ± 5.7 62 ± 4 5.2 ± 2.6 68 ± 2 2.3 ± 5.4 75 ± 4 19.0 ± 8.1 31 ± 3

LD-HE-F-E10-20 76 0.2 ± 0.5 61 ± 4 0.4 ± 0.2 70 ± 2 0.2 ± 0.4 62 ± 4 1.6 ± 0.7 69 ± 7

LD-HE-A-E0-72 57 0.2 ± 0.6 64 ± 4 0.6 ± 0.3 61 ± 2 0.2 ± 0.6 67 ± 4 2.1 ± 0.9 59 ± 6

LD-HE-A-E10-72 53 0.5 ± 1.3 72 ± 4 1.2 ± 0.6 56 ± 2 0.5 ± 1.3 45 ± 3 4.5 ± 1.9 58 ± 6

LD-HE-A-E0-20 81 0.6 ± 1.9 72 ± 4 1.7 ± 0.9 73 ± 2 0.8 ± 1.8 57 ± 3 6.3 ± 2.7 83 ± 8

LD-HE-A-E10-20 47 0.7 ± 2.0 64 ± 4 1.8 ± 0.9 50 ± 1 0.8 ± 1.9 45 ± 3 6.5 ± 2.8 60 ± 6

Fuel Combustion and Lubrication Oil Contributions to Total Carbon (mg/mi) 2
99 

7.7 Light-Duty Gasoline Vehicles Major Technical Findings

Fresh and Aged oil

PM emissions nominally increased with aged oil in three of the four normal PM emitter 

(NE) test configurations (E10 at 20oF), but PM nominally decreased from the high PM emitter 

(HE) with aged oil.

E0 and E10 Fuel

PM emissions nominally increased with E10 from the normal emitter, but no trend was 

apparent with the high emitter.

Low and High Particulate Matter Emitter

The high PM emitter produced much higher rates of all emissions compared to the low 

emitter. PM rates were 20-400 times higher from the high emitter. 

Normal (72°F) and Low (20°F) Temperature

In the NE vehicle, PM emissions increased at low temperature compared to high 

temperature tests, as expected. In contrast, in the HE vehicle, PM nominally decreased at low 

temperature. The lack of PM response to temperature from the HE vehicle is an important 

finding relevant to modeling fleet emissions. Because high emitters contribute 

disproportionately, the temperature effects across a full range of moderate to high emitter 

vehicles should be studied to ensure accurate modeling of the fleet. 

Particle Number and Size Distributions

Particle Number (PN)

• The combination of cold-start and cold ambient temperature operation resulted in the highest 

PN emissions from the NE.

• The NE vehicle with fresh oil emitted higher number of solid and volatile particles, 

compared to emissions with the aged oil. This was observed at the cold-start and the hot-start 

portion of the drive cycle. 

• E10 resulted in higher particle emissions from the NE compared to E0, particularly at 72°F. 

At 20°F, there was not a consistent trend between E10 and E0. 

• Over 70 percent of the number of particles emitted from the NE were solid in nature. 

• The highest PN concentrations observed with the high emitter are a factor of 3000 and 30 

higher than the lowest and highest concentration observed with the NE, respectively. 

• Contrary to what was observed with the NE, the HE showed much higher particle number 

emissions with the aged oil, compared to that with the fresh oil. For the HE, there was not a 

difference in the PN emissions between the cold-start and the hot-start PN emissions using 

the fresh oil. 
100 

• The HE number emissions were dominated by volatile particles. With the fresh oil, more than 

65 percent of the particles were volatile in nature. With the aged oil, the number of volatile 

particles represents more than 85 percent of total particle number. This trend is opposite to 

what was observed with the NE, where solid particle number and mass dominate total PN 

and PM composition. 

Particle Size Distribution

• The total and solid distributions seem to exhibit a similar bimodal lognormal structure that 

consists of a nuclei mode <20 nm, and an accumulation mode. 

• For the fresh oil, the accumulation mode peaked at about 50 nm to 60 nm and the nuclei 

mode peaked at 10 nm. The accumulation mode for the aged oil was lower than the fresh oil 

in concentration, and it was at least 20 nm smaller in diameter than that for the fresh oil. 

Since the accumulation mode consists mainly of solid particles, the fresh oil seems to 

contribute to the formation and growth by coagulation of solid particles leading to a higher 

concentration and a larger particle size, compared with the aged oil. Filter measurements and 

OC/EC were inconsistent with these findings. Filter measurements showed higher PM with 

the aged oil, compared to the fresh oil. However, the reader should keep in mind that the size 

distribution data were taken for a limited number of tests, while the PM data were based on 

an interval of 16 different tests spanned over 16 days. 

• For the light-duty HE vehicle at 72°F, the size distributions are monomodal lognormal 

distributions. The accumulation mode for total particles peaks between 30 nm and 50 nm 

and is volatile in nature. This is different from the NE, where the accumulation mode was 

mainly composed of solid particles. For solid particle emissions from the HE, the distribution 

has a nuclei mode at 10 nm similar to that observed with the normal emitter. 

LD PM Apportionment

• Consistent with estimated high LOC rates, multiple linear regression results showed that 

nearly all of the exhaust PM from the LD high emitter was associated with lubrication oil.

• While the presence of elemental tracers and UCM alkanes indicates some contributions of 

the oil to exhaust PM for the normal emitter, the relative fuel and oil contributions are 

uncertain due to low emission levels.

• The emissions of semi-volatile PAHs for the NE vehicle exceeded particle-phase PAHs by 

approximately two orders of magnitude, and particulate OC by about a factor of two, 

indicating that the NE gasoline-powered vehicle may contribute more secondary organic 

aerosol precursor than direct PM.
101 

8.0 MEDIUM-DUTY VEHICLE TESTS

8.1 Vehicle Selection and Description

 Medium-duty vehicle selection was made in collaboration with the CLOSE Project 

Management Team. SwRI identified potential candidate medium-duty diesel vehicles for testing 

and made vehicle recommendations to the Project Management Team. We then waited for 

technical approval prior to procuring the test vehicles. 

8.1.1 Medium-Duty Vehicle Selection Criteria

SwRI used the light-duty vehicle selection criteria as guidelines for choosing the 

medium-duty vehicles. It was expected that the normal-emitting diesel vehicle would be 2002 

model year or newer with between 30,000 and 75,000 miles on the odometer. SwRI was to rent 

the vehicle from a local leasing agent that had been utilized in the past to procure medium-duty 

diesel pickup trucks. The high-emitting diesel vehicle was to be from a model year 1996 or older 

and known to emit high levels of PM, have high lubrication oil consumption, and/or have visible 

smoke related to lubrication oil. 

8.1.2 Medium-Duty Normal PM Emitter Vehicle Selection and Description 

SwRI made arrangements to lease the medium-duty (MD) normal PM emitting diesel, but 

upon delivery of vehicle that was originally chosen for the project we found that it was a 2008 

model equipped with a diesel particle filter (DPF). It was returned to the rental agency and a 

new search was begun for another MD diesel normal emitter.

The second medium-duty normal emitter we found, and subsequently tested, was a 2007 

3⁄4-ton pickup truck with 6.0L V8 engine. The engine was turbo-charged, and direct injected, 

with exhaust gas recirculation (EGR) and an oxidation catalyst for emissions control. It was 

rear-wheel drive and had a 3053 lb capacity (passengers and cargo). This vehicle was delivered 

to us with 57,665 miles on the odometer and returned with 59,031 miles.

8.1.3 Medium-Duty High PM Emitter Vehicle Selection and Description

SwRI spent three months searching for the high PM emissions medium-duty vehicle. We 

searched through Craigslist, Ebay, Autotrader, and newspapers. We spoke with dealers in San 

Antonio and Austin, wholesale dealers, the Texas Department of Transportation, and SwRI 

personnel and families.

The vehicle for the medium-duty high PM emitting (HE) was chosen from solicitations 

sent to SwRI employees and families. It was a one-owner 1989 3⁄4-ton pickup truck with a 7.3L 

V8 engine. The engine was naturally aspirated, with indirect fuel injection, and a 5-speed 

manual transmission. This engine had just less than 500,000 miles of operation and was all 

factory original under the valve covers. Nothing had been replaced in the long block of the 

engine. The fuel injector pump was replaced at about the 465,000 mile point. Oil consumption 
102 

was around 1/2 gallon (difference between full and add mark on the dip stick) per 3,000 miles. 

Most of this was consumed by the engine. There were some oil leaks, but they were not dripping 

to the ground when the engine was parked. 

Since the medium-duty high emitter had a standard transmission, the speed trace the 

driver follows for the UDC test cycle had to be augmented with transmission shift points for test 

repeatability purposes. The medium-duty high particulate emitter (MD-HE) was first driven on 

the road to find the transmission shift points associated with vehicle speed. We found that first 

gear is an ultra-low gear for use only during high-load low-speed operation. We decided not to 

use first gear during the emission test cycle. Transmission shift points were then added to the 

UDC trace based on acceleration requirements and vehicle speed, plus observation of the 

upcoming vehicle speeds in the UDC. We practiced the UDC and made notes on appropriate 

shift points which were then added to the driver’s trace. We then repeatedly practiced the trace 

and made adjustments to the shift points as needed for smooth vehicle operation. We found that 

the fourth gear synchronizers in the transmission were non-operative. We had to double clutch 

each shift into 4th gear during the tests. 

During practice tests, the left rear brake began to emit smoke. We removed the brake 

drum for inspection and replaced the brake pads, after which no further problems were 

experienced. Also, during initial practice operation the HE vehicle was found to be leaking 

hydraulic fluid from the power steering system, and leaking fuel from the fuel filter. Parts were 

ordered and repairs made to the power steering system and fuel filter to fix the leaks before 

emissions testing began.

8.1.4 Gaseous and PM Emissions Check-Out Tests

To assess the vehicle’s test repeatability, triplicate check-out tests of the medium-duty 

normal-emitting vehicle were performed with commercial Texas diesel fuel (TxLED), and as 

received lubricant. Each test consisted of a cold and hot start UDC performed after two initial 

preparatory tests and an overnight soak. Table 43 shows a summary of the results of these 

check-out tests. The vehicle’s emissions and fuel economy stability were good with the highest 

coefficient of variation calculated for particulate at 4.7 percent. Based on these results, the 

vehicle was approved for testing. 
103 

TABLE 43. CHECK-OUT TEST RESULTS FROM THE MEDIUM-DUTY NORMAL PM 

EMITTING VEHICLE EMISSIONS AND FUEL ECONOMY REPEATABILITY TESTS

Test 1 Test 2 Test 3 Average

Standard 

Deviation

Coefficient 

of 

Variation

HC, g/mile 0.416 0.418 0.440 0.425 0.013 3.1%

CO, g/mile 1.484 1.535 1.572 1.530 0.044 2.9%

NOx, g/mile 4.075 4.049 4.098 4.074 0.025 0.6%

PM, mg/mile 114.3 104.2 108.4 109.0 5.1 4.7%

Fuel Economy, 

mpg 13.48 13.27 13.56 13.44 0.15 1.1%

Note: These pre-check tests used different fuel than “for record” tests. These tests are not part of the particle characterization 

tests. Tests were performed at a nominal 72°F, with commercial fuel and lubricant as received.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, 

where n is the number of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the 

statistical significance of comparisons across different temperatures, fuels or lubricants cannot be rigorously verified.

Once the vehicle’s repairs were completed and the driver’s trace had been augmented 

with the shift schedule, emissions repeatability check out tests were performed with the 

candidate MD-HE diesel vehicle. Results of the emissions repeatability tests are shown in Table 

44. These results were sent to the CLOSE participants with the recommendation that we utilize 

it for the project. SwRI received approval to proceed with testing this MD-HE vehicle from the 

CLOSE Project technical team. 

TABLE 44. CHECK-OUT TEST RESULTS FROM THE MEDIUM-DUTY HIGH PM 

EMITTING VEHICLE EMISSIONS AND FUEL ECONOMY REPEATABILITY TESTS

MD-HE-FD-REP-2MD-HE-FD-REP-5MD-HE-FD-REP-6 AverageStandard 

Deviation

Coefficient 

of 

Variation

HC, g/mile 0.180 0.164 0.142 0.162 0.019 11.8%

CO, g/mile 1.264 1.281 1.278 1.274 0.009 0.7%

NOx, g/mile 7.429 7.826 7.582 7.612 0.200 2.6%

PM, mg/mile 464.2 574.8 386.9 475.3 94.4 19.9%

Fuel Economy, 

mpg 15.84 15.72 15.7 15.75 0.08 0.5%

Note: These check-out tests used different fuel than the “for record” tests. These tests are not part of the particle 

characterization tests. Tests were performed at a nominal 72°F, with commercial fuel and lubricant as received.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, 

where n is the number of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the 

statistical significance of comparisons across different temperatures, fuels or lubricants cannot be rigorously verified.

8.2 Lubricants

The medium-duty vehicles were tested with both fresh and aged lubricants. A description 

and the supplier’s analyses of the lubricants are included in Section 5.1 in Tables 3 and 5. The 

drain and fill and the lubricant’s initial degreening procedure is also described in Section 5.1. 

Oil samples include the fresh and aged oils as received, and samples taken after the cold (20°F) 
104 

tests with fresh and aged oils on diesel and B20 for both the normal and high emitter. For 

example, the normal emitter was operated over multiple emission tests with fresh oil and a 

sample was taken from the crankcase drain oil after the cold tests on diesel, and then the normal 

emitter was operated over multiple emissions tests with fresh oil on B20 and a sample was taken 

from the crankcase drain oil after the cold tests. Thus four oil samples were taken from the 

normal-emitter (two fuel types and two oils), and four oil samples were taken from the high 

emitter.

8.3 Fuels

The medium-duty vehicles were operated from test fuel installed in the on-board tanks. 

Test fuels are described in Section 5.2.2 in Table 11. Fuel systems on all vehicles were flushed

with the test fuels prior to the initiation of testing. The fuel flush procedure used for the 

medium-duty vehicles was the same one used for light-duty vehicles, as described in Section 7.3. 

8.4 Emission Test Procedures

This is a pilot study of exhaust emissions effects from the use of different fuels and 

lubricants with some tests conducted at different temperatures. It is important to note that the 

scope of work in this study is limited to short-term effects on emissions when a fuel or lubricant 

was changed. The fuels and lubricants used in this study could have long-term effects on 

emissions which were not measured.

8.4.1 Driving Cycle

Medium-duty vehicles were also tested over replicate cold-start Unified Driving Cycles 

(UDC). Thus, only one UDC per day was run. The UDC was conducted as a cold-start, fourphase test, in a manner similar to the light-duty Federal Test Procedure. The UDC consisted of a 

300-second cold-start phase (Bag 1) followed by an 1,135-second hot stabilized phase (Bag 2), a 

10-minute soak, and a hot-start phase (Bag 3) which is a repeat of the 300-second Bag 1, and a 

1,135-second hot stabilized phase (Bag 4) which is a repeat of Bag 2. For all emission tests, the 

vehicles were soaked for at least 12 hours at test temperature prior to emissions evaluations.

Both medium-duty vehicles were tested in SwRI’s Temperature Controlled Emissions 

Enclosure (TCEE), and exhaust samples were collected and analyzed in the same manner as for 

the light-duty gasoline vehicles. Sampling utilized an 18-inch diameter by 16-foot long stainless 

steel dilution tunnel and constant volume sampler. Tunnel cleaning and conditioning was 

conducted in the same manner as for the light-duty vehicles. A summary of the test matrix, 

tunnel blank and background sampling schedule, and tunnel cleaning and conditioning events are 

shown in the test matrix in Table 1. 

Based on previous testing of 3⁄4- and 1-ton diesel pickup trucks over both the FTP-75 and 

the UDC, SwRI expected that a single cold-start test cycle would be needed to collect sufficient 

sample mass for chemical analyses, and this was found to be correct. Thus, a total of 16 UDCs 

were conducted with each vehicle (1 UDC per sample × 2 oils × 2 fuels × 2 temperatures × 2 

replicate samples).
105 

Based on previous experience measuring vehicle PM exhaust emissions during programs 

conducted for NREL and CRC, it is possible for initial PM emission rates to be higher than those 

measured after a number of replicate tests. It was thought that the PM deposition mechanism in 

the vehicles’ exhaust systems may not have a chance to reach equilibrium during a standard 

vehicle preconditioning procedure. This effect could have a major impact on the results of this 

study; therefore, to minimize this effect SwRI performed a conditioning sequence of UDC runs 

with each vehicle prior to sample collection. This conditioning was conducted in conjunction 

with tunnel and sample system conditioning. 

8.4.2 Chassis Dynamometer

For medium-duty vehicles, a Clayton Model ECE-50 passenger car dynamometer with 

direct-drive variable inertia flywheel systems was used for testing. The inertia system on this 

dynamometer can simulate vehicle weights from 1,000 (lb-) up to 7,250 lb in 250-lb increments. 

The chassis dynamometer is located in the SwRI-built TCEE.

8.5 Emission Test Results

8.5.1 Regulated Gaseous and PM Mass Emissions

8.5.1.1 Medium-Duty Normal PM Emissions Vehicle

Composite filters were used during each test to capture PM during all four phases of the 

cold/hot UDCs. These composite filters were used for subsequent analyses at Desert Research 

Institute (DRI). During the initial check-out tests of the MD normal emitter, it was found that 

sufficient PM mass for subsequent analyses was captured on the composite filters during a single 

cold/hot UDC. Therefore, only two cold/hot UDCs were performed in each fuel, temperature, 

and oil test configuration to capture PM for later characterization. However, a third test was 

performed in order to complete three tests for particle number and size distribution.

Following approval of the vehicle for testing, it was then flushed with project test fuel 

(TxLED diesel), the engine was flushed with fresh lubricant with tracer, and the vehicle was 

driven for 150 miles on-road in order to perform an initial shear of the oil. The vehicle was then 

tested at nominal ambient temperatures of 72°F and 20°F. Summaries of the average results of

tests of the medium-duty normal emitter are shown in Tables 45 and 46, respectively.
106 

TABLE 45. MEDIUM-DUTY NORMAL PM EMITTING VEHICLE AT 72°F

(No Statistical Analyses Were Performed On These Data)

72°F -- Average of Duplicate Tests

TxLED Diesel B20

Fresh Oil Aged Oil Fresh Oil Aged Oil

Average 

Standard 

Deviation

Coefficient 

of Variation Average 

Standard 

Deviation

Coefficient 

of Variation Average 

Standard 

Deviation

Coefficient 

of Variation Average 

Standard 

Deviation

Coefficient 

of Variation

HC, g/mile 0.402 0.018 4.6% 0.398 0.021 5.3% 0.381 0.027 7.1% 0.375 0.007 1.9% 

CO, g/mile 1.503 0.038 2.5% 1.567 0.064 4.1% 1.416 0.062 4.4% 1.354 0.050 3.7%

NOx, g/mile 4.267 0.235 5.5% 4.347 0.240 5.5% 4.674 0.131 2.8% 4.400 0.049 1.1%

PM, mg/mile 112.5 13.5 12.0% 110.7 5.2 4.7% 96.4 1.41 1.5% 88.0 0.8 0.9% 

Fuel Economy, mpg 13.04 0.50 3.8% 13.56 0.01 0.1% 12.86 0.14 1.1% 13.80 0.50 3.6% 

a PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number 

of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across 

different temperatures, fuels or lubricants cannot be rigorously verified.

TABLE 46. MEDIUM-DUTY NORMAL PM EMITTING VEHICLE AT 20°F

(No Statistical Analyses Were Performed On These Data)

20°F -- Average of Duplicate Tests

TxLED Diesel B20 

Fresh Oil Aged Oil Fresh Oil Aged Oil

Average

Standard 

Deviation

Coefficient 

of Variation Average

Standard 

Deviation

Coefficient 

of Variation Average

Standard 

Deviation

Coefficient 

of Variation Average

Standard 

Deviation

Coefficient 

of Variation

HC, g/mile 0.507 0.030 6.0% 0.484 0.011 2.2% 0.499 0.001 0.3% 0.542 0.027 5.0% 

CO, g/mile 2.111 0.015 0.7% 2.103 0.085 4.0% 2.022 0.004 0.2% 2.085 0.099 4.7%

NOx, g/mile 6.780 0.115 1.7% 6.283 0.402 6.4% 6.479 0.582 9.0% 6.091 0.002 0.0% 

PM, mg/mile 169.4 15.6 9.2% 123.9 1.0 0.8% 129.8 5.3 4.1% 124.5 12.6 10.2%

Fuel Economy, mpg 11.97 0.00 0.0% 12.89 0.12 0.9% 12.12 0.36 3.0% 12.68 0.24 1.9% 

a PM as determined from phase-by-phase filter samples collected during each test.

These tests are not part of the particle characterization tests.

Tests were performed at a nominal 72°F, with commercial fuel and lubricant as received.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number 

of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across 

different temperatures, fuels or lubricants cannot be rigorously verified.

Composite filters were used during each test to capture PM during all four phases of the 

cold/hot UDCs and were then used in subsequent analyses at Desert Research Institute (DRI). 

These composite filters were compared to the phase-by-phase results shown in the summary 

tables after every test. To illustrate how the composite filters’ PM emission rates compare to the 

phase-by-phase filters’ rates, Table 47 shows the PM emission rates measured phase-by-phase 

and those collected as composites during all phases. All filters used to collect PM in Table 47 

are 47mm in diameter. The phase-by-phase and Teflon SwRI filters are of Teflon media with an 

outer polypropylene support ring. The Teflon DRI filters are Teflon media, and the Glass DRI 

filters are glass fiber filters. For comparison purposes, the data in Table 47 were graphed and are 

shown in Figure 43, which shows that the PM emission rates calculated with the various filter 

media were comparable to each other. The phase-by-phase and SwRI Teflon filters were similar 

media and measured similar PM rates. The glass DRI and the Teflon DRI filters typically 

measured nominally higher and lower than the SwRI filters, respectively.
107 

TABLE 47. SUMMARY OF PHASE-BY-PHASE AND COMPOSITE PM EMISSION

RATES FROM THE MEDIUM-DUTY NORMAL EMITTING VEHICLE

(No Statistical Analyses Were Performed On These Data)

PM Composite Results, mg/mile

Test Number Phase-By-Phase Teflon SwRI Glass DRI Teflon DRI

MD-NE-F-D-72-1 282.0 a 117.6 108.3 b 102.5 b

MD-NE-F-D-72-2 99.2 99.3

MD-NE-F-D-72-3 126.1 117.2 120.9 NA c

MD-NE-F-D-72-4 112.3 111.1 114.9 105.7

MD-NE-F-D-20-1 180.4 187.7 195.7 190.0

MD-NE-F-D-20-2 158.3 157.7 165.1 149.6

MD-NE-F-B20-72-1 97.4 93.3 94.1 88.1

MD-NE-F-B20-72-2 95.4 93.4 95.9 85.1

MD-NE-F-B20-20-1 126.0 124.2 128.1 118.7

MD-NE-F-B20-20-2 133.5 133.0 137.4 126.8

MD-NE-A-D-72-1 107.0 104.1 106.1 96.7

MD-NE-A-D-72-2 114.3 110.8 113.8 104.2

MD-NE-A-D-20-2 123.2 123.1 128.0 116.1

MD-NE-A-D-20-3 124.6 123.1 129.5 118.3

MD-NE-A-B20-72-3 87.4 94.4 95.4 101.8

MD-NE-A-B20-72-5 88.5 86.0 88.3 87.4

MD-NE-A-B20-20-2 137.7 140.4 143.8 133.1

MD-NE-A-B20-20-3 123.3 126.9 129.4 119.3 a Test MD-NE-F-D-72-1 Phase 1 PM mass was extremely high. b These filters were composited over two cold/hot UDCs. (MD-NE-F-D-72-1 and MD-NE-F-D-72-2). c 

 The filter sampling system failed to start during the cold/hot UDC.
108 

FIGURE 43. MEDIUM-DUTY NORMAL EMITTER PHASE-BY-PHASE

COMPOSITE FILTERS COMPARISON

(No Statistical Analyses Were Performed On These Data)

8.5.1.2 Medium-Duty High PM Emissions Vehicle

 Regulated gaseous and particle-phase emission rates along with fuel economy data from 

the medium-duty high PM emitter tests are shown in Tables 48 and 49 at room temperature and 

20°F, respectively. Both Tables 48 and 49 include results from the tests using TxLED diesel and 

B20 diesel with fresh and aged oils. 

TABLE 48. MEDIUM-DUTY HIGH PM EMITTING VEHICLE AT 72°F

(No Statistical Analyses Were Performed On These Data)

 

72°F -- Average of Duplicate Tests

TxLED Diesel B20 

Fresh Oil Aged Oil Fresh Oil Aged Oil

Average 

Standard 

Deviation

Coefficient 

of Variation Average 

Standard 

Deviation

Coefficient 

of Variation Average 

Standard 

Deviation

Coefficient 

of Variation Average 

Standard 

Deviation

Coefficient 

of Variation

HC, g/mile 0.195 0.008 4.4% 0.126 0.004 2.8% 0.131 0.004 2.7% 0.159 0.020 12.5% 

CO, g/mile 1.253 0.049 3.9% 1.291 0.018 1.4% 1.219 0.003 0.2% 1.323 0.002 0.2% 

NOx, g/mile 6.262 0.023 0.4% 7.672 0.134 1.8% 7.560 0.165 2.2% 6.387 0.108 1.7%

PM, mg/mile 408.4 13.2 3.2% 486.5 12.4 2.6% 446.2 10.4 2.3% 500.3 14.1 2.8% 

Fuel Economy, mpg 15.83 0.35 2.2% 16.64 0.05 0.3% 16.46 0.40 2.4% 16.77 0.19 1.1% 

a PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number 

of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across 

different temperatures, fuels or lubricants cannot be rigorously verified.

0.0

50.0

100.0

150.0

200.0

250.0

300.0

MDNE-FD-72-

1

MDNE-FD-72-

2

MDNE-FD-72-

3

MDNE-FD-72-

4

MDNE-FD-20-

1

MDNE-FD-20-

2

MDNE-FB20-

72-1

MDNE-FB20-

72-2

MDNE-FB20-

20-1

MDNE-FB20-

20-2

MDNE-AD-72-

1

MDNE-AD-72-

2

MDNE-AD-20-

2

MDNE-AD-20-

3

MDNE-AB20-

72-3

MDNE-AB20-

72-5

MDNE-AB20-

20-2

MDNE-AB20-

20-3

PM, mg/mile

Phase-by-phase Teflon SwRI Glass DRI Teflon DRI
109 

TABLE 49. MEDIUM-DUTY HIGH PM EMITTING VEHICLE AT 20°F

(No Statistical Analyses Were Performed On These Data)

20°F -- Average of Duplicate Tests

TxLED Diesel B20 

Fresh Oil Aged Oil Fresh Oil Aged Oil

Average

Standard 

Deviation

Coefficient 

of Variation Average

Standard 

Deviation

Coefficient 

of Variation Average

Standard 

Deviation

Coefficient 

of Variation Average

Standard 

Deviation

Coefficient 

of Variation

HC, g/mile 0.419 0.040 9.5% 0.305 0.044 14.4% 0.392 0.018 4.5% 0.389 0.018 4.6%

CO, g/mile 1.791 0.189 10.5% 1.904 0.128 6.7% 1.925 0.163 8.4% 2.039 0.149 7.3% 

NOx, g/mile 6.105 0.002 0.0% 7.741 0.173 2.2% 7.776 0.042 0.5% 7.509 0.230 3.1% 

PM, mg/mile 331.3 7.1 2.2% 351.9 27.0 7.7% 408.2 6.2 1.5% 429.2 31.6 7.4%

Fuel Economy, mpg 15.38 0.10 0.6% 15.57 0.03 0.2% 15.92 0.11 0.7% 15.28 0.49 3.2% 

a PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the number 

of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of comparisons across 

different temperatures, fuels or lubricants cannot be rigorously verified.

8.5.1.3 Discussion of Regulated Emissions Results 

Figure 44 presents the average hydrocarbon emissions from all the medium-duty vehicle 

tests. The normal PM emitter produced more hydrocarbon emissions than the high PM emitter in 

all configurations. The high PM emitter probably has more advanced fuel injection timing than 

the normal emitter which would have promoted more complete combustion of fuel. 

Hydrocarbon emissions increased in all configurations when either medium-duty vehicle was 

tested cold (20°F). Average rates of HC emissions were nominally lower with B20 fuel in the 

normal PM emitter from 72°F temperature tests, but no trend is evident due to the fuel change 

from cold test results. From the high PM emitter, HC emissions show no trends at any test 

temperature when comparing diesel to B20 fuel. There are no apparent trends in HC emissions 

from either vehicle when comparing average HC emissions from fresh and aged oil tests.

Figure 45 presents the average carbon monoxide emissions from all the medium-duty 

vehicle tests. The normal PM emitter produced more CO emissions than the high PM emitter in 

most configurations; the exception being aged oil tests on B20 fuel. With both fuels, CO 

emissions increased nominally in all configurations when either medium-duty vehicle was tested 

cold. Average rates of CO emissions were nominally lower with B20 fuel in the normal PM 

emitter from all tests except cold, aged oil tests. CO emissions from the high emitter show no 

trends at room temperatures when comparing diesel to B20 fuel. There are no apparent trends in 

CO emissions from the normal emitter when lubricant was changed from fresh to aged oils. 
110 

FIGURE 44. MEDIUM-DUTY VEHICLES’ AVERAGE HYDROCARBON

EMISSION RATES

(No Statistical Analyses Were Performed On These Data)

FIGURE 45. MEDIUM-DUTY VEHICLES’ AVERAGE CARBON MONOXIDE

EMISSION RATES

(No Statistical Analyses Were Performed On These Data)

0.40 0.51 0.38 0.50 0.40 0.48 0.38 0.54 0.20 0.42 0.13 0.39 0.13 0.31 0.16 0.39

-0.1

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

HC, g/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL

1.50 2.11 1.42 2.02 1.57 2.10 1.35 2.08 1.25 1.79 1.22 1.93 1.29 1.90 1.32 2.04

0.0

0.5

1.0

1.5

2.0

2.5

3.0

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

CO, g/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL
111 

Figure 46 presents the average oxides of nitrogen emissions from all the medium-duty 

vehicle tests. The normal PM emitter produced less NOX emissions than the high PM emitter in 

all but one configuration (cold tests with fresh oil on diesel fuel). Again, earlier fuel injection 

timing may have caused higher NOX emissions from the medium-duty high PM emitter. Overall, 

NOX emissions increased nominally in all cold (20°F) tests of the normal PM emitter, but did not 

generally increase in the high PM emitter. There are no apparent trends in average rates of NOX

emissions when we switched to B20 fuel in the normal PM emitter. From the high PM emitter,

NOX emissions nominally increased with B20 fuel on fresh oil, but nominally decreased with 

B20 fuels on aged oil. There are no apparent trends in emission rates from the high emitter when 

comparing average NOX emissions from fresh and aged oil tests.

Figure 47 presents the average fuel economies measured in all the medium-duty vehicle 

tests. Fuel economy from the high PM emitter was better in all test configurations. Again, 

earlier fuel injection timing may have produced better fuel economy with the medium-duty high 

PM emitter. Fuel economy nominally decreased in all cold temperature tests. There are no 

consistent trends in fuel economy when fuel was changed from diesel to B20 with either vehicle. 

Figure 48 presents the average PM emissions from all medium-duty vehicle tests. The 

high PM emitter produced higher PM rates in all configurations compared to the normal PM 

emitter. PM rates nominally increased in all cold (20°F) tests of the normal PM emitter, but 

decreased in all cold tests of the high PM emitter. We expect the PM from the high emitter to 

come primarily from the lubricant and, even though the engine comes up to a normal operating 

temperature, during the 20°F tests the lubricant remains cooler longer than during the 72°F tests. 

The cooler lubricant’s higher viscosity may reduce its flow into the combustion chamber whether 

from leaking intake valve guides or the piston’s oil control rings. This would reduce the PM 

rates during the cold tests. It is also possible that lubricants emitted during the cold tests coat 

and stay in the vehicle’s cold exhaust system. The nominal reduction of PM emissions during 

cold emission tests was also noted in the light-duty high emitter tests. With the normal emitter, 

in all tests but one (the normal emitter on aged oil during cold tests), the switch to B20 fuel 

nominally reduced the rate of PM emissions. Conversely, with the high PM emitter, the switch 

from diesel to B20 fuel nominally increased PM emissions.
112 

FIGURE 46. MEDIUM-DUTY VEHICLES’ AVERAGE OXIDES OF NITROGEN

EMISSION RATES

(No Statistical Analyses Were Performed On These Data)

FIGURE 47. MEDIUM-DUTY VEHICLES’ AVERAGE FUEL ECONOMY

(No Statistical Analyses Were Performed On These Data)

4.27 6.78 4.67 6.48 4.35 6.28 4.40 6.09 6.26 6.10 7.56 7.78 7.67 7.74 6.39 7.51

0

1

2

3

4

5

6

7

8

9

10

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

NOx, g/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL

13.0 12.0 12.9 12.1 13.6 12.9 13.8 12.7 15.8 15.4 16.5 15.9 16.6 15.6 16.8 15.3

0

5

10

15

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

FE, mpg

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL
113 

FIGURE 48. MEDIUM-DUTY VEHICLES’ AVERAGE

PARTICULATE MATTER EMISSION RATES

(No Statistical Analyses Were Performed On These Data)

8.5.2 PM and SVOC Analyses

Exhaust particles were characterized by analyzing them for elements, semi-volatile 

organic compounds (SVOC), elemental and organic compounds (EC/OC), sulfates, and soluble 

organic fraction (SOF) at DRI. In the following PM characterization subsections, Tables 50 

through 62 present the results of these PM characterizations. Data shown in Tables 50 through 

62 are the averages of the replicate tests performed in each configuration. 

The spreadsheet of light-duty PM analyses results which was devised by Dr. Fujita to 

investigate the light-duty PM characterization results was used as a template for the mediumduty PM characterization results. The spreadsheet includes the results from the individual tests, 

and is posted at an ftp site at SwRI for project participants. Dr. Lawrence Smith of SwRI 

collaborated with Dr. Fujita for the medium-duty vehicle PM apportionment analysis. They used 

the spreadsheet data to identify elements and compounds of interest in the apportionment study 

presented in Section 8.6.

113 169 96 130 111 124 88 125 408 331 446 408 487 352 500 429

0

100

200

300

400

500

600

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

D-72 D-20 B20-

72

B20-

20

PM, mg/mile

 

 

NORMAL PM EMITTER HIGH PM EMITTER

FRESH OIL AGED OIL FRESH OIL AGED OIL
114 

8.5.2.1 X-Ray Fluorescence (XRF)

Particles sampled from the medium-duty tests were analyzed by DRI for elements by 

XRF. Table 50 shows the average results in μg/mile of the replicate tests performed in each 

configuration. The configurations are identified in the top rows of the table, and elements 

measured are shown in the left column. Table 51 shows the results of fuels and lubricants 

analysis for elements by XRF.

8.5.2.2 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Analysis

 PM sampled from the medium-duty tests were analyzed by DRI for eighteen elements by 

ICP-MS. Table 52 shows the average results in μg/mile of the replicate tests performed in each 

configuration. The configurations are identified in the top rows of the table, and elements 

measured are shown in the left column. Table 53 shows the results of fuels and lubricants 

analysis for elements by ICP-MS.

8.5.2.3 Polycyclic Aromatic Hydrocarbons

Exhaust particles sampled from the medium-duty tests were analyzed by DRI for 

polycyclic aromatic hydrocarbons (PAH). Table 54 shows the average results in μg/mile of the 

replicate tests performed in each configuration. Table 28 shows the codes for the PAH species in 

Tables 54 and 55. Table 55 shows the results of fuels and lubricants analysis for PAHs.

8.5.2.4 Alkanes 

 PM sampled from the medium-duty tests were analyzed by DRI for alkanes. Table 56 

shows the average results in μg/mile of the replicate tests performed in each configuration. 

Table 30 shows the codes for the alkane species in Tables 56 and 57. 

Table 57 shows the results of alkane analyses of the fuels and lubricants from the 

medium-duty vehicles. The first eight columns identified by a test number are lubricant analyses 

from samples taken after the test in that configurations were completed. The last two columns 

show results of the medium-duty fuel analyses for alkanes.

8.5.2.5 Hopanes and Steranes

 PM sampled from the medium-duty tests were also analyzed by DRI for hopanes and 

steranes. Table 58 shows the average results in μg/mile of the replicate tests performed in each 

configuration. Table 33 shows the codes for the hopanes and steranes species in Tables 58 and 

59. Table 59 shows the results of fuels and lubricants analysis for hopanes and steranes. The 

high hopane levels for the MD-NE-A-B20 lubricant were noted and appear to be anomalous. 

Nevertheless these data were included in the average of total hopanes and steranes in the 

lubricants, and their average was used in the apportionment analysis in Section 8.6.5. 
115 

TABLE 50. AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE PM ELEMENTAL ANALYSIS BY XRF, μG/MI

(No Statistical Analyses Were Performed On These Data)

Test Number

MD-NE-FD-72MD-NEF-D-20MD-NE-FB20-72MD-NE-FB20-20MD-NEA-D-72MD-NEA-D-20MD-NEA-B20-72MD-NEA-B20-20MD-HEF-D-72MD-HEF-D-20MD-HEF-B20-72MD-HEF-B20-20MD-HEA-D-72MD-HEA-D-20MD-HE-AB20-72MD-HE-AB20-20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 

Temp, °F 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Na 40.24 84.03 128.20 40.91 111.24 57.00 59.05 34.43 0.00 101.49 60.92 100.23 0.00 68.61 1.72 279.91 

Mg 0.00 1.04 8.22 3.16 14.48 15.95 5.96 9.36 0.00 0.00 0.00 0.00 0.00 0.95 0.00 0.00

Al 9.28 5.73 0.29 1.43 14.15 9.98 2.70 0.00 0.00 0.00 0.00 9.24 0.00 0.00 0.00 6.93

Si 38.54 119.81 14.70 38.91 21.23 37.54 133.87 16.95 1.24 12.45 17.21 12.48 27.18 26.42 9.17 5.71 

P 56.05 297.67 42.16 122.13 26.24 87.11 24.74 79.59 351.80 484.36 364.22 477.72 349.90 436.36 360.32 549.83

S 203.19 980.02 86.35 363.76 81.82 277.93 102.48 209.49 325.65 471.44 251.57 422.59 364.32 516.62 4.03 221.17 

Cl 17.75 14.72 3.11 5.23 2.43 2.82 12.67 1.64 40.38 35.04 31.60 39.63 32.12 29.43 68.91 79.08

K 8.96 21.89 3.48 10.86 2.12 7.18 19.52 4.21 9.95 9.27 9.86 12.58 10.53 11.24 7.04 12.82

Ca 199.23 909.66 107.67 342.39 76.37 263.44 86.72 225.39 612.38 831.66 606.09 792.17 745.83 885.59 815.68 1181.70 

Sc 0.00 0.00 0.00 0.64 0.00 0.00 0.67 0.18 5.76 20.13 11.01 4.85 36.06 46.17 25.64 13.88

Ti 1.62 4.14 0.02 2.21 0.12 0.95 1.67 0.00 1.69 1.26 1.26 1.68 3.35 0.02 4.78 6.90 

Va 0.15 0.47 0.00 0.43 0.12 0.30 0.00 0.00 0.18 0.00 0.00 0.61 0.00 0.00 0.00 0.26

Cr 20.76 83.97 5.20 20.62 4.69 16.03 10.51 9.84 6.18 6.16 6.50 9.85 5.75 4.58 12.34 9.89

Mn 15.92 30.44 1.81 10.90 2.27 10.63 36.78 2.55 10.81 8.80 6.45 11.92 3.30 7.33 2.59 21.80 

Fe 621.42 2616.38 176.45 803.78 182.33 590.56 307.71 322.69 241.94 532.90 359.00 396.00 193.01 314.58 1305.59 1690.75

Co 0.00 0.00 0.13 0.00 0.24 0.00 0.00 0.00 0.00 0.00 0.81 1.04 0.84 0.78 0.00 0.00 

Ni 6.56 20.46 1.30 6.63 1.25 5.43 5.23 2.36 3.63 5.22 1.98 6.56 2.91 4.94 23.48 21.38

Cu 9.11 23.43 4.39 10.38 3.68 10.48 7.41 10.20 6.39 10.56 18.97 29.39 8.06 13.77 38.35 58.87

Zn 125.02 437.39 84.54 192.36 49.16 130.88 56.69 135.97 418.46 630.55 408.72 542.59 442.58 512.92 469.33 824.84 

Ga 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.89 0.00 0.00 0.00 0.00 0.00 0.00 0.05

As 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.28 0.00 0.00 0.00 0.00 10.79 

Se 0.00 0.00 0.00 0.05 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Br 0.35 0.65 0.34 1.17 0.26 1.00 1.24 0.08 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Rb 0.00 1.28 0.22 0.09 0.00 0.00 0.32 0.40 0.66 0.00 0.48 0.03 1.27 0.54 0.00 1.04 
116 

TABLE 50 (CONT'D). AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE PM ELEMENTAL ANALYSIS BY XRF, μg/mi 

(No Statistical Analyses Were Performed On These Data)

TEST 

NUMBER 

MD-NE-FD-72MD-NEF-D-20MD-NE-FB20-72MD-NE-FB20-20MD-NEA-D-72MD-NEA-D-20MD-NEA-B20-72MD-NEA-B20-20MD-HEF-D-72MD-HEF-D-20MD-HEF-B20-72MD-HEF-B20-20MD-HEA-D-72MD-HEA-D-20MD-HE-AB20-72MD-HE-AB20-20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 

Temp, °F 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Sr 0.07 0.00 0.00 0.00 0.03 0.00 0.14 0.27 1.52 2.51 0.99 1.17 1.41 2.14 0.51 1.55 

Yt 0.00 0.00 0.24 0.00 0.03 0.00 0.11 0.00 1.35 0.89 0.00 0.00 0.22 0.47 0.00 0.37

Zr 9.79 3.29 0.16 1.68 2.17 0.00 2.24 0.38 0.29 0.78 0.00 0.00 0.56 0.00 0.00 1.88

Nb 0.11 0.13 0.00 0.00 0.29 0.00 0.00 0.00 0.00 1.11 0.00 1.16 0.89 0.08 1.52 0.00 

Mo 5.32 22.32 0.88 3.64 0.57 3.35 0.20 1.63 0.38 0.48 0.95 0.50 2.49 0.29 5.35 1.10

Pd 0.28 1.01 2.19 1.03 0.07 0.00 0.00 0.00 0.00 0.00 0.00 0.08 0.00 0.00 0.00 0.00 

Ag 0.00 0.68 0.07 1.10 0.00 1.43 0.00 0.21 0.99 0.00 1.95 3.07 0.00 0.00 0.00 0.75

Cd 0.36 0.00 0.00 0.62 0.57 0.43 0.00 0.00 2.64 0.00 0.00 0.00 0.00 0.00 0.00 0.00

In 1.15 0.00 0.60 0.85 0.00 0.00 0.71 0.00 0.00 0.00 0.18 0.54 0.00 0.00 0.00 0.00 

Sn 0.93 0.92 1.26 0.87 0.00 1.13 0.00 0.00 0.00 5.34 9.53 4.31 0.13 1.39 0.00 0.00

Sb 0.45 1.00 1.38 0.50 0.00 0.00 0.00 1.16 0.52 1.94 0.00 4.86 0.00 0.00 0.00 2.37 

Cs 1.34 0.09 0.81 2.00 0.86 2.12 0.09 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Ba 1.54 0.00 2.57 0.00 0.00 0.00 1.20 0.00 2.01 8.40 9.02 11.10 2.54 0.00 7.31 0.98

La 0.00 0.00 2.59 0.00 1.42 3.09 5.79 4.58 22.95 10.36 0.00 0.00 12.76 3.37 0.00 0.00 

Ce 0.00 1.66 2.38 0.00 0.00 0.00 3.05 1.76 25.06 0.00 7.40 7.59 10.04 7.94 0.41 13.69

Sm 1.56 0.00 0.79 0.00 4.22 0.00 3.30 1.00 27.33 0.00 3.21 0.00 22.98 0.00 0.00 0.00 

Eu 0.82 9.47 0.00 12.39 11.72 12.37 4.32 13.16 9.10 5.38 0.00 20.52 20.32 38.06 11.86 0.00

Tb 6.11 0.00 9.12 0.00 2.16 19.59 17.28 19.18 25.69 0.00 7.75 8.81 33.60 22.34 38.31 10.73

Hf 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.19 8.20 1.54 0.00 6.24 10.02 0.00 0.00 

Ta 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 17.70 20.67 16.74 10.79 19.08 1.55 5.77 10.39

Wo 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.75 3.81 0.00 1.45 

Ir 0.00 0.00 0.22 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5.63 0.00

Au 0.39 0.33 0.79 1.09 0.00 0.41 0.97 0.30 0.00 0.00 0.16 0.00 0.00 0.00 0.00 0.00

Hg 0.19 0.53 0.33 0.00 0.65 0.00 0.03 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 

Tl 0.00 0.00 0.04 0.00 0.17 0.41 0.00 0.10 0.00 0.00 0.62 0.00 0.00 0.00 0.99 0.00

Pb 1.30 2.49 0.72 3.24 0.21 2.16 0.35 0.92 3.77 27.04 121.78 168.74 24.02 40.32 1135.16 1004.56 

U 0.00 0.00 0.77 0.00 0.12 0.00 0.13 0.01 2.49 2.77 2.78 2.76 2.29 0.00 2.79 0.00
117 

TABLE 51. MEDIUM-DUTY VEHICLE LUBRICANTS AND FUELS ELEMENTS BY XRF

(No Statistical Analyses Were Performed On These Data)

Lubricant Elements, μg/gram

Fuel Elements, 

μg/gram

Test Number

MD-NEF-DMD-NEF-B20MD-NEA-DMD-NEA-B20MD-HEF-DMD-HEF-D REPMD-HEF-B20MD-HEA-DMD-HEA-B20EM6952-FEM7002-F

Emitter Normal Normal Normal Normal High High High High High Both Both 

Oil Fresh Fresh Aged Aged Fresh Fresh Fresh Aged Aged Both Both

Fuel Diesel B20 Diesel B20 Diesel Diesel B20 Diesel B20 Diesel B20 

Temp, oF 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Na 0 0 0 0 0 0 0 0 0 0 0

Mg 0 0 0 0 0 0 0 0 0 0 0 

Al 0 0 0 0 0 0 0 0 0 0 0

Si 0 0 0 0 0 0 0 0 0 0 0 

P 168 176 169 143 173 190 205 164 170 0 2

S 2741 2587 2768 2727 2416 2545 2639 2608 2644 0 0 

Cl 0 0 0 0 0 0 0 0 0 0 0

K 0 0 0 0 0 0 0 0 0 0 0 

Ca 2242 2254 2337 2714 2129 2296 2161 2220 2236 0 0

Sc 0 0 0 0 0 0 0 0 0 0 0 

Ti 0 0 0 0 0 0 0 0 0 0 0

Va 0 0 0 0 0 0 0 0 0 0 0 

Cr 1 1 3 4 1 2 1 2 3 0 0

Mn 0 1 1 1 0 1 0 0 0 0 0 

Fe 5 4 38 83 11 41 6 33 50 0 0

Co 0 0 0 0 0 0 0 0 0 0 0 

Ni 0 0 0 1 0 0 0 0 0 0 0

Cu 0 0 0 5 0 0 0 0 6 0 1 

Zn 1433 1434 1515 1551 1444 1511 1461 1496 1559 0 0

Ga 0 0 0 0 0 0 0 0 0 0 0 

As 0 0 0 0 0 0 0 0 0 0 0

Se 0 0 0 0 0 0 0 0 0 0 0 

Br 0 0 0 0 0 0 0 0 0 0 0

Rb 0 0 0 0 0 0 0 0 0 0 0 

Sr 0 0 0 0 0 0 0 0 0 0 0

Yt 0 0 0 0 0 0 0 0 0 0 0 

Zr 0 0 0 0 0 0 0 0 0 0 0

Nb 0 0 0 0 0 0 0 0 0 0 0 

Mo 0 0 0 6 1 0 0 0 0 0 0
118 

TABLE 51 (CONT'D). MEDIUM-DUTY VEHICLE LUBRICANTS AND FUELS ELEMENTS

BY XRF

(No Statistical Analyses Were Performed On These Data)

Lubricant Elements, μg/gram 

Fuel Elements, 

μg/gram 

Test Number

MD-NEF-DMD-NEF-B20MD-NEA-DMD-NEA-B20MD-HEF-DMD-HEF-D REPMD-HEF-B20MD-HEA-DMD-HEA-B20EM6952-FEM7002-F

Emitter Normal Normal Normal Normal High High High High High Both Both

Oil Fresh Fresh Aged Aged Fresh Fresh Fresh Aged Aged Both Both

Fuel Diesel B20 Diesel B20 Diesel Diesel B20 Diesel B20 Diesel B20

Temp, oF 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Pd 0 0 0 0 0 0 0 0 0 0 0

Ag 0 0 0 0 0 0 0 0 0 0 0 

Cd 0 0 0 0 0 0 0 0 0 0 0

In 0 0 0 0 0 0 0 0 0 0 0 

Sn 0 0 0 0 0 0 0 0 0 0 0

Sb 0 0 0 0 0 0 0 0 0 0 0 

Cs 0 0 0 0 0 0 0 0 0 0 0

Ba 0 0 0 0 0 0 0 0 0 0 0 

La 0 0 0 0 0 0 0 0 0 0 0

Ce 0 0 0 0 0 0 0 0 0 0 0 

Sm 0 0 0 0 0 0 0 0 0 0 0

Eu 0 0 0 0 0 0 0 0 0 0 0 

Tb 0 0 0 0 0 0 0 0 0 0 0

Hf 0 0 0 0 0 0 0 0 0 0 0 

Ta 0 0 0 0 0 0 0 0 0 0 0

Wo 0 0 0 0 0 0 0 0 0 0 0 

Ir 0 0 0 0 0 0 0 0 0 0 0

Au 0 0 0 0 0 0 0 0 0 0 0 

Hg 0 0 0 0 0 0 0 0 0 0 0

Tl 0 0 0 0 0 0 0 0 0 0 0 

Pb 0 0 4 7 0 4 0 4 6 0 0
119 

TABLE 52. AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE PM ELEMENTAL ANALYSIS BY ICP-MS, μg/mi

(No Statistical Analyses Were Performed On These Data)

TEST 

NUMBER

MD-NE-F-D72MD-NE-FD-20

MDNE-FB20-72MDNE-FB20-20MDNE-AD-72-1MDNE-AD-20-2MDNE-AB-20-72MDNE-AB-20-20MDHE-FD-72MDHE-FD-20MDHE-FB20-72MDHE-FB20-20MDHE-AD-72MDHE-AD-20MD-HEA-B20-

72

MDHE-AB20-20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20

Temp, F 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Mg 3.91 14.94 3.69 4.05 1.38 4.03 6.05 2.21 2.60 4.67 3.32 8.52 0.16 6.79 3.41 3.53

Al 20.29 51.01 65.54 22.49 8.95 34.47 43.55 5.77 34.64 38.53 10.99 16.63 9.66 69.39 0.60 30.00 

Ca 179.99 869.80 158.23 324.96 92.23 281.79 114.10 239.28 157.12 243.72 163.90 199.11 219.83 245.31 187.45 266.66 

Va 0.14 0.38 0.03 0.10 0.07 0.12 1.20 0.09 0.02 0.19 0.02 0.02 0.01 0.01 0.00 0.02 

Cr 21.08 38.11 4.45 10.80 6.86 18.43 13.58 7.26 9.61 4.14 6.23 0.25 0.00 0.00 0.00 2.06 

Mn 6.88 16.29 3.03 7.51 1.88 7.64 38.16 4.50 4.21 4.17 3.29 3.93 2.55 3.46 3.75 7.64

Fe 381.16 1649.75 141.42 460.63 134.80 418.68 451.96 258.29 154.75 347.38 181.62 236.03 113.21 205.32 499.19 910.80

Ni 9.62 15.09 3.06 5.39 1.39 10.69 8.45 2.10 2.43 3.54 1.66 3.22 1.35 3.51 7.39 14.68

Cu 4.39 16.30 5.64 6.11 1.72 7.61 9.24 8.19 29.79 71.71 43.04 21.70 6.02 8.54 39.11 44.86

Zn 103.69 326.61 72.79 150.58 42.04 106.64 55.37 117.22 344.67 566.45 344.82 458.99 376.07 453.36 401.91 678.76

Mo 2.94 12.12 0.67 3.13 0.50 2.45 0.72 1.35 0.25 0.65 0.09 0.24 0.02 0.15 0.69 0.92

Ag 0.07 0.12 0.00 0.41 0.00 0.11 0.77 0.01 0.05 0.07 0.01 0.00 0.00 0.00 0.13 0.00 

Cd 0.21 0.34 0.04 0.04 0.01 0.01 0.19 0.00 0.18 0.50 0.40 0.68 0.12 0.13 1.35 1.84 

Sn 0.95 1.77 0.54 0.77 0.19 0.41 0.52 0.36 2.47 6.88 7.50 12.89 2.05 2.21 27.10 36.21 

Ba 2.59 3.58 0.70 0.61 0.86 2.11 1.85 0.25 1.65 0.82 5.43 1.68 1.75 1.01 3.72 5.28 

Ce 0.76 4.18 0.18 1.07 0.09 1.14 0.59 0.64 0.16 0.08 0.14 0.08 0.07 0.07 0.10 0.09

Hg 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Pb 0.48 2.39 0.39 0.74 0.21 0.72 0.66 0.75 6.07 24.56 108.97 144.47 22.53 31.68 1039.83 822.61
120 

TABLE 53. MEDIUM-DUTY VEHICLE LUBRICANTS AND FUELS ELEMENTS BY ICP-MS

(No Statistical Analyses Were Performed On These Data)

Lubricants, ng/gram Fuels, ng/gram

Test 

Number MD-NE-F-D REP1 MD-NE-F-D REP2 MD-NE-A-D MD-NE-F-B20 MD-NE-A-B20 EM-6952-F REP1 EM-6952-F REP 2 EM-7002-F

Emitter Normal Normal Normal Normal Normal Both Both Both

Oil Fresh Fresh Aged Fresh Aged Both Both Both

Fuel Diesel Diesel Diesel B20 B20 Diesel Diesel B20

Temp, F 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Mg 7546 7580 6631 6346 8899 <LOD <LOD 75 

Al 1334 1377 3745 1324 2949 84 <LOD <LOD

Ca 1835432 1871243 2078633 1912186 2344386 <LOD <LOD 1145 

V 46 48 38 51 101 <LOD <LOD <LOD

Cr 102 112 991 102 1751 <LOD <LOD 4 

Mn 89 91 276 92 580 <LOD <LOD 3 

Fe 3604 3684 28330 3071 54945 168 196 221 

Ni 58 87 350 97 1715 <LOD <LOD <LOD

Cu 172 157 4976 136 8843 <LOD <LOD 5 

Zn 1187007 1241977 1389552 1224397 1326866 <LOD <LOD 29 

Mo 623 561 238 162 4661 <LOD <LOD <LOD

Ag <LODa <LOD 7 <LOD 4 <LOD <LOD <LOD

Cd NMb NM NM NM NM NM NM NM

Sn NM NM NM NM NM NM NM NM

Ba 21 24 97 10 383 <LOD <LOD <LOD

Ce NM NM NM NM NM NM NM NM

Hg NM NM NM NM NM NM NM NM

Pb 191 215 3666 150 6075 <LOD <LOD 1 

W <LOD <LOD 8 <LOD 3 <LOD <LOD <LOD

P 1002286 1018522 1038864 1057434 1061213 <LOD <LOD <LOD

S 3029208 3163322 3278174 3123138 3589616 6002 6435 4793 

Ti 32 26 60 30 64 <LOD <LOD <LOD

Sr 782 837 1044 885 806 <LOD <LOD <LOD

a Less than level of detection

b Not measured
121 

TABLE 54. AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE EXHAUST POLYCYCLIC AROMATIC HYDROCARBONS, 

μg/mi

(No Statistical Analyses Were Performed On These Data)

Test Number

MD-NEF-D-72MD-NEF-D-20

MD-NEF-B20-

72

MD-NEF-B20-

20

MD-NEA-D-72MD-NEA-D-20

MD-NEA-B-20-

72

MD-NEA-B-20-

20

MD-HEF-D-72MD-HEF-D-20

MD-HEF-B20-

72

MD-HEF-B20-

20a

MD-HEA-D-72MD-HEA-D-20

MD-HEA-B20-

72

MD-HEA-B20-

20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High 

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged 

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20

Temp, °F 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Media F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD 

TB Correction Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes 

naphth 496.0 882.7 429.8 552.8 528.5 836.4 196.6 333.1 581.3 1233.8 367.7 1288.6 370.0 1229.3 472.5 1025.9 

quinoline 14.7 28.0 11.6 5.9 14.8 18.3 6.5 3.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 

mnaph2 376.4 531.8 272.5 285.7 371.8 439.6 116.7 138.0 115.7 290.7 62.3 349.1 65.7 336.4 81.8 240.5 

mnaph1 243.6 332.8 173.1 181.7 236.5 278.0 76.2 95.9 86.0 215.9 48.4 246.5 50.9 250.1 59.8 169.8 

biphen 80.4 135.2 63.9 72.0 76.8 94.3 25.5 36.3 25.5 65.4 16.4 79.7 15.4 73.9 20.9 56.5 

m_2bph 0.0 0.0 75.2 24.2 44.2 96.5 83.2 12.5 197.5 167.1 114.0 211.9 40.8 179.9 0.0 24.9 

dmn267 184.5 257.8 132.9 134.5 183.8 199.0 57.9 60.7 28.4 89.5 19.3 143.7 20.6 113.1 26.5 79.5 

dm1367 282.2 389.1 252.3 252.4 354.7 381.1 105.3 110.8 51.7 176.5 31.6 283.1 37.8 219.2 50.1 152.8 

d14523 124.6 169.7 86.1 84.0 121.1 128.4 37.8 36.1 17.2 58.5 10.9 93.6 13.6 73.9 16.3 48.9 

enap12 78.9 108.3 67.9 65.4 89.9 103.6 32.3 36.3 26.0 60.9 17.2 75.9 15.4 68.7 16.9 49.6 

acnapy 45.8 101.5 42.0 56.7 43.4 71.2 15.3 30.5 43.2 116.8 29.6 106.3 47.4 103.5 51.7 76.2 

dmn12 40.5 57.1 29.3 28.6 40.2 42.5 10.5 11.0 6.6 23.4 4.0 38.6 4.5 29.4 7.5 19.3 

dmn18 0.4 1.4 0.6 1.8 0.8 0.7 0.6 0.4 0.0 0.0 0.0 0.6 0.2 0.6 0.1 0.0 

acnape 3.5 5.6 2.2 3.1 3.1 4.6 1.1 1.4 7.7 17.8 5.5 20.0 3.3 19.1 4.4 12.1 

m_3bph 32.7 88.5 83.3 68.6 105.0 145.4 58.9 27.5 91.3 109.5 58.3 134.3 21.8 130.3 14.0 44.3 

m_4bph 7.7 32.7 30.9 24.8 32.0 47.4 15.2 4.3 24.3 40.6 18.3 52.6 7.4 43.5 4.5 18.5 

dbzfur 17.8 27.0 14.5 13.7 15.8 17.9 5.3 6.6 7.1 14.7 4.8 15.6 4.3 20.0 6.4 12.7 

em_12n 17.0 27.2 15.0 13.8 24.2 23.4 9.0 7.8 19.6 46.4 13.2 56.5 12.0 60.4 18.1 41.1 

tmi235n 46.8 80.1 45.3 43.5 60.3 66.5 18.3 23.4 10.3 36.8 8.8 61.0 10.8 48.6 16.5 38.2 

btmnap 70.4 93.4 57.3 55.9 75.6 84.2 27.5 29.3 12.1 42.3 10.8 84.3 14.5 62.1 15.6 42.0 

atmnap 78.5 111.6 64.2 61.1 76.0 93.9 31.5 32.5 20.5 62.8 18.2 95.2 21.0 81.0 27.6 57.3 

ctmnap 77.6 100.9 63.6 62.5 84.2 90.5 32.0 34.1 17.6 48.1 11.7 87.0 16.2 66.8 20.5 48.9 

em_21n 6.9 10.1 3.5 2.7 5.5 4.1 1.7 0.4 1.0 2.9 0.9 1.6 0.4 5.0 0.9 3.0 

etmnap 45.3 64.9 38.9 39.7 41.6 56.8 18.5 21.2 10.0 31.5 7.0 55.7 10.1 40.3 12.9 33.0 

tm245n 9.6 13.2 12.5 4.8 14.2 12.4 4.0 7.1 5.0 10.9 2.7 19.8 3.8 16.7 6.9 12.8 
122 

TABLE 54 (CONT'D). AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE EXHAUST POLYCYCLIC AROMATIC 

HYDROCARBONS, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test Number

MD-NEF-D-72MD-NEF-D-20

MD-NEF-B20-

72

MD-NEF-B20-

20

MD-NEA-D-72MD-NEA-D-20

MD-NEA-B-20-

72

MD-NEA-B-20-

20

MDHE-FD-72MDHE-FD-20MDHE-FB20-72MDHE-FB20-20aMDHE-AD-72MDHE-AD-20MDHE-AB20-72MDHE-AB20-20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High 

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged 

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20

Temp, °F 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Media F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD 

TB Correction Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes 

ftmnap 35.7 49.6 27.7 29.2 39.7 41.0 14.6 16.5 7.2 22.1 7.0 40.1 7.9 28.1 11.3 24.4 

fluore 9.7 18.3 7.6 10.4 9.3 17.7 3.6 9.1 18.8 50.6 14.5 51.3 12.5 51.3 23.1 53.7 

tm145n 5.8 10.4 5.0 4.5 7.2 9.6 2.2 2.1 2.7 7.7 1.1 6.4 0.7 10.1 1.3 8.5 

jtmnap 24.7 36.7 17.7 19.3 29.2 32.2 8.4 11.4 4.5 16.9 3.6 29.7 5.7 21.1 4.0 13.8 

a_mfluo 4.3 14.8 3.7 6.7 4.5 9.5 1.1 1.2 4.0 16.9 2.3 28.4 4.7 23.4 10.4 16.5 

b_mfluo 4.7 7.9 3.2 2.5 3.9 6.1 1.8 1.1 0.2 4.6 0.4 3.6 0.9 4.8 2.4 3.9 

m_1fluo 10.3 17.6 10.3 7.6 10.1 12.4 2.7 3.1 3.9 12.9 3.5 17.1 6.8 20.6 10.4 16.7 

fl9one 2.5 1.8 1.5 0.9 1.9 3.1 0.3 0.5 29.4 24.4 25.6 10.3 28.4 30.1 29.0 29.3 

phenan 15.7 55.1 13.3 24.3 19.3 47.4 4.0 13.2 138.8 154.7 136.1 164.3 153.8 160.9 164.4 175.4 

anthra 3.3 6.9 3.9 4.0 4.1 7.6 1.8 1.8 18.0 17.6 18.1 19.7 21.0 17.7 21.3 21.9 

xanone 2.0 2.7 0.5 1.1 1.0 1.7 0.4 0.7 1.6 8.7 1.8 16.5 3.7 10.2 6.0 9.4 

acquone 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 

m_2phen 1.4 3.9 1.2 1.9 1.8 2.8 0.7 0.0 26.4 24.5 30.1 28.9 36.3 35.6 41.8 35.5 

m_3phen 5.7 8.0 5.2 3.9 5.7 7.3 2.5 2.2 34.6 30.2 38.4 39.0 46.1 41.3 51.6 45.2 

pnapone 13.3 12.0 8.7 7.5 14.4 17.1 9.8 13.7 65.0 61.6 59.8 55.4 80.8 69.7 74.4 76.9 

m_2anth 0.4 0.8 0.2 0.7 0.6 0.4 0.2 0.2 3.5 3.0 4.3 3.6 4.9 5.2 6.1 4.0 

m_45phen 0.0 3.5 0.2 1.6 0.3 3.2 0.0 1.0 8.3 16.2 12.1 21.3 16.3 18.8 20.1 25.6 

m_9phen 2.8 4.3 2.7 1.9 3.0 4.4 1.1 0.5 15.9 16.6 16.0 17.6 21.6 20.6 23.0 20.8 

mpht_1 0.0 1.4 0.0 0.2 0.1 0.0 0.0 0.0 15.1 15.4 15.9 18.7 20.7 19.8 22.2 20.8 

anthron 0.4 1.3 0.6 0.7 0.8 0.5 1.7 0.0 0.3 3.4 0.5 2.8 0.4 1.4 2.5 4.1 

m_9ant 0.3 0.4 0.0 0.2 0.1 0.2 0.1 0.1 0.2 1.0 0.5 0.8 0.5 0.7 0.5 0.9 

nap2phen 0.0 1.6 0.1 0.7 0.0 1.4 0.1 0.1 9.8 11.2 10.4 14.8 16.4 13.0 16.9 19.6 

anrquone 5.2 6.7 4.7 4.6 6.8 7.5 6.1 6.2 18.7 17.5 15.8 21.0 22.7 18.2 18.3 20.8 

a_dmph 0.6 1.5 0.4 0.7 1.0 1.2 0.0 0.5 10.7 10.5 11.1 14.4 15.0 15.2 17.5 17.6 

b_dmph 0.3 0.6 0.3 0.1 0.5 0.8 0.0 0.2 6.3 6.0 6.7 8.3 9.0 9.3 10.4 10.4 
123 

TABLE 54 (CONT'D). AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE EXHAUST POLYCYCLIC AROMATIC 

HYDROCARBONS, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test Number

MD-NEF-D-72MD-NEF-D-20

MD-NEF-B20-

72

MD-NEF-B20-

20

MD-NEA-D-72MD-NEA-D-20

MD-NEA-B-20-

72

MD-NEA-B-20-

20

MD-HEF-D-72MD-HEF-D-20

MD-HEF-B20-

72

MD-HEF-B20-

20a

MD-HEA-D-72MD-HEA-D-20

MD-HEA-B20-

72

MD-HEA-B20-

20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High 

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged 

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20

Temp, °F 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Media F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD 

TB Correction Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes 

dm17ph 1.6 1.2 1.0 0.9 1.2 1.9 0.1 0.0 48.3 52.7 44.8 66.6 71.7 78.1 84.4 86.8 

dm36ph 0.9 1.5 0.5 0.6 0.5 1.7 0.2 0.3 5.9 7.2 6.9 8.7 13.3 11.7 12.5 11.3 

d_dmph 1.6 1.8 1.4 1.2 1.7 2.0 1.2 1.4 5.6 6.6 5.0 7.6 7.8 8.3 8.5 8.5 

e_dmph 0.9 1.4 1.0 0.5 1.1 1.3 0.4 0.8 4.1 4.1 4.1 4.5 5.7 5.8 6.3 5.5 

c_dmph 3.8 4.7 3.2 2.6 3.8 4.6 1.7 2.5 15.3 17.5 14.5 23.1 22.6 23.6 24.5 27.2 

fluora 0.0 14.8 0.1 8.0 1.2 15.7 0.0 11.5 68.8 96.8 69.8 116.3 102.4 87.8 104.1 162.7 

pyrene 0.9 16.2 0.9 9.7 2.2 16.9 1.4 14.3 97.8 134.0 91.5 142.0 135.2 124.6 147.3 212.5 

antal9 0.2 0.6 0.6 0.9 0.2 0.8 0.5 0.3 3.0 4.8 2.7 5.7 4.2 5.9 4.6 7.0 

retene 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 

bafluo 0.0 0.5 0.1 0.4 0.2 1.1 0.1 0.6 3.1 7.4 2.3 7.9 3.5 6.7 5.3 12.3 

bbfluo 0.1 0.2 0.0 0.2 0.1 0.2 0.1 0.5 0.4 1.5 0.5 2.2 0.7 1.6 1.4 4.8 

bmpyfl 0.1 0.5 0.2 0.5 0.3 1.3 0.1 0.9 0.0 0.0 0.0 0.1 0.0 0.1 0.0 0.1 

c1mflpy 0.2 0.6 0.2 0.4 0.3 0.9 0.3 0.5 4.5 7.8 4.0 6.1 5.4 6.6 6.3 10.0 

m_13fl 0.1 0.5 0.2 0.5 0.3 0.4 0.0 0.9 4.3 7.2 4.0 5.7 7.0 6.8 7.1 9.3 

m_4pyr 0.7 2.1 0.7 1.8 0.8 2.3 0.6 1.3 9.2 14.4 8.1 12.7 9.8 12.9 13.7 22.7 

cmpyfl 0.1 0.6 0.1 0.4 0.1 0.4 0.1 0.9 0.0 0.0 0.1 0.0 0.1 0.0 0.0 0.0 

dmpyfl 0.6 0.9 0.5 1.1 1.0 1.2 0.5 1.2 10.7 13.2 10.0 12.7 12.1 14.1 16.9 21.6 

m_1pyr 0.2 1.3 0.2 0.7 0.2 1.1 0.2 1.0 4.6 9.9 4.4 8.9 5.5 8.3 7.9 16.7 

bntiop 0.1 0.2 0.1 0.1 0.0 0.2 0.2 0.4 0.7 1.1 0.5 0.8 0.5 0.9 0.7 1.2 

bzcphen 0.1 0.5 0.1 0.4 0.2 0.6 0.1 1.1 3.4 5.5 2.8 4.2 3.2 3.8 4.1 8.1 

bghifl 0.7 11.4 1.2 9.4 2.7 15.2 3.0 21.8 43.0 69.0 37.8 55.1 42.7 41.1 58.4 106.7 

phant9 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.2 

cp_cdpyr 0.0 0.7 0.0 0.6 0.0 1.8 0.0 0.9 6.2 8.1 5.7 8.3 7.2 7.1 11.2 15.6 

baanth 0.0 1.7 0.0 1.8 0.1 3.0 0.1 3.6 4.3 10.6 3.9 8.7 4.2 5.5 5.4 14.0 
124 

TABLE 54 (CONT'D). AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE EXHAUST POLYCYCLIC AROMATIC 

HYDROCARBONS, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test Number

MD-NEF-D-72MD-NEF-D-20

MD-NEF-B20-

72

MD-NEF-B20-

20

MD-NEA-D-72MD-NEA-D-20

MD-NEA-B-20-

72

MD-NEA-B-20-

20

MD-HEF-D-72MD-HEF-D-20

MD-HEF-B20-

72

MD-HEF-B20-

20a

MD-HEA-D-72MD-HEA-D-20

MD-HEA-B20-

72

MD-HEA-B20-

20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High 

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20

Temp, °F 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Media F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD 

TB Correction Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

chr_tr 0.4 3.7 0.2 2.8 0.5 4.3 0.1 5.5 14.6 32.1 13.6 24.8 14.2 17.3 18.0 41.5

bzanthr 0.8 3.6 0.2 2.4 0.7 3.6 1.1 5.5 8.9 15.6 8.8 13.7 9.2 9.4 10.4 20.3 

baa7_12 0.1 0.2 0.0 0.1 0.1 0.2 0.2 1.4 0.8 2.1 0.8 1.4 1.0 1.0 0.5 1.7 

m_3chr 0.0 0.0 0.0 0.1 0.0 0.0 0.1 0.1 0.7 5.9 1.1 1.8 0.6 1.1 1.5 2.5

chry56m 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.0 0.1 0.4 0.2 0.3 0.2 0.3 0.3 0.4

m_7baa 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.0 0.1 

dmban712 0.0 0.4 0.2 0.0 0.0 0.0 0.0 0.0 1.5 1.9 1.5 1.7 1.6 1.4 1.3 1.7 

bbjkfl 0.0 1.3 0.0 0.9 0.0 1.6 0.1 2.1 3.4 12.4 4.4 14.2 4.9 6.6 5.9 18.1

bafl 0.0 0.2 0.0 0.1 0.0 0.2 0.0 0.2 0.8 2.3 1.0 2.7 1.2 1.5 1.4 3.7

bepyrn 0.2 2.5 0.1 2.2 0.3 3.1 0.1 3.8 2.7 8.0 3.4 8.9 4.1 4.6 4.5 11.5 

bapyrn 0.0 2.3 0.1 1.8 0.1 3.4 0.0 4.3 1.6 5.4 1.9 7.1 2.3 3.0 2.6 7.9 

peryle 0.0 0.2 0.0 0.2 0.0 0.2 0.0 0.2 0.7 1.0 0.7 1.4 0.6 0.8 0.7 1.6

m_7bpy 0.1 0.0 0.1 0.1 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.2 0.0 0.0

bpy910dih 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 

incdfl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.3 

dbahacr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.3 0.0 0.1 0.1 0.2 0.0

dbajacr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.1 0.6 0.0 0.4 0.1 0.1

in123pyr 0.0 1.6 0.0 0.6 0.0 1.8 0.0 3.3 0.2 0.9 0.2 1.7 0.3 0.6 0.4 1.8 

dbahacan 0.0 0.2 0.0 0.1 0.0 0.0 0.0 0.2 0.1 0.1 0.0 0.0 0.0 0.2 0.4 0.3 

dbajan 0.0 0.3 0.0 0.0 0.0 0.0 0.0 0.1 0.2 0.5 0.2 0.8 0.2 0.5 0.3 0.7

bbchr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.2 0.0 0.0 0.0 0.1

pic 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 

bghipe 0.0 4.2 0.0 2.4 0.0 3.6 0.1 7.1 0.8 3.5 0.9 6.7 1.4 2.4 2.0 7.2 

anthan 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.2 0.1 0.2 0.1 0.1
125 

TABLE 54 (CONT'D). AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE EXHAUST POLYCYCLIC AROMATIC 

HYDROCARBONS, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test Number

MD-NEF-D-72MD-NEF-D-20

MD-NEF-B20-

72

MD-NEF-B20-

20

MD-NEA-D-72MD-NEA-D-20

MD-NEA-B-20-

72

MD-NEA-B-20-

20

MD-HEF-D-72MD-HEF-D-20

MD-HEF-B20-

72

MD-HEF-B20-

20a

MD-HEA-D-72MD-HEA-D-20

MD-HEA-B20-

72

MD-HEA-B20-

20

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High 

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20

Temp, °F 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Media F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD 

TB Correction Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

dbalpyr 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.2 0.0 0.0

corone 0.0 0.5 0.1 0.1 0.0 0.4 0.0 1.0 0.1 0.4 0.1 0.9 0.3 0.3 0.3 1.2 

dbaepyr 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.0 0.0 0.0 

dbaipyr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0

dbahpyr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.0

dbbkfl 0.0 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.1 0.0 0.1 0.0 0.0 0.0 

dbth 0.1 0.0 0.0 0.0 0.1 0.1 0.0 0.0 3.1 3.2 2.8 5.7 2.9 4.7 3.0 4.2 

dbcgcar 0.2 0.0 0.0 0.0 0.5 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

a

 The PM sample for MD-HE-F-B20-20-2 test was lost. This data is from test number MD-HE-F-B20-20-1
126 

TABLE 55. MEDIUM-DUTY VEHICLE POLYCYCLIC AROMATIC HYDROCARBONS IN 

LUBRICANTS AND FUEL

(No Statistical Analyses Were Performed On These Data)

Lubricants, μg/gram Fuels, μg/gram

TEST NUMBER

MD-NEF-D MD-NEF-B20 MD-NEA-D MD-NEA-B20 MD-HEF-D MD-HEF-B20 MD-HEA-D MD-HEA-B20 EM-6952-

F 

EM-7002-

F 

Emitter Normal Normal Normal Normal High High High High NE & HE NE & HE

Oil Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A 

Fuel Diesel B20 Diesel B20 Diesel B20 Diesel B20 Diesel B20 

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Media Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel

naphth 14.6 3.0 10.2 15.3 5.6 6.8 5.1 6.1 239.2 219.5

quinoline NR NR NR NR NR NR NR NR NR NR

mnaph2 14.0 7.0 11.4 15.6 9.4 5.7 4.5 3.9 756.6 587.2

mnaph1 4.1 0.8 4.9 6.2 3.2 2.8 1.6 0.0 402.6 292.5 

biphen 0.2 0.3 0.2 0.0 0.3 0.0 0.0 0.2 157.5 124.0

m_2bph 0.0 0.4 0.0 0.0 0.4 0.3 0.0 0.0 192.9 155.7

dmn267 5.5 1.6 4.7 2.7 4.3 0.3 1.2 0.1 1024.5 706.5

dm1367 12.2 7.4 12.5 5.6 11.4 2.9 3.1 2.8 2212.6 1469.9 

d14523 1.5 0.5 0.9 1.1 1.4 0.4 0.7 0.3 662.3 445.1

enap12 0.8 0.2 1.1 0.4 1.5 0.0 0.2 0.0 172.4 139.5

acnapy 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.1

dmn12 0.0 0.0 0.2 0.0 0.0 0.0 0.1 0.0 188.2 135.6 

dmn18 0.0 0.0 0.3 0.1 0.2 0.8 0.2 0.0 0.0 0.0

acnape 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 14.7 13.8

m_3bph 0.5 1.1 1.9 0.0 1.9 0.0 0.0 0.0 330.8 266.8

m_4bph 0.0 0.2 0.7 0.0 0.5 0.0 0.1 0.0 179.2 132.5 

dbzfur 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 6.3 3.4

em_12n 0.0 0.2 0.3 0.4 0.5 0.1 0.3 0.0 71.7 59.7

tmi235n 1.9 0.2 1.1 1.3 3.4 0.4 0.7 1.8 394.4 328.9

btmnap 4.6 1.5 2.6 1.2 4.9 0.3 1.4 2.7 514.8 381.1 

atmnap 0.9 1.1 4.9 0.5 2.7 0.2 0.3 0.4 448.2 358.6

ctmnap 4.6 2.5 5.5 3.6 4.5 0.1 0.8 2.7 518.8 415.8

em_21n 0.2 0.0 1.2 0.0 0.2 0.0 0.0 0.1 8.1 6.4

etmnap 2.0 1.3 2.6 0.8 3.8 0.4 0.6 1.8 378.3 289.3 

tm245n 0.0 0.2 0.5 0.1 0.2 0.0 0.0 0.0 84.1 61.2

ftmnap 1.9 0.9 2.8 0.7 1.7 0.4 0.6 1.3 233.8 190.2

fluore 0.0 0.2 0.6 1.1 0.6 0.0 0.3 0.5 26.4 29.1

tm145n 0.2 0.5 1.1 0.9 0.8 0.0 0.0 0.0 205.1 50.4 

jtmnap 0.7 0.5 1.8 0.4 2.6 0.0 1.3 0.4 206.2 144.0

a_mfluo 0.0 0.3 1.8 0.0 0.6 0.3 1.0 0.6 112.7 96.3

b_mfluo 0.0 0.0 0.5 0.0 0.0 0.0 0.2 0.2 35.0 27.2

m_1fluo 0.0 0.0 0.4 0.0 0.6 0.5 0.6 1.8 95.9 83.8 

fl9one 0.0 0.1 0.2 0.2 0.1 0.0 0.3 0.2 5.2 2.0

phenan 0.2 0.2 2.4 0.8 2.5 4.7 6.9 12.5 49.5 39.6

anthra 0.0 0.3 0.1 0.2 0.5 0.3 0.5 0.7 1.8 3.2

xanone 0.0 0.0 5.0 0.0 4.9 0.4 3.0 3.4 428.0 330.3 

acquone 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

m_2phen 0.5 0.2 3.1 1.1 3.7 15.3 18.1 22.9 47.3 48.9

m_3phen 0.2 0.8 3.8 1.0 1.1 14.5 18.1 18.2 48.1 45.4
127 

TABLE 55 (CONT'D). MEDIUM-DUTY VEHICLE POLYCYCLIC AROMATIC 

HYDROCARBONS IN LUBRICANTS AND FUEL

(No Statistical Analyses Were Performed On These Data)

Lubricants, μg/gram Fuels, μg/gram

TEST NUMBER

MD-NEF-DMD-NEF-B20MD-NEA-DMD-NEA-B20MD-HEF-DMD-HEF-B20MD-HEA-DMD-HEA-B20EM-6952-

F

EM-7002-

F

Emitter Normal Normal Normal Normal High High High High NE & HE NE & HE

Oil Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A

Fuel Diesel B20 Diesel B20 Diesel B20 Diesel B20 Diesel B20

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Media Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel

pnapone 0.0 0.8 0.9 0.0 0.4 0.7 0.4 1.3 29.2 37.6 

m_2anth 0.2 0.2 0.4 0.3 1.7 0.7 1.3 1.1 2.6 1.0

m_45phen 0.6 0.6 0.5 0.5 0.9 1.5 1.0 2.2 0.0 1.5

m_9phen 1.0 1.5 4.5 1.3 2.4 7.4 6.0 11.6 29.4 41.9 

mpht_1 0.4 0.9 2.0 1.1 1.1 1.7 0.8 6.4 29.9 21.6 

anthron 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

m_9ant 0.9 0.3 0.5 0.2 0.4 1.2 0.4 1.2 3.4 4.3

nap2phen 0.9 1.3 0.7 0.8 0.4 1.2 0.5 0.9 2.2 4.9 

anrquone 0.0 1.3 1.1 0.7 1.5 1.8 1.1 0.0 2.8 1.3 

a_dmph 2.3 0.5 2.8 2.6 4.8 11.3 14.9 17.0 17.8 14.9

b_dmph 1.1 0.8 3.9 2.2 4.5 5.3 8.0 7.2 12.3 10.4

dm17ph 2.2 1.0 5.6 3.0 3.9 4.3 10.6 11.2 22.3 19.9 

dm36ph 0.9 0.3 4.4 3.4 1.5 5.2 3.6 12.8 13.6 11.5 

d_dmph 2.1 3.0 2.8 2.0 3.7 6.5 4.5 10.1 18.8 13.9

e_dmph 1.4 0.5 3.8 1.5 5.3 2.4 5.2 8.3 13.5 6.6

c_dmph 4.0 1.7 10.5 4.7 8.5 18.6 28.3 28.7 49.4 37.1 

fluora 1.0 1.2 2.2 0.7 0.8 1.6 0.9 0.6 1.7 1.3 

pyrene 1.7 0.7 5.5 7.5 6.2 21.1 25.0 29.6 14.3 9.1

antal9 6.8 3.4 6.8 5.9 5.5 7.4 2.7 7.4 0.0 1.9

retene 0.5 0.5 0.7 0.3 0.4 0.3 0.4 0.4 0.3 0.0 

bafluo 1.3 0.7 1.0 1.9 0.9 3.9 4.6 4.0 1.8 0.3 

bbfluo 2.0 0.8 1.3 1.3 1.4 8.8 2.1 5.9 0.3 0.5

bmpyfl 1.5 1.3 1.9 3.5 2.3 4.9 3.9 2.9 1.3 0.5

c1mflpy 1.3 0.6 1.6 2.0 1.7 0.9 1.1 2.9 0.0 0.8 

m_13fl 1.7 1.8 2.0 4.0 2.3 2.9 4.3 4.0 1.3 0.5 

m_4pyr 3.3 3.8 6.8 5.5 1.9 8.1 12.0 7.2 11.1 6.8

cmpyfl 3.6 1.5 2.4 3.8 2.6 16.2 10.2 10.9 0.6 0.8

dmpyfl 4.5 1.0 1.6 4.0 1.0 33.2 5.9 10.3 6.8 0.4 

m_1pyr 1.0 2.1 3.5 5.6 2.7 2.7 7.0 17.8 3.7 4.4 

bntiop 0.0 2.6 2.1 1.8 2.7 5.5 2.5 0.0 0.0 0.2

bzcphen 0.0 0.8 1.8 0.8 1.7 1.1 1.5 0.0 0.2 0.1

bghifl 0.0 0.2 0.7 1.7 1.0 0.9 0.5 1.0 1.0 0.0 

phant9 0.0 0.1 0.2 0.4 0.4 0.3 0.1 0.0 0.2 0.0 

cp_cdpyr 0.0 0.2 0.2 0.4 0.2 0.3 0.3 0.0 0.1 0.0

baanth 0.0 0.4 0.1 0.6 0.2 1.0 1.2 0.0 0.0 0.1

chr_tr 0.0 1.5 0.8 2.8 2.1 2.9 5.6 5.3 0.0 0.0 

bzanthr 0.0 3.6 3.2 3.4 3.5 3.0 1.9 0.0 0.0 0.2 

baa7_12 0.0 3.6 0.0 10.5 11.0 10.2 7.3 0.0 0.0 0.0

m_3chr 1.4 1.1 0.8 0.5 1.3 2.7 3.2 0.0 0.0 0.0

chry56m 0.0 0.6 0.0 1.3 0.5 3.3 3.2 0.0 0.4 0.0 

m_7baa 0.0 0.8 0.0 0.3 0.6 0.3 0.4 0.0 0.0 0.0 
128 

TABLE 55 (CONT'D). MEDIUM-DUTY VEHICLE POLYCYCLIC AROMATIC 

HYDROCARBONS IN LUBRICANTS AND FUEL

(No Statistical Analyses Were Performed On These Data)

Lubricants, μg/gram Fuels, μg/gram

TEST NUMBER

MD-NEF-D MD-NEF-B20 MD-NEA-D MD-NEA-B20 MD-HEF-D MD-HEF-B20 MD-HEA-D MD-HEA-B20 EM-6952-

F 

EM-7002-

F 

Emitter Normal Normal Normal Normal High High High High NE & HE NE & HE

Oil Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A 

Fuel Diesel B20 Diesel B20 Diesel B20 Diesel B20 Diesel B20 

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Media Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel

dmban712 0.0 0.1 0.1 0.1 0.3 0.2 0.4 0.0 0.3 0.0

bbjkfl 0.0 0.5 0.5 0.6 0.3 0.7 0.2 0.0 0.1 0.0

bafl 0.0 0.0 0.2 0.2 0.2 0.2 0.1 0.0 0.0 0.0

bepyrn 0.3 0.6 0.2 0.5 0.5 0.2 0.5 0.0 0.0 0.0 

bapyrn 0.0 0.4 1.1 0.7 0.5 0.7 0.8 0.0 0.0 0.0

peryle 0.0 1.3 1.0 1.3 0.6 0.6 0.8 0.0 0.0 0.0

m_7bpy 0.0 1.3 0.7 1.1 0.4 0.6 0.8 0.0 0.0 0.0

bpy910dih 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 

incdfl 0.0 0.9 1.5 0.0 1.2 0.9 0.6 0.0 0.0 0.0

dbahacr 0.0 0.8 0.0 2.2 0.5 0.9 0.2 0.0 0.0 0.0

dbajacr 0.0 0.8 0.5 3.4 0.7 0.8 0.7 0.0 0.0 0.0

in123pyr 0.0 1.1 1.0 1.5 2.1 1.5 1.7 0.0 0.0 0.0 

dbahacan 0.0 1.1 1.3 2.5 3.2 1.5 0.9 0.0 0.0 0.0

dbajan 0.0 1.3 1.4 1.8 0.4 0.5 1.4 0.0 0.0 0.0

bbchr 1.2 1.0 1.2 1.5 1.5 1.0 0.8 0.0 0.0 0.0

pic 0.0 1.2 1.4 0.0 3.1 1.0 1.3 0.0 0.0 0.0 

bghipe 1.6 1.3 2.1 2.3 2.3 2.4 2.0 0.0 0.0 0.0

anthan 0.0 0.0 1.0 0.0 1.7 0.0 1.4 0.0 0.0 0.0

dbalpyr 0.0 0.0 3.8 0.0 4.8 0.0 1.7 1.5 0.0 0.0

corone 0.0 0.0 0.9 0.0 0.0 0.0 0.8 0.0 0.0 0.0 

dbaepyr 0.0 0.0 1.6 0.0 0.0 0.0 3.6 0.0 0.0 0.0

dbaipyr 0.0 0.0 0.0 0.0 0.0 0.0 1.1 1.5 0.0 0.0

dbahpyr 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

dbbkfl 0.0 0.0 1.4 0.0 0.0 0.0 3.6 0.0 0.0 0.0 

dbth 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 3.6 3.2

dbcgcar 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

mchol3 0.0 1.0 0.0 1.3 0.6 0.4 1.3 0.0 0.0 0.0
129 

TABLE 56. MEDIUM-DUTY VEHICLE AVERAGE ALKANES IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

TEST 

NUMBER 

MD-NE-FD-72-1 MD-NEF-D-20-1 

MD-NEF-B20-

72-1 

MD-NEF-B20-

20-1 

MD-NEA-D-72-1 MD-NEA-D-20-2 

MD-NEA-B-20-

72-3 

MD-NEA-B-20-

20-2 

MD-HEF-D-72-

2RR 

MD-HEF-D-20-1 

MD-HEF-B20-

72-3 

MD-HEF-B20-

20a

MD-HEA-D-72-1 MD-HEA-D-20-1 

MD-HEA-B20-

72-1 

MD-HEA-B20-

20-1 

Source Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 

Temp 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Media F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD

TB Correction Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

dodec 1050.6 1620.8 875.6 743.6 807.7 1155.5 295.5 385.0 0.2 484.1 0.7 1179.8 1.2 399.8 1.2 348.7

norfarn 533.7 781.2 542.5 446.2 547.9 693.2 242.0 266.1 103.9 637.0 83.1 1058.4 71.1 480.7 78.7 491.1

tridec 1533.0 2503.3 1407.5 1331.9 1356.4 1920.1 564.2 722.8 237.9 1468.4 184.2 2683.2 192.1 1185.0 237.6 1314.7

hpycyhx 74.3 177.5 125.3 104.7 141.4 196.4 58.9 71.7 29.8 187.6 20.5 297.8 21.8 148.1 25.3 133.5

farnes 390.5 640.0 335.5 277.5 333.7 433.9 131.1 181.8 50.8 329.8 59.6 654.0 67.7 287.9 76.7 299.7 

tdec 1241.3 2109.5 1413.3 1282.7 1354.2 1946.3 588.9 818.7 126.5 1256.5 97.8 2911.6 122.8 1264.3 161.4 1167.6

ocycyhx 57.5 135.4 96.6 102.3 120.5 127.4 58.1 64.3 14.4 80.2 11.6 186.8 10.2 81.5 9.6 81.7

pentad 1152.4 1963.0 1183.2 1136.9 1095.1 1673.4 493.7 740.7 229.4 1333.1 188.0 2793.6 217.4 1357.5 290.8 1243.1

noycyhx 85.7 151.9 91.2 81.3 100.8 101.0 36.6 56.0 18.9 97.3 11.5 150.5 16.5 95.5 24.0 95.9 

hexad 716.8 1419.6 756.7 702.9 638.7 1106.9 229.7 399.4 212.6 984.6 157.6 2079.7 211.6 918.5 279.3 927.0

norprst 347.2 601.1 324.8 253.6 305.1 428.2 78.7 135.7 109.4 446.2 87.2 922.3 80.4 443.7 134.9 446.0

decyhx 31.7 67.4 34.8 25.7 35.6 49.0 13.3 17.0 16.6 60.4 11.2 121.4 15.6 66.4 21.3 62.4

heptad 503.2 1077.9 496.0 448.1 360.2 751.8 116.8 158.6 182.6 1006.6 145.9 2156.0 186.8 1166.5 328.6 1054.3 

heptdpris 299.6 523.0 177.3 137.4 162.0 267.6 29.9 22.1 55.6 237.3 45.4 558.3 57.6 331.9 85.1 269.5

dec1yhx 18.2 45.8 20.0 16.9 16.4 32.3 4.1 2.0 23.8 43.6 17.9 70.4 5.9 14.8 9.5 37.4

octad 152.3 501.7 183.4 299.8 98.4 348.5 43.0 117.7 147.9 554.4 124.0 1260.7 159.5 590.7 268.8 649.2

phytan 102.2 249.6 94.2 137.8 90.6 172.7 22.2 56.4 72.0 223.7 53.9 423.1 60.5 218.9 107.0 249.6 

dec2yhx 6.4 15.3 12.9 12.9 9.6 11.7 1.7 2.4 11.8 28.4 7.0 56.6 9.4 21.4 5.4 38.8

nonad 97.3 388.3 141.0 333.0 85.8 279.4 90.5 249.8 219.5 509.3 161.1 1009.2 162.7 409.8 201.3 546.1

dec3yhx 7.5 22.5 10.3 16.2 6.4 10.6 4.8 7.5 7.0 7.9 3.7 30.0 7.3 9.1 2.9 9.9

eicosa 101.4 295.7 128.6 298.2 104.9 241.4 128.7 266.6 248.4 518.0 224.6 899.6 236.1 408.3 241.1 560.1 

dec4yhx 5.2 12.4 5.4 5.1 2.6 6.0 2.4 3.5 13.8 12.1 8.6 16.5 5.1 7.4 6.8 10.3

heneic 104.1 233.1 56.3 14.4 80.2 154.4 43.5 20.0 166.7 397.4 167.0 51.8 168.1 300.9 157.4 36.9

dec5yhx 3.9 12.5 3.2 14.8 4.7 7.0 3.4 6.8 14.5 26.5 10.5 27.7 12.7 17.3 18.4 20.9

docosa 56.3 123.2 50.0 116.6 48.0 86.4 45.9 105.3 91.5 196.0 101.0 350.8 107.2 181.2 114.8 247.9 
130 

TABLE 56 (CONT'D). MEDIUM-DUTY VEHICLE AVERAGE ALKANES IN EXHAUST, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test Number

MD-NE-FD-72-1MD-NEF-D-20-1

MD-NEF-B20-

72-1

MD-NEF-B20-

20-1

MD-NEA-D-72-1MD-NEA-D-20-2

MD-NEA-B-20-

72-3

MD-NEA-B-20-

20-2

MD-HEF-D-72-

2RR

MD-HEF-D-20-1

MD-HEF-B20-

72-3

MD-HEF-B20-

20a

MD-HEA-D-72-1MD-HEA-D-20-1

MD-HEA-B20-

72-1

MD-HEA-B20-

20-1

Source Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust Exhaust

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20

Temp 72 20 72 20 72 20 72 20 72 20 72 20 72 20 72 20

Media F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD

TB Correction Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

dec6yhx 1.5 1.6 0.8 2.8 2.0 1.6 2.9 2.0 6.9 6.8 10.6 13.9 8.6 8.9 9.5 9.9

tricosa 8.7 46.2 8.1 50.9 9.7 36.7 18.6 42.5 103.6 167.7 86.0 155.3 107.8 156.4 106.2 189.5

dec7yhx 2.5 5.2 0.4 3.5 1.2 3.9 0.8 3.7 8.8 9.0 5.5 5.7 6.7 6.6 13.2 10.8 

tetcos 0.0 0.0 0.0 9.2 0.0 0.0 0.0 4.1 87.7 116.1 43.3 26.2 96.9 111.5 101.3 135.8

dec8yhx 2.2 0.4 0.1 7.0 0.3 1.5 0.9 1.1 3.9 1.5 3.8 5.4 3.0 5.2 2.4 2.9

pencos 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 21.9 30.4 18.2 31.0 36.6 59.3 46.2 81.9

hexcos 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 21.8 35.1 37.7 71.4 21.7 49.8 31.3 57.1

dec9yhx 0.0 0.0 0.0 0.1 0.0 0.0 3.1 0.0 2.2 1.9 3.0 4.6 2.9 2.5 2.5 8.6

hepcos 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 14.4 15.2 28.3 30.8 12.0 19.1 15.1 12.8

cyhxeic 0.0 1.4 0.7 0.7 0.4 1.3 0.9 0.5 2.0 3.6 1.7 5.9 1.3 4.0 3.5 2.2 

octcos 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 14.9 14.4 9.6 17.6 8.3 15.7 11.0 2.6

noncos 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 8.6 6.3 13.0 17.2 9.3 10.3 9.0 7.7

cyhxhen 0.5 1.4 1.5 1.6 0.6 1.3 0.0 0.5 5.2 9.6 11.8 16.7 4.7 7.1 5.3 7.9 

tricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.9 6.8 6.0 5.2 6.5 6.0 2.5 4.2

htricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 5.1 7.2 4.5 7.9 1.9 9.6 2.8 1.3

dtricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.3 6.2 4.6 2.9 5.6 1.9 1.3 0.7

ttricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.4 6.5 2.2 2.7 0.7 0.0 0.0 0.7

tetricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.4 7.4 3.0 2.7 2.6 0.7 0.6 0.4

ptricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.4 2.2 2.0 1.6 1.9 0.2 0.4 2.5

hxtricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.8 2.9 0.6 0.4 1.6 0.5 1.5 1.0 

hptricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.8 1.8 0.4 0.5 0.6 0.2 0.7 0.5

otricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.9 3.2 1.6 1.2 2.4 0.4 0.3 0.4

ntricont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.4 1.1 2.8 0.8 1.4 0.2 0.4 0.3 

tecont 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.4 0.6 0.8 0.1 0.2 0.4 0.3

hxtric74 7.3 10.8 3.5 8.3 4.6 12.9 3.3 9.4 58.7 70.1 59.6 61.3 56.2 64.9 54.3 67.5

UCM 16758 32203 23052 25553 17221 23823 17520 12166 333051 1088650 272468 2126333 263915 1087734 342813 1107495

MD-HE-F-B20-20-2 sample was lost. The results from MD-HE-F-B20-20-1 are presented.
131 

TABLE 57. MEDIUM-DUTY VEHICLE ALKANES IN FUELS AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

SAMPLE ID

MD-NE-FDMD-NE-FB20MD-NE-AD

MD-NE-AB20

MD-HE-FD-72

MD-HE-FB20MD-HE-ADMD-HE-AB20EM-6952-

F

EM-7002-

F

Source Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel

Emitter Normal Normal Normal Normal High High High High NE & HE NE & HE

Oil Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A

Fuel Diesel B20 Diesel B20 Diesel B20 Diesel B20 Diesel B20

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Tracer Yes Yes Yes Yes Yes Yes Yes Yes No No

dodec 34 27 23 1 20 0 1 0 3681 2909

norfarn 0 52 0 0 51 7 17 0 1642 1235

tridec 75 69 58 2 63 0 1 0 4638 3523

hpycyhx 2 3 4 0 5 0 0 0 352 290

farnes 31 25 21 1 35 0 0 0 4143 3685

tdec 221 183 133 28 213 9 17 12 17626 13699

ocycyhx 17 10 10 2 16 0 1 0 1195 870

pentad 212 186 174 87 245 6 55 48 15372 12226

noycyhx 13 18 15 6 18 0 5 2 903 678

hexad 172 162 171 169 271 35 99 124 12027 9493

norprst 73 39 69 60 153 13 57 37 4503 3644

decyhx 17 17 9 10 14 2 11 7 607 506

heptad 266 207 244 433 415 41 210 228 12689 9161

heptdpris 67 29 56 104 94 13 59 72 3295 7441

dec1yhx 19 7 11 14 20 2 22 14 459 375

octad 266 224 421 388 524 144 285 362 7064 6600

phytan 92 82 151 108 174 52 97 128 2633 2531

dec2yhx 6 21 24 28 42 40 20 17 318 277

nonad 312 254 428 353 503 213 355 411 6334 5305

dec3yhx 15 13 15 32 39 21 8 32 143 109

eicosa 500 357 534 452 605 352 449 487 4594 3861

dec4yhx 64 79 9 37 116 40 46 97 95 70

heneic 689 528 678 508 790 557 567 599 3417 39

dec5yhx 136 88 107 84 56 87 105 106 62 38

docosa 490 441 422 234 515 365 414 392 1437 1106

dec6yhx 59 185 107 85 114 288 147 116 20 19

tricosa 744 667 641 292 860 686 705 607 1124 811

dec7yhx 148 124 136 132 122 113 116 118 9 15

tetcos 430 379 563 371 634 374 545 527 570 461

dec8yhx 144 89 106 39 47 45 100 37 5 4

pencos 365 324 389 378 403 372 459 359 271 223

hexcos 381 380 421 376 302 448 498 189 133 96

dec9yhx 0 10 29 20 21 158 89 33 23 2

hepcos 292 339 377 337 524 159 400 91 55 37

cyhxeic 22 91 17 41 63 57 104 57 3 0

octcos 169 132 133 528 161 176 187 169 22 19

noncos 134 102 168 215 87 242 172 44 7 7

cyhxhen 59 21 29 36 5 48 36 11 8 12

tricont 121 140 90 132 71 82 121 39 2 2

htricont 74 63 65 35 63 6 102 50 1 1

dtricont 31 45 16 31 20 10 1 38 0 0

ttricont 12 6 10 20 22 17 11 5 1 0

tetricont 8 5 5 11 2 15 10 5 0 0

ptricont 3 5 6 12 3 6 1 4 0 0

hxtricont 2 3 4 19 4 3 1 1 0 0

hptricont 5 3 2 5 3 2 2 3 0 0

otricont 3 4 2 3 1 2 3 2 0 0

ntricont 3 12 5 11 3 3 1 4 0 0

tecont 4 4 2 10 2 2 4 1 0 0

hxtric74 231 216 194 5 224 216 200 191 0 0

UCM 240702 257896 230645 215598 270533 239821 229779 214785 307094 318303

ALKANES CONCENTRATIONS, μg/gram
132 

TABLE 58. AVERAGE RESULTS OF MEDIUM-DUTY VEHICLE EXHAUST HOPANES AND STERANES, μg/mi

(No Statistical Analyses Were Performed On These Data)

Test

Number

MD-NEF-D-72 MD-NEF-D-20 MD-NEF-B20-72 MD-NEF-B20-20MD-NEA-D-72 MD-NEA-D-20 

MD-NEA-B-20-

72 

MD-NEA-B-20-

20 

MD-HEF-D-72 MD-HEF-D-20 MD-HEF-B20-72

MD-HEF-B20-

20a

MD-HEA-D-72 MD-HEA-D-20 MD-HEA-B20-72

MD-HEA-B20-

20 

Emitter Normal Normal Normal Normal Normal Normal Normal Normal High High High High High High High High

Oil Fresh Fresh Fresh Fresh Aged Aged Aged Aged Fresh Fresh Fresh Fresh Aged Aged Aged Aged

Fuel Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20 Diesel Diesel B20 B20

Temp 72.000 20.000 72.000 20.000 72.000 20.000 72.000 20.000 72.000 20.000 72.000 20.000 72.000 20.000 72.000 20.000

Media F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD F+XAD

TB 

Correction Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

hop15 0.403 0.619 0.394 0.747 0.506 0.850 0.470 0.873 1.463 1.331 1.557 1.060 1.805 2.065 2.067 2.340

hop17 0.541 1.062 0.716 0.991 0.526 1.028 0.598 1.225 4.336 4.144 4.454 3.421 4.732 5.675 5.104 5.394 

hop19 0.466 0.992 0.594 0.917 0.176 0.645 0.148 0.946 4.440 4.758 5.106 3.888 3.964 4.877 5.016 5.118 

hop20 0.163 0.305 0.206 0.206 0.159 0.375 0.129 0.329 0.141 0.214 0.215 0.081 0.037 0.210 0.251 0.165 

hop21 0.523 0.964 0.716 0.937 0.393 0.620 0.426 1.040 2.185 2.246 2.294 1.974 1.864 2.291 2.084 2.283 

hop22 0.440 0.779 0.554 0.673 0.259 0.423 0.269 0.603 1.929 1.846 1.821 1.576 1.486 1.695 1.958 1.713

hop23 0.112 0.112 0.112 0.193 0.108 0.000 0.000 0.000 0.022 0.032 0.000 0.000 0.138 0.000 0.013 0.089

hop24 0.145 0.294 0.115 0.119 0.000 0.000 0.000 0.129 1.143 1.160 1.289 1.070 0.922 1.080 1.172 1.368

hop25 0.413 0.599 0.595 0.505 0.218 0.240 0.214 0.423 0.983 1.012 1.172 1.104 0.979 1.098 3.782 2.154

hop26 0.426 0.563 0.425 0.427 0.071 0.256 0.076 0.359 0.734 0.732 0.718 0.606 0.545 0.653 0.989 1.127

hop27 0.008 0.035 0.003 0.000 0.000 0.000 0.000 0.000 0.521 0.607 0.518 0.406 0.340 0.393 0.452 0.503

ster42 0.322 0.510 0.354 0.425 0.329 0.568 0.440 0.635 0.898 0.778 0.864 0.665 1.006 1.018 0.825 0.912 

ster43 0.388 0.934 0.386 0.806 0.204 0.779 0.359 1.015 2.275 2.231 2.268 2.093 2.373 2.425 2.308 2.572 

ster44 0.471 0.817 0.495 0.794 0.517 0.834 0.600 1.061 1.284 1.160 1.317 1.216 1.243 1.320 0.967 1.194 

ster45_40 0.555 0.255 0.445 0.722 0.450 0.594 0.593 1.193 3.373 3.283 3.102 3.064 3.814 2.799 3.157 3.239 

ster46 0.250 0.383 0.379 0.450 0.243 0.358 0.260 0.488 0.664 0.696 0.615 0.548 0.664 0.800 0.705 0.716

ster47 0.232 0.406 0.314 0.493 0.245 0.467 0.242 0.480 1.064 1.049 1.013 1.136 1.194 0.967 0.807 0.951

ster48_41 0.162 0.295 0.146 0.205 0.120 0.129 0.117 0.265 1.543 1.445 1.482 1.227 1.201 0.858 1.334 1.371

ster49 0.054 0.151 0.166 0.202 0.084 0.135 0.039 0.113 0.665 0.619 0.584 0.665 0.716 0.902 0.650 0.851

ster50 0.415 0.639 0.422 0.563 0.241 0.661 0.443 0.597 0.273 0.197 0.236 0.160 0.250 0.258 0.205 0.257

ster51 0.421 0.865 0.532 0.650 0.238 0.490 0.321 0.653 1.233 1.252 1.447 1.043 1.060 1.234 1.129 1.101

ster52 0.409 0.717 0.485 0.658 0.271 0.458 0.295 0.717 0.638 0.652 0.657 0.567 0.662 0.814 0.671 0.707 

ster53 0.281 0.579 0.352 0.437 0.194 0.376 0.213 0.576 0.734 0.797 0.671 0.711 0.666 0.658 0.604 0.675 

a

 The PM sample for MD-HE-F-B20-20-2 test was lost. This data is from test number MD-HE-F-B20-20-1 
133 

TABLE 59. MEDIUM-DUTY VEHICLE LUBRICANTS AND FUELS HOPANES AND 

STERANES 

(No Statistical Analyses Were Performed On These Data)

Lubricants, μg/gram Fuels, μg/gram

TEST 

NUMBER

MD-NEF-DMD-NEF-B20MD-NEA-DMD-NEA-B20MD-HEF-DMD-HEF-B20MD-HEA-DMD-HEA-B20 EM-6952-F EM-7002-F

Emitter Normal Normal Normal Normal High High High High NE & HE NE & HE

Oil Fresh Fresh Aged Aged Fresh Fresh Aged Aged F&A F&A

Fuel Diesel B20 Diesel B20 Diesel B20 Diesel B20 Diesel B20

Temp 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20 72 & 20

Media Oil Oil Oil Oil Oil Oil Oil Oil Fuel Fuel

hop15 13.71 42.38 13.21 34.43 37.79 43.66 32.13 38.14 0.14 0.19

hop17 40.20 44.26 35.79 280.19 40.46 30.50 29.86 45.73 0.40 0.47 

hop19 40.73 31.64 26.61 148.09 33.26 23.58 26.53 32.98 0.18 0.23

hop20 0.00 0.00 0.00 23.63 0.00 0.00 0.00 0.98 0.00 0.00 

hop21 26.09 22.90 15.66 114.14 16.21 16.73 15.54 21.47 0.08 0.13

hop22 21.65 19.64 12.30 93.35 10.61 10.47 11.23 20.28 0.05 0.10 

hop23 7.08 6.00 3.94 33.49 2.66 2.57 3.36 6.98 0.00 0.00

hop24 15.13 11.40 8.00 60.35 9.02 7.99 5.77 9.11 0.00 0.10 

hop25 20.88 6.50 8.91 44.09 5.73 6.07 5.07 10.01 0.00 0.10

hop26 11.34 8.70 4.74 39.22 5.83 4.10 3.86 8.78 0.00 0.00 

hop27 5.91 4.67 3.67 27.39 2.73 2.83 2.35 3.11 0.00 0.00

ster42 8.03 8.87 6.49 13.25 17.53 6.37 8.53 11.05 0.09 0.08 

ster43 30.58 26.65 19.65 21.46 26.62 21.17 20.33 23.98 0.22 0.24

ster44 22.36 16.64 13.34 16.59 19.31 12.77 14.05 16.47 0.18 0.16 

ster45_40 40.09 25.93 23.74 26.04 30.18 23.21 21.39 23.19 0.23 0.41

ster46 9.98 7.32 6.70 9.11 8.67 5.66 6.70 8.63 0.17 0.20 

ster47 11.74 9.91 9.85 11.19 11.00 8.19 9.64 11.20 0.03 0.05

ster48_41 10.79 9.98 8.11 24.76 7.96 7.76 7.53 8.96 0.09 0.02 

ster49 14.33 5.78 8.04 5.55 5.65 4.69 4.14 5.04 0.05 0.10

ster50 4.49 2.45 2.71 4.26 3.77 2.96 2.33 4.13 0.02 0.02 

ster51 15.36 14.49 10.83 18.53 16.23 11.10 10.66 13.00 0.06 0.11

ster52 10.38 11.36 8.19 12.21 9.92 8.89 8.38 10.25 0.04 0.06 

ster53 8.25 11.06 8.60 16.86 6.59 7.98 6.97 8.71 0.02 0.23
134 

8.5.2.6 Particle-Phase Elemental and Organic Carbon 

 PM sampled from the medium-duty vehicles were also analyzed by DRI for elemental 

carbon and organic carbon (EC/OC). Table 60 shows the average results in μg/mile of the 

replicate tests performed in each configuration. The configurations are identified in the five left 

columns of the table, and EC/OC results are shown in the three right columns. In Table 60, EC 

is elemental carbon, OC is organic carbon, and TC is total carbon. 

TABLE 60. MEDIUM-DUTY VEHICLE PARTICULATE ELEMENTAL CARBON AND 

ORGANIC CARBON

(No Statistical Analyses Were Performed On These Data)

8.5.2.7 Particle-Phase Sulfates

Particles sampled from the medium-duty tests were also analyzed by DRI for sulfates. 

Table 61 shows the average results in μg/mile of the replicate tests performed in each 

configuration. 

ID Emitter Oil Fuel Temp EC OC TC

MD-NE-F-D-72 Normal Fresh Diesel 72 71.8 21.6 93.4

MD-NE-F-D-20 Normal Fresh Diesel 20 90.6 41.7 132.3

MD-NE-F-B20-72 Normal Fresh B20 72 65.4 27.9 93.3

MD-NE-F-B20-20 Normal Fresh B20 20 67.4 48.6 115.9

MD-NE-A-D-72 Normal Aged Diesel 72 76.1 24.8 100.9

MD-NE-A-D-20 Normal Aged Diesel 20 75.9 39.3 115.2

MD-NE-A-B-20-72 Normal Aged B20 72 53.6 27.9 81.4

MD-NE-A-B-20-20 Normal Aged B20 20 68.8 47.3 116.0

MD-HE-F-D-72 High Fresh Diesel 72 316.0 59.1 375.1

MD-HE-F-D-20 High Fresh Diesel 20 180.5 68.6 249.1

MD-HE-F-B20-72 High Fresh B20 72 269.7 63.0 332.7

MD-HE-F-B20-20 High Fresh B20 20 175.9 86.7 262.7

MD-HE-A-D-72 High Aged Diesel 72 332.5 61.2 393.6

MD-HE-A-D-20 High Aged Diesel 20 192.6 64.3 256.9

MD-HE-A-B20-72 High Aged B20 72 282.3 53.8 336.1

MD-HE-A-B20-20 High Aged B20 20 257.6 102.7 360.3

CARBON EMISSION RATE, mg/mile
135 

TABLE 61. AVERAGE SULFATE EMISSIONS FROM MEDIUM-DUTY VEHICLES

(No Statistical Analyses Were Performed On These Data)

8.5.2.8 Particle-Phase Soluble Organic Fraction 

 PM sampled from the medium-duty tests were also analyzed by DRI for soluble organic 

fraction (SOF). Table 62 shows the average results for the normal emitter and high emitter, in 

percent SOF, of the duplicate tests performed in each configuration. 

In all cases, operation at 20°F nominally increased SOF percentage compared to 

operation at 72°F. No trends are evident in SOF percentages when comparing the normal emitter 

to the high emitter. In all cases, operation with B20 nominally increased SOF compared to 

operation on straight diesel. With the normal emitter, operation with aged oil nominally 

increased SOF compared to fresh oil operation, but no SOF trend is evident between fresh and 

aged oil test of the high emitter.

TEST NUMBER EMITTER OIL FUEL TEMP

AVERAGE 

SULFATE 

(μg/mile)

MD-NE-F-D-72 Normal Fresh Diesel 72 402

MD-NE-F-D-20 Normal Fresh Diesel 20 1561

MD-NE-F-B20-72 Normal Fresh B20 72 124

MD-NE-F-B20-20 Normal Fresh B20 20 562

MD-NE-A-D-72 Normal Aged Diesel 72 126

MD-NE-A-D-20 Normal Aged Diesel 20 458

MD-NE-A-B-20-72 Normal Aged B20 72 67

MD-NE-A-B-20-20 Normal Aged B20 20 344

MD-HE-F-D-72 High Fresh Diesel 72 130

MD-HE-F-D-20 High Fresh Diesel 20 486

MD-HE-F-B20-72 High Fresh B20 72 195

MD-HE-F-B20-20 High Fresh B20 20 420

MD-HE-A-D-72 High Aged Diesel 72 228

MD-HE-A-D-20 High Aged Diesel 20 614

MD-HE-A-B20-72 High Aged B20 72 319

MD-HE-A-B20-20 High Aged B20 20 927
136 

TABLE 62. MEDIUM-DUTY VEHICLES AVERAGE PARTICLE-PHASE SOLUBLE 

ORGANIC FRACTION

(No Statistical Analyses Were Performed On These Data)

8.5.2.9 Particle Number and Size Distribution 

Figures 49 and 50 show the exhaust PN concentration for the medium-duty (MD) normal 

emitter (NE). The data are shown for the fresh and aged oil using B0 (TxLED) and B20 at 72°F 

and 20°F. The data are plotted as an average concentration for the cold-start (Bags 1 and 2) and 

the hot-start (Bags 3 and 4) portion of the UDC. The exhaust PN concentration ranged from 

about 10x106 part./cm3 to 20x106

 part./cm3. No major differences in PN emissions were 

observed between 72oF and 20oF or between the cold-start and the hot-start portions of the cycle. 

The B20 resulted in lower solid and volatile PN emission, compared to B0. The PN reduction 

was on the fuel order of 15 to 20 percent. The MD NE vehicle with fresh oil emitted higher 

numbers of solid and volatile particles, compared to PN emissions with the aged oil. This trend 

was observed during both the cold-start and the hot-start portions of the drive cycle. This trend 

was also consistent with what was observed with the light-duty NE. Figures 51 and 52 show the 

percent ratio of solid and volatile PN concentration to total PN concentration. Fifty to 83 percent 

of the number of particles emitted from the MD NE were solid in nature.

TEST NUMBER LUBRICANT VEHICLE FUEL AMBIENT 

TEMPERATURE, °F

AVERAGE 

SOF, %

MD-NE-F-D-72 Fresh Normal Emitter Diesel 72 19%

MD-NE-F-D-20a Fresh Normal Emitter Diesel 20 30%

MD-NE-F-B20-72 Fresh Normal Emitter B20 72 24%

MD-NE-F-B20-20 Fresh Normal Emitter B20 20 46%

MD-NE-A-D-72 Aged Normal Emitter Diesel 72 21%

MD-NE-A-D-20 Aged Normal Emitter Diesel 20 32%

MD-NE-A-B20-72 Aged Normal Emitter B20 72 27%

MD-NE-A-B20-20 Aged Normal Emitter B20 20 40%

MD-HE-F-D-72 Fresh High Emitter Diesel 72 16%

MD-HE-F-D-20 Fresh High Emitter Diesel 72 30%

MD-HE-F-B20-72 Fresh High Emitter B20 20 29%

MD-HE-F-B20-20 Fresh High Emitter B20 72 40%

MD-HE-A-D-72 Aged High Emitter Diesel 20 16%

MD-HE-A-D-20 Aged High Emitter Diesel 72 26%

MD-HE-A-B20-72 Aged High Emitter B20 20 22%

MD-HE-A-B20-20 Aged High Emitter B20 72 50% a

 MD-NE-F-D-20-2 measured more SOF mass than PM mass. Data point was deleted, and SOF from only 

MD-NE-F-D-20-1 is reported.
FIGURE 49. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION 

(MEDIUM-DUTY, NORMAL EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data) 

FIGURE 50. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION 

(MEDIUM-DUTY, NORMAL EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data) 

137 
138 

FIGURE 51. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(MEDIUM-DUTY, NORMAL EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 52. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(MEDIUM-DUTY, NORMAL EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)
139 

 Figures 53 and 54 show the exhaust PN concentration for the MD high emitter (HE). The 

exhaust PN concentration ranged from 12x106 part./cm3 to 23x106 part./cm3. This was very 

similar in range to the MD NE, but no consistent trend was observed in PN emissions between 

B0 and B20. No major differences in PN were observed between cold and normal temperature 

and cold-start and the hot-start portions of the cycle. PN emissions, particularly solid PN, were 

higher with the aged oil compared to fresh oil. This is consistent with the observation made with 

the light duty HE between aged oil and fresh oil, although the trend with the MD HE was not as 

pronounced. As shown in Figures 55 and 56, solid PN ranged from 26 to 65 percent of total PN. 

This range was lower than observed with the MD NE, suggesting more volatile PN with the MD 

HE, compared to the MD NE. 

Figure 57 through Figure 72 show the size distributions for the MD NE and HE using the 

fresh and aged oil for the B0 and B20 at 72°F and 20°F ambient temperature. The data are 

plotted as an average for the cold-start and hot-start portions of the transient cycle. For the NE 

and HE, the solid particle distributions exhibited a similar monomodal lognormal size 

distribution structure that consists of an accumulation mode with peaks between 50 nm and 

70 nm. The total particle size distribution exhibited a bimodal lognormal distribution structure 

with a volatile nuclei mode peak between 10 nm and 20 nm. A more pronounced volatile nuclei 

mode was observed at 20°F compared to 72°F, and with the HE versus the NE. For example, the 

NE had a small nuclei mode, particularly at 72°F, compared to the accumulation mode, where 

with the HE, the nuclei mode reached a peak level that is comparable with the peak of the 

accumulation mode at 72°F, and a higher peak level at 20°F. The increase in volatile nuclei 

mode particles can be indicative of increased oil consumption using similar technology vehicles 

with similar fuel and oil usage.

FIGURE 53. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(MEDIUM-DUTY, HIGH EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)
140 

FIGURE 54. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(MEDIUM-DUTY, HIGH EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 55. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(MEDIUM-DUTY, HIGH EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)
141 

FIGURE 56. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES 

(MEDIUM-DUTY, HIGH EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 57. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 72°F, MEDIUM-DUTY, 

NORMAL EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)
142 

FIGURE 58. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 72°F, MEDIUM-DUTY, 

NORMAL EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 59. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 20°F, MEDIUM-DUTY, 

NORMAL EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)
143 

FIGURE 60. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 20°F, MEDIUM-DUTY, 

NORMAL EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 61. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 72°F, MEDIUM-DUTY, 

NORMAL EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)
144 

FIGURE 62. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 72°F, MEDIUM-DUTY, 

NORMAL EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 63. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 20°F, MEDIUM-DUTY, 

NORMAL EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)
145 

FIGURE 64. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 20°F, MEDIUM-DUTY, 

NORMAL EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 65. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 72°F, MEDIUM-DUTY, 

HIGH EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)
146 

FIGURE 66. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 72°F, MEDIUM-DUTY, 

HIGH EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 67. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 20°F, MEDIUM-DUTY, 

HIGH EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)
147 

FIGURE 68. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 20°F, MEDIUM-DUTY, 

HIGH EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 69. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 72°F, MEDIUM-DUTY, 

HIGH EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)
148 

FIGURE 70. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 72°F, MEDIUM-DUTY, 

HIGH EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 71. NUMBER-WEIGHTED SIZE DISTRIBUTION (B0, 20°F, MEDIUM-DUTY, 

HIGH EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data) 
149 

FIGURE 72. NUMBER-WEIGHTED SIZE DISTRIBUTION (B20, 20°F, MEDIUM-DUTY, 

HIGH EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)

8.6 PM Apportionment

For the medium-duty vehicle evaluations, two diesel fueled vehicles were tested in 

duplicate using the Unified Driving Cycle at two test temperatures (72o and 20oF) with two test 

fuels (a diesel fuel and that same diesel fuel blended with 20 percent biodiesel) and with two 

crankcase oils (a “fresh” or previously unused oil and a similar oil that had been “aged” in 

another test program). A total of 16 tests were conducted on each of the two vehicles. One of 

the two vehicles was designated as a normal emitter (NE) and was equipped with an oxidation 

catalyst, while the second vehicle was designated as a high emitter (HE) and had no exhaust 

aftertreatment. A more complete description of the vehicles, test cycle, fuels, and lubricants is 

presented in an earlier section of this report.

In addition to analyses conducted to determine the regulated gaseous exhaust emissions 

and total PM emissions, a number of analyses were conducted to further characterize the PM. 

These analyses included XRF and ICP-MS analyses for element content (51 different elements), 

TOR analyses to determine “elemental” (EC) and “organic” (OC) carbon content, and GC-MS

analyses to determine alkanes and cycloakanes (50 compounds), hopanes and steranes (23 

compounds) and polycyclic aromatics or PAHs (55 compounds). The GC-MS analyses were 

also conducted on gas phase emissions to provide a distribution of these semi-volatile organic 

compounds (SVOCs), between the particle and gas phase of the exhaust. The GC-MS and ICPMS analyses were also conducted on the test fuels and test oils to provide potential sources and 

concentrations of compounds found in the exhaust. More specific details on these analyses are 

presented in Section 8.5 of this report. Hexatriacontane-d74 (n-C36D74) was added to both oils 
150 

utilized in this study to help in determining the impact of the crankcase oils on the PM emissions. 

Analyses for this deuterated alkane were conducted as part of the GC-MS analysis for alkanes 

and cycloalkanes. Exhaust, oil, and fuel samples were all evaluated.

The following approach was followed to determine possible origins (either fuel or 

lubricant) of exhaust PM for the two medium-duty vehicles:

• Review regulated emissions for trends

• Review chemical analyses of PM, fuel, and oil samples

• Utilize averages and sums when appropriate to minimize variability in data

• Utilize analytical results for elements to estimate an oil consumption rate for each 

vehicle 

• Review carbon analyses for “elemental” (EC) and “organic” carbon (OC) and 

compare to PM results

• Review hexane and cyclohexane results; utilize hexatriacontane-d74 results to 

estimate unburned oil contribution to PM

• Review hopane and sterane results: utilize to make a second estimate of unburned oil 

in PM

• Compare unburned oil estimates to OC 

• Investigate impact of PAH emissions rates on PM

• Summarize observations

8.6.1 Regulated Emissions and Fuel Economy 

Regulated emissions and fuel economy data from all sixteen tests conducted on each of 

the two test vehicles were averaged and are presented in Table 63 (Normal Emitter) and Table 64 

(High Emitter). To illustrate the impact of each of the test parameters on the average, a percent 

difference from the average is presented for each set of variables (temperature, fuel, and oil). 

For example, the eight tests conducted on the high emitter at 72oF had HC emissions that were 

45 percent lower than the overall average value, 0.277 g/mi, while the eight tests conducted at 

20oF were 45 percent higher than the average. When the tests were regrouped by fuel, the eight 

tests conducted with TxLED diesel fuel (B0 or “D” as shown in the following tables) had HC 

emissions six percent lower than the 0.277 g/mi average and the biodiesel blend (B20) had HC 

emissions six percent higher than the average.

TABLE 63. REGULATED EMISSIONS AND FUEL ECONOMY, NORMAL EMITTER

(No Statistical Analyses Were Performed On These Data)

Measurement Average*

Percent Difference From Average

72oF 20oF D B20

Fresh 

Oil

Aged

Oil

HC, g/mi 0.448 -14 +14 <1 <1 <1 <1

CO, g/mi 1.770 -18 +18 +3 -3 <1 <1

NOx, g/mi 5.417 -18 +18 <1 <1 +3 -3

PM, g/mi 0.120 -15 +15 +8 -8 +6 -6

FE, mpg 12.88 +3.5 -3.5 +0.1 -0.1 -2.7 +2.7

*Averages include all tests from the two test temperature x two test fuel x two test lubricant x duplicate test matrix.
151 

TABLE 64. REGULATED EMISSIONS AND FUEL ECONOMY, HIGH EMITTER

(No Statistical Analyses Were Performed On These Data)

Measurement Average*

Percent Difference From Average

72oF 20oF D B20

Fresh 

Oil

Aged

Oil

HC, g/mi 0.277 -45 +45 -6 +6 +12 -12

CO, g/mi 1.593 -20 +20 -2 -2 -3 +3

NOx, g/mi 7.127 -2 +2 -3 +3 -3 +3

PM, g/mi 0.420 +27 -27 -6 +6 -5 +5

FE, mpg 15.98 +2.8 -2.8 -0.8 +0.8 -0.5 +0.5

*Averages include all tests from the two test temperature x two test fuel x two test lubricant x duplicate test matrix.

The high emitter (HE) had higher average PM and NOx emissions than the normal emitter 

(NE), but lower average HC and CO emissions and better fuel economy. These results indicate 

that the HE had been optimized more for power and fuel economy, while the NE had been 

optimized to meet more stringent NOx and PM standards.

As can be seen in Tables 63 and 64, test temperature had a much larger impact on exhaust 

emissions and fuel economy than did fuel type or lubricant age for both medium duty vehicles. 

Of special note is the observation that PM emissions were 27 percent lower than the average for 

the HE at 20oF. This decrease in PM emissions with lower temperature was not observed for the 

NE. Nominal trends in emissions and fuel economy related to fuel type and lubricant age were 

generally much smaller than those observed for test temperature and were not nominally 

consistent for the two test vehicles.

8.6.2 Estimates for Vehicle Oil Consumption Rates 

The first step in evaluating the impact of lubricating oil on PM emissions is to determine 

the amount of lubricating oil entering the exhaust stream. Carbon compounds in lubricating oil 

can be burned in the engine or aftertreatment system to produce gas phase components, while 

other elements in the oil such as calcium or zinc are expected to be collected as PM, even if 

burned. Therefore the elements detected in the ICP-MS and XRF analyses of exhaust were 

averaged and compared to elements found in the oils. Using both the concentration of selected 

elements in the exhaust (μg/mi) and in the lubricating oil (μg/g), an oil consumption rate (g/mi) 

can be calculated. Four elements (phosphorus, zinc, calcium, and sulfur) were found at relatively 

high concentrations in both the exhaust PM samples and in the oil samples. The emission rates 

for three of these four elements (sulfur was omitted because it is present in both the fuel and the 

oil and can be burned to give a gas phase component, sulfur dioxide) were averaged for both the 

NE and the HE and the results are presented in Table 65. Also in the table are the ratios of the 

three elements in the exhaust and in the oil. The ratios were calculated by dividing the 

concentration of each element by the phosphorus concentration. These ratios show that the HE 

emission rates for phosphorus, zinc, and calcium are very similar to their proportions in the oil, 

and all three elements could be used to represent the oil consumption process equally. The 

element ratios for the NE exhaust samples are similar to those in the oil, but illustrate the loss of 

phosphorus, and to a smaller extent zinc, in the exhaust system (possibly in the oxidation 

catalyst) as compared to calcium.
152 

TABLE 65. ELEMENTS FROM OIL IN PM

(No Statistical Analyses Were Performed On These Data)

Element

Normal Emitter

Average, μg/Mi

Ratio

In Exhaust

Ratio

In Oil

P 92 1.0 1.00

Zn 152 1.6 1.25

Ca 276 3.0 2.00

Element

High Emitter

Average, μg/Mi

Ratio

In Exhaust

Ratio

In Oil

P 419 1.0 1.00

Zn 531 1.3 1.25

Ca 809 1.9 2.00

An average oil consumption rate for each of the two test vehicles was calculated by 

dividing the average concentration of an element in the exhaust (μg/mi) by the corresponding 

average concentration in the oil (μg/g). When these calculations were carried out, 0.16 quarts 

per 1000 miles or 133 mg/mi (determined from the calcium concentrations only, due to the 

potential loss of phosphorus and zinc in the exhaust system) was obtained for the NE and 0.49 

quarts per 1000 miles or 408 mg/mi (based on average results from phosphorus, zinc, and 

calcium concentrations) was determined for the HE. While no actual measured oil consumption 

rate was available for the NE, an average measured rate equivalent to the calculated rate (0.49 

quarts per 1000 miles) had been obtained for the HE over 2,311 in-use road miles preceding 

testing in this program. 

8.6.3 Wear Elements

In addition to the exhaust PM elements originating from the oil, groups of elements 

associated with engine wear were also observed in the exhaust PM samples. Five elements 

(aluminum, chromium, manganese, molybdenum, and iron) were present at higher levels in the 

NE exhaust than in the HE exhaust, while 4 elements (copper, tin, nickel, and lead) were found 

at higher levels in the HE exhaust. Average emission rates for these nine wear elements are 

presented in Table 66. The first five elements possibly originate from engine wear of aluminum 

and steel alloy components and indicate more engine wear in the NE vehicle compared to the 

HE. The remaining five elements could all originate from bearing wear, indicating a high wear 

rate in the HE. Table 67 presents the impact of the test variables on the emission rates of iron 

(both vehicles) and lead (HE only). As can be seen in the table, no single variable dominates the 

iron results for either vehicle, and the fuel type and oil age trends go in opposite directions for 

the two vehicles. However, the HE lead emissions indicate that the B20 fuel has a relatively 

large impact on bearing wear in the HE. The aged oil was also found to have a large impact and 

the combination of these two variables resulted in lead emission rates on the order of 1 mg/mi.
153 

TABLE 66. ELEMENTS FROM WEAR, μg/mi (AVERAGES FOR EACH VEHICLE)

(No Statistical Analyses Were Performed On These Data)

Element Normal Emitter High Emitter

Al 32 26

Cr 21 8

Mn 14 9

Mo 5 1

Fe 705 609

Cu 10 23

Sn 1 12

Ni 6 9

Pb 1 316

TABLE 67. TEST VARIABLE IMPACT ON SELECTED WEAR ELEMENTS

(No Statistical Analyses Were Performed On These Data)

Element 

(Vehicle) Averages

Percent Difference From Average

72oF 20oF D B20 Fresh Oil Aged Oil

Fe (NE) 705 -54 +54 -42 -42 +50 -50

Fe (HE) 609 -21 +21 -40 +40 -43 +43

Pb (HE) 316 +2 -2 -92 +92 -75 +75

8.6.4 Carbon Analyses for “Elemental” and “Organic” Content of PM 

Exhaust PM samples were analyzed by TOR for “elemental” carbon (EC) or soot 

content, “organic” carbon (OC), and total carbon (TC) content. The average results for these 

analyses, and the impact of each of the test variables on these averages is presented in Table 68. 

The PM results for each vehicle are also shown for comparison. Recall the unusual observation 

of HE PM levels decreasing with the lower test temperature (Table 64). This observation 

appears to be the direct result of a decrease in the EC emission rate, as the OC emissions increase 

as expected with decreasing temperature. All three test variables give opposing nominal total 

carbon emission results for the two test vehicles. On average, the OC was 33 percent of the total 

carbon for the NE and 22 percent for the HE. 

TABLE 68. TOTAL, “ELEMENTAL,” AND “ORGANIC” CARBON EMISSIONS

(No Statistical Analyses Were Performed On These Data)

Averages*

mg/mi

Percent Difference From Average

72oF 20oF D B20 Fresh Oil Aged Oil

Normal Emitter

EC 71.2 -6 +6 +10 -10 +4 -4

OC 34.9 -27 +27 -9 +9 <1 <1

TC 106.1 -13 +13 +4 -4 +3 -3

PM 120 -15 +15 +8 -8 +6 -6

High Emitter

EC 250.9 +20 -20 +2 -2 -6 +6

OC 69.9 -15 +15 -9 +9 <1 <1

TC 320.8 +12 -12 -1 +1 -5 +5

PM 420 +27 -27 -6 +6 -5 +5

*Averages include all tests from the two test temperature x two test fuel x two test lubricant x duplicate test matrix.
154 

An attempt was made to account for the total PM mass by combining the measured total 

carbon mass with a sum of oil and wear derived element mass (Table 69). Sulfur and 

phosphorus were assumed to be present as sulfate and phosphate and the organic carbon mass 

was assumed to have 1.5 hydrogen atoms per carbon atom. When these various masses were 

combined, the totals were found to represent 94 percent of the measured PM for the NE and 

80 percent of the measured PM for the HE.

TABLE 69. CARBON AND OTHER ELEMENT TOTALS COMPARED TO

TOTAL PM, AVERAGES, mg/mi

(No Statistical Analyses Were Performed On These Data)

Normal Emitter High Emitter

Total Carbon 106.1 320.8

Elementsa 2.4 4.7

Hydrogen Mass for OCb 4.4 8.7

Total 112.9 334.2

Measured PM 120 420 a Mass for S and P assumed to be SO4 and PO4 b Mass for 1.5 H per C assumed

8.6.5 Estimation of Unburned Oil Content in PM

The elements phosphorus, zinc, and calcium were utilized to determine an overall oil 

consumption rate for the two test vehicles, 133 mg/mi for the NE and 408 mg/mi for the HE. 

However, some or most of the organic content of the oil could be burned in the engine or, in the 

case of the NE, in the oxidation catalyst. One approach to determining how much of the organic 

material from the oil remains in the PM is to compare SVOCs in the PM to those unique to the 

oil, as was done for determining the overall oil consumption rate. This approach assumes that 

the oil either survives the combustion process intact (including all tracers) or is completely 

consumed. GC-MS analyses of the SVOC alkanes and cycloalkanes, and of the hopanes and 

steranes provided data to make these estimates.

The oil utilized in this study contained a hexatriacontane-d74 (C36D74) tracer that was 

determined to be at a 210 μg/g level in the oil (average of 7 of the oil samples utilized in this 

study). The average PM emission rate (all sixteen tests) for hexatriacontane-d74 was 7.5 μg/mi 

for the NE and 62 μg/mi for the HE. If the emission rates in μg/mi are divided by the oil 

concentration in μg/g, the result gives an estimated “unburned” oil emission rate. The calculated

average emission rate for unburned oil for the normal emitter was 36 mg/mi, while the projected 

unburned oil emission rate for the HE was 290 mg/mi. 

This approach was repeated using the sum of 11 hopanes and 12 steranes that were 

analyzed in this study. Hopanes and steranes are found in the oil and have been utilized as

markers for the presence of lubricating oil. The total average concentration of these 23 hopanes 

and steranes in the test oils was 310 μg/g. The total average PM exhaust emission rate for the 

NE was 9.8 μg/mi and the corresponding average for the HE was 33 μg/mi. Dividing the 

exhaust emission rates by the oil concentration result in estimated unburned oil emission rates of 

33 mg/mi for the NE and 107 mg/mi for the HE. It should be noted that these hopanes and 

steranes were also found in the fuels utilized in this part of the study (average of 2.5 μg/g). 
155 

While the oils contained approximately 125 times more hopanes and steranes than the fuels, the 

test vehicles consumed on average 1900 (NE) and 500 (HE) times more fuel than oil. If the 

survival rate of the fuel hopanes and steranes is not negligible, their presence will confound the 

unburned oil estimates. Table 70 presents a comparison of the calculated unburned oil estimates 

to the organic carbon (OC) component of PM as determined by TOR. 

TABLE 70. COMPARISON OF UNBURNED OIL ESTIMATES TO OC

Approach

Average Emission Rate, mg/mi

Normal Emitter High Emitter

Hexatriacontane-d74 36 290

Hopanes and Steranes 32 107

OC 35 70

There appears to be good agreement of the unburned oil estimates with the total OC for 

the NE, indicating that the OC component of the PM is primarily unburned oil and that either the 

hexatriacontane-d74 or the hopane/sterane totals can be utilized to make this prediction. There 

were high, and possibly anomalous, hopanes levels measured in the lubricants from the tests for 

MD-NE-A-B20. These data were used in the estimates shown in Table 70 for the normal 

emitter. If these data were not included in the averaged hopanes and steranes then the estimated 

unburned oil emission rates would be slightly higher and more in agreement with the OC results. 

These results also indicate that 74 percent of the oil entering the exhaust stream is burned in the 

engine or in the oxidation catalyst (calculated oil consumption rate of 133 mg/mi minus average 

unburned oil consumption rate of 34 mg/mi equals 99 mg/mi of burned oil or 74 percent of the 

total oil consumed). The NE hopane/sterane totals also vary with the test temperature (26 

percent lower than average at 72o and 26 percent higher than average at 20oF) in the same 

manner and magnitude as does the OC (Table 70). The variation with test temperature for the 

hexatriacontane-d74 exhaust PM results is slightly larger (±37 percent), but still reasonable in 

magnitude and direction of the trend. 

The unburned oil estimates using exhaust hexatriacontane-d74 and hopane/sterane 

measurements, however, do not show good agreement with the TOR OC component for the HE; 

the hexatriacontane-d74 overestimating the OC by more than three-fold, and the hopanes and 

steranes by about 50 percent. These overestimates may indicate there is possibly not enough EC 

in the exhaust to capture all of the lighter components of oil as PM. The heavier oil components, 

such as the hexatriacontane-d74 tracer are either displacing lighter components from the PM or 

are preferentially condensing into the PM, or both. 

The displacement of lighter oil components from the PM to the gas phase can be 

illustrated by the emission results for eicosane (C20H42) representing a lighter oil component, and 

hexacosane (C26H54), representing a heavier oil component (Table 71). Also, recall that the EC 

levels for the HE actually decreased with a decrease in temperature (20 percent from the 

average), while the OC levels increased (15 percent from the average). The NE PM is projected 

to contain the full range of oil components based on the good agreement between the estimated 

unburned oil fraction and the measured OC fraction. This projection was found to be true for the 

lighter component eicosane, which was detected on average as 97 percent PM and only 3 percent 

gas phase. This percentage drops to 94 percent for the HE at 72oF and to 79 percent at 20oF 

(which has the lower EC levels). The heavier hexacosane was also found in HE PM at 94 
156 

percent at 72oF, but its PM fraction only drops to 91 percent at 20oF, indicating that this heavier 

hydrocarbon is displaced from the PM to a lesser extent than the lighter eicosane. This 

observation will be discussed further in the following discussion of PAH emissions. 

TABLE 71. DISPLACEMENT OF LIGHTER ALKANES FROM HE PM AT 

LOWER TEST TEMPERATURE

Alkane (Vehicle)

Percentage of Alkane in PM

72°F 20°F

C20H42 (NE) 95 98

C20H42 (HE) 94 79

C26H54 (HE) 94 91

8.6.6 PAH PM Emissions

PAH compounds are present in diesel fuel and many are also formed during the 

combustion process. A total of 55 PAH compounds were evaluated both in the gas phase and in 

PM of exhaust. The average total PAH PM emission rate was low for the NE, <0.1mg/mi (less 

than 0.3 percent of the OC). The HE has higher average total PAH PM emissions, ~1 mg/mi (~1 

percent of the OC) indicating a slightly higher OC contribution by the heavier components of the 

fuel and/or of fuel combustion. 

A comparison of the magnitude of two of the PAH compounds for the two test vehicles at 

the two test temperatures is presented in Table 72. This table illustrates the effectiveness of the 

NE’s oxidation catalyst in removing these PAH compounds from the exhaust. A slightly longer 

light-off time for the oxidation catalyst during the 20oF tests is also suggested by the increase in 

emissions. The increase in the two PAH emissions for the HE (no exhaust aftertreatment) at 

20oF may be related to the shift in combustion dynamics as was illustrated by the drop in EC 

emissions.

TABLE 72. TEMPERATURE AND OXIDATION CATALYST EFFECT ON 

SELECTED EMISSIONS RATES

PAH (Vehicle)

PM Emission Rate, μg/mi

72oF 20oF

Pyrene (NE) 1.3 10.1

Chrysene (NE) 0.3 4.1

Pyrene (HE) 101 149

Chrysene (HE) 15 29

The distribution of the PAH phenanthrene (C14H10) between the particle and gas phases is 

another example of the shifting dynamics of lighter hydrocarbons in the HE exhaust. For the 

72°F tests on the HE, 94 percent of the phenanthrene was collected as PM (139 μg/mi in PM vs 

9 μg/mi in vapor), but the particle-phase ratio drops to 40 percent at 20°F (66 μg/mi in PM vs 

98 μg/mi in vapor). On the other hand, the heavier and less volatile PAH pyrene (C16H10) is 

collected as 99+ percent PM at 72°F (101 μg/mi in PM vs <1 μg/mi in vapor) and 97 percent at 

20°F (149 μg/mi in PM vs 4 μg/mi in vapor). While the distribution of SVOCs in the NE 
157 

exhaust is relatively consistent across the testing conditions, there is a possible shift of SVOCs 

between the particle and gas phases for the HE, especially in the case of varying test temperature

(Table 73). It is reasonable to assume that while a variety of sampling conditions would be 

expected to give consistent exhaust samples for the NE, variations in collection protocols could 

produce different results with variations in sampling media, sample flow rate, etc. for the HE. 

For example, a slightly higher sampling flow rate at higher sample temperature could shift the 

distribution of SVOCs from PM to vapor phase much more easily in the case of the HE. This 

possibility would help explain some of the inconsistencies of the HE data, but makes a 

characterization of the PM more difficult.

TABLE 73. DISPLACEMENT OF LIGHTER PAHS FROM HE PM AT 

LOWER TEST TEMPERATURE

PAH (Vehicle)

Selected PAHs as Percent of Total PAH in PM

72°F 20°F

Phenanthrene (HE) 94 40

Pyrene (HE) 99+ 97

8.6.7 PM Apportionment Summary 

A number of data analyses were conducted in order to evaluate the make-up and origin of 

PM from the two medium-duty test vehicles. Several approaches were successful and provided 

useful information, while others illustrated the complexity of the exhaust environment. The 

following are some of the observations made in these analyses.

• Elements in oil were used to estimate an oil consumption rate. 

• An estimated oil consumption rate for the normal emitter was determined to be a 

nominal 0.16 quarts per 1000 miles; however, no measured values were available for 

comparison. 

• An estimated oil consumption rate for the high emitter matched a measured oil 

consumption rate of 0.49 quarts per 1000 miles. 

• Total carbon emission rates, along with corrections for measured elements and 

organic hydrogen, were similar to the measured PM rates for the normal emitter, but 

not as similar for the high emitter. 

• A hexatriacontane-d74 tracer and hopane/sterane totals were utilized to estimate 

unburned oil emission rates that were similar to the OC measurements for the normal 

emitter. Corresponding estimations for unburned oil emission rates for the high 

emitter resulted in values higher than the OC emission rates. 

• The carbon fraction of the NE average unburned oil emission rate (34 mg/mi) was 

determined to be 29 mg/mi (after removing the mass of associated hydrogen atoms). 

This remaining carbon from the unburned oil represents 83 percent of the measured 

OC. The much higher levels of expected unburned oil in HE PM and the 

displacement of lighter SVOCs with heavier SVOCs in the HE PM would indicate 

that this percentage would even be higher for the HE. 

• Alkane and PAH analyses illustrate the complex dynamics of the SVOCs between gas 

and particle phases in the HE exhaust. 
158 

• The potential of varying results for PM composition using different sampling 

protocols is also illustrated in the case of the HE.

8.7 Medium-Duty Diesel Vehicles Major Technical Findings

Fresh and Aged oil

PM emissions nominally decreased with aged oil in the normal emitter, but nominally 

increased from the high emitter.

TxLED Diesel (B0) and Twenty Percent Biodiesel (B20) Fuel

PM emissions from the normal emitter were not consistently affected by B20, but 

nominally increased from the high emitter.

Normal (72°F) and Low (20°F) Temperature

During cold tests, PM emissions nominally increased in all cases with the NE, but 

nominally decreased in all cases with the HE. 

Particle Number and Size Distributions

Particle Number 

• For the normal emitter, the exhaust PN concentration ranged from about 10x106 part./cm3 to 

20x106 part./cm3. 

• For the normal emitter, no major differences in PN emissions were observed between 72oF 

and 20oF, or between the cold-start and the hot-start portions of the cycle.

• The use of B20 in the NE resulted in lower solid and volatile PN emission, compared to B0. 

The PN reduction was on the order of 15 to 20 percent. 

• The MD NE vehicle with fresh oil emitted more solid and volatile particles, compared to PN 

emissions with the aged oil. This trend was observed during both the cold-start and the hotstart portions of the drive cycle. This trend was also consistent with what was observed with

the light-duty NE. 

• Fifty to eighty-three percent of the number of particles emitted from the MD NE was solid in 

nature.

• For the MD high emitter (HE), the exhaust PN concentration ranged from 12x106 part./cm3 to 

23x106 part./cm3. 

• No consistent trend was observed in PN emissions between B0 and B20. 

• For the HE, no major differences in PN were observed between 20oF and 75oF, or between 

cold-start and the hot-start portions of the cycle.

• PN emissions from the MD HE, particularly solid PN, were higher with the aged oil 

compared to fresh oil. This is consistent with the observation made with the light duty HE 

between aged oil and fresh oil, although the trend with the MD HE was not as pronounced. 

• For the high emitter, solid PN ranged from 26 to 65 percent of total PN. This range was 

lower than observed with the MD NE, suggesting more volatile PN with the MD HE, 

compared to the MD NE. 
159 

Particle Size Distribution

• For the NE and HE, the solid particle distributions exhibited a similar monomodal lognormal 

size distribution structure that consists of an accumulation mode with peaks between 50 nm 

and 70 nm. The total particle size distribution exhibited a bimodal lognormal distribution 

structure with a volatile nuclei mode peak between 10 nm and 20 nm. 

• A more pronounced volatile nuclei mode was observed at 20°F compared to 72°F, and with 

the HE versus the NE. For example, the NE had a small nuclei mode, particularly at 72°F, 

compared to the accumulation mode, where with the HE, the nuclei mode reached a peak 

level that is comparable with the peak of the accumulation mode at 72°F, and a higher peak 

level at 20°F. The increase in volatile nuclei mode particles can be indicative of increased oil 

consumption using similar technology vehicles with similar fuel and oil usage.

MD PM Apportionment

• An estimated oil consumption rate for the normal emitter was determined to be a nominal 

0.16 quarts per 1000 miles; however, no measured values were available for comparison. 

• A calculated oil consumption rate for the high emitter matched a measured oil consumption 

rate of 0.49 quarts per 1000 miles. 

• Total carbon emission rates, along with corrections for measured elements and organic 

hydrogen, were similar to the measured PM rates for the normal emitter, but did not correlate 

as well for the high emitter.

• A hexatriacontane-d74 tracer and hopane/sterane totals were utilized to estimate unburned oil 

emission rates that were similar to the OC measurements for the normal emitter. 

Corresponding estimations for unburned oil emission rates for the high emitter resulted in 

values higher than the OC emission rates.

• The carbon fraction of the NE average unburned oil emission rate was determined to be 29 

mg/mi (after removing the mass of associated hydrogen atoms). This remaining carbon from 

the unburned oil represents 83 percent of the measured OC. 

• Alkane and PAH analyses illustrate the complex dynamics of the SVOCs between gas and 

particle phases in the HE exhaust.

• The potential of varying results for PM composition using different sampling protocols is 

clearly illustrated with the HE.
160 

9.0 HEAVY-DUTY NATURAL GAS VEHICLE TESTS

9.1 Vehicle Selection and Description

Vehicle selection was made in collaboration with the CLOSE Project Management Team. 

SwRI identified potential candidate vehicles for testing and made vehicle recommendations to 

the CLOSE Project Management Team. We then waited for technical approval prior to 

procuring the test vehicles. One vehicle from each of the following categories was recruited:

9.1.1 Heavy-Duty Natural Gas Vehicle Selection Criteria

• Normal-emitting natural gas vehicle: This was to be a modern compressed CNG- or 

LNG-fueled transit bus or school bus of model year 2002 or newer with fewer than 

270,000 miles on the odometer. The natural gas engine of this vehicle was to have an 

advertised displacement of at least 7.6 liters and a minimum rated torque of 660 ftlbs. This vehicle was expected to be solicited from a Texas transit agency.

• High-emitting natural gas vehicle: This was to be a high-mileage CNG- or LNGfueled transit bus or school bus, preferably one that was known to emit measurable 

levels of PM, have high lubrication oil consumption, and/or have visible smoke 

related to lubrication oil. The natural gas engine of this vehicle was to have an 

advertised displacement of at least 7.6 liters and a minimum rated torque of 660 ftlbs. This vehicle was expected to be solicited from a Texas transit agency, and 

expected to be near the end of its useful life. 

9.1.2 Heavy-Duty Natural Gas Vehicle Selection and Description 

SwRI spent months searching for the heavy-duty natural gas vehicles for the study. 

SwRI contacted fleets in Texas and New Mexico regarding testing of heavy-duty natural gas 

vehicles. Contacted fleets and notes on their responses are listed below:

• City of Houston-‘Metro’ had no CNG vehicles in its fleet.

• City of Fort Worth-‘The-T’ had CNG buses but none were available. 

• City of Austin-‘Capital Metro’ had only diesel buses in their fleet.

• City of San Antonio-‘VIA’ the local transit authority did not have any CNG buses. 

• City of Dallas-‘DART’ had two fleets of LNG buses. Fleet 1 is 1998 Nova buses 

powered by Cummins L10G engines. Fleet 2 is 2002 Nova buses powered by Detroit 

Diesel Corporation (DDC) S50G engines. The 1998 buses were re-powered in 2004-

2005. The eleven 2002 buses were repowered in 2008 and 34 remain to be 

repowered. They said that the 2002 buses would be the best candidates. They 

searched for a recently rebuilt engine, and an end-of-life high oil consuming engine or 

an end-of-life low/normal oil consuming engine. They made no commitments and no

vehicles were available. 

• City of El Paso-‘Sun Metro’ has CNG vehicles in their fleet. We spoke with their 

Assistant Director for Maintenance and he was not interested is helping us. He stated 

there was ‘nothing in it for him.’
161 

• City of Albuquerque ‘NM-Transit Department’ had, from what we have found on the 

internet, CNG buses in their fleet. None were available.

• We sent an e-mail to the Natural Gas Transit Users Group requesting contact 

information for transit agencies that have CNG buses in their fleet. We did not 

receive any additional helpful information. 

• We corresponded with the coordinator of the Clean Cities Alamo Area Council of 

Government (AACOG). He gave us contact names and numbers for the City of San 

Antonio Fleet Maintenance and Operations but no NG vehicles were in their fleet. 

The problems we had locating suitable heavy-duty natural gas vehicles were shared with 

the CLOSE Project sponsors. Mike Bogdanoff, of South Coast Air Quality Management District 

(SCAQMD) made inquiries in California and located two CNG-fueled buses from Foothill 

Transit in Los Angeles, CA. SwRI and Foothill Transit signed a lease agreement (at no cost) to 

borrow each of the buses for one month. Mr. Bogdanoff made arrangements, through 

SCAQMD, to fund the shipping of both vehicles to and from San Antonio. Table 74 describes 

the two heavy-duty natural gas fueled buses that Mr. Bogdanoff procured for the project. A 

“high emitter” was not identified from the fleet of available natural-gas vehicles, and a high 

mileage bus was substituted in its place.

TABLE 74. DESCRIPTION OF HEAVY-DUTY NATURAL GAS BUSES

Normal Emitter High Mileage

Coach Number 1502 1317

Make North American Bus Industries (NABI) Orion Bus Industries (Orion)

Model 40.31 Orion V

Year 2006 2003

GVWR, lb 42,540 40,780

VIN 1N90403166A140162 1VHBH3C2236502059

Mileage 162,366 335,064

Engine Make Cummins Detroit Diesel S-50G

Fuel Strategy Lean-burn Lean-burn

Aftertreatment Catalytic Muffler Catalytic Muffler

Engine oil spec. 15W-40 15W-40

Because the HD natural gas and HD diesel vehicles did not exhibit higher PM emissions, 

they are designated as “high mileage” (HM). 

9.1.3 Gaseous and PM Emissions Check-out Tests

Before any tests were performed, the North American Bus Industries (NABI) bus normal 

emitter was operated at 50 mph for one hour on the dynamometer to condition the dilution 

tunnel. A series of hot-start UDDS test cycles were then run to assess the repeatability of the 

bus’s emissions. Table 75 shows the results of the repeatability tests conducted. Repeatability 

of gaseous emissions and fuel economy was quite good with the largest covariance exhibited by 

NOX emissions at 13.8 percent. The repeatability of PM emissions was not as good as gaseous 

emissions, with a covariance of 20.3 percent. The NABI bus was approved for testing by the 

CLOSE project participants.
162 

TABLE 75. SUMMARY OF REPEATABILITY CHECK TEST RESULTS FROM THE 

HEAVY-DUTY NORMAL PM EMITTING NATURAL GAS VEHICLE

(No Statistical Analyses Were Performed On These Data)

Test Number

HD-NE-FNG-REP1HD-NE-FNG-REP2HD-NE-FNG-REP3HD-NE-FNG-REP4HD-NE-FNG-REP5 AverageStandard 

Deviation Covariance

HC, g/mile 13.94 14.83 13.92 14.55 15.79 14.61 0.77 5.3%

CO, g/mile 1.16 1.29 1.09 1.12 1.13 1.16 0.08 6.9%

NOX, g/mile 7.55 8.02 7.26 6.87 5.47 7.03 0.97 13.8%

PM, g/mile 0.013 0.019 0.021 0.024 0.022 0.020 0.004 20.3%

Fuel Economy, lb/mile 1.44 1.48 1.37 1.43 1.45 1.43 0.04 2.7%

NMHC, g/mile 1.09 1.19 1.20 1.35 1.43 1.25 0.14 11.0%

CH4, g/mile 12.85 13.64 12.72 13.20 14.36 13.35 0.66 5.0%

Note: These tests are not part of the particulate characterization tests.

Tests were performed at a nominal 72°F, with commercial fuel and lubricant as received.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the 

number of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of 

comparisons across different temperatures, fuels or lubricants cannot be rigorously verified.

Prior to the testing for record of the natural gas fueled heavy-duty normal PM emitter, the 

engine was flushed and filled with fresh oil that had hexatriacontane tracer blended into it, after 

which it was operated for 150 miles on the road. Subsequently, buses accumulated 150 miles of 

operation on the dynamometer after each oil change, and conditioned the exhaust dilution tunnel 

at the same time.

The second natural gas bus (Orion) with higher mileage, which was expected to have 

higher PM emissions, was also emission tested for repeatability before running any tests for 

record. Prior to repeatability tests, the bus was operated at 50 mph for one hour on the 

dynamometer to condition the tunnel. A series of hot-start UDDS test cycles were then run to 

assess the repeatability of the bus’s emissions. Table 76 shows the emission test results of the 

repeatability tests conducted. Repeatability of gaseous emissions and fuel economy was quite 

good with the largest covariance exhibited by NOX emissions at 14 percent. The repeatability of 

PM emissions was not as good as with gaseous emissions, with a covariance of 28 percent. 

Although the ORION bus’s PM emissions were similar to the low PM emissions NABI bus, it 

was approved for testing by the CLOSE Project sponsors as a high-mileage vehicle.

TABLE 76. SUMMARY OF REPEATABILITY CHECK TEST RESULTS FROM THE 

HEAVY-DUTY HIGH MILEAGE NATURAL GAS VEHICLE

(No Statistical Analyses Were Performed On These Data)

Test Number

HD-HM-FNG-REP1HD-HM-FNG-REP2HD-HM-FNG-REP3HD-HM-FNG-REP4HD-HM-FNG-REP5 AverageStandard 

Deviation Covariance

HC, g/mile 13.60 15.78 14.26 14.46 14.98 14.62 0.82 6%

CO, g/mile 6.44 6.80 5.69 6.15 6.56 6.33 0.43 7%

NOX, g/mile 7.78 5.59 5.87 5.98 6.40 6.32 0.86 14%

PM, g/mile 0.022 0.031 0.017 0.019 0.016 0.021 0.006 28%

Fuel Economy, lb/mile 1.45 1.29 1.28 1.28 1.28 1.31 0.08 6%

NMHC, g/mile 0.88 0.97 0.89 0.93 0.93 0.92 0.03 4%

CH4, g/mile 12.72 14.82 13.37 13.52 14.05 13.70 0.79 6%

These tests are not part of the PM characterization tests.

Tests were performed at a nominal 72°F, with commercial fuel and lubricant as received.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the 

number of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of 

comparisons across different temperatures, fuels or lubricants cannot be rigorously verified.
163 

9.2 Lubricants

The heavy-duty vehicles were tested with both fresh and aged lubricants. Their 

description and the supplier’s analyses are included in Section 5.1 in Tables 3 and 6. The drain 

and fill procedure is described in Section 5.1. Degreening of the lubricants was accomplished by 

operating the heavy-duty vehicles for 150 miles on the road or on the chassis dynamometer. Oil 

samples include the fresh and aged oils as received, and one oil sample each taken after 

completion of all tests on fresh and then aged oils from the normal- and high-mileage emitter. 

For example, the normal emitter was operated over multiple emission tests with fresh oil and a 

sample was taken from the crankcase drain oil, and then the normal emitter was operated over 

multiple emissions tests with aged oil and a sample was taken from the crankcase drain oil. Thus 

two oil samples were taken from the normal-emitter (fresh and aged oil), and two oil samples 

were taken from the high-mileage emitter.

9.3 Fuels

Fuel systems on all vehicles were flushed with the test fuels prior to the initiation of 

testing. SwRI utilized on-site blending facilities to custom-blend batches of natural gas. Natural 

gas composition was analyzed to ensure accurate accounting of fuel speciation and molecular 

weight. Additionally, utility line gas that was delivered with the vehicles was used for 

dynamometer setup and degreening of the first test lubricant. For the natural gas vehicles, the 

gas contained in the fuel tanks of each vehicle was isolated from the fuel intake system using the 

fuel shut-off valves available on each vehicle. A pressurized container of natural gas was

positioned outside of the test cell and a hose directed fuel into the test vehicle’s fuel intake 

system. The heavy-duty diesel vehicles were fueled directly from an underground tank dedicated 

to the project. Analyses results for the natural gas blends used for heavy-duty tests are included 

in Section 5.2.4. 

9.4 Emission Test Procedures

This is a pilot study of exhaust emissions effects from the use of different fuels and 

lubricants with some tests conducted at different temperatures. It is important to note that the 

scope of work in this study is limited to short-term effects on emissions when a fuel or lubricant 

was changed. The fuels and lubricants used in this study could have long-term effects on 

emissions which were not measured.

9.4.1 Driving Cycle

Heavy-duty vehicles were evaluated over the EPA Urban Dynamometer Driving 

Schedule (UDDS) for Heavy-Duty Vehicles. The heavy-duty UDDS is also known as the heavyduty chassis cycle (HDCC). The HDDC cycle is shown in Figure 73. The duration of the 

HDCC is 1,060 seconds, and the cycle covers a distance of 5.55 miles. The official use of this 

cycle is for conditioning heavy-duty gasoline-fueled vehicles before an evaporative emissions 

test. However, the HDCC is commonly used for exhaust emissions testing of heavy-duty 

vehicles for research purposes, and was based on the engine speed and load conditions used to 

compile the EPA heavy-duty diesel engine transient test cycle used for emissions certification. 

Vehicles were operated over a series of cold- and hot-start tests conducted on the same day. For 
164 

all emission tests, the vehicles were soaked for at least 12 hours at test temperature prior to 

emissions evaluations.

FIGURE 73. HEAVY-DUTY UDDS (HDDC) CYCLE

Engine preparation was accomplished by operating the vehicle over two HDCC cycles 

followed by a least a 12 hour soak. Tunnel conditioning was conducted in conjunction with the 

accumulation of 150 miles operation after each oil change and engine preparations. 

• Normal-Emitting Natural Gas Vehicle: Based on results from replicate tests 

performed before beginning PM testing for analysis, six HDDCs (one cold and five 

hot-starts) were performed for each sample. Thus 24 HDDCs were performed in 

order to collect all 4 samples (2 oils × 2 replicate samples × 6 HDDCs per sample).

• High-Mileage Natural Gas Vehicle: In order to parallel the testing of the normalemitting CNG vehicle, SwRI tested this vehicle over the same number of replicate 

cold- and hot-start HDDCs.

9.4.2 Chassis Dynamometer

Testing of heavy-duty vehicles utilized SwRI’s heavy-duty tandem-axle chassis 

dynamometer manufactured by Reliance Electric Engineered Systems and Burke-Porter. The 

chassis dynamometer is equipped with two sets of 48-inch rolls designed to accommodate one or 

two drive axles. Each set of 48-inch rolls is coupled to a 300 horsepower dynamometer. The 

chassis dynamometer system is capable of simulating 4,500 lbs of equivalent vehicle weight 

mechanically and 60,000 lbs of equivalent vehicle weight electrically. 

 

 

0

10

20

30

40

50

60

70

0 200 400 600 800 1000

Time, sec.

Speed, mph
165 

9.5 Heavy-Duty Natural Gas Vehicles Emission Test Results

9.5.1 Regulated Gaseous and PM Emissions

Note that longer range precision was not rigorously explored in the test design. Thus 

statistical significance of comparisons across different temperatures, fuels or lubricants cannot be 

rigorously verified. Average results from both heavy-duty natural gas vehicles are shown in 

Table 77. Regulated gaseous emissions, PM emissions, and fuel consumption rates while 

operating the vehicles with fresh and aged oil are included. All heavy-duty emission tests were 

conducted at a nominal 72oF ambient temperature. Repeatability of the emissions from the 

replicate tests was good. PM emission rates measured from the high mileage (HM) bus on aged 

oil showed the greatest variability between the two replicate tests with a covariance of 15 

percent. NOX emissions from the normal emitter (NE) also exhibited higher variability with 

covariance of 11 and 12 percent on fresh and aged oil, respectively. In addition, non-methane 

hydrocarbon emissions from the normal emitter on fresh oil showed a covariance of 14 percent, 

but all other emission rates exhibited low variability with covariances below 10 percent.

TABLE 77. AVERAGE REGULATED EMISSIONS FROM HEAVY-DUTY

NATURAL GAS VEHICLES

(No Statistical Analyses Were Performed On These Data)

72o F - Average of Replicate Testsa

Normal Emitter High Mileage

Fresh Oil Aged Oil Fresh Oil Aged Oil

Average

Standard 

Deviation

Coefficient 

of 

Variation Average

Standard 

Deviation

Coefficient 

of 

Variation Average

Standard 

Deviation

Coefficient 

of 

Variation Average

Standard 

Deviation

Coefficient 

of 

Variation

HC, g/mile 13.4 0.33 2% 14.4 0.78 5% 14.4 0.68 5% 14.6 0.78 5% 

CO, g/mile 1.28 0.04 3% 1.47 0.07 5% 6.50 0.33 5% 7.37 0.70 9% 

NOx, g/mile 10.9 1.19 11% 12.6 1.53 12% 7.3 0.03 0% 9.5 0.26 3% 

PM, mg/mileb 18.2 0.27 1% 14.2 0.77 5% 17.9 0.39 2% 22.2 3.26 15% 

Fuel Usage, lb/mile 1.46 0.01 1% 1.41 0.02 1% 1.33 0.01 1% 1.33 0.02 1% 

NMHC, g/mile 2.35 0.33 14% 2.82 0.03 1% 2.52 0.08 3% 2.83 0.15 5% 

CH4, g/mile 11.0 0.04 0.4% 11.6 0.81 7% 11.9 0.75 6% 11.8 0.63 5% a Each replicate test consisted of one cold HDDC cycle plus five hot HDDC cycles. b PM as determined from phase-by-phase filter samples collected during each test.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where 

n is the number of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical 

significance of comparisons across different temperatures, fuels or lubricants cannot be rigorously verified.

We note that NOX emissions measured from the heavy-duty natural gas bus with normal 

PM emissions during repeatability tests differed from those measured during the tests for record. 

The average hot-start NOX rate during the repeatability tests was 7.0 g/mile, and the average hotstart NOX rate during all of the NE tests for record was 10.8 g/mile. The only difference in 

operation of the vehicle was the fuel used for the tests, and we suspect that the fuel change 

caused the change in NOX emissions. During the repeatability tests, we ran on the fuel stored on 

the bus as it was received from California. During all the tests for record, we ran on a SwRI 

blend of gases that meets both Federal and California certification fuel concentration protocols. 

Table 78 compares the analyses of the two fuels.
166 

The methane number of each fuel blend is a measure of the knock resistance of the fuel, 

and was calculated using the California Air Resources Board (ARB) mathematical method. The 

Wobbe index is a measure of the interchangeability of fuel gases such as natural gas, LPG and 

butane, and is calculated by dividing the higher heating value of the fuel by its relative density. 

It has been shown in other programs conducted at SwRI that both the Wobbe Index and methane 

number directly affect NOX. A link to a final report for one of these programs can be found at: 

http://www.socalgas.com/business/gasQuality/documents/swri_final_report_cummins_johndeere

detroitdiesel.pdf. 

TABLE 78. SUMMARY OF NORMAL EMITTER BUS TANK AND SWRI BLENDED

NATURAL GAS FUEL ANALYSES

(No Statistical Analyses Were Performed On These Data)

Fuel Blend

Normal Emitter 

Bus Tank

SwRI 

Blended Sphere

Methane Number - 101.4 88.5 

Wobbe Index BTU/scf 1331 1334 

Methane % vol 96.0 90.2 

Ethane % vol 1.8 4.5 

Propane % vol 0.3 1.9 

N-Butane % vol 0.1 0.0 

Carbon Dioxide % vol 1.04 0.00 

Nitrogen % vol 0.8 3.4 

Total % vol 100.00 100.00 

If the methane number decreases, then NOX is expected to increase. Conversely, if the 

Wobbe Index decreases, then NOX is expected to decrease. Since the Wobbe Indices of both 

fuels are similar, we would not expect NOX to change much due to the fuel change. But the 

methane numbers are very different and we do expect the NOX would increase when operating 

on the SwRI blended fuel. 

 Although the hydrocarbon emissions rates of the repeatability tests were similar to the 

tests for record, the methane emissions were lower in the tests for record. This resulted in the 

repeatability test’s non-methane hydrocarbon (NMHC) emissions to be much lower than the 

NMHC emissions from the tests for record. We suspect that the NMHC differences are due to 

the different fuels used. As with the low PM emitter, the high mileage bus’s repeatability tests 

were also performed with the fuel in the bus as received from California. We did not analyze the 

high mileage natural gas bus’s tank fuel but it is probably similar to the low-emitter’s tank fuel 

which had more methane than the SwRI blend, which would reduce NMHC emissions from both 

vehicles during their repeatability tests. 
167 

9.5.1.1 Discussion of Regulated Emissions Results

 Figures 74 through 78 show the average emission test results presented in Table 76. Note 

that long range precision was not thoroughly explored in the test design. Thus, statistical 

significance of comparisons across different temperatures, fuels, or lubricants cannot be 

rigorously verified. Average hydrocarbon emissions from the heavy-duty natural gas buses are 

shown in Figure 74. Hydrocarbon emission rates were similar from each vehicle. Average 

hydrocarbon rates on fresh oil with normal emitter were less than with aged oil, but the highmileage bus’s rates were very similar with both oils. 

FIGURE 74. HYDROCARBON EMISSION RATES FROM THE NORMAL PM EMITTER 

AND HIGH MILEAGE NATURAL GAS BUSES

(No Statistical Analyses Were Performed On These Data)

Average CO emissions from all the heavy-duty natural gas tests are shown in Figure 75. 

Both buses produced less CO emissions on fresh oil compared to aged oil. The normal PM 

emitter produced much less CO than the high mileage bus. The low emitter could have operated 

leaner, or its catalyst could be more efficient than the high-mileage bus. Average oxides of 

nitrogen emissions shown in Figure 76 also indicate leaner operation of the normal emitter since 

it produced higher NOX emissions than the high-mileage bus. However, the two natural gas 

buses have different engines which also could explain the differences in their CO and NOX

emissions. NOX emissions increased with the use of aged oil with both buses. 

Fuel usage in pound per mile units from the heavy-duty natural gas vehicles is shown in 

Figure 77. The normal emitter exhibited worse fuel economy than the high-mileage bus. This is 

most likely attributable to the relative efficiency their engines. The normal emitter exhibited 

better fuel economy with aged oil compared to fresh oil, but the high mileage bus did not show 

any change in fuel economy with the change to aged oil. 

13.4 14.4 14.4 14.6

0

2

4

6

8

10

12

14

16

18

NE-F-NG-72 NE-A-NG-72 HE-F-NG-72 HE-A-NG-72

HC, g/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL
168 

 Figure 78 shows the PM emissions from the heavy-duty natural gas buses. On fresh oil, 

the PM rates from both vehicles were very similar. On aged oil, PM rates from the normal 

emitter decreased but the high mileage vehicle’s PM emissions increased. The reason why PM 

emissions trended in opposite directions when oil was switched from fresh to aged is unknown. 

FIGURE 75. CARBON MONOXIDE EMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE NATURAL GAS BUSES

(No Statistical Analyses Were Performed On These Data)

FIGURE 76. OXIDES OF NITROGEN EMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE NATURAL GAS BUSES

(No Statistical Analyses Were Performed On These Data)

1.28 1.47 6.50 7.37

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

NE-F-NG-72 NE-A-NG-72 HE-F-NG-72 HE-A-NG-72

CO, g/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL

10.9 12.6 7.3 9.5

0

2

4

6

8

10

12

14

16

18

NE-F-NG-72 NE-A-NG-72 HE-F-NG-72 HE-A-NG-72

NOx, g/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL
169 

FIGURE 77. FUEL CONSUMPTION OF THE NORMAL PM EMITTER AND HIGH 

MILEAGE NATURAL GAS BUSES

(No Statistical Analyses Were Performed On These Data)

FIGURE 78. PARTICULATE MATTER EMISSION RATES FROM THE NORMAL

PM EMITTER AND HIGH MILEAGE NATURAL GAS BUSES

(No Statistical Analyses Were Performed On These Data)

1.46 1.41 1.33 1.33

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

NE-F-NG-72 NE-A-NG-72 HE-F-NG-72 HE-A-NG-72

FU, lb/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL

18.2 14.2 17.9 22.2

0

5

10

15

20

25

30

35

NE-F-NG-72 NE-A-NG-72 HE-F-NG-72 HE-A-NG-72

PM, mg/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL
170 

9.5.2 PM and SVOC Analyses

PM from the heavy-duty natural gas vehicle tests were characterized by analyzing them 

for elements, semi-volatile organic compounds (SVOC), elemental and organic carbon (EC/OC), 

sulfates, and soluble organic fraction (SOF) at DRI. In the following PM characterization 

subsections, Tables 79 through 86 present the results of these analyses. Data shown for PM in 

Tables 79 through 86 are the averages of the replicate tests performed in each configuration. 

The spreadsheet of light-duty PM analyses results which was devised by Dr. Fujita to 

investigate the light-duty PM characterization results was used as a template for the heavy-duty 

natural gas PM characterization results. The spreadsheet includes the results from the individual 

tests, and is posted at an ftp site at SwRI for CLOSE participants. Dr. Lawrence Smith of SwRI 

used the spreadsheet data to identify elements and compounds of interest in the apportionment 

study presented in Section 9.6. 

9.5.2.1 X-Ray Fluorescence (XRF)

PM sampled from the heavy-duty natural gas tests was analyzed by DRI for elements by 

XRF. Table 79 shows the average results in μg/mile of the replicate tests performed in each 

configuration, and the results of lubricant analysis in μg/gram. The configurations are identified 

in the top rows of the table, and elements measured are shown in the left column. 

9.5.2.2 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Analysis

 PM sampled from the heavy-duty natural gas tests was analyzed by DRI for eighteen 

elements by ICP-MS. Table 80 shows the average results from PM in μg/mile of the replicate 

tests performed in each configuration. Table 80 also shows the results of elemental analysis of 

the lubricants performed at EAI Inc. EAI measured five more elements in the lubricants than 

DRI measured in the particulate matter. Elements found in lubricants are presented in nanogram 

(ng) per gram of oil units. The configurations are identified in the top rows of the table, and 

elements measured are shown in the left column. 

9.5.2.3 Polycyclic Aromatic Hydrocarbons

Exhaust emissions sampled from the heavy-duty natural gas tests were analyzed by DRI 

for polycyclic aromatic hydrocarbons (PAH). Table 81 shows the average results from PM in 

μg/mile of the replicate tests performed in each configuration. Table 81 also shows the results of 

lubricant analyses for PAHs in μg/gram units. Table 28 shows the codes for the PAH species in 

Table 81. 

9.5.2.4 Alkanes 

Exhaust emissions sampled from the heavy-duty natural gas tests were analyzed by DRI 

for alkanes. Table 82 shows the average results in μg/mile of the replicate tests performed in 

each configuration. Table 30 shows the codes for the alkane species in Table 82. Table 82 also 

shows the results of lubricant analyses for alkanes in μg/gram units. 
171 

9.5.2.5 Hopanes and Steranes

Exhaust emissions sampled from the heavy-duty natural gas tests were analyzed by DRI 

for hopanes and steranes. Table 83 shows the average results in μg/mile of the replicate tests 

performed in each configuration. Table 33 shows the codes for the hopanes and steranes species 

in Table 83. Table 83 also shows the results of lubricant analyses for hopanes and steranes in 

μg/gram units. 

9.5.2.6 Particle-Phase Elemental and Organic Carbon 

 PM sampled from the heavy-duty natural gas tests was analyzed by DRI for elemental 

carbon and organic carbon (EC/OC). Table 84 shows the average results in mg/mile of the 

replicate tests performed in each configuration. The configurations are identified in the five left 

columns of the table, and EC/OC results are shown in the three right columns. In Table 84, EC 

is elemental carbon measured, OC is organic carbon, and TC is total carbon. 

9.5.2.7 Particulate-Phase Sulfates

Particulate matter sampled from the heavy-duty natural gas tests was analyzed by DRI for 

sulfates. Table 85 shows the average results in μg/mile of the replicate tests performed in each 

configuration. 

9.5.2.8 Particulate-Phase Soluble Organic Fraction 

 PM sampled from the heavy-duty natural gas tests was analyzed by DRI for soluble 

organic fraction (SOF). Table 86 shows the average results for the normal emitter and high 

emitter, in percent SOF, of the replicate tests performed in each configuration.
172 

TABLE 79. SUMMARY AVERAGE HEAVY-DUTY NATURAL GAS VEHICLE PM 

AND LUBRICANT ELEMENTAL ANALYSIS BY XRF

(No Statistical Analyses Were Performed On These Data)

Elemental Emission Rates, μg/mile Lubricant Elements, μg/gram

Test Number

HD-NE-FNG-72HD-NEA-NG-72HD-HM-FNG-72HD-HM-ANG-72HD-NE-FNG-72HD-NEA-NG-72HD-HM-FNG-72HD-HM-ANG-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72

Na 560 519 56 208 0 0 0 0

Mg 105 163 0 0 0 0 0 0

Al 0 0 44 40 0 0 0 0 

Si 35 12 139 134 0 0 0 0

P 818 857 575 551 101 0 89 3 

S 2618 1731 460 561 3046 2271 3147 2079

Cl 4 4 5 5 0 0 0 0 

K 7 7 15 16 0 0 0 0

Ca 1823 1871 1220 1508 1828 1826 1823 1753 

Sc 0 0 3 3 0 0 0 0

Ti 0 1 10 10 0 0 0 0

Va 1 0 0 0 0 0 0 0

Cr 25 30 18 43 1 1 1 2

Mn 7 18 4 30 0 0 0 0 

Fe 1509 2737 539 546 10 23 2 27

Co 0 0 0 0 0 0 0 0 

Ni 27 39 16 35 0 0 0 0

Cu 6 12 12 16 0 21 0 7 

Zn 1102 1077 762 813 1152 582 1117 525

Ga 0 0 0 0 0 0 0 0 

As 0 0 0 0 0 0 0 0

Se 0 0 0 0 0 0 0 0

Br 0 0 0 0 0 0 0 0 

Rb 0 0 0 0 0 0 0 0

Sr 1 1 1 3 0 0 0 0 

Yt 0 0 0 0 0 0 0 0

Zr 1 0 5 3 0 0 0 0 

Nb 0 0 0 0 0 0 0 0

Mo 30 79 20 112 35 292 33 276 

Pd 0 0 0 0 0 0 0 0

Ag 0 0 0 0 0 0 0 0 

Cd 0 0 1 0 0 0 0 0

In 0 1 0 1 0 0 0 0

Sn 0 0 0 0 0 0 0 0 

Sb 1 0 0 0 0 0 0 0

Cs 0 0 0 0 0 0 0 0 
173 

TABLE 79 (CONT'D). SUMMARY AVERAGE HEAVY-DUTY NATURAL GAS 

VEHICLE PM AND LUBRICANT ELEMENTAL ANALYSIS BY XRF

(No Statistical Analyses Were Performed On These Data)

Elemental Emission Rates, μg/mile Lubricant Elements, μg/gram

Test Number

HD-NE-FNG-72HD-NEA-NG-72HD-HM-FNG-72HD-HM-ANG-72HD-NE-FNG-72HD-NEA-NG-72HD-HM-FNG-72HD-HM-ANG-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72

Ba 0 6 4 0 0 0 0 0

La 0 5 0 0 0 0 0 0

Ce 0 0 0 0 0 0 0 0 

Sm 0 2 4 0 0 0 0 0

Eu 4 0 0 0 0 0 0 0 

Tb 0 0 1 8 0 0 0 0

Hf 0 0 0 0 0 0 0 0 

Ta 0 0 0 0 0 0 0 0

Wo 0 0 0 0 0 0 0 0 

Ir 0 0 0 0 0 0 0 0

Au 0 0 0 0 0 0 0 0

Hg 0 0 0 0 0 0 0 0

Tl 0 0 0 0 0 0 0 0

Pb 1 1 2 5 1 7 0 6 
174 

TABLE 80. RESULTS OF HEAVY-DUTY NATURAL GAS PM AND LUBRICANTS ELEMENTAL ANALYSIS BY ICP-MS

(No Statistical Analyses Were Performed On These Data)

Test

Number

Average Particulate Elements, μg/mile Lubricant Elements, ng/gram

HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72 HD-NE-F-NG HD-NE-A-NG LO-223360 LO-223291

Emitter Normal Normal High Mileage High Mileage Normal Normal As-received As-received

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72.0 72.0 72.0 72.0 72 72 72 72

Mg 226.8 224.1 46.5 33.0 10792 22435 5165 13118

Al 13.6 10.6 176.0 90.9 771 1558 471 1412

Ca 826.6 849.7 522.9 529.0 1492876 1484968 1498063 1383799

Va 0.1 0.2 0.2 0.1 35 21 34 21

Cr 8.8 11.9 5.1 16.8 179 274 24 254

Mn 1.5 5.2 6.3 22.8 187 236 60 219

Fe 959.0 1452.9 619.6 328.6 6375 15223 1790 18074

Ni 18.5 28.6 11.7 20.0 240 300 74 418

Cu 3.9 9.6 5.2 8.1 508 19973 22 9644

Zn 782.1 805.3 538.9 509.7 923229 495975 942587 424717

Mo 22.1 62.0 20.3 80.0 31565 267178 32171 293420

Ag 0.1 0.1 0.0 0.1 5 193 <LODa 114

Cd 0.0 0.0 0.0 0.0 0 0 0 0

Sn 0.2 0.3 0.1 0.5 0 0 0 0

Ba 1.3 1.5 11.7 10.9 22 76 12 68

Ce 0.8 2.1 20.4 12.4 0 0 0 0

Hg 0.0 0.0 0.0 0.0 0 0 0 0

Pb 0.9 1.8 2.5 4.0 631 6254 34 5455

W NMb NM NM NM 7 41 5 52

P NM NM NM NM 747579 386806 787657 336946

S NM NM NM NM 3378529 2461678 3375411 2275117

Ti NM NM NM NM <LOD 35 29 30

Sr NM NM NM NM 497 536 464 449 a Less than Level of Detection

b Not measured
175 

TABLE 81. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE POLYCYCLIC AROMATIC HYDROCARBONS

IN EXHAUST AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test

Number

PAHs, μg/mile Lubricant PAHs, μg/gram 

HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72 HD-NE-F-NG HD-NE-A-NG HD-HM-F-NG HD-HM-A-NG

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72 

Media a F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction b Yes Yes Yes Yes NA NA NA NA

naphth 60.9 14.5 63.0 161.1 29.6 30.7 31.9 25.9 

quinoline 1.4 0.0 4.6 6.1 0.0 0.0 0.0 0.0 

mnaph2 57.2 0.0 95.7 119.5 25.8 29.7 30.3 26.2 

mnaph1 33.8 0.0 54.0 72.6 12.7 13.2 16.2 13.8 

biphen 4.0 0.7 3.9 14.0 0.6 0.7 0.7 0.9 

m_2bph 0.0 0.0 26.4 44.0 0.0 0.2 0.0 0.0 

dmn267 16.3 0.0 19.5 25.1 4.7 5.6 6.9 6.9 

dm1367 24.4 0.0 32.6 39.1 6.0 9.6 11.6 11.6 

d14523 8.5 0.0 16.8 15.6 0.6 1.5 2.4 2.4 

enap12 6.9 0.0 17.2 22.1 2.4 2.2 1.7 1.7 

acnapy 2.1 0.4 7.2 13.7 0.0 0.0 0.0 0.0 

dmn12 1.6 0.0 4.8 6.2 0.0 0.2 0.0 0.6 

dmn18 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 

acnape 0.1 0.0 0.4 1.9 7.1 0.0 0.0 0.0 

m_3bph 0.0 0.0 23.4 41.4 0.0 1.7 1.4 1.8 

m_4bph 0.0 0.0 7.2 15.1 0.0 0.5 5.3 0.6 

dbzfur 1.9 1.1 2.8 6.6 0.0 0.0 0.0 0.0 

em_12n 5.3 3.7 16.8 23.5 0.0 0.3 0.0 0.2 

tmi235n 6.2 0.6 11.3 9.4 0.4 0.8 4.1 3.1 

btmnap 4.0 0.0 10.7 9.8 0.9 2.1 3.9 3.4 

atmnap 12.6 0.2 14.3 17.0 0.0 1.1 0.6 1.9 

ctmnap 1.4 0.0 10.2 9.6 0.0 0.8 3.2 3.0 

em_21n 0.1 0.0 0.6 0.4 0.0 0.0 0.0 0.0 

etmnap 1.9 0.0 5.9 6.5 1.1 1.0 2.8 1.7 

tm245n 0.9 0.0 2.5 3.1 0.0 0.1 0.6 0.4 
176 

TABLE 81 (CONT'D). HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE POLYCYCLIC AROMATIC HYDROCARBONS 

IN EXHAUST AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test

Number

PAHs, μg/mile Lubricant PAHs, μg/gram 

HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72 HD-NE-F-NG HD-NE-A-NG HD-HM-F-NG HD-HM-A-NG

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72 

Media a F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction b Yes Yes Yes Yes NA NA NA NA

ftmnap 2.2 0.0 6.9 6.3 0.6 1.2 3.3 2.8 

fluore 0.4 0.0 5.2 6.5 0.0 0.1 0.6 0.7 

tm145n 0.0 0.0 2.2 2.4 0.0 0.2 0.4 0.7 

jtmnap 2.8 0.4 3.7 2.3 0.0 0.2 0.6 0.4 

a_mfluo 0.0 0.0 1.0 0.9 0.2 0.5 2.0 2.7 

b_mfluo 0.0 0.0 0.4 0.4 0.0 0.0 0.4 0.2 

m_1fluo 0.5 0.0 1.5 0.8 0.2 0.2 1.8 1.2 

fl9one 0.0 0.0 5.9 14.5 0.0 0.0 0.0 0.0 

phenan 0.0 0.0 7.0 11.5 0.6 2.6 4.4 4.7 

anthra 0.0 0.0 1.1 2.0 0.1 0.7 2.3 2.4 

xanone 0.0 0.0 0.4 1.3 0.0 0.0 0.1 0.2 

acquone 0.0 0.1 0.5 0.0 0.0 0.0 0.0 0.0 

m_2phen 1.2 0.0 1.0 2.3 1.1 3.2 3.2 6.0 

m_3phen 0.0 0.0 2.1 2.4 1.0 4.0 3.7 6.6 

pnapone 0.2 0.1 3.6 5.2 0.0 0.3 0.6 0.6 

m_2anth 0.0 0.0 0.3 0.2 0.0 2.0 4.1 4.8 

m_45phen 0.0 0.0 0.1 2.4 0.4 0.6 0.7 0.6 

m_9phen 0.0 0.0 0.9 3.6 0.0 1.2 1.7 2.5 

mpht_1 0.3 0.2 0.8 0.8 0.0 1.7 1.2 2.0 

anthron 0.0 0.0 0.0 1.8 0.0 2.0 1.1 3.9 

m_9ant 0.0 0.0 0.1 0.0 0.2 0.1 0.0 0.2 

nap2phen 0.0 0.0 0.0 0.4 0.2 0.5 0.8 0.7 

anrquone 0.0 0.0 0.7 1.3 0.0 0.2 0.0 0.3 

a_dmph 0.0 0.1 0.3 0.8 0.2 3.1 1.2 1.5 

b_dmph 0.0 0.0 0.0 0.2 0.0 2.0 0.4 0.9 

dm17ph 0.0 0.0 0.0 0.1 0.5 2.7 1.4 2.2 

dm36ph 0.0 0.0 0.1 0.3 0.1 1.2 0.0 1.6 
177 

TABLE 81 (CONT'D). HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE POLYCYCLIC AROMATIC HYDROCARBONS 

IN EXHAUST AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test

Number

PAHs, μg/mile Lubricant PAHs, μg/gram 

HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72 HD-NE-F-NG HD-NE-A-NG HD-HM-F-NG HD-HM-A-NG

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72 

Media a F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction b Yes Yes Yes Yes NA NA NA NA

d_dmph 0.0 0.0 0.1 0.2 0.2 0.9 1.7 1.5 

e_dmph 0.0 0.0 0.0 0.7 0.1 2.3 0.8 3.2 

c_dmph 0.0 0.0 0.1 0.3 0.8 5.0 3.5 6.8 

fluora 0.0 0.0 0.9 1.3 0.1 0.4 0.3 0.7 

pyrene 0.5 0.0 1.3 2.3 0.2 5.6 1.8 8.2 

antal9 0.0 0.0 0.0 0.0 0.5 1.7 1.1 2.5 

retene 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.2 

bafluo 0.0 0.0 0.1 0.0 0.7 1.2 0.4 2.8 

bbfluo 0.0 0.0 0.0 0.0 0.2 0.6 0.7 0.7 

bmpyfl 0.0 0.0 0.1 0.0 0.8 1.4 0.5 3.3 

c1mflpy 0.0 0.0 0.0 0.0 0.1 0.5 0.7 0.4 

m_13fl 0.0 0.0 0.1 0.1 0.8 1.0 0.5 2.6 

m_4pyr 0.0 0.0 0.1 0.8 1.1 6.6 1.3 12.0 

cmpyfl 0.0 0.0 0.0 0.0 0.3 1.1 1.2 1.3 

dmpyfl 0.0 0.0 0.0 0.2 0.4 10.8 1.2 15.8 

m_1pyr 0.0 0.0 0.0 0.1 0.5 4.9 0.7 7.4 

bntiop 0.0 0.0 0.0 0.2 0.5 0.5 0.0 0.6 

bzcphen 0.0 0.0 0.0 0.1 0.3 0.3 0.3 0.4 

bghifl 0.0 0.0 0.2 0.4 0.2 0.8 0.6 0.2 

phant9 0.0 0.0 0.3 0.1 0.1 0.2 0.0 0.2 

cp_cdpyr 0.3 0.0 0.4 0.1 0.1 0.3 0.4 0.2 

baanth 0.0 0.1 0.0 0.1 0.1 2.8 0.8 2.8 

chr_tr 0.1 0.0 0.0 0.5 0.5 1.8 0.8 4.3 

bzanthr 0.1 0.1 0.1 0.6 1.1 1.7 0.9 1.7 

baa7_12 0.0 0.0 0.0 0.3 0.8 3.8 1.3 2.1 

m_3chr 0.0 0.0 0.0 0.2 0.3 0.9 0.7 2.4 

chry56m 0.0 0.0 0.0 0.0 0.7 1.0 0.8 0.6 
178 

TABLE 81 (CONT'D). HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE POLYCYCLIC AROMATIC HYDROCARBONS 

IN EXHAUST AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test

Number

PAHs, μg/mile Lubricant PAHs, μg/gram 

HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72 HD-NE-F-NG HD-NE-A-NG HD-HM-F-NG HD-HM-A-NG

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72 

Media a F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction b Yes Yes Yes Yes NA NA NA NA

m_7baa 0.0 0.0 0.0 0.0 0.9 0.8 0.7 0.5 

dmban712 0.0 0.0 0.0 1.7 0.3 0.3 0.9 0.2 

bbjkfl 0.0 0.0 0.0 0.4 0.3 0.3 0.1 0.4 

bafl 0.0 0.0 0.0 0.0 0.2 0.2 0.1 0.0 

bepyrn 0.0 0.0 0.1 0.4 0.2 0.5 0.2 0.2 

bapyrn 0.0 0.0 0.0 0.1 0.4 0.5 0.2 0.5 

peryle 0.2 0.0 0.0 0.1 0.4 0.2 0.0 0.4 

m_7bpy 0.1 0.1 0.1 0.0 0.2 0.2 0.2 0.2 

bpy910dih 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 

incdfl 0.0 0.0 0.0 0.1 0.6 0.5 0.9 0.5 

dbahacr 0.0 0.0 0.0 0.0 0.6 0.2 0.1 0.1 

dbajacr 0.0 0.0 0.0 0.0 0.2 0.3 0.4 0.5 

in123pyr 0.0 0.0 0.1 0.1 0.4 0.4 0.4 0.3 

dbahacan 0.0 0.0 0.0 0.0 0.7 0.7 1.8 0.7 

dbajan 0.0 0.0 0.0 0.0 0.7 0.9 0.4 0.4 

bbchr 0.0 0.0 0.0 0.0 0.5 0.6 0.7 0.7 

pic 0.0 0.0 0.0 0.0 0.0 1.2 0.0 0.5 

bghipe 0.1 0.0 0.6 0.7 0.6 0.5 1.0 0.7 

anthan 0.0 0.0 0.1 0.0 0.3 0.2 1.1 0.7 

dbalpyr 0.0 0.0 0.0 0.0 0.2 0.3 0.2 1.4 

corone 0.0 0.0 0.2 0.3 0.3 0.2 0.0 0.4 

dbaepyr 0.0 0.0 0.0 0.1 0.0 0.9 0.0 0.2 

dbaipyr 0.0 0.0 0.0 0.1 0.5 0.3 0.0 0.0 

dbahpyr 0.0 0.0 0.0 0.1 0.3 0.4 0.0 0.0 

dbbkfl 0.0 0.0 0.0 0.0 0.5 0.7 0.0 0.9 

dbth 0.0 0.0 0.0 0.4 0.4 0.4 0.4 0.4 a Filter + XAD cartridge samples or oil samples.

b Test samples were corrected by subtracting the average tunnel blank measurement.
179 

TABLE 82. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE ALKANES IN EXHAUST AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test

Number

Alkanes Emission Rates, μg/mile Lubricant Alkanes, μg/gram

HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72 HD-NE-F-NG HD-NE-A-NG HD-HM-F-NG HD-HM-A-NG

Source Exhaust Exhaust Exhaust Exhaust Oil Oil Oil Oil

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72

Media a F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction b Yes Yes Yes Yes NA NA NA NA

dodec 216.9 0.0 0.0 71.3 0.0 0.3 0.9 0.4

norfarn 62.3 0.0 0.3 42.8 15.1 0.0 0.0 0.0

tridec 116.1 0.0 0.0 114.4 0.0 0.4 1.4 1.3

hpycyhx 13.8 1.0 0.0 13.4 0.0 0.0 0.0 0.0

farnes 51.4 0.5 0.0 31.7 0.0 0.0 0.0 0.0

tdec 553.2 0.0 24.0 164.0 2.2 4.0 5.1 4.0

ocycyhx 4.5 0.0 0.0 11.5 0.0 0.0 0.1 0.0

pentad 92.5 11.7 38.5 132.5 1.7 5.4 4.8 4.1

noycyhx 8.7 1.1 2.4 13.2 0.1 0.0 0.2 0.1

hexad 15.9 4.4 25.1 82.9 14.8 21.9 21.5 17.1

norprst 7.4 7.8 13.5 33.2 0.5 0.4 3.1 0.7

decyhx 0.0 2.1 4.6 8.8 0.2 0.2 0.6 0.1

heptad 11.1 0.0 22.2 62.1 42.1 67.6 63.7 63.8

heptdpris 7.6 2.3 16.2 32.2 2.2 5.1 8.9 2.1

dec1yhx 0.2 0.0 0.6 1.5 0.9 2.0 4.6 1.9

octad 6.8 0.0 16.9 31.3 29.6 38.9 46.1 39.5

phytan 4.7 0.0 12.8 21.9 18.1 15.9 30.7 15.2

dec2yhx 0.1 0.1 3.5 2.5 5.8 1.5 9.2 4.7

nonad 4.9 0.5 12.4 16.6 39.4 60.0 62.6 55.3

dec3yhx 0.0 0.0 1.4 1.4 9.4 11.4 12.0 10.7

eicosa 1.4 0.0 7.1 10.2 67.4 113.7 100.9 107.2

dec4yhx 0.0 0.0 0.3 1.1 28.7 24.2 33.4 30.7

heneic 0.0 0.0 4.7 7.7 94.1 111.1 130.1 121.9

dec5yhx 0.0 0.0 1.0 1.1 53.0 75.9 83.3 69.2

docosa 0.0 0.0 3.7 4.7 78.0 107.8 102.4 109.5

dec6yhx 0.1 0.1 0.3 0.5 12.1 5.5 15.2 51.1
180 

TABLE 82 (CONT'D). HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE ALKANES IN EXHAUST AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test

Number

Alkanes Emission Rates, μg/mile Lubricant Alkanes, μg/gram

HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72 HD-NE-F-NG HD-NE-A-NG HD-HM-F-NG HD-HM-A-NG

Source Exhaust Exhaust Exhaust Exhaust Oil Oil Oil Oil

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72

Media a F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction b Yes Yes Yes Yes NA NA NA NA

tricosa 0.0 0.0 4.3 2.4 61.9 87.0 76.9 100.8

dec7yhx 0.2 0.0 0.4 3.5 76.0 121.1 102.6 117.5

tetcos 0.0 0.0 0.0 1.1 51.9 56.6 37.6 82.9

dec8yhx 0.0 0.0 4.2 9.2 33.5 7.6 11.9 72.2

pencos 0.0 0.0 3.3 6.6 75.0 138.4 152.6 159.2

hexcos 0.0 0.0 2.8 1.7 110.6 102.7 185.1 94.1

dec9yhx 0.0 0.0 0.8 0.9 9.0 10.2 27.0 7.7

hepcos 0.0 0.1 5.6 2.3 35.4 25.1 102.3 90.8

cyhxeic 0.0 0.0 0.4 0.4 76.9 57.1 48.3 64.5

octcos 0.0 0.0 3.5 2.6 52.0 38.3 21.2 120.4

noncos 0.0 0.0 2.0 2.3 41.9 74.0 32.2 22.4

cyhxhen 0.2 0.3 0.5 0.1 29.0 22.4 4.8 10.9

tricont 0.0 0.0 1.0 1.9 27.4 8.9 15.3 22.2

htricont 0.0 0.0 1.1 3.1 21.1 7.5 46.4 1.4

dtricont 0.0 0.0 0.8 1.7 6.3 24.1 8.3 6.6

ttricont 0.0 0.0 0.4 1.6 2.9 4.2 16.8 3.7

tetricont 0.0 0.0 0.2 0.0 7.4 4.5 29.4 20.5

ptricont 0.0 0.0 0.0 0.2 10.0 0.1 1.1 3.4

hxtricont 0.0 0.0 0.0 0.0 2.0 2.6 4.4 7.1

hptricont 0.0 0.0 0.0 0.0 11.0 10.4 2.3 5.8

otricont 0.0 0.0 0.1 0.1 5.8 2.3 6.9 4.8

ntricont 0.0 0.0 0.0 0.1 4.2 3.0 0.7 5.7

tecont 0.0 0.0 0.2 0.1 4.6 2.0 4.4 8.1

hxtric74 4.6 2.2 8.0 8.1 380.2 317.4 372.2 370.9

ucm 1735 515 5473 8027 179758 191638 190729 206337 a Filter + XAD cartridge samples or oil samples.

b Test samples were corrected by subtracting the average tunnel blank measurement.
181 

TABLE 83. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE HOPANES AND STERANES IN EXHAUST AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Test 

Number

Hopanes and Steranes Emission Rates, μg/mile Lubricant Hopanes and Steranes, μg/gram

HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72 HD-NE-F-NG-72 HD-NE-A-NG-72 HD-HM-F-NG-72 HD-HM-A-NG-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel NG NG NG NG NG NG NG NG

Temp, oF 72 72 72 72 72 72 72 72

Media a F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction b Yes Yes Yes Yes NA NA NA NA

hop15 0.0 0.1 0.6 0.9 31.7 32.6 47.0 51.7 

hop17 0.2 0.2 2.4 2.8 98.2 121.0 164.0 94.6 

hop19 0.0 0.5 1.7 2.0 59.9 77.1 94.5 62.1

hop20 0.0 0.0 0.0 0.0 1.7 2.9 0.0 2.0

hop21 0.0 0.9 1.5 2.0 44.6 56.1 89.2 49.6

hop22 0.0 0.4 0.6 0.8 29.6 40.7 78.9 29.2

hop23 0.1 0.1 0.1 0.0 4.4 7.7 11.2 5.0

hop24 0.1 0.1 0.5 0.8 24.7 29.3 70.6 24.6

hop25 0.1 0.2 0.4 0.6 14.3 24.0 67.2 19.5 

hop26 0.1 0.1 0.3 0.4 12.6 15.8 34.9 17.3 

hop27 0.0 0.0 0.2 0.3 9.0 11.9 56.9 16.7 

ster42 0.1 0.0 0.1 0.1 9.7 7.2 4.1 6.5 

ster43 0.1 0.0 1.3 0.6 32.2 31.2 35.0 29.3

ster44 0.0 0.0 0.8 0.3 15.5 15.6 15.0 16.6

ster45_40 0.1 0.1 0.4 0.4 27.1 26.4 18.2 21.6

ster46 0.0 0.0 0.3 0.1 3.5 3.7 2.2 4.3

ster47 0.0 0.0 0.3 0.3 15.6 15.4 16.2 17.7

ster48_41 0.0 0.0 0.1 0.0 9.5 10.3 8.5 6.6 

ster49 0.0 0.0 0.1 0.1 2.1 1.8 4.2 2.2 

ster50 0.0 0.0 0.2 0.2 8.9 9.1 8.2 8.9 

ster51 0.0 0.0 1.2 0.3 17.6 19.6 16.4 18.8 

ster52 0.0 0.1 0.2 0.2 12.6 13.9 11.2 13.2

ster53 0.1 0.0 0.1 0.3 11.8 12.9 14.5 11.6 a Filter + XAD cartridge samples or oil samples.

b Test samples were corrected by subtracting the average tunnel blank measurement.
182 

TABLE 84. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE ELEMENTAL CARBON 

AND ORGANIC CARBON RATES

(No Statistical Analyses Were Performed On These Data)

CARBON EMISSION RATE, mg/mile

Test Number Emitter Oil Fuel Temp, oF EC OC TC

HD-NE-F-NG-72 Normal Fresh

Natural 

Gas 72 0.96 7.26 8.22

HD-NE-A-NG-72 Normal Aged

Natural 

Gas 72 1.52 7.63 9.14

HD-HM-F-NG-72

High 

Mileage Fresh

Natural 

Gas 72 0.46 16.84 17.30

HD-HM-A-NG-72

High 

Mileage Aged

Natural 

Gas 72 1.20 22.71 23.90

TABLE 85. AVERAGE SULFATE EMISSIONS FROM HEAVY-DUTY NATURAL GAS 

VEHICLES

(No Statistical Analyses Were Performed On These Data)

Test Number Emitter Oil Fuel Temp

Average Sulfate, 

μg/mile

HD-NE-F-NG-72 Normal Fresh Natural Gas 72 6531

HD-NE-A-NG-72 Normal Aged Natural Gas 72 4205

HD-HM-F-NG-72 High Mileage Fresh Natural Gas 72 1086

HD-HM-A-NG-72 High Mileage Aged Natural Gas 72 1147

TABLE 86. HEAVY-DUTY NATURAL GAS VEHICLE AVERAGE SOLUBLE ORGANIC 

FRACTION

(No Statistical Analyses Were Performed On These Data)

Test Name Lubricant Vehicle Fuel

Ambient 

Temperature, oF

Average 

SOF, %

HD-NE-F-NG-72 Fresh Normal Emitter Natural Gas 72 9%

HD-NE-A-NG-72 Aged Normal Emitter Natural Gas 72 15%

HD-HM-F-NG-72 Fresh High Mileage Natural Gas 72 66%

HD-HM-A-NG-72 Aged High Mileage Natural Gas 72 72%
183 

9.5.2.9 Particle Number and Size Distribution Emission Test Results

Figures 79 and 80 show the exhaust PN concentration for the heavy-duty natural gas 

normal emitter (HD-NG-NE). The data are shown for the fresh and aged oil at 72°F. The data are 

plotted as an average concentration for the cold-start and for one subsequent hot-start of the HD 

UDDS. The exhaust PN concentration ranged from about 6x106 part./cm3 to 15x106 part./cm3. 

This is comparable in range to the diesel MD-NE, but as can be seen later, the particle size 

distribution is vastly different. More PN emissions were observed during the hot-start portion of 

the cycle, compared to the cold-start. Fresh oil produced higher PN emissions than the aged oil, 

particularly volatile PN. This trend was observed previously with the gasoline LD-NE. Figures 

81 and 82 show the percent ratio of solid and volatile PN concentration to total PN 

concentration. Twenty five to fifty-five percent of the number of particles emitted from the HDNG-NE were solid in nature. 

Figures 83 and 84 show the exhaust PN concentration for the HD-NG high mileage 

emitter (HM). The exhaust PN concentration ranged from 10x106 part./cm3 to 55x106 part./cm3. 

This highest PN concentration is higher than the PN concentration observed with the MD NE 

and HE. However, it was 63 percent lower than the highest PN concentration observed with the 

light duty HE. Fresh oil showed higher PN emissions than aged oil under cold-start. Under hotstart, the PN emission was comparable between the fresh and the aged oil. Figures 85 and 86

show that over 80 percent of the PN were volatile particles. This is similar to what was observed 

previously with the gasoline LD-HE.

It is known that heavy-duty natural gas engines produce very little PM when the engine is 

tuned properly and lube oil consumption is low. The high volatile PN emissions observed in this 

study are likely due to sulfuric acid and volatile and semi-volatile hydrocarbon particle formation 

during dilution and cooling of hot exhaust. The origin of sulfuric acid is from the presence of 

sulfur in the fuel (if any) and lube oil. Sulfur is oxidized in combustion and in the exhaust over 

an oxidation catalyst to produce SO3. SO3 reacts with water in the exhaust to form sulfuric acid. 

Sulfuric acid nucleates into particles during exhaust cooling and dilution. 

The origin of volatile and semi-volatile hydrocarbon is mainly due to unburned and 

partially burned lube oil. The origin of solid particles in natural gas engines can be due to 

multiple factors. First, soot formation in natural gas combustion is a plausible scenario, but 

perhaps unlikely with the lean burn natural gas engines tested in this program. Another 

mechanism is soot formation by pyrolysis of semi-volatiles in the lube oil. This mechanism is 

more plausible in stoichiometric natural gas engines with a lack of excess oxygen rather than in 

lean burn natural gas engines. A third plausible mechanism for solid particle emissions from 

natural gas engines is metal oxides and/or sulfated ash emissions derived from the lube oil. The 

presence of these particles typically shows up in the nuclei mode part of the size distribution, as 

shown below. 
184 

FIGURE 79. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(NATURAL GAS, NORMAL EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 80. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION

(NATURAL GAS, NORMAL EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)
185 

FIGURE 81. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(NATURAL GAS, NORMAL EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data) 

FIGURE 82. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(NATURAL GAS, NORMAL EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)
 

 

Exhaust Particle Number Concentration,

Part./cm3 

6.0E+07 

5.0E+07 

4.0E+07 

3.0E+07 

2.0E+07 

1.0E+07 

1.0E+05 

HM, Cold-Start, Fresh Oil HM, Hot-Start, Fresh Oil 

Cold-Start-72°F Hot-Start-72°F 

Solid Particles Volatile Particles 

FIGURE 83. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION 

(NATURAL GAS, HIGH MILEAGE EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data) 

6.0E+07 

Exhaust Particle Number Concentration,

Part./cm3 

5.0E+07 

4.0E+07 

3.0E+07 

2.0E+07 

1.0E+07 

1.0E+05 

Cold-Start-72°F Hot-Start-72°F 

Solid Particles Volatile Particles 

HM, Cold-Start, Aged Oil HM, Hot-Start, Aged Oil 

FIGURE 84. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION 

(NATURAL GAS, HIGH MILEAGE EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data) 

186 
187 

FIGURE 85. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES 

(NATURAL GAS, HIGH MILEAGE EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 86. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(NATURAL GAS, HIGH MILEAGE EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Cold-Start-72°F Hot-Start-72°F

Number Fraction, %

Solid Particles Volatile Particles

HM, Cold-Start, Fresh Oil HM, Hot-Start, Fresh Oil

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Cold-Start-72°F Hot-Start-72°F

Number Fraction, %

Solid Particles Volatile Particles

HM, Cold-Start, Aged Oil HM, Hot-Start, Aged Oil
188 

Figures 87 and 88 show a typical size distribution for the HD-NG-NE using the fresh and 

aged oil. The data are shown for the cold-start and hot-start portions of testing. The total and 

solid distributions seem to exhibit a similar monomodal lognormal size distribution structure that 

consists of a nuclei mode. The nuclei mode peaks at 10 nm. Similar size distributions are 

observed with the HD-NG-HM, as shown in Figures 89 and 90. The cold start with fresh oil 

showed a higher concentration and growth of particles, but the growth was not as strong as what 

was seen with the gasoline LD-HE. In the case of the LD-HE, volatile particle size reached 50 to 

60 nm in diameter with a higher number concentration, compared to the HD-NG-HM. The 

reduction in volatile nuclei PN emissions with the aged oil, compared to fresh oil, could be 

related to the loss of lube oil volatile material that plays a role in particle nucleation and/or 

growth. This phenomenon is worth investigating further in future research. The solid size 

distributions for the HD-NG vehicles have a small peak at 10 nm diameter. The solid particles 

are likely to be ash particles from the lube oil, but further work is needed to investigate the 

nature of the nuclei mode solid particles emitted from the HD-NG-HM. 

FIGURE 87. NUMBER-WEIGHTED SIZE DISTRIBUTION (NATURAL GAS, NORMAL 

EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)
189 

FIGURE 88. NUMBER-WEIGHTED SIZE DISTRIBUTION (NATURAL GAS, NORMAL 

EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)

FIGURE 89. NUMBER-WEIGHTED SIZE DISTRIBUTION (NATURAL GAS, HIGH 

MILEAGE EMITTER, FRESH OIL) 

(No Statistical Analyses Were Performed On These Data)

0.00E+00

5.00E+05

1.00E+06

1.50E+06

2.00E+06

2.50E+06

3.00E+06

3.50E+06

4.00E+06

1 10 100 1000

Average Number Concentration [part/cm3]

Particle Diameter [nm]

72°F-Cold Start-Total

72°F-Cold Start-Solid

72°F-Hot Start-Total

72°F-Hot Start-Solid

HD, HM, 

Fresh Oil
190 

FIGURE 90. NUMBER-WEIGHTED SIZE DISTRIBUTION (NATURAL GAS, HIGH 

MILEAGE EMITTER, AGED OIL) 

(No Statistical Analyses Were Performed On These Data)

9.6 PM Apportionment Summary

For the heavy-duty vehicle evaluations, two natural gas-fueled vehicles and two dieselfueled vehicles were tested in duplicate using the Heavy-Duty Urban Dynamometer Driving 

Schedule with two crankcase oils (a “fresh oil” and an “aged oil”). The vehicles were tested 

either with natural gas or with diesel fuel as appropriate. A total of four tests (two with each of 

two oils) were conducted on each of the four vehicles. All four vehicles were equipped with 

catalytic converters. Two of the vehicles (one diesel-fueled and one natural gas-fueled) had been 

operated for considerably more mileage (100 to 150 thousand miles) than the other vehicle in the 

set and were designated as the high mileage (HM), while the lower mileage vehicles were 

designated as normal emitters (NE). It should be noted that the measured exhaust emission rates 

did not necessarily follow this designation. The same set of analyses that were conducted on the 

medium-duty vehicles’ exhaust were also conducted for the heavy-duty vehicles. More details 

related to the description of the vehicles, test cycle, fuels, lubricating oil, and analytical 

procedures can be found in Section 6 and in previous subsections of this section (9.1 through 

9.4). 

The same approach to analyzing the data that was followed for the medium-duty vehicles 

was also followed for the heavy-duty vehicles. Because each of the two sets of vehicles not only 

used different fuels, but also different lubricating oils; the evaluations were divided into two 

subparts, one for the natural gas-fueled vehicles and one for the diesel-fueled vehicles.

0.00E+00

5.00E+05

1.00E+06

1.50E+06

2.00E+06

2.50E+06

3.00E+06

3.50E+06

4.00E+06

1 10 100 1000

Average Number Concentration [part/cm3]

Particle Diameter [nm]

72°F-Cold Start-Total

72°F-Cold Start-Solid

72°F-Hot Start-Total

72°F-Hot Start-Solid

HD, HM,

Aged Oil
191 

9.6.1 Regulated Emissions and Fuel Economy 

Regulated emissions and fuel economy data for each set of duplicate tests conducted on 

each of the two natural gas-fueled vehicles were averaged and are presented in Table 87. 

TABLE 87. REGULATED EMISSIONS AND FUEL ECONOMY FOR HEAVY-DUTY 

NATURAL GAS-FUELED VEHICLES

(No Statistical Analyses Were Performed On These Data)

NE HM

Fresh Oil Aged Oil Fresh Oil Aged Oil

HC, g/mi 13.37 14.44 14.39 14.63

CO, g/mi 1.28 1.47 6.50 7.37

NOx, g/mi 10.86 12.57 7.34 9.52

PM, mg/mi 18 14 18 22

Fuel Usage, lbs/mi 1.46 1.41 1.33 1.33

*Results are the average of duplicate tests

The largest numerical difference in the regulated emissions between the two test vehicles 

was in the carbon monoxide emissions which were nominally lower for the NE than for the HM 

(possibly due to a more active catalyst on the lower mileage NE). Hydrocarbons, carbon 

monoxide, and oxides of nitrogen emissions nominally increased with the use of the aged oil, but 

PM emissions had opposing trends for the two test vehicles. 

9.6.2 Estimates for Vehicle Oil Consumption Rates 

As was carried out for the medium-duty vehicles, elements found in both the exhaust PM 

and in the oil were utilized to calculate oil consumption rates for the two vehicles. There was, 

however, a disparity in the exhaust emission rates for the elements with the two methods of 

analysis, XRF and ICP-MS. The XRF results for many of the elements were, in general, found 

to be twice or more the level of those determined by ICP-MS. When no obvious solution for this 

disparity could be found, it was decided to calculate oil consumption rates using both sets. As 

was utilized for the medium-duty NE, calcium was selected for the calculations. Table 88 lists 

average emission rates and oil concentrations for calcium along with calculated oil consumption 

rates. Zinc (XRF and ICP-MS) and phosphorus (XRF) data gave oil consumption rates similar to 

those determined with calcium for both vehicles with the fresh oil, but nearly twice the calcium

determined rate for both vehicles with the aged oil. These higher rates were primarily due to 

similar exhaust emission for the elements with both oil, but the aged oil containing only one half 

the amount of zinc and phosphorus as did the fresh oil. 
192 

TABLE 88. ESTIMATED OIL CONSUMPTION RATES USING BOTH XRF &

ICP-MS DATA*

(No Statistical Analyses Were Performed On These Data)

NE HM 

Calcium Emissions, XRF, μg/mi 1848 1364

Calcium Emissions, ICP-MS, μg/mi 838 526

Calcium Oil Concentration, XRF, μg/g 1807 1807

Calcium Oil Concentration, ICP-MS, μg/g 1465 1465

Oil Consumption Rate, XRF, mg/mi** 1023 755

Oil Consumption Rate, ICP-MS, mg/mi** 572 359

 * Values in this table are averages for four tests, two with each oil

** An oil consumption rate of 833 mg/mi equals 1 quart per 1000 miles

As can be seen in Table 88, both XRF and ICP-MS results predict a higher oil 

consumption rate for the NE. Sulfur from the oil (the natural gas fuel was a synthetic blend and 

did not contain sulfur) was found in the NE PM exhaust at levels four times higher than those 

found for the HM. This difference in sulfur is not consistent with the difference in calculated oil 

consumption rates using the calcium emissions and could occur as a result of a more active 

catalyst on the NE (as was suggested earlier) converting more of the sulfur in the oil to sulfate. 

PM sulfate levels were five times higher for the NE than for the HM. 

9.6.3 Wear Elements

No unusual trends were noted for the typical wear elements observed in exhaust PM. As 

was the case for the elements originating in the oil, the two methods of analysis, XRF and ICPMS, gave different results for the wear elements in the exhaust. Both methods indicate higher 

concentrations of the wear element in the exhaust of the NE (1.3 to 2.3 mg/mi) as compared to 

the HM (0.7 mg/mi with both analytical methods). 

9.6.4 Carbon Analyses for “Elemental” and “Organic” Content of PM 

Elemental, organic, and total carbon content results from TOR analyses of the PM filters 

from the natural gas-fueled vehicle tests are presented in Table 89. The measured total PM 

results for each vehicle are also shown for comparison. While total PM and EC results are 

similar for the two vehicles, the organic carbon from the HM is more than twice that for the NE. 

Recall that the oil consumption rate as determined from elemental Ca was actually higher for the 

NE.
193 

TABLE 89. TOTAL, ELEMENTAL, AND ORGANIC CARBON EMISSIONS

(No Statistical Analyses Were Performed On These Data)

Emissions, mg/mi

NE HM 

Fresh Oil Aged Oil Fresh Oil Aged Oil

EC 1.0 1.5 0.5 1.2

OC 7.3 7.6 16.8 22.7

TC 8.2 9.1 17.3 23.9

PM 18 14 18 22

As was done with the MD vehicles, an attempt was made to account for the total PM 

mass by combining the measured carbon mass with a sum of oil and wear derived element 

masses (Table 90). Sulfur and phosphorus were assumed to be present as sulfate and phosphate 

and the organic carbon mass was assumed to contain 1.5 hydrogen atoms per carbon atom. As 

can be seen in the table, both vehicles have similar PM emission rates, but the make-up of the 

PM is very different. The NE is composed of only 40 percent organic related material (OC plus 

hydrogen), while the HM is made up of 80 percent organic material.

TABLE 90. CARBON AND OTHER ELEMENT TOTALS COMPARED TO TOTAL PM

(No Statistical Analyses Were Performed On These Data)

Emissions, mg/mi

NE HM 

Fresh Oil Aged Oil Fresh Oil Aged Oil

Total Carbon 8.2 9.1 17.3 23.9

Elements* 14.8 13.4 5.8 6.6

Hydrogen Mass for OC** 0.9 1.0 2.1 2.9

Total 23.9 23.5 25.2 33.4

Measured PM 18 14 18 22

*Element totals from XRF analysis. Mass for sulfur and phosphorus assumed to be sulfate and phosphate.

**Mass for 1.5 hydrogen per carbon assumed

9.6.5 Estimation of Unburned Oil Content

The oils used in this part of the study also contained a hexatriacontane-d74 tracer, which 

along with the total measured hopanes and steranes, were used to calculate unburned oil 

concentrations in the exhaust PM. Average PM hexatriacontane-d74 exhaust emission rates 

were found to be 4.3 μg/mi for the NE and 8.1 μg/mi for the HM. When the emission rates were 

divided by the average concentration of the hexatriacontane-d74 in the oil, 360 μg/g, unburned 

oil emission rates of 11.9 mg/mi for the NE and 22.5 mg/mi for the HM were obtained. Average 

emission rates for the total hopanes and steranes measured in this study were 1.3 μg/mi for the 

NE and 12.0 μg/mi for the HM. When the average total hopane and sterane concentration in the 

test oils, 624 μg/g, was used to calculate unburned oil concentrations, average emission rates of 

2.1 mg/mi for the NE and 19.2 mg/mi for the HM were obtained. A third estimate for the 
194 

unburned oil contribution to PM was made using an unresolved complex mixture total (UCM) 

obtained during the GC-MS alkane analysis. The PM emission rate for UCM was found to be 

1.1 mg/mi for the NE and 4.7 mg/mi for the HM. The oils, on average, were found to contain 

0.196 g/g oil of this unresolved material. Dividing the PM emission rate by the average oil 

concentration of the UCM gives a third estimate for the unburned oil contribution to PM, 

5.6 mg/mi for the NE and 24.0 mg/mi for the HM. 

Table 91 presents a comparison of these calculated unburned oil estimates to the organic 

carbon (OC) component of the PM. There appears to be good agreement of unburned oil 

estimates with the total OC for the HM, indicating that the OC is primarily unburned oil and that 

any one of the three methods could be utilized to make this prediction. For the NE, the use of 

hextriacontane-d74 over-estimates the OC of the PM, while the hopanes and steranes under 

estimate the OC. The UCM provides the best estimate of the three methods. The relative 

amount of the heavy hexatriacontane-d74 material is apparently increased in the NE PM by the 

volatilization of the lighter oil components (as was noted for the medium-duty HE vehicle), 

while the lighter hopanes and steranes are lost and are diminished in concentration. 

TABLE 91. COMPARISON OF UNBURNED OIL ESTIMATES TO OC

(No Statistical Analyses Were Performed On These Data)

Average Emission Rate for 

Normal Emitter, mg/mi

Average Emission Rate for 

High Mileage Emitter, 

mg/mi

Hexatriacontane-d74 11.9 22.5

Hopanes and Steranes 2.1 19.2

UCM 5.6 24.0

OC 7.5 19.8

9.6.6 PAH PM Emissions

As one may expect for these natural gas-fueled vehicles, the total PM PAH emission rates 

were extremely low (compared to the diesel-fueled vehicles); 0.6 μg/mi for the NE and 

7.7 μg/mi for the HM. The lower level of these combustion products in the NE exhaust was 

probably due to its more active catalyst. There was only a small numerical difference in total 

PM PAH compounds between the tests with fresh (0.9 μg/mi) and aged (0.3 μg/mi) oil for the 

NE, but a more perceivable difference was noted for the HM, 3.1 μg/mi for fresh oil and 

12.4 μg/mi for aged oil. The aged oil did contain higher concentrations of PAH compounds than 

did the fresh oil. 

Only two PAH compounds were found on all eight PM filters analyzed in this part of the 

study, benzo(ghi)perylene and coronene. These PAHs are two of the three PAHs used in the 

light-duty gasoline-fueled part of this study as markers for fuel-generated EC. In this case, 

however, these PAH markers did not trend with the EC emissions. The HM, which had slightly 

lower EC emissions (0.8 mg/mi) than the NE (1.2 mg/mi) had much higher PM emission rates 

for these two compounds, 878 ng/mi, than did the NE, 82 ng/mi. Once again, this difference is 

thought to be due to the more active catalyst on the NE. 
195 

9.6.7 Summary

The following are some of the observations made from the analyses of the emissions 

data.

• Carbon monoxide emissions were nominally lower for the NE compared to the HM, 

perhaps indicating a more active catalyst on the lower mileage NE.

• XRF and ICP-MS analyses gave different emission rates for the oil derived elements 

and subsequently different calculated oil consumption rates for the two vehicles. 

Both methods gave higher oil consumption rates for the NE than for the HM. 

• Sulfate PM emissions were nearly 5 times higher for the NE than for the HM, once 

again indicating a more active catalyst for the NE.

• OC emission rates indicate that as much as 99 percent of the consumed oil was 

burned or partially burned in either the combustion chamber or in the vehicles 

catalyst for the NE, while 95 to 98 percent of the consumed oil was burned or 

partially burned for the HM. 

• Both vehicles had similar PM emission rates, but the make-up of the PM was very 

different. The HM PM consisted of nearly 80 percent organic material, while the NE 

PM consisted of only 40 percent organic material. 

• Three different methods gave calculated unburned oil estimates for the HM that were 

in good agreement with the OC component of PM, indicating that the OC is primarily 

unburned oil and that any one of the three methods could be used to make this 

predication. 

• The hexatriacontane-d74 method over-predicted the unburned oil component of the 

NE PM, while hopane and sterane totals under-predicted this component, indicating 

an increase in the relative amount of the heavier oil components in the PM. 

• Both vehicles had relatively low PAH emission rates (0.6 to 7.7 μg/mi) compared to 

the diesel-fueled vehicles (500 μg/mi).

• High molecular weight PAH compounds found in light-duty exhaust 

(benzo(ghi)perylene and coronene) were also found in the exhaust of the natural gasfueled heavy-duty vehicles. The HM had lower PM emissions than the NE, but more 

than 10 times the level of these two PAH compounds. The more active catalyst on 

the NE may have been instrumental in the lower levels of these PAHs in the exhaust. 

9.7 Heavy-Duty Natural Gas Vehicles Major Technical Findings

Fresh and Aged Oil

The normal emitter produced similar PM emissions compared to the high-mileage vehicle on 

fresh oil and fresh lube produced more PM emissions than aged lube. 

Low and High Particulate Matter (High Mileage) Emitter

No trend in PM emissions was evident between the low emitter and the high-mileage vehicle. 

PM emission rates ranged from 14 to 22 mg/mi. 
196 

Normal (72°F) and Low (20°F) Temperature

No low temperature tests were performed with the HD natural gas vehicles.

Particle Number and Size Distributions

Particle Number 

• From the NE, the exhaust PN concentration ranged from about 6x106 part./cm3 to 15x106

part./cm3.This is comparable in range to the diesel MD NE, but the particle size distribution 

is vastly different.

• More PN emissions were observed from the NE during the hot-start portion of the cycle, 

compared to the cold-start.

• The NE on fresh oil produced higher PN emissions than with the aged oil, particularly 

volatile PN. This trend was observed previously with the gasoline LD NE.

• Twenty-five to fifty-five percent of the number of particles emitted from the HD NG NE 

were solid in nature.

• For the HD NG high mileage emitter, the exhaust PN concentration ranged from 10x106

part./cm3 to 55x106 part./cm3. This PN concentration is higher than the PN concentration 

observed with the MD NE and HE. However, it was 63 percent lower than the highest PN 

concentration observed with the light duty HE. 

• Fresh oil in the HM showed higher PN emissions than aged oil under cold-start. Under hotstart, the PN emission was comparable between the fresh and the aged oil.

• Over 80 percent of the HM PN emissions were volatile particles. This is similar to what was 

observed previously with the gasoline LD HE. 

Particle Size Distribution

• For the HD NG NE with both fresh and aged oil, the total and solid distributions seem to 

exhibit a similar monomodal lognormal size distribution structure that consists of a nuclei 

mode. The nuclei mode peaks at 10 nm. Similar size distributions are observed with the HD 

NG HM. 

• The cold start with fresh oil showed a higher concentration and growth of particles, 

compared to the aged oil, but the growth was not as strong as what was seen with the 

gasoline LD HE. In the case of the LD HE, volatile particle size reached 50 to 60 nm in 

diameter with higher number concentration, compared to the HD NG HM. 

• The reduction in volatile nuclei PN emissions with the aged oil, compared to fresh oil, could 

be related to the loss of lube oil volatile material that plays a role in particle nucleation and/or 

growth. This phenomenon is worth investigating in future research.

• The solid size distributions for the HD NG vehicles have a small peak at 10 nm diameter. 

The solid particles are likely to be ash particles from the lube oil, but further work is needed 

to investigate the nature of the nuclei mode solid particles emitted from the HD NG HM. 
197 

HD Natural Gas PM Apportionment

• Carbon monoxide emissions were nominally lower for the NE compared to the HM, perhaps 

indicating a more active catalyst on the lower mileage NE.

• XRF and ICP-MS analyses gave different emission rates for the oil derived elements and 

subsequently different calculated oil consumption rates for the two vehicles. Both methods 

gave higher oil consumption rates for the NE than for the HM. 

• Sulfate PM emissions were nearly 5 times higher for the NE than for the HM, once again 

indicating a more active catalyst for the NE.

• OC emission rates indicate that as much as 99 percent of the consumed oil was burned or 

partially burned in either the combustion chamber or in the vehicle’s catalyst for the NE, 

while 95 to 98 percent of the consumed oil was burned or partially burned for the HM. 

• Both vehicles had similar PM emission rates, but the make-up of the PM was very different. 

The HM PM consisted of nearly 80 percent organic material, while the NE PM consisted of 

only 40 percent organic material. 

• Three different methods gave calculated unburned oil estimates for the HM that were in good 

agreement with the OC component of PM, indicating that the OC is primarily unburned oil 

and that any one of the three methods could be used to make this predication. 

• The hexatriacontane-d74 method over-predicted the unburned oil component of the NE PM, 

while hopane and sterane totals under-predicted this component, indicating an increase in the 

relative amount of the heavier oil components in the PM.

• Both vehicles had relatively low PAH emission rates (0.6 to 7.7 μg/mi) compared to the 

diesel-fueled vehicles (~500 μg/mi). 

• High molecular weight PAH compounds found in light-duty exhaust (benzo(ghi)perylene and 

coronene) were also found in the exhaust of the natural gas-fueled heavy-duty vehicles. The 

HM had lower PM emissions that the NE, but more than 10 times the level of these two PAH 

compounds. The more active catalyst on the NE may have been instrumental in producing 

the lower levels of these PAHs in the exhaust.
198 

10.0 HEAVY-DUTY DIESEL VEHICLE TESTS

10.1 Vehicle Selection and Description

Vehicle selection was made in collaboration with the CLOSE Project Management Team. 

SwRI identified potential candidate vehicles for testing and made vehicle recommendations to 

the CLOSE Project Management Team. We then waited for technical approval prior to 

procuring the test vehicles. One vehicle from each of the following categories was recruited:

10.1.1 Heavy-Duty Diesel Vehicle Selection Criteria

• Normal-emitting diesel vehicle: This heavy-duty vehicle was to be equipped with a

diesel engine having an advertised displacement of at least 7.2 liters and a minimum 

rated torque of 660 ft-lbs. The engine/vehicle was to be a model year 2002 or newer 

with fewer than 270,000 miles on the odometer. The vehicle was not to be equipped 

with a PM filter or trap, or an oxidation catalyst. It was expected that this vehicle 

would be a 60,000-lb capacity Class 8 on-highway tractor leased from a local agency. 

• High-emitter diesel vehicle: This heavy-duty vehicle was to be equipped with a 

diesel engine and to have an advertised displacement of at least 7.2 liters and a 

minimum rated torque of 660 ft-lbs. The engine/vehicle was to be a model year 1996 

or older and known to emit high levels of PM, have high lubrication oil consumption, 

and/or have visible smoke related to lubrication oil. It was thought that this vehicle 

would be solicited from a governmental fleet, and expected to be near the end of its 

useful life.

10.1.2 Heavy-Duty Diesel Vehicle Selection and Description 

As with the heavy-duty natural gas vehicles, SwRI spent months searching for heavyduty diesel vehicle candidates. SwRI was invited to inspect heavy-duty vehicles at City Public 

Service (CPS) Company, which is the electrical utility in the San Antonio area. These vehicles 

were used as construction and repair support vehicles for CPS and were up for sale. SwRI was 

informed that the vehicles had been released from service and could be used in the CLOSE 

program as heavy-duty diesel PM emission test vehicles. 

All the vehicles were 1993 to 1998 models. SwRI inspected six CPS vehicles and made a 

report to the CLOSE project sponsors with candidate recommendations. The report on the CPS 

vehicles is included in Appendix E. However, when we contacted City Public Service for more 

information on the vehicles, we found that they had all been sold. 

SwRI then found a contact at VIA Metropolitan Transit, which is San Antonio’s city bus 

company. We were informed that VIA would lease two candidate heavy-duty diesel buses to 

SwRI for the project. VIA offered SwRI a 1988 TMC bus with a DDC 6V/71N, V6 engine that 

had 736,871 miles as a candidate high PM emissions vehicle.

 The CLOSE sponsors rejected the first candidate heavy-duty diesel bus with high PM 

emissions because its two-stroke DDC engine was deemed to be of too old a design. We 
199 

requested that VIA search for more high PM emission diesel buses. We visited VIA in order to

observe three candidate high PM emission buses. VIA had not found any buses with smoky 

exhausts. The HM candidates were chosen by VIA because they all had high blowby rates. 

Because blowby is caused by poor piston ring seals, we expected that these vehicles would also 

allow more oil past the rings into the combustion chamber and exhaust. 

SwRI went to VIA’s maintenance yard and observed three candidate high PM buses. 

None of the buses were observed to have high smoke emissions. The second candidate high PM 

emissions bus we chose (Bus #842) had some light, white smoke during acceleration under load, 

and slight smoke at idle. This bus was already idling upon SwRI’s arrival at VIA, so we did not 

observe a cold engine start. There was no smoke visible during a hot-start of #842. The other 

two buses had less smoke than #842. 

Information regarding the second candidate high PM emissions diesel bus was furnished 

to the CLOSE sponsors along with information on a newer bus in good working order that was 

of the same make and model as the candidate high PM emitter. The CLOSE participants 

approved both VIA heavy-duty diesel buses as candidates for testing. 

SwRI and VIA signed an agreement to lease (at no cost) the two approved diesel buses 

for heavy-duty emissions testing. After testing the first low-PM emissions diesel bus, we asked 

VIA to prepare the second candidate high PM emissions bus (#842), but when they started it the 

engine failed. VIA found another bus (#839) for the project that had high blowby emissions like 

bus #842. Bus #839 is the same make and model as bus #842, and is the same make and model 

as the first low PM emitter (#946) we tested. Information regarding the third candidate diesel 

high PM emissions bus #839 was furnished to the CLOSE sponsors. The CLOSE Project 

sponsors approved the use of bus #839 as a high mileage PM emitter. Table 92 describes the two 

heavy-duty diesel buses selected for emissions testing.

TABLE 92. DESCRIPTION OF HEAVY-DUTY DIESEL BUSES

Normal Emitter High Mileage

Bus Number 946 839

Year 2001 2001

Make NABI NABI

Model 40 LFW - 05 40 LFW - 05

Mileage 461,403 569,240

VIN # 1N90400521A140336 1N9040051YA140614

License # 814-486 806-354

Engine 2001 Cummins 2001 Cummins

Engine Model CUM 8.3 ISC CUM 8.3 ISC

Engine Displacement 8.3L, 506 ci 8.3L, 506 ci

Engine oil spec. 15W-40 15W-40

Oil consumption, miles/quart 971 145
200 

10.1.3 Gaseous and PM Emissions Check-out Tests

When the low-PM emission heavy duty bus #942 was delivered, its emission rate 

repeatability was assessed over three hot-start HDDC cycles before changing its oil or fuel. 

Table 93 shows a statistical summary of the three replicate tests performed with bus #942. 

Repeatability of all emission rates was very good with a maximum covariance of 5 percent for 

hydrocarbons. The CLOSE Project sponsors accepted bus #942 for continued testing. 

TABLE 93. RESULTS OF THREE REPEATABILITY CHECK EMISSION TESTS 

PERFORMED WITH THE HEAVY-DUTY NORMAL PM EMITTING DIESEL BUS AS 

RECEIVED

(No Statistical Analyses Were Performed On These Data)

Emissions Average Standard Deviation Covariance 

HC, g/mile 0.59 0.03 5%

CO, g/mile 5.87 0.07 1%

NOX, g/mile 16.69 0.10 1% 

PM, g/mile 0.764 0.02 3% 

Fuel Economy, lb/mile 1.47 0.04 3%

These tests are not part of the particle characterization tests.

Tests were performed at a nominal 72°F, with commercial fuel and lubricant as received.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the 

number of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of 

comparisons across different temperatures, fuels or lubricants cannot be rigorously verified.

Before starting emissions tests for record and before changing its oil or fuel, SwRI also 

performed an emissions repeatability assessment with bus #839, the candidate high blowby and 

higher mileage diesel bus from VIA. Emissions were measured over three hot-start HDDC 

cycles. Table 94 shows a statistical summary of the three replicate tests performed with bus 

#839. Repeatability of all emission rates was also very good with a maximum emission rate 

covariance of 4 percent with CO emissions, and #839 was approved for further tests. Note that 

the PM emission rates from the high-mileage diesel bus are less than from the normal emitter.
201 

TABLE 94. RESULTS OF THREE REPEATABILITY CHECK EMISSION TESTS 

PERFORMED WITH THE HEAVY-DUTY HIGH-MILEAGE DIESEL BUS AS RECEIVED

(No Statistical Analyses Were Performed On These Data)

Emissions Average Standard Deviation Covariance

HC, g/mile 0.65 0.014 2%

CO, g/mile 5.96 0.250 4% 

NOX, g/mile 15.27 0.17 1% 

PM, g/mile 0.696 0.01 1%

Fuel Economy, lb/mile 1.57 0.01 0.5% 

These tests are not part of the particulate characterization tests.

Tests were performed at a nominal 72°F, with commercial fuel and lubricant as received.

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, where n is the 

number of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the statistical significance of 

comparisons across different temperatures, fuels or lubricants cannot be rigorously verified.

Because the HD natural gas and HD diesel vehicles did not exhibit higher PM emissions, 

they are designated as high mileage or HM.

10.2 Lubricants

The heavy-duty vehicles were tested with both fresh and aged lubricants. Their 

description and the supplier’s analyses are included in Section 5.1 in Tables 3 and 7. The drain 

and fill procedure is described in Section 5.1. Degreening of the lubricants was accomplished by 

operating the heavy-duty vehicles for 150 miles on the road or on the chassis dynamometer. Oil 

samples include the fresh and aged oils as received, and one oil sample each taken after 

completion of all tests on fresh and then aged oils from the normal- and high-mileage emitter. 

For example, the normal emitter was operated over multiple emission tests with fresh oil and a 

sample was taken from the crankcase drain oil, and then the normal emitter was operated over 

multiple emissions tests with aged oil and a sample was taken from the crankcase drain oil. Thus 

two oil samples were taken from the normal-emitter (fresh and aged oil), and two oil samples

were taken from the high-mileage emitter.

10.3 Fuels

Fuel systems on all vehicles were flushed with the test fuels prior to the initiation of 

testing. The heavy-duty diesel vehicles were fueled directly from an underground tank dedicated 

to the project. Analyses results for the TxLED diesel used for heavy-duty tests are included in 

Section 5.2.3.

10.4 Emission Test Procedures

This is a pilot study of exhaust emissions effects from the use of different fuels and 

lubricants with some tests conducted at different temperatures. It is important to note that the 

scope of work in this study is limited to short-term effects on emissions when a fuel or lubricant 

was changed. The fuels and lubricants used in this study could have long-term effects on 

emissions which were not measured.
202 

10.4.1 Driving Cycle

 The heavy-duty diesel vehicles were operated over the same test cycle as described in 

Section 9.4.1 for the natural gas vehicles. 

• Normal-Emitting Diesel Vehicle: With SwRI’s single-dilution sampling system, 

sufficient sample was collected over replicate cold- and hot-start HDDCs totaling 

approximately 20 miles. Thus a total of 8 HDDCs were performed in order to collect 

all 4 PM samples (2 HCCDs per sample × 2 oils × 2 replicate samples per oil). One 

additional cold- and hot-start HDDC was run for the DDP particle number and size 

determination.

• High-Mileage Diesel Vehicle: In order to parallel the testing of the normal-emitting 

diesel vehicle, SwRI tested this vehicle over the same number of replicate cold- and 

hot-start HDDCs as the normal emitter.

10.4.2 Chassis Dynamometer

The same dynamometer was used for testing the diesel buses as the natural gas buses. It 

is described in Section 9.4.2. 

10.5 Heavy-Duty Diesel Vehicles Emission Test Results

10.5.1 Regulated Gaseous and PM Emissions

Average results from both of the heavy-duty diesel vehicles are shown in Table 95. 

Average regulated gaseous emissions, PM emissions, and fuel consumption rates while operating 

the vehicles with fresh and aged oil are included. Standard deviations and covariances of the 

replicate tests are also provided (each replicate being comprised of one cold start and one hot 

start HDDC tests). All heavy-duty emission tests were conducted at a nominal 72oF ambient 

temperature. Repeatability of the emissions from the replicate tests was good. Hydrocarbon 

rates measured from the normal emitter (NE) bus on aged oil showed the greatest variability 

between the two replicate tests with a covariance of 15 percent. NOX emissions from the NE also 

exhibited higher variability with a covariance of 11 percent on fresh oil. In addition, 

hydrocarbon emissions from the high mileage (HM) bus with high blowby on aged oil showed a 

covariance of 11 percent, but all other emission rates exhibited lower variability with covariances 

below 10 percent. 

10.5.1.1 Discussion of Regulated Emissions Results

 Figures 91 through 95 display the emission tests results shown in Table 95. Note that 

long range precision was not thoroughly explored in the test design. Thus, statistical significance 

of comparisons across different temperatures, fuels, or lubricants cannot be rigorously verified. 

Hydrocarbon emissions from both heavy-duty diesel buses are shown in Figure 91. The highmileage high blowby bus averaged higher HC emissions than the low emitter but the variability 

was such that the standard deviations of the averages overlapped. HC emissions on aged oil 

were also higher than with fresh oil, but again, variability was high and the standard deviations 

overlapped. 
203 

TABLE 95. AVERAGE REGULATED EMISSIONS FROM HEAVY-DUTY

DIESEL VEHICLES

(No Statistical Analyses Were Performed On These Data)

72o F - Average of Duplicate Testsa

Normal Emitter High Mileage

Fresh Oil Aged Oil Fresh Oil Aged Oil

Average

Standard 

Deviation

Coefficient 

of 

Variation Average

Standard 

Deviation

Coefficient 

of 

Variation Average

Standard 

Deviation

Coefficient 

of 

Variation Average

Standard 

Deviation

Coefficient 

of 

Variation

HC, g/mile 0.61 0.05 8% 0.65 0.10 15% 0.66 0.03 4% 0.71 0.08 11% 

CO, g/mile 6.50 0.44 7% 6.20 0.36 6% 5.41 0.42 8% 5.49 0.11 2% 

NOx, g/mile 17.65 1.93 11% 19.97 0.40 2% 18.20 0.72 4% 19.07 0.57 3% 

PM, g/mileb 0.86 0.06 7% 0.78 0.02 2% 0.66 0.02 3% 0.64 0.01 1% 

Fuel Usage, 

lb/mile 1.58 0.06 4% 1.59 0.04 3% 1.65 0.01 1% 1.68 0.02 1% 

a Each replicate test consisted of one cold HDDC cycle and one hot HDDC cycle. b PM as determined from phase-by-phase filter samples collected during each of two duplicate tests. 

Note: Standard deviations reflect only short term variability within each group of successive UDCs (standard deviation, σn-1, 

where n is the number of replicate UDC tests). Longer range precision was not rigorously explored in the test design. Thus, the 

statistical significance of comparisons across different temperatures, fuels or lubricants cannot be rigorously verified.

 Figure 92 shows the carbon monoxide emissions from the heavy-duty diesel tests. CO 

emissions were lower from the high-mileage bus, but there was no trend in CO emissions 

comparing fresh to aged lubricant tests. Figure 93 shows that oxides of nitrogen emissions from 

both diesel buses were very similar, and it appears that aged oil tests had higher average NOX

emissions than fresh oil tests, although there is some overlap of the standard deviation around the 

mean. Figure 94 shows the fuel usage in pound per mile units from the heavy-duty diesel buses, 

and the normal PM emitter exhibited better fuel economy than the high mileage diesel bus. 

There was no trend in fuel usage comparing fresh to aged oil tests.

PM emissions from the heavy-duty diesel tests are shown in Figure 95. The high-mileage 

high blowby diesel bus had lower PM emissions than the vehicle designated as the normal PM 

emitter. This result was expected since the repeatability tests had already shown the same data. 

From both buses, operation on aged oil produced lower PM emissions than on fresh oil. PM

characterization results are presented in the next sections. 

FIGURE 91. HYDROCARBON EMISSION RATES FROM THE NORMAL PM EMITTER 

AND HIGH MILEAGE DIESEL BUSES

(No Statistical Analyses Were Performed On These Data) 

0.61 0.65 0.66 0.71

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

NE-F-D-72 NE-A-D-72 HE-F-D-72 HE-A-D-72

HC, g/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL
204 

FIGURE 92. CARBON MONOXIDE EMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE DIESEL BUSES

(No Statistical Analyses Were Performed On These Data)

FIGURE 93. OXIDES OF NITROGENEMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE DIESEL BUSES

(No Statistical Analyses Were Performed On These Data)

6.50 6.20 5.41 5.49

0

1

2

3

4

5

6

7

8

9

NE-F-D-72 NE-A-D-72 HE-F-D-72 HE-A-D-72

CO, g/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL

17.6 20.0 18.2 19.1

0

5

10

15

20

25

NE-F-D-72 NE-A-D-72 HE-F-D-72 HE-A-D-72

NOx, g/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL
205 

FIGURE 94. FUEL CONSUMPTION OF THE NORMAL PM EMITTER AND HIGH 

MILEAGE DIESEL BUSES

(No Statistical Analyses Were Performed On These Data)

FIGURE 95. PARTICULATE MATTER EMISSION RATES FROM THE NORMAL PM 

EMITTER AND HIGH MILEAGE DIESEL BUSES

(No Statistical Analyses Were Performed On These Data)

1.58 1.59 1.65 1.68

0.0

0.5

1.0

1.5

2.0

NE-F-D-72 NE-A-D-72 HE-F-D-72 HE-A-D-72

FU, lb/mile

 

 

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL

0.86 0.78 0.66 0.64

0.0

0.2

0.4

0.6

0.8

1.0

1.2

NE-F-D-72 NE-A-D-72 HE-F-D-72 HE-A-D-72

PM, g/mile

NORMAL PM EMITTER HIGH MILEAGE

FRESH OIL AGED OIL FRESH OIL AGED OIL
206 

10.5.2 PM and SVOC Analyses

PM from the heavy-duty diesel vehicle tests was analyzed for elements, semi-volatile 

organic compounds (SVOC), elemental and organic compounds (EC/OC), sulfates, and soluble 

organic fraction (SOF) at DRI. In the following PM characterization subsections, Tables 96 

through 103 present the results of these characterizations along with analyses of heavy-duty fuel 

and lubricants. PM analysis data shown in Tables 96 through 103 are the averages of the 

replicate tests performed in each configuration. 

The spreadsheet of light-duty PM and SVOC analyses results which was devised by 

Dr. Fujita to investigate the light-duty PM characterization results was used as a template for the 

heavy-duty PM characterization results. The spreadsheet includes the results from the individual 

tests, and is posted at an SwRI ftp site. Dr. Lawrence Smith of SwRI used the spreadsheet data 

to identify elements and compounds of interest in the apportionment study presented in Section 

10.6. 

10.5.2.1 X-Ray Fluorescence (XRF)

 Particulate matter sampled from the heavy-duty diesel tests was analyzed by DRI for 

elements by XRF. Table 96 shows the average results in μg/mile of the replicate tests performed 

in each configuration. In addition, Table 96 presents the results of the lubricant analyses for 

elements by XRF. The configurations are identified in the top rows of the table, and elements 

measured are shown in the left column.

10.5.2.2 Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Analysis

PM sampled from the heavy-duty diesel tests was analyzed by DRI for eighteen elements 

by ICP-MS. Table 97 shows the average results from PM in μg/mile of the replicate tests 

performed in each configuration. Table 97 also shows the results of elemental analysis of the 

lubricants and diesel fuel performed at EAI Inc. EAI measured five more elements than DRI 

measured in the particulate matter. Elements found in lubricants and fuel are presented in 

nanogram (ng) per gram of oil units. The configurations are identified in the top rows of the 

table, and elements measured are shown in the left column. 

10.5.2.3 Polycyclic Aromatic Hydrocarbons

 PM and SVOCs sampled from the heavy-duty diesel tests were analyzed by DRI for 

polycyclic aromatic hydrocarbons (PAH). Table 98 shows the average results from the exhaust

in μg/mile of the replicate tests performed in each configuration. Table 98 also shows the results 

of lubricant analyses for PAHs in μg/gram units. Table 28 shows the codes for the PAH species 

in Table 98. 
207 

TABLE 96. AVERAGE HEAVY-DUTY DIESEL PM ELEMENTAL ANALYSIS BY XRF

(No Statistical Analyses Were Performed On These Data)

Elemental Emission Rates, μg/mi Lubricant Elements, μg/gram 

Test Number

HD-NE-FD-72 HD-NE-AD-72 HD-HM-F-D72 HD-HM-AD-72 HD-NE-FD-72 HD-NE-AD-72 HD-HM-F-D72 HD-HM-AD-72 

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel Diesel

Temp, oF 72 72 72 72 72 72 72 72

Na 0 16 1478 0 0 0 0 0

Mg 0 0 658 0 0 0 0 0

Al 25 48 287 128 0 0 0 0 

Si 211 68 379 51 0 0 0 0 

P 2504 955 2819 1200 181 118 147 153

S 1396 725 1851 876 2948 3049 2930 3130

Cl 647 260 518 238 0 0 0 0 

K 48 55 46 4 0 0 0 0

Ca 5064 2870 5045 2397 2601 2701 2646 2713

Sc 0 0 0 0 0 0 0 0 

Ti 13 14 27 7 0 0 0 0

Va 3 0 3 1 0 0 0 0

Cr 50 59 46 10 0 4 3 4 

Mn 34 24 1 30 0 1 0 1 

Fe 3860 2203 2107 982 2 59 5 62

Co 0 3 0 0 0 0 0 0

Ni 8 31 3 1 0 0 0 0 

Cu 130 77 168 81 0 0 0 0

Zn 3174 1414 3681 1454 1495 1461 1495 1475

Ga 0 0 0 0 0 0 0 0 

As 0 0 0 0 0 0 0 0

Se 0 0 0 0 0 0 0 0

Br 0 0 0 0 0 0 0 0 

Rb 0 0 0 0 0 0 0 0 

Sr 4 2 5 6 0 0 0 0

Yt 0 0 3 0 0 0 0 0

Zr 1 20 10 12 0 0 0 0 

Nb 0 1 7 3 0 0 0 0

Mo 59 32 85 1 0 1 0 1

Pd 0 10 0 0 0 0 0 0 

Ag 6 7 0 0 0 0 0 0

Cd 0 1 0 0 0 0 0 0

In 4 5 0 0 0 0 0 0 

Sn 0 0 0 0 0 0 0 0 

Sb 0 0 13 11 0 0 0 0

Cs 0 0 0 0 0 0 0 0

Ba 0 0 0 20 0 0 0 0 

La 9 0 0 15 0 0 0 0

Ce 34 6 17 44 0 0 0 0
208 

TABLE 96 (CONT’D). AVERAGE HEAVY-DUTY DIESEL PM ELEMENTAL 

ANALYSIS BY XRF

(No Statistical Analyses Were Performed On These Data)

Elemental Emission Rates, μg/mi Lubricant Elements, μg/gram 

Test Number

HD-NE-FD-72HD-NE-AD-72HD-HM-F-D72HD-HM-AD-72HD-NE-FD-72HD-NE-AD-72HD-HM-F-D72HD-HM-AD-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel Diesel

Temp, oF 72 72 72 72 72 72 72 72

Sm 38 62 87 81 0 0 0 0

Eu 0 0 81 0 0 0 0 0

Tb 0 0 72 0 0 0 0 0 

Hf 0 0 0 0 0 0 0 0

Ta 0 0 0 11 0 0 0 0

Wo 0 32 0 0 0 0 0 0 

Ir 0 0 0 0 0 0 0 0

Au 0 0 0 0 0 0 0 0

Hg 0 0 1 0 0 0 0 0 

Tl 0 1 0 1 0 0 0 0 

Pb 0 17 2 18 0 5 0 5
209 

TABLE 97. RESULTS OF HEAVY-DUTY DIESEL PM, LUBRICANTS, AND FUEL 

ELEMENTAL ANALYSIS BY ICP-MS

(No Statistical Analyses Were Performed On These Data)

TEST 

NUMBER 

AVERAGE PARTICULATE ELEMENTS, μg/mile LUBRICANT AND FUEL ELEMENTS, ng/gram

HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72 HD-NE-F-D-72 HD-NE-A-D-72 EM-7006-F 

Emitter Normal Normal High Mileage High Mileage Normal Normal Both 

Oil Fresh Aged Fresh Aged Fresh Aged Both 

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel 

Temp 72 72 72 72 72 72 72

Mg 685.21 120.97 1031.60 161.23 9744 7593 <LODa

Al 673.32 0.00 0.00 801.60 1583 10068 <LOD 

Ca 4360.75 4007.91 1316.24 1452.06 2283753 2307237 <LOD 

Va 0.07 0.01 0.00 0.18 22 24 <LOD 

Cr 29.99 13.38 31.10 45.31 51 2021 <LOD 

Mn 19.13 19.15 35.73 21.95 84 690 <LOD 

Fe 2447.64 2312.70 1238.99 1069.12 1727 41393 14

Ni 13.21 4.69 27.33 32.46 109 593 <LOD 

Cu 140.10 87.03 46.65 108.00 92 4546 <LOD 

Zn 2420.67 1880.71 1281.79 2177.55 1295948 1213750 <LOD 

Mo 40.40 23.01 7.74 39.70 387 1340 <LOD 

Ag 13.66 10.06 2.19 7.98 <LOD 20 <LOD 

Cd 0.00 0.04 0.04 0.01 0 0 0 

Sn 0.00 0.50 1.11 0.87 0 0 0 

Ba 8.61 3.17 1.62 2.01 21 1675 <LOD 

Ce 38.60 19.25 3.64 155.45 0 0 0 

Hg 0.00 0.00 0.00 0.00 0 0 0 

Pb 4.61 4.75 5.71 7.35 65 4870 <LOD 

W NMb NM NM NM <LOD 16 <LOD 

P NM NM NM NM 1100160 956503 <LOD 

S NM NM NM NM 3842501 3755101 7775

Ti NM NM NM NM 40 77 <LOD 

Sr NM NM NM NM 748 830 <LOD 

a Less than Level of Detection

b Not measured 
210 

TABLE 98. HEAVY-DUTY DIESEL AVERAGE POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Exhaust PAHs, μg/mile Lubricant PAHs, μg/gram

Test

Number HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72 HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel Diesel

Temp, °F 72 72 72 72 72 72 72 72

Mediaa F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correctionb Yes Yes Yes Yes NA NA NA NA

naphth 62.85 123.66 196.89 83.47 28.11 34.98 27.90 28.25

quinoline 16.96 0.00 0.00 0.00 0.00 0.00 0.00 0.00

mnaph2 82.11 25.88 124.96 109.25 25.69 31.69 21.58 26.39

mnaph1 93.49 71.99 115.74 111.09 12.26 15.89 11.24 13.37

biphen 59.53 36.65 20.95 53.98 1.20 2.11 1.25 2.04

m_2bph 246.64 0.00 0.00 0.00 0.00 0.00 0.00 0.87

dmn267 114.55 53.39 56.17 100.59 6.13 10.56 6.71 7.31

dm1367 233.42 115.34 151.63 228.94 10.49 17.53 9.09 14.28

d14523 69.16 32.55 23.18 63.51 2.74 4.38 1.48 2.65

enap12 105.26 12.64 1.72 18.63 1.93 2.82 2.26 2.99

acnapy 14.24 21.28 15.98 18.03 0.00 0.00 0.00 0.00

dmn12 9.71 19.67 4.07 10.62 0.39 1.02 0.16 0.80

dmn18 1.53 0.00 0.21 0.00 0.00 0.00 0.00 0.00

acnape 0.00 7.36 0.00 0.00 0.00 0.12 0.00 0.00

m_3bph 244.87 0.00 0.00 0.00 2.08 3.60 2.65 4.77

m_4bph 99.78 0.00 0.00 0.00 0.81 0.98 0.27 0.91

dbzfur 4.49 11.35 5.88 8.65 0.00 0.08 0.08 0.15

em_12n 9.61 21.31 13.17 20.98 0.54 1.13 0.23 0.45

tmi235n 32.18 25.49 21.48 55.94 3.28 9.90 0.55 7.01

btmnap 55.50 19.15 28.20 51.28 3.12 11.58 2.85 7.65

atmnap 177.41 21.65 30.10 41.13 1.62 9.12 1.05 6.32

ctmnap 60.07 28.41 35.82 64.48 3.78 9.94 3.43 7.76

em_21n 2.88 1.71 0.00 0.00 0.00 0.08 0.00 0.04

etmnap 30.16 17.58 21.03 34.42 1.66 6.61 1.29 6.02

tm245n 15.86 4.17 4.21 4.84 0.15 0.94 0.39 0.30

ftmnap 24.51 11.64 15.75 29.28 2.01 6.38 1.60 3.94

fluore 16.42 13.99 7.72 6.22 0.66 3.68 1.09 1.06

tm145n 3.83 3.07 2.39 4.33 0.54 0.39 0.23 0.15

jtmnap 17.11 17.15 1.49 8.41 0.27 3.91 0.16 4.01
211 

TABLE 98 (CONT'D). HEAVY-DUTY DIESEL AVERAGE POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST

AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Exhaust PAHs, μg/mile Lubricant PAHs, μg/gram

Test

Number HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72 HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel Diesel

Temp, °F 72 72 72 72 72 72 72 72

Mediaa F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correctionb Yes Yes Yes Yes NA NA NA NA

a_mfluo 4.00 11.29 10.60 5.91 0.77 2.66 0.90 4.17

b_mfluo 0.72 0.97 2.40 2.26 0.15 0.55 0.00 1.33

m_1fluo 15.07 14.06 25.95 29.62 1.16 0.70 0.31 5.00

fl9one 50.56 48.93 86.81 77.99 0.08 0.35 0.08 0.64

phenan 145.30 104.45 183.64 181.18 1.54 8.30 0.70 8.33

anthra 7.03 7.48 12.96 15.20 0.31 1.76 0.12 1.48

xanone 0.78 0.54 0.00 0.00 0.08 7.79 0.00 8.48

acquone 6.77 0.00 0.00 0.00 0.00 0.00 0.00 0.00

m_2phen 30.09 27.43 42.25 56.18 1.04 10.45 0.78 11.36

m_3phen 35.23 32.07 48.91 62.06 1.35 14.79 0.43 13.48

pnapone 0.72 9.17 1.26 1.15 0.42 2.31 0.35 1.67

m_2anth 1.56 1.18 2.70 3.40 0.42 0.67 0.43 2.54

m_45phen 7.63 4.07 10.43 10.56 0.66 2.31 0.43 1.14

m_9phen 19.21 18.21 30.94 38.89 0.54 8.30 1.09 7.69

mpht_1 8.04 18.37 1.63 0.08 0.62 7.51 0.98 3.14

anthron 0.00 0.00 2.52 0.00 0.00 15.30 1.44 16.24

m_9ant 0.62 4.34 1.07 1.63 0.46 0.70 0.23 0.64

nap2phen 7.50 5.36 13.34 13.18 0.27 0.16 0.23 1.17

anrquone 0.72 2.07 0.00 0.00 0.27 2.00 0.04 0.19

a_dmph 12.76 0.00 15.65 26.70 0.35 6.89 0.55 5.72

b_dmph 4.56 14.07 7.19 9.88 0.50 3.48 0.23 3.98

dm17ph 27.61 7.23 12.92 17.01 0.46 7.94 0.16 8.56

dm36ph 4.59 4.92 6.53 9.89 0.31 4.58 0.31 3.82

d_dmph 29.62 7.58 12.85 16.83 0.50 4.97 0.39 4.58

e_dmph 21.06 2.40 2.92 3.60 0.54 4.46 0.08 3.67

c_dmph 31.01 16.00 27.68 37.74 0.89 12.95 0.78 13.29

fluora 25.10 16.46 31.64 25.83 0.15 0.82 0.47 0.34

pyrene 27.26 21.18 40.39 39.95 0.81 5.87 0.27 6.93

antal9 0.00 0.00 1.07 0.00 1.70 3.87 1.44 2.39
212 

TABLE 98 (CONT'D). HEAVY-DUTY DIESEL AVERAGE POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST

AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Exhaust PAHs, μg/mile Lubricant PAHs, μg/gram

Test

Number HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72 HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel Diesel

Temp, °F 72 72 72 72 72 72 72 72

Mediaa F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correctionb Yes Yes Yes Yes NA NA NA NA

retene 0.00 0.00 0.76 1.70 0.23 0.08 0.20 0.15

bafluo 1.98 0.11 3.32 3.78 1.50 1.06 1.13 2.57

bbfluo 0.41 0.00 0.10 0.22 0.62 0.47 1.17 1.44

bmpyfl 0.00 1.79 0.00 0.00 1.70 1.25 1.76 2.99

c1mflpy 0.00 1.72 0.00 0.00 0.00 0.98 0.27 0.64

m_13fl 5.59 1.60 8.23 9.37 1.70 1.21 1.29 1.44

m_4pyr 6.46 3.80 3.94 8.99 0.81 3.05 0.66 6.06

cmpyfl 0.00 0.34 0.00 0.00 1.12 0.82 2.03 2.54

dmpyfl 0.00 4.51 0.00 0.00 0.54 2.74 0.47 6.25

m_1pyr 0.00 1.01 0.00 0.18 0.77 2.23 0.55 3.37

bntiop 0.43 0.00 0.22 0.06 0.77 0.39 0.74 0.53

bzcphen 0.59 0.38 0.89 0.79 0.23 0.90 0.35 0.30

bghifl 4.90 3.05 10.40 9.53 0.00 0.63 0.31 0.27

phant9 0.30 0.25 0.21 0.19 0.12 0.35 0.16 0.11

cp_cdpyr 4.09 0.14 1.37 1.39 0.00 0.67 0.23 0.49

baanth 0.94 1.36 1.92 2.54 0.46 0.67 0.55 0.38

chr_tr 4.45 0.69 0.00 0.00 0.31 0.90 0.55 0.95

bzanthr 2.92 1.41 4.58 5.31 0.77 0.90 1.76 1.44

baa7_12 0.00 0.00 0.23 0.58 0.93 1.17 6.67 2.35

m_3chr 0.00 0.00 0.29 0.09 0.00 0.51 0.43 0.23

chry56m 0.00 0.00 0.00 0.00 0.50 0.67 0.51 0.38

m_7baa 0.00 0.00 0.00 0.00 0.42 0.51 0.55 0.42

dmban712 0.44 0.00 23.90 16.56 0.50 0.23 0.23 0.72

bbjkfl 0.49 0.36 0.45 0.07 0.00 0.23 0.12 0.49

bafl 0.38 0.00 0.21 0.40 0.00 0.16 0.04 0.11

bepyrn 0.40 0.00 0.83 0.61 0.19 0.23 0.20 0.42

bapyrn 0.14 0.18 0.42 0.36 0.00 0.23 0.16 0.23

peryle 0.00 0.18 0.00 0.00 0.35 0.47 0.16 0.53
213 

TABLE 98 (CONT'D). HEAVY-DUTY DIESEL AVERAGE POLYCYCLIC AROMATIC HYDROCARBONS IN EXHAUST

AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

Exhaust PAHs, μg/mile Lubricant PAHs, μg/gram

Test

Number HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72 HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel Diesel

Temp, °F 72 72 72 72 72 72 72 72

Mediaa F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correctionb Yes Yes Yes Yes NA NA NA NA

m_7bpy 1.15 0.00 0.00 0.00 0.00 0.04 0.23 0.19

bpy910dih 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

incdfl 0.07 0.00 0.01 0.03 0.35 1.37 1.60 0.72

dbahacr 0.00 0.00 0.00 0.00 0.00 0.59 0.51 0.23

dbajacr 0.00 0.00 0.00 0.00 0.00 0.43 0.59 0.49

in123pyr 0.00 0.00 0.01 0.00 0.85 0.74 0.74 0.42

dbahacan 0.00 0.00 0.00 0.00 1.00 0.67 0.90 0.76

dbajan 0.00 0.00 0.00 0.00 0.66 0.27 0.90 0.23

bbchr 0.00 0.00 0.01 0.00 1.39 0.35 0.74 0.30

pic 0.00 0.00 0.00 0.00 0.00 1.25 3.12 1.36

bghipe 0.23 0.00 0.02 0.18 1.16 0.55 1.87 0.23

anthan 0.00 0.00 0.03 0.03 0.19 0.63 1.21 0.42

dbalpyr 0.00 0.00 0.00 0.00 0.35 0.00 0.23 0.72

corone 0.01 0.00 0.00 0.00 0.00 0.67 0.39 0.23

dbaepyr 0.02 0.00 0.00 0.00 0.00 0.00 0.35 0.15

dbaipyr 0.02 0.00 0.00 0.00 0.00 0.90 0.00 0.00

dbahpyr 0.00 0.00 0.02 0.00 0.00 0.78 0.00 0.23

dbbkfl 0.00 0.00 0.00 0.00 0.19 0.23 0.31 0.49

dbth 5.24 2.96 1.43 1.82 0.39 0.39 0.39 0.47 a Filter and XAD cartridge samples

b Test samples were corrected by subtracting a tunnel blank measurement
214 

10.5.2.4 Alkanes 

Exhaust samples from the heavy-duty diesel tests were analyzed by DRI for alkanes. 

Table 99 shows the average results in μg/mile of the replicate tests performed in each 

configuration. Table 30 shows the codes for the alkane species in Table 99. Table 99 also shows 

the results of lubricant analyses for alkanes in μg/gram units.

10.5.2.5 Hopanes and Steranes

 Exhaust samples from the heavy-duty diesel tests were analyzed by DRI for hopanes and 

steranes. Table 100 shows the average results in μg/mile of the replicate tests performed in each 

configuration. Table 33 shows the codes for the hopanes and steranes species in Table 100. 

Table 100 also shows the results of lubricant analyses for hopanes and steranes in μg/gram units. 

10.5.2.6 Particle-Phase Elemental and Organic Carbon 

 PM samples from the heavy-duty diesel tests were analyzed by DRI for elemental carbon 

and organic carbon (EC/OC). Table 101 shows the average results in mg/mile of the replicate 

tests performed in each configuration. The configurations are identified in the five left columns 

of the table, and EC/OC results are shown in the three right columns. In Table 101, EC is 

elemental carbon measured, OC is organic carbon, and TC is total carbon. 

10.5.2.7 Particle-Phase Sulfates

 PM samples from the heavy-duty diesel tests were analyzed by DRI for sulfates. Table 

102 shows the average results in μg/mile of the replicate tests performed in each configuration.

10.5.2.8 Particle-Phase Soluble Organic Fraction 

 PM samples from the heavy-duty diesel tests were analyzed by DRI for soluble organic 

fraction (SOF). Table 103 shows the average results for the normal emitter and high mileage, in 

percent SOF, of the replicate tests performed in each configuration. 
215 

TABLE 99. HEAVY-DUTY DIESEL AVERAGE ALKANES IN EXHAUST AND 

LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

EXHAUST ALKANES EMISSION RATES, μg/mile LUBRICANT ALKANES, μg/gram

TEST 

NUMBER

HD-NE-F-D72HD-NE-A-D72HD-HM-F-D72HD-HM-A-D72HD-NE-F-D72HD-NE-A-D72HD-HM-F-D72HD-HM-A-D72

Source Exhaust Exhaust Exhaust Exhaust Oil Oil Oil Oil

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel Diesel

Temp 72.0 72.0 72.0 72.0 72.0 72.0 72.0 72.0

Media F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction Yes Yes Yes Yes NA NA NA NA

dodec 2245.5 278.5 66.8 417.0 13.6 14.8 1.3 9.8

norfarn 1012.8 568.0 457.5 801.6 6.3 8.1 1.6 3.8

tridec 2190.1 1086.1 1168.5 1831.2 22.3 32.1 8.2 22.9

hpycyhx 218.6 83.4 108.6 206.3 1.0 3.2 0.4 1.9

farnes 524.8 381.4 296.9 536.6 4.8 10.1 2.2 9.7

tdec 2270.1 894.4 684.7 1550.0 35.9 67.4 17.7 57.6

ocycyhx 231.7 89.5 70.8 145.5 1.3 6.7 0.2 5.5

pentad 1488.4 771.8 736.0 1437.5 48.4 127.7 31.1 124.6

noycyhx 174.6 149.2 23.4 95.0 4.4 8.6 0.4 14.2

hexad 1030.9 689.0 504.9 1155.7 64.0 212.0 44.4 227.5

norprst 403.4 348.7 184.6 480.7 25.6 117.3 12.8 113.4

decyhx 77.6 73.6 30.2 79.4 2.8 10.4 1.1 20.0

heptad 837.1 535.7 380.6 905.4 102.3 380.6 98.2 376.6

heptdpris 648.5 461.8 345.7 817.5 44.8 152.4 24.8 167.8

dec1yhx 53.0 47.6 22.6 34.9 5.3 25.8 5.8 25.4

octad 534.1 578.6 370.7 579.8 60.5 368.4 52.6 385.6

phytan 274.6 250.5 184.3 288.4 36.5 203.2 29.4 203.6

dec2yhx 30.8 27.2 20.4 19.2 6.8 36.4 5.1 35.4

nonad 604.6 597.0 465.9 515.4 59.4 427.9 49.5 445.1

dec3yhx 17.8 12.4 11.9 15.8 8.6 21.1 8.3 25.1

eicosa 492.9 532.7 370.9 393.9 70.9 413.2 75.1 409.3

dec4yhx 12.9 15.2 6.1 8.0 18.1 57.3 10.5 43.3

heneic 268.4 303.2 224.7 240.9 66.0 371.2 44.8 404.6

dec5yhx 7.4 1.9 0.5 6.8 5.7 85.4 7.9 98.0

docosa 38.6 134.3 62.3 92.0 109.5 308.1 129.9 280.2

dec6yhx 0.0 0.9 0.5 0.0 12.1 45.8 11.6 15.3

tricosa 0.0 100.1 4.8 0.8 149.4 197.3 138.5 234.7

dec7yhx 1.7 39.9 12.9 28.6 16.6 144.5 39.0 165.6

tetcos 0.4 80.6 0.0 0.0 54.0 167.4 132.0 196.1

dec8yhx 34.1 0.5 91.4 81.7 29.8 22.3 19.4 31.5

pencos 0.0 81.8 0.0 0.0 241.6 122.4 92.9 294.9

hexcos 5.1 37.0 16.5 0.0 110.0 138.6 103.6 187.3

dec9yhx 0.6 6.9 6.3 0.0 3.9 12.0 20.5 26.4

hepcos 8.6 0.0 0.5 0.0 165.6 38.0 12.0 100.8

cyhxeic 0.1 4.4 0.1 3.0 23.3 147.8 21.3 81.3

octcos 0.0 0.0 9.1 0.0 55.1 57.4 55.1 55.1

noncos 5.2 0.2 8.2 0.0 44.5 10.7 63.8 58.0

cyhxhen 0.6 2.3 4.4 0.0 12.4 19.0 27.8 10.1

tricont 0.0 0.0 0.0 0.0 54.9 93.9 13.8 6.4

htricont 0.0 5.1 16.6 0.0 33.1 2.5 2.2 7.5

dtricont 0.0 3.5 10.9 0.0 13.8 3.8 6.4 18.6

ttricont 0.0 1.7 0.0 0.0 2.9 4.9 0.0 2.1

tetricont 0.0 1.1 0.0 0.0 28.8 13.8 15.3 9.7

ptricont 0.2 2.0 0.0 0.0 4.1 2.9 3.3 0.0

hxtricont 0.6 2.0 0.0 0.0 0.7 0.0 0.5 0.0

hptricont 0.0 0.0 0.6 0.0 4.3 6.0 4.1 1.7

otricont 0.2 0.0 0.0 0.0 1.0 1.8 3.7 1.7

ntricont 1.2 0.0 0.5 1.1 2.9 1.2 4.8 2.1

tecont 1.1 0.0 0.0 0.1 0.0 1.6 2.1 2.5

hxtric74 24.6 36.0 16.7 9.4 218.5 145.1 196.5 109.3

ucm 64923.7 28867.3 37983.3 48942.2 223690.1 243031.9 276126.3 243855.9
216 

TABLE 100. HEAVY-DUTY DIESEL AVERAGE HOPANES AND STERANES IN EXHAUST

AND LUBRICANTS

(No Statistical Analyses Were Performed On These Data)

PARTICULATE HOPANES AND STERANES EMISSION RATES, μg/mile LUBRICANT HOPANES AND STERANES, μg/gram

TEST 

NUMBER HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72 HD-NE-F-D-72 HD-NE-A-D-72 HD-HM-F-D-72 HD-HM-A-D-72

Emitter Normal Normal High Mileage High Mileage Normal Normal High Mileage High Mileage

Oil Fresh Aged Fresh Aged Fresh Aged Fresh Aged

Fuel Diesel Diesel Diesel Diesel Diesel Diesel Diesel Diesel

Temp, F° 72 72 72 72 72 72 72 72

Media F+XAD F+XAD F+XAD F+XAD Oil Oil Oil Oil

TB Correction Yes Yes Yes Yes NA NA NA NA

hop15 1.28 0.65 0.96 1.69 11.55 24.28 12.39 23.08

hop17 4.65 5.55 4.63 9.03 28.60 61.65 37.05 65.80

hop19 5.60 5.32 3.25 2.83 20.98 38.58 25.56 40.44

hop20 0.11 0.00 0.00 0.11 1.50 2.70 1.91 3.06

hop21 1.48 2.22 2.17 3.56 13.83 29.64 21.05 29.63

hop22 1.34 2.03 0.99 0.58 9.45 19.64 10.30 19.01

hop23 0.11 0.00 0.80 0.59 1.06 0.00 0.00 2.71

hop24 1.01 1.32 0.94 0.79 7.25 15.69 12.06 16.13

hop25 0.00 0.00 0.23 0.00 5.57 10.08 5.37 8.88

hop26 0.64 0.69 0.77 0.54 5.09 9.39 5.89 12.08

hop27 0.50 0.37 0.14 0.33 2.62 9.58 4.45 8.52

ster42 0.63 1.40 0.73 0.90 1.62 5.48 3.01 5.42

ster43 1.60 0.19 3.50 1.83 11.40 23.50 12.12 23.73

ster44 5.80 1.77 1.42 0.76 5.24 10.76 4.56 12.95

ster45_40 2.15 0.32 0.37 0.69 9.18 17.26 8.71 17.61

ster46 0.48 1.35 1.20 0.34 1.80 2.53 2.33 3.58

ster47 0.96 0.19 0.00 0.22 5.15 12.50 6.61 12.55

ster48_41 0.39 0.05 0.00 4.49 2.38 4.64 2.75 4.60

ster49 0.42 0.59 0.61 0.09 1.74 1.92 2.46 1.94

ster50 0.56 0.00 0.50 0.31 2.07 6.20 4.63 5.40

ster51 0.61 0.17 2.33 1.13 5.25 10.89 4.69 12.39

ster52 0.61 0.07 0.82 0.91 3.82 8.14 4.45 8.34

ster53 0.69 0.00 0.54 0.00 3.30 4.80 4.67 5.44

TABLE 101. HEAVY-DUTY DIESEL AVERAGE ELEMENTAL CARBON AND ORGANIC 

CARBON RATE

(No Statistical Analyses Were Performed On These Data)

TEST NUMBER EMITTER OIL FUEL TEMP EC OC TC

HD-NE-F-D-72 Normal Fresh Diesel 72 828 123 952

HD-NE-A-D-72 Normal Aged Diesel 72 712 132 844

HD-HE-F-D-72 High Mileage Fresh Diesel 72 569 122 691

HD-HE-A-D-72 High Mileage Aged Diesel 72 584 131 715

CARBON EMISSION RATES, mg/mile
217 

TABLE 102. AVERAGE SULFATE EMISSIONS FROM HEAVY-DUTY DIESEL VEHICLES

(No Statistical Analyses Were Performed On These Data)

TEST NUMBER Vehicle Oil Fuel Temp

Average Sulfate, 

μg/mile

HD-NE-F-D-72 Normal Emitter Fresh Diesel 72oF 1685

HD-NE-A-D-72 Normal Emitter Aged Diesel 72oF 1181 

HD-HM-F-D-72 High Mileage Fresh Diesel 72oF 2987 

HD-HM-A-D-72 High Mileage Aged Diesel 72oF 456 

TABLE 103. HEAVY-DUTY DIESEL VEHICLE AVERAGE SOLUBLE ORGANIC 

FRACTION

(No Statistical Analyses Were Performed On These Data)

TEST NAME Lubricant Vehicle Fuel

Ambient 

Temperature, oF

Average 

SOF, %

HD-NE-F-D-72 Fresh Normal Emitter Diesel 72 14%

HD-NE-A-D-72 Aged Normal Emitter Diesel 20 13%

HD-HM-F-D-72 Fresh High Mileage Diesel 72 18%

HD-HM-A-D-72 Aged High Mileage Diesel 20 16%

10.5.2.9 Particle Number and Size Distribution Emission Test Results

 Figures 96 and 97 show the exhaust PN concentration for the heavy-duty diesel normal 

emitter (HD-D-NE). The data are shown for the fresh and aged oil at 72°F. The data are plotted 

as an average concentration for one cold-start and one subsequent hot-start of the HD UDDS. 

The exhaust PN concentration ranged from about 12x106 part./cm3 to 18x106 part./cm3. This is 

comparable to the MD-NE and the HD-NG-NE, but the PN composition and size distribution are 

different from those emitted from the HD-NG-NE and similar to those emitted from MD-NE, as 

shown later in this section. No notable differences were observed between cold-start and hotstart and fresh and aged oils. Figures 98 and 99 show the percent ratio of solid and volatile PN 

concentration to total PN concentration. Seventy to ninety percent of the number of particles 

emitted from the HD-D-NE were solid in nature. This is much different from the HD-NG-NE 

that was dominated by volatile particles. It is also slightly different from the MD-NE that had 

more volatile PN than that observed with the HD-D-NE. While total PN emission is similar 

between HD-D-NE and HD-NG-NE, the solid or soot PN emission from the HD-D-NE is much 

higher than that observed with HD-NG-NE. This suggests that fuel is the major contributor of 

PN in HD-D, while lube oil is the major contributor of PN in HD-NG. Even if the oil 

consumption is similar between the two vehicle types, the absence of soot or solid particle 

surface area in the HD-NG vehicles promotes sulfuric acid and hydrocarbon particle nucleation 

and growth. This phenomenon was observed and discussed in previous work (CRC Project E-66 

Phase 1 & 2, www.crcao.com). Essentially, the presence of soot during dilution and cooling acts 

as a surface area available for adsorption/condensation of volatile material. In the absence of 

such surface area, the path for particle nucleation is enhanced. Also, the same phenomenon can 

explain the lack of PN emissions from the HD-D vehicles between fresh and aged oil, compared 
218 

to HD-NG vehicles. The soot present in diesel exhaust dominates PN emission, and changes in 

lube oil volatility or properties have a minor influence on PN. 

FIGURE 96. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (DIESEL, 

NORMAL EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 97. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (DIESEL, 

NORMAL EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)
219 

FIGURE 98. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(DIESEL, NORMAL EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 99. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL PARTICLES

(DIESEL, NORMAL EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)
220 

 Figures 100 and 101 show the exhaust PN concentration for the HD-D high mileage 

(HM) vehicle. The exhaust PN concentration ranged from 10x106 part./cm3 to 16x106 part./cm3. 

This concentration range is similar to that of the HD-D-NE and the MD-NE and MD-HE, but 

much lower than that of the LD-HE and the HD-NG-HM. This further demonstrates that when 

soot dominates PN emission, lube oil contribution to PN is minimized. It is interesting to note 

that among the vehicles tested, LD-HE and HD-NG-HM had the highest PN emission. Figures 

102 and 103 show that over 70 percent of the PN emitted from the HD-D-HM was solid. This is 

similar to the HD-D-NE vehicle but drastically different from the LD-HE and the HD-NG-HM

vehicle, where over 70 percent of PN was volatile. Furthermore, this is slightly different from the 

MD-HE vehicle, where more volatile fraction of the PN was observed. However, in general, the 

volatile PN fraction for the HD and MD diesel vehicles were comparable, suggesting little 

influence of lube oil aging and oil/consumption on PN emissions. 

 Figures 104 and 105 show a typical size distribution for the HD-D-NE using the fresh 

and aged oil. The data are shown for the cold-start and hot-start portions of the test cycles using 

TxLED fuel at 72°F. The total and solid distributions exhibit a similar monomodal lognormal 

size distribution structure that consists of an accumulation mode. The accumulation mode peaks 

between 50 nm and 70 nm, similar to what was observed with the MD-NE. For the HD-D-HM, 

as shown in Figures 106 and 107, the total and solid particle size distributions were very similar 

to that for the HD-D-NE. No notable differences in the size distributions were observed between 

the fresh oil and aged oil, the cold-start and hot-start, or the NE and HM. 

FIGURE 100. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (DIESEL, 

HIGH MILEAGE VEHICLE, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)
221 

FIGURE 101. SOLID AND VOLATILE PARTICLE NUMBER CONCENTRATION (DIESEL, 

HIGH MILEAGE VEHICLE, AGED OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 102. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL 

PARTICLES (HD DIESEL, HIGH MILEAGE VEHICLE, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)
222 

FIGURE 103. SOLID AND VOLATILE PARTICLES AS A PERCENT OF TOTAL 

PARTICLES (HD DIESEL, HIGH MILEAGE VEHICLE, AGED OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 104. NUMBER-WEIGHTED SIZE DISTRIBUTION (HD DIESEL, NORMAL 

EMITTER, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)
223 

FIGURE 105. NUMBER-WEIGHTED SIZE DISTRIBUTION (HD DIESEL, NORMAL 

EMITTER, AGED OIL)

(No Statistical Analyses Were Performed On These Data)

FIGURE 106. NUMBER-WEIGHTED SIZE DISTRIBUTION (HD DIESEL, HIGH MILEAGE 

VEHICLE, FRESH OIL)

(No Statistical Analyses Were Performed On These Data)
224 

FIGURE 107. NUMBER-WEIGHTED SIZE DISTRIBUTION (HD DIESEL, HIGH MILEAGE 

VEHICLE, AGED OIL)

(No Statistical Analyses Were Performed On These Data)

10.6 PM Apportionment

10.6.1 Regulated Emissions and Fuel Economy 

Regulated emissions and fuel economy data for each set of duplicate tests conducted on 

each of the two test vehicles were averaged and are presented in Table 104. The emissions and 

fuel usage were found to be similar for the two test vehicles with the HM having somewhat 

lower carbon monoxide and PM emissions than the NE. The aged oil gave higher hydrocarbon 

and oxides of nitrogen emissions and lower PM emissions than the fresh oil; however, there was 

some overlap of data in all these cases.

TABLE 104. REGULATED EMISSIONS AND FUEL ECONOMY FOR THE HEAVY-DUTY 

DIESEL-FUELED VEHICLES

(No Statistical Analyses Were Performed On These Data)

NE HM

Fresh Oil Aged Oil Fresh Oil Aged Oil

HC, g/mi 0.61 0.65 0.66 0.71

CO, g/mi 6.50 6.20 5.41 5.49

NOX, g/mi 17.65 19.97 18.20 19.07

PM, mg/mi 860 783 665 637

Fuel Usage, lb/mi 1.58 1.59 1.65 1.68
225 

10.6.2 Estimates for Vehicle Oil Consumption Rates

As was the case for the natural gas-fueled vehicles, the XRF analyses of the HD diesel 

samples gave significantly higher levels of the elements in the exhaust PM than did the ICP-MS 

analyses. Also, although analyses of the fresh and aged oils showed similar levels of calcium, 

sulfur, phosphorous, and zinc, analyses of the PM by XRF gave significantly different levels of 

these elements for the fresh and aged oil tests. The levels of these elements in the PM for the 

fresh oil tests were approximately twice as high as the levels detected in the PM for the aged oil 

tests for both vehicles. All of these variations in the elements data made it difficult to calculate 

oil consumption rates with any confidence. Table 105 presents the variation in the results when 

the calcium emissions are used to calculate oil consumption rates for the two test vehicles. As 

can be seen in Table 105, XRF results give nearly equivalent oil consumption rates for the two 

test vehicles with fresh oil and lower, but similar, rates for the aged oil. The ICP-MS results also 

give oil consumption rates that are similar for the two vehicles with aged oil, but the fresh oils 

show a large difference for the two vehicles. These two vehicles were in-use buses and service 

data was available for both. The NE was reported as requiring one quart of oil per 971 miles 

(858 mg/mi) and the HM as having high blowby and requiring one quart of oil per 145 miles 

(5745 mg/mi). The records for the NE indicate that its calculated oil consumption rates may be 

high by a factor of nearly two except for the aged oil case by ICP-MS. Because of its high 

blowby rate, the service data for oil addition for HM does not provide any additional insight for 

comparison to the estimated exhaust emission rate of oil. In this case, blowby is not vented to 

the exhaust and any losses of oil related to blowby would not be included in exhaust-based 

calculations for estimating oil consumption. 

TABLE 105. VARIATIONS IN ESTIMATED OIL CONSUMPTION RATES FOR THE 

HEAVY-DUTY DIESEL-FUELED VEHICLES

(No Statistical Analyses Were Performed On These Data)

NE HM

Fresh Oil Aged Oil Fresh Oil Aged Oil

Calcium Emissions by

XRF, μg/mi 5064 2870 5045 2397 

Calcium Emissions by

ICP-MS, μg/mi 4361 1369 1603 1137 

Calcium Oil Concentrations, 

XRF, μg/g 2623 2707 2623 2707 

Calcium Oil Concentrations, 

ICP-MS, μg/g 2275 2270 2275 2270 

Oil Consumption Rate by 

XRF, mg/mi 1931 1060 1923 885 

Oil Consumption Rate by 

ICP-MS, mg/mi 1917 603 705 501 

*An oil consumption rate of 833 mg/mi equals one quart per 1000 miles
226 

10.6.3 Wear Elements

While analyses of the oils (both as supplied and from the crankcase before testing) 

showed much higher levels of selected wear elements in the aged oil (Al, Cr, Mn, Fe, Ni, Cu, 

Mo, Pb) than in the fresh oil, analyses of the PM, with the exception of lead, did not reflect these 

differences. In fact the fresh oil tests on average produced nearly twice the amount of total wear 

metals in the PM as did the aged oil (3400 μg/mi vs. 1900 μg/mi). The high mileage did show 

higher PM sulfur levels, possibly due to a more active conversion of sulfur to sulfate in the 

vehicle’s catalyst.

10.6.4 Carbon Analyses for Elemental and Organic Content of PM 

Elemental, organic, and total carbon content results from TOR analyses of the PM filters 

from the diesel-fueled heavy-duty vehicle tests are presented in Table 106. The total measured 

PM values for each vehicle are also shown for comparison. Because of the disparity of the 

calculated oil consumption rates with the fresh and aged oils, separate results for each oil are 

presented in the table. The total carbon emission rate by TOR was found to be higher than the 

total PM emission rate. The OC fraction of the TC was found to be higher for the HM compared 

to the NE (18 percent vs. 14 percent) as well as higher for the aged oil tests compared to the 

fresh oil tests (17 percent vs. 15 percent). Overall, the data for the two vehicles were relatively 

similar. Table 107 combines the total carbon results with results for the oil and wear elements 

for a second comparison with the total measured PM results. The overall differences in the PM 

elements (oil and wear) between fresh and aged oils are illustrated in the table.

TABLE 106. TOTAL, ELEMENTAL, AND ORGANIC CARBON EMISSIONS

(No Statistical Analyses Were Performed On These Data)

EMISSIONS, mg/mi

NE HM

Fresh Oil Aged Oil Fresh Oil Aged Oil

EC 828 712 569 584

OC 123 132 122 131

TC 952 844 691 715

PM 860 783 665 637
227 

TABLE 107. CARBON AND OTHER ELEMENT TOTALS COMPARED TO TOTAL PM

(No Statistical Analyses Were Performed On These Data)

EMISSIONS, mg/mi

NE HM

Fresh Oil Aged Oil Fresh Oil Aged Oil

Total Carbon 952 844 691 715

Elements * 24 12 25 11

Hydrogen Mass for OC ** 15 17 15 17

Total 991 873 731 743

Measured PM 854 783 665 637

* Element mass from XRF analyses. Mass for sulfur and phosphorous assumed to be 

sulfate and phosphate 

** Mass for 1.5 hydrogens per carbon assumed

10.6.5 Estimation of Unburned Oil Content

The oils utilized for the heavy-duty diesel-fueled vehicles were also spiked with the 

hexatriacontane-d74 tracer; however, in this case, the measured concentrations of the tracer in 

fresh oil and aged oil were different when analyzed by GC-MS, 207 μg/g oil for the fresh oil and 

127 μg/g oil for the aged oil. The total hopanes and steranes were also found to be present at 

different levels in the two oils; 179 μg/g oil for the fresh oil and 337 μg/g for the aged oil. 

Because of the variation in the oils, calculations for the unburned oil content of the PM were 

carried out for both oils and for both vehicles using the appropriate PM and oil concentrations. 

Table 108 presents oil concentrations and PM emission rates for hexatriacontane-d74, total 

hopanes and steranes, the unresolved complex mixture (UCM) from the GC-MS alkane analyses, 

and the corresponding calculated unburned oil emission rates for each set of PM and oil data. 

TABLE 108. ESTIMATION OF UNBURNED OIL USING VARIOUS TRACERS

(No Statistical Analyses Were Performed On These Data)

NE HM

Fresh Oil Aged Oil Fresh Oil Aged Oil

Hexatriacontane-d74 in PM, μg/mi 24.7 36.0 16.8 9.4

Hexatriacontane-d74 in oil, μg/g 207 127 207 127

Unburned oil in PM, mg/mi 119 283 81 74

Total Hopanes & Steranes in PM, μg/mi 20.5* 23.8 14.6* 20.6*

Total Hopanes & Steranes in Oil, μg/g 179 337 179 337

Unburned oil in PM, mg/mi 115 71 82 61

Total UCM in PM, mg/mi 31.8 21.2 27.5 30.0

Total UCM in oil, g/g 0.247 0.247 0.247 0.247

Unburned oil in PM, mg/mi 129 86 111 121

*Significant levels of hopanes and steranes also observed in gas phase (30 to 45 percent). Not

 noted for MD vehicle samples
228 

All three methods of determining unburned oil gave similar emission rates for the NE 

using fresh oil (115 to 129 mg/mi), but varied widely for the NE using aged oil (71 to 283 

mg/mi). A substantial amount of hopanes and steranes (30 to 45 percent of the total) was also 

found in the gas phase for three of the four sample sets. This level of hopanes and steranes was 

not observed in the medium-duty vehicle tests and was not expected. Also of note was the 

observation that the PM did contain fuel range C12 to C19 alkanes (0.6 to 0.8 mg/mi) on the same 

order as oil range C20 to C40 alkanes (0.9 to 1.8 mg/mi). The C12 to C19 fraction was slightly 

higher for the HM PM (38 percent) compared to the NE PM fraction (30 percent). PM alkanes 

were on average 20 percent of the total (PM plus gas phase) alkanes.

Table 109 presents a comparison of the calculated unburned oil estimates to the organic 

carbon (OC) component of the PM. All three methods give unburned oil emission rates that are 

in good agreement with the OC for the NE fresh oil tests, but only the UCM estimates appear to

track the OC for the HM test. None of the three methods produced calculated rates that were 

similar to the NE aged oil results. All three methods also gave calculated unburned oil emissions 

rates for the HM that were lower than the measured OC rate and indicate the possibility of fuel 

derived components or partially burned oil components at higher levels in the HM than in the 

NE. The higher fraction of the C12 to C19 alkanes to the total alkanes in the HM PM (38 percent) 

compared to the NE (30 percent) could support this supposition. If the unburned oil estimates 

are averaged for the three methods with the associated mass of the hydrogen removed, the results 

indicate that 89 percent of the NE OC is unburned oil while only 60 percent of the HM OC is 

unburned oil. 

TABLE 109. COMPARISON OF UNBURNED OIL ESTIMATES TO OC

(No Statistical Analyses Were Performed On These Data)

NE HM

Fresh Oil Aged Oil Fresh Oil Aged Oil

Hexatriacontane-d74, mg/mi 119 283 81 74

Hopanes & Steranes, mg/mi 115 71 82 61

UCM, mg/mi 129 86 111 121

OC, mg/mi 123 132 122 131

10.6.6 PAH PM Emissions

A total of 55 different PAH were detected in the PM from the heavy-duty diesel-fueled 

vehicles tested in this study. Total PAH emission rates ranged from 0.36 mg/mi for the NE aged 

oil tests to 0.74 mg/mi for the HM aged oil tests. While the aged oil contained approximately 

four times the concentration of these 55 PAH compounds as did the fresh oil (147μg/g oil 

compared to 35 μg/g oil), the fresh and aged oil tests on average over the two vehicles gave 

nearly equivalent emissions results (0.55 mg/mi). These equivalent results indicate that the PAH 

compounds in PM primarily originate from the fuel and not the oil. On average the HM had 

higher PM PAH emission rates than the NE (0.69 mg/mi for the HM and 0.40 mg/mi for the 

NE). When only the higher molecular weight PAH compounds were considered 

(benz(a)anthracene and heavier), the difference was even greater (29 μg/mi for the HM and 6 
229 

μg/mi for the NE). These PAH results also support the suggestion of a larger fraction of fuel 

derived material in the HM PM compared to the NE PM.

10.6.7 Summary

 A number of observations regarding the make-up of the heavy-duty vehicle PM follow: 

• Calculations for oil consumption rates for the heavy-duty diesel fueled vehicles 

varied considerably due to variations in measured levels of oil derived elements in the 

PM. Variations occurred between the two analysis techniques (XRF or ICP-MS) and 

between samples from the two oils tested with each of the two vehicles. Calculated 

oil consumption rates were more consistent for a single oil tested in both test vehicles 

than for both oils tested in a single vehicle. 

• Despite higher concentrations of wear elements in the aged oil, the PM from the fresh 

oil tests had higher emission rates of the wear elements than did the aged oil.

• TOR analyses showed a higher fraction of the HM PM to be OC (18 percent) 

compared to the NE PM (14 percent). These percentages were generally lower than 

those obtained for the medium-duty vehicles (22 and 29 percent). 

• Total PM carbon was observed to be higher than the measured PM emission rate for 

both vehicles. 

• Three methods were utilized to calculate unburned oil in the PM. All three methods 

gave unburned oil rates similar to the OC rates for the NE tests with fresh oil, but 

none gave similar results for the NE with aged oil. All three methods gave oil 

consumption rates lower than the OC rates for both fresh and aged oil tests with the 

HM, indicating the possibility of fuel derived compounds in the PM at more 

significant levels than previous medium-duty or natural gas-fueled heavy-duty tests. 

• The unburned oil is estimated to be 89 percent of the OC for the NE, but only 

62 percent of the HM. 

• The HM had higher PM PAH emission rates than the NE (0.69 mg/mi vs 0.40 mg/mi) 

also indicating more fuel derived combustion products in the HM PM. Also, alkanes 

in the fuel range size (C12 to C19) made up a larger fraction of the total PM alkanes in 

the case of the HM (38 percent) compared to the NE (30 percent). 

10.7 Heavy-Duty Diesel Vehicles Major Technical Findings

Fresh and Aged oil

Both vehicles produced nominally lower PM emissions with aged oil compared to fresh oil. 

Fuel

Only TxLED diesel fuel was used.
230 

Normal and High Particulate Matter (High Mileage) Emitter

The normal PM emitter produced higher PM than the high mileage vehicle; approximately 

0.82g/mi for the NE compared to about 0.65g/mi for the high mileage bus. 

Normal (72°F) and Low (20°F) Temperature

No low temperature tests were performed with the HD diesel vehicles.

Particle Number and Size Distributions

Particle Number 

• For the HD D NE, the exhaust PN concentration ranged from about 12x106 part./cm3 to 

18x106 part./cm3. This is comparable to the MD NE and the HD NG NE. The PN 

composition and size distribution are different from those emitted from the HD NG NE and 

similar to those emitted from the MD NE.

• No notable differences were observed between cold-start and hot-start and between fresh and 

aged oils. 

• Seventy to ninety percent of the number of particles emitted from the HD D NE were solid in 

nature. This is much different from the HD NG NE that was dominated by volatile particles. 

It is also slightly different from the MD NE that had more volatile PN than that observed 

with the HD D NE. While total PN emission is similar between HD D NE and HD NG NE, 

the solid or soot PN emission from the HD D NE is much higher than that observed with HD 

NG NE. This suggests that fuel is the major contributor of PN in HD D, while lube oil is the 

major contributor of PN in HD NG. Even if the oil consumption is similar between the two 

vehicle types, the absence of soot or solid particle surface area in the HD NG vehicles 

promotes sulfuric acid and hydrocarbon particle nucleation and growth. The soot present in 

diesel exhaust dominates PN emission, and changes in lube oil volatility or properties have a 

lesser influence on PN. 

• For the HD D high mileage (HM) vehicle, the exhaust PN concentration ranged from 10x106

part./cm3 to 16x106 part./cm3. This concentration range is similar to that of the HD D NE and 

the MD NE and MD HE, but much lower than that of the LD HE and the HD NG HM. This 

further demonstrates that when soot dominates PN emission, lube oil contribution to PN is 

minimized.

• It is interesting to note that among the vehicles tested, the LD HE and HD NG HM vehicles 

had the highest PN emission. 

• Over 70 percent of the PN emitted from the HD D HM was solid. This is similar to the HD D 

NE vehicle but drastically different from the LD HE and the HD NG HM vehicle, where over 

70 percent of PN was volatile. Furthermore, this is slightly different from the MD HE 

vehicle, where more volatile fraction of the PN was observed. 

• In general, the volatile PN fraction for the HD and MD diesel vehicles were comparable, 

suggesting little influence of lube oil aging and oil consumption on PN emissions. 
231

• For both fresh and aged oils in the HD D NE, the total and solid distributions exhibit a 

similar monomodal lognormal size distribution structure that consists of an accumulation 

mode. The accumulation mode peaks between 50 nm and 70 nm, similar to what was 

observed with the MD NE. 

• For the HD D HM, the total and solid particle size distributions were very similar to that for 

the HD D NE.

• No notable differences in the size distributions were observed between the fresh oil and aged 

oil, the cold-start and hot-start, or the NE and HM. 

HD Diesel PM Apportionment

• Calculations for oil consumption rates for the heavy-duty diesel fueled vehicles varied 

considerably due to variations in measured levels of oil derived elements in the PM. 

Variations occurred between the two analysis techniques (XRF or ICP-MS) and between 

samples from the two oils tested with each of the two vehicles. Calculated oil consumption 

rates were more consistent for a single oil tested in both vehicles than for both oils tested in a 

single vehicle.

• Despite higher concentrations of wear elements in the aged oil, the PM from the fresh oil 

tests had higher emission rates of the wear elements than from tests with the aged oil. 

• TOR analyses showed a higher fraction of the HM PM to be OC (18 percent) compared to 

the NE PM (14 percent). These percentages were generally lower than those obtained for the 

medium-duty diesel vehicles (22 and 29 percent). 

• Total PM carbon determined by TOR analysis was observed to be higher than the measured 

PM emission rate for both vehicles.

• Three methods were utilized to calculate unburned oil in the PM. All three methods gave 

unburned oil rates similar to the OC rates for the NE tests with fresh oil, but none gave 

similar results for the NE with aged oil. All three methods gave oil consumption rates lower 

than the OC rates for both fresh and aged oil tests with the HM, indicating the possibility of 

fuel derived compounds in the PM at more significant levels than in previous medium-duty 

or natural gas-fueled heavy-duty vehicle tests.

• The unburned oil is estimated to be 89 percent of the OC for the NE, but only 62 percent for 

the HM. 

• The HM had higher PM PAH emission rates than the NE (0.69 mg/mi vs 0.40 mg/mi), also 

indicating more fuel derived combustion products in the HM PM. Also, alkanes in the fuel 

range size (C12 to C19) made up a larger fraction of the total PM alkanes in the case of the 

HM (38 percent) compared to the NE (30 percent). 

Particle Size Distribution
232 

11.0 FUTURE WORK

Follow-up studies should assess the methods of PM allocations used in this study on 

vehicles representing the diverse spectrum between normal emitters and high emitters, and

estimate the precision of the allocations obtained by running multiple analyses. Vehicles should 

be tested with fuels without a UCM of alkanes, or without hopanes and steranes, in order to help 

clarify the potential confounding (or lack thereof) when markers are parented by both fuel and 

lubricant. Studies should be conducted to understand the relative frequency of various types and 

intensities of ‘high emitters’ to facilitate modeling of the on-road vehicle fleet.

Future work could consider testing emissions from diesel vehicles equipped with 

normally-functioning particle filters to determine if this type of aftertreatment system produces 

similar results. Also, it would be informative to utilize the latest engine and emissions system 

hardware for all the vehicles to determine if the considerable efforts by regulators and OEMs 

have impacted PM levels. Noting that aged lubricants sometimes produces less PM than fresh 

oil, it would be interesting to investigate the effects of base oil volatility and type (i.e., mineralbased verses synthetic) on PM and SVOC formation. 
233 

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Emission Inventory Data for the South Coast Air Basin. 

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Source Apportionment of Secondary Organic Aerosol During a Severe Photochemical 

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Transportation and Air Quality U.S. Environmental Protection Agency Ann Arbor, MI, 

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C.; Crews, W.C.; Snow, R.; Gabele, P.; Santos, R.; Tierney, G.; Cantrell B., Methods of 

Characterizing the Distribution of Exhaust Emissions from Light-Duty, GasolinePowered Motor Vehicles in the U.S. Fleet; J. Air Waste Manage. Assoc, 2010, 60, 1376-

1378. 

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1618-1626. 

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Chow, J.C.; Gabele, N.P.A.; Crews, W.; Snow, R.; Clark, N.; Wayne S.; Lawson D.R., 

Variations in Speciated Emissions from Spark-Ignition and Compression Ignition Motor 

Vehicles in the California's South Coast Air Basin; J. Air Waste Manage. Assoc., 2007,

57, 705-720. 

7. Risk Reduction Plan to Reduce Particulate Matter Emissions from Diesel-Fueled Engines 

and Vehicles, California Air Resources Board, October 2000. 

8. Seagrave J.; McDonald, J.D.; Gigliotti, A.P.; Nikula, K.L.; Seilkop, S.K.; Gurevich M., 

Mutagenicity and In Vivo Toxicity of Combined Particulate and Semi-Volatile Organic 

Fractions of Gasoline and Diesel Engine Emissions; Toxicol. Sci., 2002, 70, 212-226. 

9. McDonald, J.D., Eide, I.; Seagrave, J.C.; Zielinska, B.; Whitney, K.; Lawson, D.R.; 

Mauderly J.L., Relationship Between Composition and Toxicity of Motor Vehicle 

Emission Samples; Environ. Health Persp., 2004, 112, 1527-1538. 

10. Whitney, K. (2000) Collection of In-Use Mobile Source Emissions Samples for Toxicity 

Testing. Final Report prepared for National Renewable Energy Laboratory, Golden, CO, 

NREL Subcontract ACI-9-18148-02, October 2000. 

11. Kleeman, M.J.; Cass, G.R. A 3D Eulerian Source-Oriented Model for an Externally 

Mixed Aerosol; Environ. Sci. Technol. 2001, 35, 4834-4848. 
234 

12. California Air Resources Board, http://www.arb.ca.gov/ei/emissiondata.htm. 2008 

Emission Inventory Data for the South Coast Air Basin. 

13. Kleeman, M.J.; Ying, Q.; Lu, J.’ Mysliwiec M.J.; Griffin, R.J.; Chen, J.; Clegg, S. Source 

Apportionment of Secondary Organic Aerosol During a Severe Photochemical Smog 

Episode; Atmos. Environ. 2007, 41, 576-591. 

14. Ying, Q.; Fraser, M.P.; Griffin, R.J., Chen, J., Kleeman, M.J. Verification of a SourceOriented Externally Mixed Air Quality Model During a Severe Photochemical Smog 

Episode; Atmos. Environ. 2007, 41, 1521-1538. 

15. Zielinska, B., J. Sagebiel, J.D. MacDonald, K. Whitney, D.R. Lawson (2004). Emission 

Rates and Comparative Chemical Composition from Selected In-Use Diesel and Gasoline 

Fueled Vehicles. J. Air Waste Manage. Assoc. 54, 1138-1150. 

16. Chuang, J.C., M.R. Kuhlman, and N. Wilson (1990). Evaluation of Methods for 

Simultaneous Collection and Determination of Nicotine and Polynuclear Aromatic 

Hydrocarbons in Indoor Air. Environ. Sci. Technol., 24, 661-665. 

17. Atkinson, R., J. Arey, A.M. Winer and B. Zielinska (1988). "A Survey of Ambient 

Concentrations of Selected Polycyclic Aromatic Hydrocarbons (PAH) at Various 

Locations in California." Final Report, prepared under Contract No. A5-185-32, for the 

California Air Resources Board, Sacramento, CA, by Statewide Air Pollution Research 

Center, University of California, Riverside, CA. 

18. Chow, J.C.; Watson, J.G.; Crow, D.; Lowenthal, D.H.; Merrifield, T., (2001), 

Comparison of IMPROVE and NIOSH Carbon Measurements. Aerosol Sci.Technol., 34, 

23-34. 

19. Peterson, M.R.; Richards, M.H. Thermal-optical-transmittance Analysis for Organic, 

Elemental, Carbonate, Total Carbon, and OCX2 in PM2.5 by the EPA/NIOSH Method, 

in Proceedings, Symposium on Air Quality Measurement Methods and Technology2002, Winegar, E.D., Tropp, R.J., Eds.; Air & Waste Management Association: 

Pittsburgh, PA, 2002, pp. 83-1-83-19.

20. California Air Resources Board’s Emissions Inventory Series, Volume 1. Issue 9, The 

Federal Test Procedure and Unified Cycle. 

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November 1998. 

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Contributions to Particulate Matter Emission from Light-Duty Gasoline and Heavy-Duty 

Diesel Vehicles; Environ. Sci. Technol., 2008, 42, 235-242. 
APPENDIX A
 

HEXATRIACONTANE TRACER BLENDING PROTOCOL 
 

Protocol For Deuterated N-Alkane Handling, Storage, and Mixing 

5/14/07 Rev0 MED/DH 

Readme: 

I followed the SOP below and I have the following notes to make. I found that heating the oil on 

the hotplate did a very good job of dissolving the n-alkane. I would consider it an 

essential, not optional step. A stir bar was used but I found that a large stir bar (18” long) 

worked even better since the oil is so viscous, especially when cool. Use both stir 

methods if you have them. Also, I was able to transfer the relatively hot beaker of oil to a 

large container by myself, but I think it’s a job best suited for two people (one to hold the 

funnel, one to pour). 

- Dave Hardie 

Objective: 

Completely dissolve 100 g of deuterated n-alkane tracer in 20 quarts of motor oil, contained in a 

6 gallon fuel/oil container with no contamination of the container, laboratory facilities, 

clothing, or skin with the tracer. 

Equipment: 

•	 6 gallon or larger plastic fuel/oil container with sealing pour spout 

•	 Two 5-liter Pyrex beakers 

•	 Large glass or plastic funnel with a large bore neck for transferring oil from beaker to 6 

gallon container 

•	 20 quarts of lube oil (Mobil/Exxon 15W40 for diesel engines, classification CH4 or 

better, meeting EGR engine requirements) 

•	 Magnetic stirrer/hotplate 

•	 Large magnetic stirring bar (~2-3”) 

•	 Magnetic stir bar retrieval rod (long enough to retrieve stirrer from 5L beaker) 

•	 Tyvek coveralls 

•	 Latex gloves 

•	 Plastic garbage bags for (1) discarded Kimwipes, Tyvek coveralls, tracer vials, and 

gloves, and (2) 20 empty quart containers of oil. 

•	 2 vials (50 g each) of deuterated hexatriacontane powder delivered from DRI 

Overview: 

The deuterated tracer (n-hexatriacontane, 100g) is to be dissolved in a total of 20 quarts of oil. 

This tracer was delivered in two separate vials, each containing 50 g of compound as a 

white powder. The dissolving of this material will be done in 4 batches of 4 quarts each, 

with the remaining oil used to rinse down the equipment used to dissolve and transfer 

each batch to the 6 gallon container. A second beaker is used to hold the stir bar and 

A-1
 

 

retrieval rod between batches. Latex gloves and Tyvek coveralls will be worn while 

conducting these steps. Bottles in which the oil was delivered, as well as the tracer vials, 

coveralls, and gloves will be discarded in a sealed plastic bag to prevent subsequent 

accidental contamination of lab facilities, hands, and clothing. 

Other than ordinary laboratory procedures to prevent spillage, the only special care required is 

avoiding any traces of the deuterated alkane or alkane-containing oil on the outside of the 

6 gallon container, clothing, hands, or lab equipment. Glassware should be clean and 

dry, but no special cleaning procedures are needed. 

Note: This protocol assumes that the new motor oil being used is obtained in 1-quart plastic 

bottles. If delivered in larger packages (e.g. 1-gallon), then one additional 1-liter or 1.5­

liter beaker can be used to measure and transfer the desired amounts of oil from the large 

container to the 5-liter beakers. It is not necessary that the tracer be uniformly dissolved 

through the entire 20 quarts in the 6 gallon container, as it will be thoroughly mixed when 

added to the engine. 

Procedure: 

1.	 N- hexatriacontane-d74 is packed in two separate vials; each contains 50 g of this compound. 

They should be kept in a safe and clean place, no need to refrigerate. 

2.	 Before handling the tracer, assemble all needed equipment. Label the 6 gallon container 

using an indelible marker and/or tied-on tag “15W40 diesel lube oil with alkane tracer,” and 

put on Tyvek coveralls and gloves. 

3.	 Open the 6 gallon container and insert the funnel, being sure that it is sufficiently vertical to 

allow oil to be poured into the container without the funnel overflowing. 

4.	 Place the 5 L beaker on the hotplate and place the stir bar in it. 

Batch 1 

5.	 Add 2 quarts of oil to the beaker. 

6.	 Carefully add approximately half of one vial of tracer to the beaker, being careful not to 

allow the light powder to become airborne. 

7.	 Add another 2 quarts of oil to the beaker, and turn on the stirrer to dissolve the tracer. The 

tracer should dissolve fairly readily. The oil may be heated slightly to accelerate this 

process. 

8.	 When dissolved, turn off the stirrer (and hotplate if used) and use the rod to retrieve the 

stirrer. Transfer the stirrer and rod to the other 5 L beaker, avoiding dripping oil on any 

surfaces. 

9.	 Check gloves to be sure they do not have oil on the palms or fingertips making them slippery. 

If so, remove and discard them in the plastic bag, turning them inside out, and put on fresh 

gloves. Pour the oil from the beaker into the 6 gallon container, carefully avoiding 

overflowing the funnel and any drips. After pouring, if necessary, Kimwipes can be used to 

remove small amounts of oil on the beaker pour spout to prevent drips. These should be 

immediately discarded in the plastic bag, and not placed on laboratory surfaces. 

A-2
 

 

Batch 2 

10. Repeat steps 5 through 9 using the second half of the tracer in the first vial and another 4 

quarts of oil (quarts 5 to 8). 

Batch 3 

11. Repeat steps 5 through 9 using the first half of the second vial of tracer and another 4 quarts 

of oil (quarts 9 to 12). 

Batch 4 

12. Repeat steps 5 through 9 using the remainder of the tracer and another 4 quarts of oil (quarts 

13 to 16). 

Rinsing Equipment to Capture Remaining Tracer 

13. Set aside the hotplate/stirrer. 

14. Add 1⁄2 quart of oil to the beaker used for mixing, pouring oil down the sides of the beaker to 

rinse down the tracer-containing oil (quart 17). 

15. Pour the rinse oil from the beaker into the 6 gallon container. 

16. Repeat steps 14 and 15 three times, using 1⁄2 quart of oil each time (quarts 17 and 18). 

17. Use 1 quart of oil to rinse the tracer containing oil off of the stir bar and retrieval rod by 

holding the retrieval rod with stir bar attached over the second beaker so the stir bar is 

approximately 3 inches above the bottom of the beaker. Slowly pour the oil down the side of 

the rod so that it coats and rinses the rod and stir bar. Do not let the stir bar come in contact 

with the rinse oil in the bottom of the beaker. (quart 19) 

18. Transfer the stir bar and retrieval rod to the beaker used for mixing tracer. 

19. Pour the rinse oil from the rod and stirrer into the 6 gallon container. 

20. Rinse the beaker with 1⁄2 quart of oil, pouring down the sides to wash down tracer containing 

oil, and pour into the 6 gallon container (quart 20). 

21. Repeat step 20 with the last 1⁄2 quart of oil (quart 20). 

22. Remove the funnel from the container and place in one of the beakers. 

23. If any tracer-containing oil is on the gloves, remove the gloves (turning inside out, and 

discarding in the garbage bag), and put on fresh gloves. 

24. Replace the filler cap on the 6 gallon container. 

25. Discard tracer vials in the plastic garbage bag. 

26. Discard the empty oil bottles in the other plastic garbage bag(s) and seal with a twist tie. 

27. Clean the funnel, stir bar, retrieval rod and beakers using your standard laboratory procedures 

for organics. 

28. Remove the gloves, turning them inside-out, and discard in the plastic bag. 

29. Remove the Tyvek coveralls, turning them inside-out, discard in the plastic bag, and seal the 

plastic bag. 

30. If not immediately being taken to the field, store the 6 gallon container in a secure area. 

Contact: 

Dave Hardie - Chemist 

Research Scientist 

University of Washington, DEOHS 

A-3
4225 Roosevelt Way, NE – Suite 100 

Campus Box: 354695
 

Seattle, WA 98105 

206 616-2679 

dhardie@u.washington.edu 

Mark Davey – Project Manager 

University of Washington, DEOHS
 

206 221-7721 

medavey@u.washington.edu 

End 

A-4
APPENDIX B
 

TWO COLD CO FUELS ANALYSES RESULTS
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TABLE B1. HYDROCARBON SPECIATION RESULTS OF TWO COLD CO FUELS
 

Original 

COLD CO 

Fuel 

New 

Cold CO 

Fuel 

EM-5574-F 

EM6802-F Original ­

New 

Original / 

New 

Group Component %Vol %Vol Difference, % Ratio 

Paraffin Propane 0.014 0.004 0.01 3.5 

Paraffin n-Butane 0.528 2.422 -1.89 0.2 

Paraffin n-Pentane 5.841 5.173 0.67 1.1 

Paraffin n-Hexane 2.338 2.113 0.23 1.1 

Paraffin n-Heptane 0.918 0.875 0.04 1.0 

Paraffin n-Octane 0.287 0.314 -0.03 0.9 

Paraffin n-Nonane 0.834 0.787 0.05 1.1 

Paraffin n-Decane 1.218 1.093 0.13 1.1 

Paraffin n-Undecane 0.269 0.093 0.18 2.9 

Paraffin n-Dodecane 0.006 0.008 0.00 0.8 

Paraffin n-Tridecane 0 0.003 0.00 0.0 

I-Paraffins i-Butane 2.959 4.022 -1.06 0.7 

I-Paraffins 2,2-Dimethylpropane 0.13 0.081 0.05 1.6 

I-Paraffins i-Pentane 20.161 17.194 2.97 1.2 

I-Paraffins 2,2-Dimethylbutane 0.486 0.401 0.09 1.2 

I-Paraffins 2,3-Dimethylbutane 0.58 0.475 0.11 1.2 

I-Paraffins 2-Methylpentane 2.379 1.994 0.39 1.2 

I-Paraffins 3-Methylpentane 1.317 1.119 0.20 1.2 

I-Paraffins 2,4-Dimethylpentane 0.178 0.137 0.04 1.3 

I-Paraffins 2,2,3-Trimethylbutane 0.041 0.037 0.00 1.1 

I-Paraffins 3,3-Dimethylpentane 0.062 0.055 0.01 1.1 

I-Paraffins 2-Methylhexane 1.096 1.01 0.09 1.1 

I-Paraffins 3-Methylhexane 0.575 0.516 0.06 1.1 

I-Paraffins 2,2,4-Trimethylpentane 3.741 4.542 -0.80 0.8 

I-Paraffins 2,2-Dimethylhexane 0.028 0.035 -0.01 0.8 

I-Paraffins 2,2,3-Trimethylpentane 0.072 0.069 0.00 1.0 

I-Paraffins 2,5-Dimethylhexane 0.228 0.246 -0.02 0.9 

I-Paraffins 2,4-Dimethylhexane 0.188 0.189 0.00 1.0 

I-Paraffins 3,3-Dimethylhexane 0.019 0.018 0.00 1.1 

I-Paraffins 2,3,4-Trimethylpentane 0.249 0.207 0.04 1.2 

I-Paraffins 2,3-Dimethylhexane 0.064 0.055 0.01 1.2 

I-Paraffins 2-Methylheptane 0.177 0.187 -0.01 0.9 

I-Paraffins 4-Methylheptane 0.069 0.068 0.00 1.0 

I-Paraffins 3-Methylheptane 0.145 0.151 -0.01 1.0 

I-Paraffins 3-Ethylhexane 0.103 0.113 -0.01 0.9 

I-Paraffins 2,2,5-Trimethylhexane 0.023 0.016 0.01 1.4 

I-Paraffins 2,4-Dimethylheptane 0.023 0.015 0.01 1.5 

I-Paraffins 2,6-Dimethylheptane 0.036 0.028 0.01 1.3 

I-Paraffins 2,5-Dimethylheptane 0.062 0.042 0.02 1.5 

I-Paraffins 3,5-Dimethylheptane 0.018 0.011 0.01 1.6 

I-Paraffins 2,3-Dimethylheptane 0.042 0.022 0.02 1.9 

I-Paraffins 3,5-Dimethylheptane 0.023 0 0.02 NA 

B-1
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Original 

COLD CO 

Fuel 

New 

Cold CO 

Fuel 

EM-5574-F 

EM6802-F Original ­

New 

Original / 

New 

Group Component %Vol %Vol Difference, % Ratio 

I-Paraffins 4-Ethylheptane 0.014 0.008 0.01 1.8 

I-Paraffins 4-Methyloctane 0.101 0.052 0.05 1.9 

I-Paraffins 2-Methyloctane 0.146 0.076 0.07 1.9 

I-Paraffins Heptane, 3-ethyl­ 0.026 0 0.03 NA 

I-Paraffins 3-Methyloctane 0.172 0.116 0.06 1.5 

I-Paraffins C10 - IsoParaffin - 1 0.013 0.006 0.01 2.2 

I-Paraffins 2,2,4-trimethylheptane 0.073 0.092 -0.02 0.8 

I-Paraffins C10-isoparaffin-x 0 0 0.00 NA 

I-Paraffins 2,3-Dimethyloctane 0.058 0.087 -0.03 0.7 

I-Paraffins 2,2-Dimethyloctane 0.097 0.094 0.00 1.0 

I-Paraffins 2,5-Dimethyloctane 0.142 0.15 -0.01 0.9 

I-Paraffins 2,7-Dimethyloctane 0.057 0.053 0.00 1.1 

I-Paraffins 2,4-Dimethyloctane 0.046 0.069 -0.02 0.7 

I-Paraffins 2,6-Dimethyloctane 0.179 0.215 -0.04 0.8 

I-Paraffins C10 Isoparaffin -1 0.047 0.054 -0.01 0.9 

I-Paraffins 3-Methyl-5-ethylheptane 0.067 0.123 -0.06 0.5 

I-Paraffins 5-Methylnonane 0.148 0.177 -0.03 0.8 

I-Paraffins 4-Methylnonane 0.25 0.245 0.01 1.0 

I-Paraffins 2-Methylnonane 0.283 0.24 0.04 1.2 

I-Paraffins 3-Ethyloctane 0.049 0.061 -0.01 0.8 

I-Paraffins 3-Methylnonane 0.286 0.273 0.01 1.0 

I-Paraffins Heptane, 2,2,3,5-tetramethyl­ 0.03 0.053 -0.02 0.6 

I-Paraffins C11-Isoparaffin-2 0.039 0.043 0.00 0.9 

I-Paraffins C10 - IsoParaffin - 5 0.045 0.075 -0.03 0.6 

I-Paraffins 2,3,3-trimethyloctane 0.026 0.046 -0.02 0.6 

I-Paraffins C11-Isoparaffin-3 0.022 0.033 -0.01 0.7 

I-Paraffins C11 Isoparaffin-4 0.075 0.079 0.00 0.9 

I-Paraffins C11-Isoparaffin-5 0.184 0.209 -0.03 0.9 

I-Paraffins 3-Ethylnonane 0.095 0.059 0.04 1.6 

I-Paraffins C11-Isoparaffin-6 0 0.035 -0.04 0.0 

I-Paraffins C11-Isoparaffin-7 0.099 0.113 -0.01 0.9 

I-Paraffins C11-Isoparaffin-8 0.045 0.039 0.01 1.2 

I-Paraffins C11-Isoparaffin-9 0.032 0.036 0.00 0.9 

I-Paraffins C11- Isoparaffin-11 0.11 0.063 0.05 1.7 

I-Paraffins C11- IsoParaffin - 13 0.13 0.057 0.07 2.3 

C12 - IsoParaffin - 1 0.009 0 0.01 NA 

Mono-Aromatics C12 - IsoParaffin - 2 0 0.004 0.00 0.0 

Mono-Aromatics C12 - IsoParaffin - 4 0 0.006 -0.01 0.0 

Mono-Aromatics Benzene 0.491 0.611 -0.12 0.8 

Mono-Aromatics Toluene 11.942 16.076 -4.13 0.7 

Mono-Aromatics Ethylbenzene 0.058 0.035 0.02 1.7 

Mono-Aromatics m-Xylene 0.171 0.186 -0.02 0.9 

Mono-Aromatics p-Xylene 0.06 0.06 0.00 1.0 

Mono-Aromatics o-Xylene 0.178 0.05 0.13 3.6 

B-2
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Original 

COLD CO 

Fuel 

New 

Cold CO 

Fuel 

EM-5574-F 

EM6802-F Original ­

New 

Original / 

New 

Group Component %Vol %Vol Difference, % Ratio 

Mono-Aromatics i-Propylbenzene 0.103 0.021 0.08 4.9 

Mono-Aromatics n-Propylbenzene 0.744 0.695 0.05 1.1 

Mono-Aromatics 1-Methyl-3-ethylbenzene 2.598 2.385 0.21 1.1 

Mono-Aromatics 1-Methyl-4-ethylbenzene 1.198 1.112 0.09 1.1 

Mono-Aromatics 1,3,5-Trimethylbenzene 1.411 1.438 -0.03 1.0 

Mono-Aromatics 1-Methyl-2-ethylbenzene 1.066 0.735 0.33 1.5 

Mono-Aromatics 1,2,4-Trimethylbenzene 4.311 3.419 0.89 1.3 

Mono-Aromatics i-Butylbenzene 0.09 0.093 0.00 1.0 

Mono-Aromatics 1,2,3-Trimethylbenzene 0.984 0.531 0.45 1.9 

Mono-Aromatics 1-Methyl-3-i-propylbenzene 0.038 0.024 0.01 1.6 

Mono-Aromatics 1-Methyl-4-i-propylbenzene 0.019 0.018 0.00 1.1 

Mono-Aromatics 1,3-Diethylbenzene 0.159 0.087 0.07 1.8 

Mono-Aromatics 1-Methyl-3-n-propylbenzene 0.402 0.254 0.15 1.6 

Mono-Aromatics 1-Methyl-4-n-propylbenzene 0.265 0.126 0.14 2.1 

Mono-Aromatics n-Butylbenzene 0.047 0.044 0.00 1.1 

Mono-Aromatics 1,3-Dimethyl-5-ethylbenzene 0.475 0.187 0.29 2.5 

Mono-Aromatics 1,2-Diethylbenzene 0.045 0.026 0.02 1.7 

Mono-Aromatics 1-Methyl-2-n-propylbenzene 0.173 0.098 0.08 1.8 

Mono-Aromatics C9 - Aromatic - 1 0.086 0.051 0.04 1.7 

Mono-Aromatics 1,4,Dimethyl-2-ethylbenzene 0.442 0.171 0.27 2.6 

Mono-Aromatics 1,3-Dimethyl-4-ethylbenzene 0.448 0.205 0.24 2.2 

Mono-Aromatics 1,2-Dimethyl-4-ethylbenzene 1.085 0.436 0.65 2.5 

Mono-Aromatics 1,3-Dimethyl-2-ethylbenzene 0.06 0.033 0.03 1.8 

Mono-Aromatics 1-Methyl-4-t-butylbenzene 0.013 0.035 -0.02 0.4 

1-Ethyl-3-i-propylbenzene 0.008 0 0.01 NA 

Mono-Aromatics 1,2-Dimethyl-3-ethylbenzene 0.127 0.141 -0.01 0.9 

Mono-Aromatics 1-Ethyl-4-i-propylbenzene 0.015 0.014 0.00 1.1 

Mono-Aromatics C11 - Aromatic - 1 0.009 0.014 -0.01 0.6 

Mono-Aromatics 1,2,4,5-Tetramethylbenzene 0.41 0.425 -0.02 1.0 

Mono-Aromatics 1,2,3,5-Tetramethylbenzene 0.781 0.606 0.18 1.3 

Mono-Aromatics C11 - Aromatic - 2 0 0.002 0.00 0.0 

Mono-Aromatics C11 - Aromatic - 3 0.015 0.066 -0.05 0.2 

Mono-Aromatics 1,2-Di-i-propylbenzene 0.021 0.074 -0.05 0.3 

Mono-Aromatics 1-methyl-4-(1-methylpropyl)be 0.039 0.109 -0.07 0.4 

Mono-Aromatics C11 - Aromatic - 4 0 0.051 -0.05 0.0 

Mono-Aromatics n-Pentylbenzene 0.006 0.023 -0.02 0.3 

Mono-Aromatics tert-Pentylbenzene 0.034 0.11 -0.08 0.3 

Mono-Aromatics 1-Methyl-2-n-butylbenzene 0.014 0.051 -0.04 0.3 

Mono-Aromatics C11 - Aromatic - 7 0.017 0.064 -0.05 0.3 

Mono-Aromatics 1,4-Di-i-propylbenzene 0.027 0.095 -0.07 0.3 

Mono-Aromatics C11 - Aromatic - 9 0.294 0.131 0.16 2.2 

Mono-Aromatics C11 - Aromatic - 10 0 0.011 -0.01 0.0 

Mono-Aromatics 1,3-Di-n-propylbenzene 0.027 0.067 -0.04 0.4 

Mono-Aromatics C11 - Aromatic - 11 0.016 0.038 -0.02 0.4 

B-3
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Original 

COLD CO 

Fuel 

New 

Cold CO 

Fuel 

EM-5574-F 

EM6802-F Original ­

New 

Original / 

New 

Group Component %Vol %Vol Difference, % Ratio 

Naphthalenes 1-ethyl-2,4,5-trimethylbenzen 0.014 0.02 -0.01 0.7 

Naphthalenes C11 - Aromatic - 13 0 0.003 0.00 0.0 

Naphtheno/OlefinoBenzs 2-Methylnaphthalene 0 0.006 -0.01 0.0 

Naphtheno/OlefinoBenzs 1-Methylnaphthalene 0 0.003 0.00 0.0 

C12 - Aromatic - 1 0.003 0 0.00 NA 

Indenes 5-Methylindan 0.134 0.209 -0.08 0.6 

Indenes 2-Methylindan 0.269 0.267 0.00 1.0 

Indenes Indan 0.262 0.235 0.03 1.1 

Indenes 2-Methylindan 0.088 0.034 0.05 2.6 

Indenes 

1H-Indene, 2,3-dihydro-1,2­

dim 0.012 0.007 0.01 1.7 

Indenes 4-Methylindan 0.12 0.273 -0.15 0.4 

Indenes 4,7-Dimethyl Indane 0.005 0.004 0.00 1.3 

Mono-Naphthenes 1,1-Dimethyl Indane 0.005 0.021 -0.02 0.2 

Mono-Naphthenes Dimethyl Indane - 1 0 0.005 -0.01 0.0 

Mono-Naphthenes Cyclopentane 0.449 0.452 0.00 1.0 

Mono-Naphthenes Methylcyclopentane 1.562 1.585 -0.02 1.0 

Mono-Naphthenes Cyclohexane 1.536 1.638 -0.10 0.9 

Mono-Naphthenes 1t,3-Dimethylcyclopentane 0.168 0.171 0.00 1.0 

Mono-Naphthenes 1c,3-Dimethylcyclopentane 0.152 0.157 -0.01 1.0 

Mono-Naphthenes 1t,2-Dimethylcyclopentane 0.268 0.271 0.00 1.0 

Mono-Naphthenes Methylcyclohexane 1.657 1.87 -0.21 0.9 

Mono-Naphthenes 1,1,3-Trimethylcyclopentane 0.04 0.04 0.00 1.0 

Mono-Naphthenes Ethylcyclopentane 0.055 0.06 -0.01 0.9 

Mono-Naphthenes 1c,2t,4-Trimethylcyclopentane 0.038 0.038 0.00 1.0 

Mono-Naphthenes 1t,2c,3-Trimethylcyclopentane 0.03 0.029 0.00 1.0 

Mono-Naphthenes 1,3-dimethyl-t-cyclohexane 0.164 0.183 -0.02 0.9 

Mono-Naphthenes 1,1-Dimethylcyclohexane 0.042 0.038 0.00 1.1 

Mono-Naphthenes 3c-Ethylmethylcyclopentane 0.01 0.008 0.00 1.3 

Mono-Naphthenes 3t-Ethylmethylcyclopentane 0.014 0.011 0.00 1.3 

Mono-Naphthenes 1c,4-Dimethylcyclohexane 0.045 0.044 0.00 1.0 

Mono-Naphthenes 1c,2-Dimethylcyclohexane 0.02 0.012 0.01 1.7 

Mono-Naphthenes Ethylcyclohexane 0.121 0.096 0.03 1.3 

Mono-Naphthenes 1c,2t,4t-Trimethylcyclohexane 0.062 0.032 0.03 1.9 

Mono-Naphthenes C9 - MonoNaph - 4 0.016 0.007 0.01 2.3 

Mono-Naphthenes 1c,2t,4c-Trimethylcyclohexane 0.014 0.012 0.00 1.2 

Mono-Naphthenes Cyclohexane, 1,2,4-trimethyl-, 0.02 0.02 0.00 1.0 

Mono-Naphthenes 

Cyclopentane, 1-methyl-2­

propyl­ 0.017 0.032 -0.02 0.5 

Mono-Naphthenes trans-1,3-Diethylcyclopentane 0.1 0.119 -0.02 0.8 

Mono-Naphthenes C10 - MonoNaph - 1 0 0.005 -0.01 0.0 

Mono-Naphthenes 1,1-Methylethylcyclohexane 0.078 0.136 -0.06 0.6 

Mono-Naphthenes 1-Methyl-2-propyl-cyclopentan 0.005 0.008 0.00 0.6 

B-4
 

 

 

 

 

 

 

 

 

 

 

 

 

Original 

COLD CO 

Fuel 

New 

Cold CO 

Fuel 

EM-5574-F 

EM6802-F Original ­

New 

Original / 

New 

Group Component %Vol %Vol Difference, % Ratio 

Mono-Naphthenes 1,2,3,5-t-Tetramethylcyclohex 0.141 0.198 -0.06 0.7 

Mono-Naphthenes 1,2,3,5-c-Tetramethylcyclohex 0 0.025 -0.03 0.0 

Mono-Naphthenes i-Butylcyclohexane 0.075 0.107 -0.03 0.7 

Mono-Naphthenes C10 - MonoNaph - 2 0.024 0.034 -0.01 0.7 

Mono-Naphthenes 

1t-Methyl-2-npropylcyclohexan 0 0.017 -0.02 0.0 

n-Olefins n-ButylCyclohexane 0.076 0.1 -0.02 0.8 

n-Olefins C11-MonoNaphthene-2 0.021 0.008 0.01 2.6 

t-Butene-2 0.003 0 0.00 NA 

c-Butene-2 0.004 0 0.00 NA 

Pentene-1 0.004 0 0.00 NA 

t-Pentene-2 0.012 0 0.01 NA 

c-Pentene-2 0.006 0 0.01 NA 

n-Olefins Hexene-1 2.812 4.587 -1.78 0.6 

n-Olefins t-Nonene-3 0 0.013 -0.01 0.0 

Iso-Olefins C10-n-Olefin 0.02 0.031 -0.01 0.6 

Iso-Olefins 3-Decene 0.009 0.018 -0.01 0.5 

5-Undecene 0.007 0 0.01 NA 

Iso-Olefins 3-Methyl-c-pentene-2 0 0.008 -0.01 0.0 

2-Methylbutene-1 0.008 0 0.01 NA 

2-Methylbutene-2 0.017 0 0.02 NA 

Iso-Olefins 3-Methyl-t-hexene-2 5.403 4.294 1.11 1.3 

Iso-Olefins C8 - Diolefin - 1 0.012 0.011 0.00 1.1 

Iso-Olefins 3-Heptene, 4-methyl­ 0.069 0.073 0.00 0.9 

Iso-Olefins C9 - IsoOlefin - 1 0.012 0.009 0.00 1.3 

Iso-Olefins 2,3-Dimethylheptene-2 0.016 0.023 -0.01 0.7 

Iso-Olefins C10 - IsoOlefin - 2 0.039 0.054 -0.02 0.7 

Iso-Olefins C10-IsoOlefin-4 0.006 0.009 0.00 0.7 

Iso-Olefins C10 Iso-olefin - 5 0.023 0.062 -0.04 0.4 

Iso-Olefins C10 Iso-olefin - 6 0.017 0.025 -0.01 0.7 

Iso-Olefins C10-IsoOlefin-7 0.053 0.076 -0.02 0.7 

Iso-Olefins C10 - IsoOlefin - 8 0 0.021 -0.02 0.0 

Iso-Olefins 2,3-Dimethyl-2-octene 0.013 0.03 -0.02 0.4 

Iso-Olefins C10-IsoOlefin-12 0.043 0.08 -0.04 0.5 

Naphtheno-Olefins C10-IsoOlefin -15 0.101 0.128 -0.03 0.8 

Naphtheno-Olefins 3-Nonene, 3-methyl-, (E)­ 0.014 0.03 -0.02 0.5 

Naphtheno-Olefins C8 - Naph-Olefin - 1 1.368 1.047 0.32 1.3 

1-Ethyl-2-Methylcyclopentene 0.036 0.02 0.02 1.8 

C9-NaphthenoOlefin-6 0 0 0.00 NA 

B-5
APPENDIX C 

LUBRIZOL LETTER REPORT 

LIGHT-DUTY HIGH PM EMISSIONS VEHICLE
 
 

 

 

 

 

 

June 9, 2008 

Mr. Lew Williams 

The Lubrizol Corporation 

29400 Lakeland Blvd. 

Wickliffe, OH 44092-2298 

lewis.williams@lubrizol.com 

Ref:	 Letter Report, "Selecting the High Smoke Emissions Vehicles," 

SwRI Project No. 03-11309. 

Dear Mr. Williams: 

The location, selection process for the candidate vehicles, and final decision to pick the 

‘high-emitting’ gasoline vehicle were performed by SwRI and approved in consultation with the 

members of the CLOSE and AVFL-14 projects. SwRI’s criteria for high-emitting vehicle was 

not based on make, model, type of owner, mileage, or any other a priori assumptions regarding 

the likelihood of any specific type of vehicle being a good candidate. With decades of emission 

regulations in place, and manufacturers producing extremely durable engine and exhaust control 

systems, SwRI recognizes that ‘smoking’ vehicles are not the norm in the existing fleet of 

operational vehicles; therefore, any vehicle selected is atypical. 

1.0 BACKGROUND 

According to the proposed scope of work the high-emitting gasoline vehicle was defined 

as “a gasoline-fueled vehicle with visible smoke related to lubrication oil. The RFP requests a 

PM emission rate greater than 200 mg/mi over the Unified Driving Cycle (UDC). In SwRI’s 

experience, vehicles that continually and consistently emit “white” smoke related to lubricating 

oil typically have PM emission rates well above this value (Whitney 2000, 1998). This vehicle 

will likely be solicited from SwRI employees, families, and friends. Candidate vehicles will be 

screened for visual indication of consistent “white” smoke emissions during a variety of driving 

conditions. Although the RFP states that there is no restriction on vehicle age or mileage, 

consideration will be given to the representativeness of the vehicle, as well as its ability to be 

safely and repeatably tested on a chassis dynamometer.” 

2.0 SOLICITATION 

The following notice was sent by email to all SwRI employees: 

C-1
 

WANTED: Smoking Car 

A project in the Office of Automotive Engineering requires a test car that emits visible 

smoke during all running conditions and needs frequent oil fills. Cars, half-ton pickups, and 

SUVs could be utilized. The vehicle should be in otherwise sound mechanical condition and 

driven regularly. We will pay the owner $500 plus provide an intermediate-size rental car for 

approximately 10 weeks. If you know of such a car and we choose to use it, a finder's fee of 

$100 is available. Contact Jim Carroll at 522-5015 or (mailto:jcarroll@swri.org). 

3.0 RESPONSES AND SELECTION PROCESS 

SwRI received 22 responses to the email solicitation. SwRI used the following selection 

criteria in generally descending order of importance to pick the high emitting test vehicle: 

1.	 Visible smoke upon hot start, at idle, during acceleration, and at steady speed. 

2.	 Relatively modern emission control system, i.e. equipped with exhaust catalyst, closedloop control, fuel injection. 

3.	 Automatic transmission. 

4.	 Stock engine, exhaust system, and drivetrain. 

5.	 Driven regularly. 

6.	 Fully operational drivetrain and brake system. 

7.	 No external engine oil leaks. 

8.	 None or easily repairable engine codes. 

9.	 Owner had good knowledge of vehicle history. 

10. Known high oil consumption. 

List of responses received and reasons for rejection of candidates: 

1998 Saturn SE2 Coupe – could not connect an ECM reader to the wiring harness without the 

horn on the vehicle blowing, symptom of wiring harness degradation or ECM problem. 

1988 Chevrolet Caprice – owned for just two weeks, not driven, fouled plugs within two weeks. 

1988 Chevrolet Camaro IROC – owner unresponsive. 

1995 Mitsubishi Eagle Talon – standard transmission. 

1963 Ford Fairlane – too old, produced prior to emissions controls. 

1993 Toyota Tercel – standard transmission. 

1995 Acura Integra – engine rebuilt once to high output configuration, then put back to original 

configuration. Not ‘stock.’ 

1986 Chevrolet truck – no catalyst. 

1994 Jeep Grand Cherokee – no catalyst. 

C-2
 

 

 

1995 Mitsubishi Eclipse – standard transmission. 

1995 Mitsubishi Eagle Talon – aftermarket performance exhaust and intake system, standard 

transmission. 

1995 Nissan 240SX – smoke visible upon acceleration only, no smoke at idle, startup, or at 

steady speed. Some oil seepage around head cover gasket.
 

1994 Mercury Cougar – owner unresponsive.
 

1998 Pontiac Gran Prix – some smoke at start, but not enough during steady-state operation.
 

1993 Mazda Protégé – standard transmission. 

1998 Mitsubishi Montero – standard transmission
 

1999 Dodge Neon – initially thought to be a good candidate, but found oil leaks at head cover
 

gasket and crankshaft main seal; also the engine had a mechanical knock.
 

1991 Acura – coolant leak, brakes unsafe, transmission shifted poorly, the engine shuddered.
 

Best candidate for recycling.
 

1990 Honda Accord – no smoke at idle, not enough smoke during acceleration. 

1999 Dodge Durango – smoke visible at idle only.
 

1990 Honda Accord – smoked if engine was revved, otherwise there was no smoke visible.
 

4.0 RECOMMENDED VEHICLE 

1993 Mercury Grand Marquis 

•	 Visible smoke upon hot and cold starts, at idle, during acceleration, and at steady 

speeds. 

•	 Relatively modern emission control system. 

•	 Automatic transmission. 

•	 Stock engine, exhaust system, and drivetrain. 

•	 Driven weekly. 

•	 Fully operational drivetrain and brake system. 

•	 No external engine oil leaks. 

•	 Engine code set was traced to EGR system. EGR lines were cleaned and controls 

were replaced. Codes were cleared and have not re-set since. 

•	 Owner had knowledge of complete vehicle history. 

C-3
 

 

 

 

 

 

The owners indicated that at approximately 30,000 miles they took it to the dealer due to 

what they believed was excessive oil consumption. The dealer conducted an oil consumption 

test and determined it to be approximately 1 quart every 1,200 miles. The dealer assured the 

owners that this was within normal specifications and that there was no problem with the vehicle. 

The owners noticed visible smoke at approximately 50,000 miles, and it has gotten progressively 

worse over the years. 

The vehicle has approximately 125,000 miles on the odometer and emits visible “blue” 

smoke during both cold and warm conditions. A set of preliminary four-phase Unified Cycle 

tests were conducted to evaluate the repeatability of this vehicle. Composite and phase-level 

particulate emission results are given in Table 1. Composite gaseous emission results are given 

in Table 2. These results indicate the test vehicle has relatively repeatable emissions and should 

meet the needs of this project. 

TABLE 1. FOUR-PHASE UNIFIED CYCLE PM EMISSION RATE, MG/MI 

Phase 1 Phase 2 Phase 3 Phase 4 Composite 

Test 1 31.2 77.3 133.6 130.3 101.1 

Test 2 41.4 79.5 133.9 142.9 108.3 

Test 3 35.8 61.7 156.7 118.8 91.0 

TABLE 2. COMPOSITE UNIFIED CYCLE PM EMISSION RATE, G/MI
 

THC CO NOX 

Test 1 0.55 6.6 1.7 

Test 2 0.70 8.1 1.7 

Test 3 0.66 7.3 1.7 

Due to concern regarding the failure mode of the this high PM emitter that SwRI 

recommended for testing, an effort was undertaken to evaluate and document the mechanical 

status of the vehicle as regards oil consumption. Evaluations included the following: 

•	 Spark plugs were removed, inspected, and photographed. 

•	 Each cylinder piston top, cylinder wall, and cylinder head was inspected and rated by 

borescope. 

•	 A compression and leak down check was performed on each cylinder. 

•	 Oil consumption was determined gravimetrically over 300 miles of highway operation. 

•	 The vehicle owner was contacted in an effort to get more detailed information regarding 

observed oil consumption for this vehicle. 

Figures 1 through 8 are photographs of the spark plugs pulled from the vehicle's engine. 

The numbering convention is cylinders/plugs 1-4 are front-to-back from the right cylinder bank 

if viewed from the driver, and plugs 5-8 are the left cylinder bank. The plugs did not appear to 

be fouled; they are dry, and some show electrode loss and unidentified white deposits. 

C-4
 

 

Figure 1. Spark Plug 1 Figure 2. Spark Plug 2 

Figure 3. Spark Plug 3 Figure 4. Spark Plug 4 

C-5
 

 

Figure 5. Spark Plug 5 Figure 6. Spark Plug 6 

Figure 7. Spark Plug 7 Figure 8. Spark Plug 8 

C-6
 

 

The results from the cylinder compression check, and leak down tests are shown in 

Tables 3, and 4, respectively. The compression test variation is good (within 10%) on the right 

bank but poor on the left bank. Cylinder leak down results are poor to bad (5-10% is good). The 

cylinders showed no sign of bore polishing or scuffing during the borescope inspection. 

TABLE 3. CYLINDER COMPRESSION TEST 

Right Cylinder Bank Left Cylinder Bank 

Cyl 1 130 psi Cyl 5 110 psi 

Cyl 2 140 psi Cyl 6 140 psi 

Cyl 3 130 psi Cyl 7 150 psi 

Cyl 4 130 psi Cyl 8 130 psi 

TABLE 4. CYLINDER LEAK DOWN TEST
 

Right Cylinder Bank Left Cylinder Bank 

Cyl 1 14% Cyl 5 28% 

Cyl 2 24% Cyl 6 28% 

Cyl 3 18% Cyl 7 14% 

Cyl 4 36% 

(Checked 2 times) 

Cyl 8 38% 

(Checked 2 times) 

SwRI completed the 300 mile oil consumption test. On 3/3/08, the vehicle was filled 

with the a preweighed amount of test oil and a new preweighed oil filter. The vehicle was 

operated for 457 miles. This included the 150 miles of highway driving at 65 to 70 mph, plus the 

chassis dyno testing presented in Tables 1 and 2. The oil consumption for the 457 miles was 

2.37 lbs of oil. On 4/21/08, the oil and used oil filter were drained and the weights recorded. 

The used oil and the used filter were reinstalled and the vehicle underwent another accumulation 

interval of 300 miles on the highway at 65 to 70 mph. On 4/24/08 the used oil and used filter 

were drained and the weights recorded. The oil consumption for the 300 miles was 1.85 lbs of 

oil. 

Using a density of 1.8 lb per quart of oil, the average oil consumption on the candidate 

smoking vehicle equates to 319 miles per quart. This is consistent with what was reported by the 

owner who stated that he has been adding 1 quart about every 300 miles. 

C-7
 

 

 

 

 

 

 

Lew Williams 

The Lubrizol Corp. 

June 9, 2008 

Page 8 of 8 

5.0 CLOSURE 

Following the completion of the smoking vehicle evaluation, all data was presented to the 

CLOSE/AVFL-14 team. The team recommended the use of the high emitting vehicle for the 

project. It is clear that this particular vehicle is atypical and not representative of this or any 

other make or model of on-highway high-mileage vehicle. 

Submitted by: Reviewed by: 

James N. Carroll Kevin A. Whitney 

Principal Engineer Manager 

Department of Emissions R&D Department of Emissions R&D 

Approved by: 

Jeff J. White 

Director 

Department of Emissions R&D 

/sat 
 

APPENDIX D
 

DESERT RESEARCH INSTITUTE REPORT ON RENO FUELS
 
TABLE D1. HOPANES AND STERANES IN FUELS FROM RENO 

NEVADA 

Hopanes and Steranes, ug/gram 

Reno Fuels 

Chevron 

Diesel 

Chevron 

Premium 

Chevron 

Regular Shell Diesel 

Shell 

Premium 

Shell 

Regular 

Texaco 

Diesel 

Texaco 

Premium 

Texaco 

Regular 

hop15 0.418 0.000 0.000 0.332 0.000 0.088 0.320 0.000 0.000 

hop17 0.720 0.111 0.132 0.743 0.106 0.039 0.609 0.097 0.122 

hop19 0.267 0.006 0.108 0.205 0.080 0.081 0.203 0.157 0.092 

hop20 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

hop21 0.081 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

hop22 0.158 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

hop23 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

hop24 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

hop25 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

hop26 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

hop27 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

ster42 0.161 0.000 0.000 0.223 0.000 0.000 0.158 0.000 0.000 

ster43 0.372 0.000 0.018 0.364 0.000 0.000 0.348 0.000 0.000 

ster44 0.225 0.000 0.000 0.191 0.000 0.000 0.206 0.000 0.000 

ster45_40 0.064 0.000 0.000 0.672 0.000 0.000 0.000 0.000 0.000 

ster46 0.038 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

ster47 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

ster48 0.000 0.000 0.000 0.000 0.000 0.000 0.221 0.000 0.000 

ster49 0.023 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 

ster50 0.000 0.000 0.000 0.000 0.000 0.000 0.031 0.000 0.000 

ster51 0.064 0.000 0.000 0.057 0.000 0.007 0.041 0.000 0.000 

ster52 0.022 0.000 0.000 0.044 0.000 0.039 0.000 0.000 0.000 

ster53 0.108 0.005 0.000 0.065 0.055 0.017 0.088 0.007 0.000 

D-1
D-2
 

APPENDIX E
	

HEAVY-DUTY SMOKER REPORT ON CPS VEHICLES
	
 

 

 

 

 

July 16, 2009 

Dr. Douglas R. Lawson 

National Renewable Energy Laboratory 

1617 Cole Boulevard 

Golden, CO 80401 

Email: Doug_Lawson@nrel.gov 

Subject: Heavy-Duty Diesel Candidate Vehicles for “CLOSE: Collaborative Lubricating 

Oil Study on Emissions” 

NREL Subcontract Number AEV-7-66409-01, SwRI Project No. 03.13012 

1.0 DISCUSSION 

SwRI was invited to inspect heavy-duty vehicles at City Public Service (CPS) Company, 

which is the electrical utility in the San Antonio area. The vehicles have been released from 

service and can be used in the CLOSE program as heavy-duty diesel PM emission test vehicles. 

Table 1 contains information regarding the vehicles we inspected. 

These vehicles were used as construction and repair support vehicles for CPS. All the 

vehicles are 1993 to 1998 models. Although many show low mileage accumulation, their 

engines were operated while the vehicle was at a stand still to power auxiliary systems such as 

lifts, winches, pumps, welders, etc. Thus the engines can have many more hours of operation 

than the vehicles. 

During our inspection of the vehicles each one was started and allowed to come to 

normal operating temperature for 5 to 10 minutes but they were not driven. During warm up the 

engine was quickly accelerated, operated at a few steady-state no-load points, and left to idle a 

few times. The exhaust plume from each vehicle was watched for smoke during operation and 

notes are included in Table 1. 

Three vehicles are candidates for use as high PM emission test vehicles. Vehicle #88153 

had clean engine exhaust upon start up but as the engine warmed up smoke was released. The 

exhaust smelled of lubricant, rather than diesel fuel, which indicates that its fuel system is 

operating normally and its oil control is compromised. Vehicle #88443 smoked upon start, 

during accelerations, and at elevated no-load speeds while cold, but did not smoke once the 

engine warmed. Vehicle #52159 showed slight smoke during start up and during accelerations, 

but none at idle. 

E-1
 

 

 

 

 

Table 1. Heavy-Duty Diesel Vehicle Inspections
	

VEHICLE NUMBER 

VEHICLE #88153 

HIGH PM EMISSION 

TEST CANDIDATE 

VEHICLE #88443 VEHICLE #52159 VEHICLE #88195 VEHICLE #98484 

VEHICLE #52183 

NORMAL PM 

EMISSION TEST 

CANDIDATE 

VEHICLE MODEL ’93 Ford F600 ’98 International 4700 

T444E ’94 Ford Type L90460 ’96 Ford 1996 F80350 International 4700 DT 466 Ford ’94 Type L9460 

VEHICLE TYPE Tow truck 5th Wheel truck 

MILEAGE 160,722 miles 39,558 miles 66,542 miles 79,843 miles 

AXLE Single axle Single axle Tandem axle Single axle Single axle Tandem axle 

ENGINE Ford 5.9L 403A, 

Model B5.9-160 

Navistar Model B175F 

7.3L, Family 

#WNVXH044FNA 

8.3L Ford 

Model C8.3-225 

Model A175 I-6 

466 c.i., 175 hp Cummins Engine 

GVW, LB 23,100 45,000 45,000 

VIN NUMBER #1FDWK64C5RCA2138 

4 

#1HTSCABL5WH55820 

9 #1FDYL90E8SVA19584 #1FDYF80E3TVA06230 #1FDYL90E3SCA19587 

NOTES Dead battery Good puff of smoke at 

start. 

Smoke on start, idles 

clean. 

Clean at start, then 

engine died, then black 

on restart. 

Dead battery Clean exhaust. 

No smoke at start and 

low idle. 

Good puff of smoke at tip 

in. Slight fog at tip in. Does not idle when cold. Wisp of smoke at startup. 

After warm up, there was 

plenty of smoke upon tip 

in, acceleration, and at 

high idle. 

Slight smoke at high idle, 

but none at low idle. 

Wisping smoke at idle 

“white” smoke. 

Some smoke (smells of 

diesel fuel) on first high 

idle rise. 

Smoke did not smell of 

diesel fuel, rather, it 

smelled of oil. 

After extended idle, very 

little smoke even at tip 

in. 

When warm, high idle 

exhaust was clean. 

Seems to misfire on tip 

in. 

Exhaust smells of fuel. 

Once warm, slight smoke 

haze, still smells like 

diesel. 

E-2
 

 

 

Vehicles #88195 and #98484 produced exhaust with a strong diesel smell indicating a 

problem with their fuel systems. 

2.0 TEST VEHICLE RECOMENDATIONS 

Vehicle #52183 did not smoke during startup, accelerations, or at higher speed no-load 

operation. SwRI recommends that this vehicle be used for the normal emitter heavy-duty diesel 

tests. 

For the high PM emitter tests, SwRI recommends that vehicle #88153 be utilized. It 

produced the greatest level of smoke and its exhaust did not smell of diesel fuel. 

3.0 CONCLUSION 

SwRI plans to test CNG fueled heavy-duty vehicles before HD diesel vehicles but has 

had difficulty locating them, and suspects that they may not be available by the time mediumduty vehicle testing is completed. Therefore, SwRI requests input from CLOSE project 

supporters regarding our recommendations for the HD diesel vehicle testing. We can then begin 

more detailed inspections of the vehicles in preparation for testing and move into the next phase 

of tests without interruption. 

Sincerely: 

James N. Carroll, Principal Engineer 

Light-Duty Vehicle Emissions Section 

Emissions Research and Development 

E-3