A Heavy-Duty Vehicle Visual Classification Scheme:

Heavy-Duty Vehicle Reclassification Method for Mobile Source Emissions Inventory Development

Prepared for CEE6792

Seungju Yoon

OUTLINE Background Objectives Current HDV classification schemes HDV weight regulation HDV manufacturers’ information Current methods of HDV reclassification A new HDV reclassification scheme Emissions rates analysis Uncertainties Recommendations

BACKGROUND

Atlanta highly depends goods movement (60% of consumer goods) on freight trucks emitting major mobile NOX and DPM, comparing to other metropolitan areas in U.S.

Air Quality agencies should develop accurate mobile source emissions inventory for regional air quality planning

Current HDV reclassification method (EPA) causes loosing the find resolution of the FHWA classes HDV on HPMS database

OBJECTIVES

Develop a new HDV reclassification method using GT visual HDV classification scheme and POLK data within 21 counties in Atlanta

Compare pollutant emissions rates from the new HDV reclassification method to them from EPA reclassification method

EPA HDV CLASSIFICATION (1)

Combination of growth vehicle weight ratings (GVWR) and fuel type (gasoline or diesel)

Sixteen HDV classesClasses 6 to 13 for gasoline vehiclesClasses 16 to 23 for diesel vehicles

EPA HDV CLASSIFICATION (2)

HDV Classes Abbreviation GVWR (1,000 lbs)

6/16 HDV2b 8.5 – 10.0

7/17 HDV3 – 14.0

8/18 HDV4 – 16.0

9/19 HDV5 – 19.5

10/20 HDV6 – 28.0

11/21 HDV7 – 33.0

12/22 HDV8a – 60.0

13/23 HDV8b > 60.0

FHWA HDV CLASSIFICATION (1)

Combination of the number of axles and tractor-trailer configurations

Nine HDV classes Single units (Class 5, two-axles, six-tires)Single units (Classes 6 to 7)Double units (Classes 8 to 10)Multiple units (Classes 11 to 13)

FHWA HDV CLASSIFICATION (2)

GT VISUAL HDV CLASSIFICATION Combination of the number of axles

and tractor-trailer configurations according to their horsepower ratings

Four HDV classes Class A (Single unit, two-axles)Class B (Single unit, +two-axles)Class C (Two units, three or four-axles)Class D (+two units, +four-axles)

FHWA HDV GVWR REGULATIONS A single axle: 20,000 lbs A tandem axle: 34,000 lbs Two axle HDV: 40,000 lbs Three axle HDV: 60,000 lbs Four axles and more HDV: 80,000 lbs

HDV MANUFACTURERS’ INFO (1)Gasoline HDV GVW GCW Axle

sTire

s

Light (pick-ups/vans)

10,000 - 2 4

Light (chassis-cabs/ cutaways)

15,000 - 2 6

Medium 34,000 60,000

2 6

Heavy 54,000 60,000

3

HDV MANUFACTURERS’ INFO (2)Diesel HDV GVW GCW Axle

sTire

s

Light (pick-ups/vans)

10,000 - 2 4

Light (chassis-cabs/ cutaways)

15,000 - 2 6

Medium 34,000 60,000 2 6

Heavy 64,000 80,000 3

CURRENT RECLASSIFICATION METHODS (1) EPA method

Combine all FHWA HDV classes and apportion EPA HDV classes according to these local or national VMT fractions

FHWA 5

FHWA 6

FHWA 7

FHWA ---

FHWA 5FHWA 6FHWA 7FHWA ---

EPA 6

EPA 7

EPA 17

EPA ---

VM

T

FR

AC

TIO

NS

HPM

S

DA

TA

BA

SE

CURRENT RECLASSIFICATION METHODS (2) National Cooperative Highway

Research Program (NCHRP) methodApply conversion factors, which were

developed from the national VMT fractions of FHWA classes, for FHWA HDV classes to EPA HDV classes or vise versa

VEHICLES FRACTIONS ON POLK DATA

Axle

Vehicle Type EPA Vehicle Classes (1,000 lbs)

10 14 16 19.5

26 33 60 >60

2 Chassis-cab 0.45

0.54

0.00

0.00

0.00

0.00

0.00

0.00

2 Incomplete VEH

0.38

0.38

0.16

0.02

0.05

0.00

- -

2 Incomplete P/U

0.98

0.02

- - - - - -

2,3 Straight truck 0.00

0.08

0.15

0.07

0.26

0.21

0.02

0.21

3 Tractor - - - 0.00

0.00

0.11

0.89

-

NEW RECLASSIFICATION METHOD - MAPPING CLASSES USING POLK DATAPOLK Vehicles EPA, GVWR (1,000 lbs)

10 14 16 19.5

26 33 60 >60

Chassis-cab

GT Classes A & BIncomplete VEH

Incomplete P/U

Straight truck

Tractor GT Classes C & D

MAPPING CONVRSION FACTORS

GT Classe

s

EPA Classes

6 7 --- 22 23

A & B 0.13231

0.11653

--- 0 0

C & D 0 0 --- 0.61846

0.30704

VEHICLE VOLUE COLLECTION (1)

VEHICLE VOLUE COLLECTION (2) Daily vehicle miles traveled on Interstates and

principal Arterials within 21 counties in Atlanta

GT Classes Interstates Principal Arterials

A & B 2,653,802 786,735

C & D 5,165,028 1,617,494

EMISSIONS RATE ESTIMATION (1)

13

6i

n

1jj,iB&Aii RL*Vol*CF*ErER

23

16k

n

1jj,kD&Ckk RL*Vol*CF*Er

ER = emissions rate (ton/day)Er = emissions rates from Mobile6 (g/mi-veh)CF = conversion factors from POLK dataVol = Vehicle volumesRL = roadway segment lengthsi = gasoline vehiclesj = road segments k = diesel vehicles

EMISSIONS RATE ESTIMATION (2)Pollutants GT Method

(ton/day)

EPA Method

(ton/day)

Change (%)

VOC 4.0 3.7 8.1

CO 45.6 60.0 - 24.0

NOX 172.3 146.2 17.9

PM2.5 3.0 2.5 20.0

UNCERTAINTIES

Regional vehicle registration distributions from POLK data may differ from the national registration distribution

The percentages of articulated straight trucks and tractors were not known

FHWA Class 5 may loose EPA Class HDV2b (GVWR, 10,000 lbs)

RECOMMENDATIONS AND FUTURE RESEARCH WORKS GT visual HDV classification scheme is

very useful to identify the HDV classes GT visual HDV scheme is the hybrid

scheme of EPA and FHWA HDV classification schemes

Fine tuning GT classes to EPA classes requires field data collection (GVWR by GT vehicle classes)

ACKNOWLEDGEMENT

Funded by Georgia Regional Transportation Authority

Co-authored with Peng Zhang, James R. Pearson, Randall L. Guensler, and Michael O. Rodgers in Air Quality Laboratory, Transportation Research Group

Be sent to AWMA conference in 2004