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HERS-ST Highway Economic Requirements System - State Version: Technical Report

August 2005

Table of Contents

Chapter 1: Introduction
1.1 HERS-ST Documentation
   1.1.1 User's Guide
   1.1.2 Overview
   1.1.3 Pilot Program Report
1.2 Technical Report

Chapter 2: An Outline of the Model Structure
2.1 The Process
2.2 Project Evaluation
2.3 HERS Submodels
2.4 Price
2.5 Benefits and Costs
2.6 HERS Analytical Objectives
2.7 The HERS Process/Scenarios
   2.7.1 The Improvement Selection Procedures
   2.7.2 Addressing Unacceptable Conditions
2.8 Implementation and Output
2.9 HERS Time Frames
2.10 Functional Classes
   2.10.1 HERS Functional Class Groups
   2.10.2 HERS-ST and Lower Functional Classes
2.11 The Fleet Composition Model
2.12 Policy Alternatives
   2.12.1 Funding Constraints
   2.12.2 Fuel Taxes
   2.12.3 Maximum Number of Lanes/High Cost Lanes

Chapter 3: Inputs
3.1 Section Data
   3.1.1 HPMS Sample Section Data Items
   3.1.2 User-Specified Improvements Data File
3.2 HERS Control and Parameter Variables
   3.2.1 The Preprocessor Control Inputs
   3.2.2 The HERS Control Inputs
   3.2.3 Parameter Inputs
      3.2.3.1 IMPRCOST.DAT - the Improvement Cost File
      3.2.3.2 DLTBLS.DAT - the Deficiency Levels File
      3.2.3.3 PARAMS.DAT - the Parameter File
         3.2.3.3.1 Pavement Improvement Parameters
         3.2.3.3.2 Truck Growth Factors
         3.2.3.3.3 Operating Cost Parameters
         3.2.3.3.4 Fuel Excise Tax Parameters
         3.2.3.3.5 Speed and Congestion Parameters
         3.2.3.3.6 Price Indices
         3.2.3.3.7 Pavement Deterioration Parameters
         3.2.3.3.8 Safety Parameters
         3.2.3.3.9 Travel Time Cost Parameters
         3.2.3.3.10 State Cost Factors
3.3 The HERS Preprocessor
   3.3.1 Validations
      3.3.1.1 Sections Skipped by HERSPP
      3.3.1.2 RURURB Validation
      3.3.1.3 Functional Class Validation
      3.3.1.4 Maximum Traffic Growth Rate
      3.3.1.5 Curves and Grades
      3.3.1.6 Speed Limit
      3.3.1.7 K and D Factors
      3.3.1.8 Percent Green Time
      3.3.1.9 Traffic Control Devices per Mile
      3.3.1.10 Turning Lanes
      3.3.1.11 Signalization Validation and Override
   3.3.2 Default Values
      3.3.2.1 Default Values for Unpaved Sections
      3.3.2.2 Other Default Values
   3.3.3 Calculated Values
      3.3.3.1 SN or D
      3.3.3.2 Pavement Section
      3.3.3.3 ESALs Prior to the Base Year
      3.3.3.4 Time and PSR of Last Pavement Improvement
      3.3.3.5 Weighted Design Speed
      3.3.3.6 Capacity
      3.3.3.7 Traffic Growth Rates
         3.3.3.7.1 Option One - Concave Geometric Growth
         3.3.3.7.2 Option Two - Linear Growth
         3.3.3.7.3 Option Three - Convex Geometric Growth
         3.3.3.7.4 Additional Growth Rate Considerations
      3.3.3.8 Geometric Values
      3.3.3.9 Horizontal and Vertical Alignment Adequacy
      3.3.3.10 Peak Percent Trucks
      3.3.3.11 Urban Freeways
      3.3.3.12 Geometrics Following Alignment Improvement
      3.3.3.13 Wet
      3.3.3.14 Parameters for Delay Calculations
   3.3.4 Conversions
      3.3.4.1 Percentage Conversions
      3.3.4.2 County Code Conversion
      3.3.4.3 Shoulder Type Code Conversion
      3.3.4.4 Surface Type Code Conversion
      3.3.4.5 Metric to English Conversion
      3.3.4.6 IRI to PSR Conversion
   3.3.5 Processing the User-Specified Improvements File

Chapter 4: Design of Improvement Alternatives
4.1 The Override Mode and User-Specified Improvements
   4.1.1 User-Specified Improvements
   4.1.2 Evaluations of Individual Improvements
   4.1.3 Benefits and Costs
      4.1.3.1 Improvement Costs
      4.1.3.2 User Benefits
4.2 HERS-Designed Improvements
   4.2.1 Deficiency Criteria
   4.2.2 Default Deficiency Criteria
      4.2.2.1 Deficiency Levels
      4.2.2.2 Serious Deficiency Levels
      4.2.2.3 Unacceptability Levels
   4.2.3 HERS Improvement Types and Kinds
      4.2.3.1 Identifying Improvements for Analysis
      4.2.3.2 Addressing Ordinary Deficiencies: the Second Pass
      4.2.3.3 Aggressive Improvement Types
      4.2.3.4 Less Aggressive Alternatives
      4.2.3.5 Addressing Unacceptable Conditions: the Optional First Pass
      4.2.3.6 Determining the Number of Lanes to Add
         4.2.3.6.1 Design Year Lane Requirements
         4.2.3.6.2 Additional Lane Options
         4.2.3.6.3 Examples of Lane Option Logic
   4.2.4 Effects of HERS Improvements
      4.2.4.1 The Effects of Improvements on Pavement Thickness
         4.2.4.1.1 Reconstruction
         4.2.4.1.2 Simple Resurfacing
         4.2.4.1.3 Resurfacing with Widening Improvements
      4.2.4.2 The Effects of Improvements on Structural Number
      4.2.4.3 The Effects of Improvements on PSR
      4.2.4.4 The Effects of Alignment Improvements on Pavement Characteristics
      4.2.4.5 Correcting Substandard Conditions on Urban Freeways
4.3 The Widening Feasibility Model
4.4 The Capacity Model
   4.4.1 Capacity
   4.4.2 Effects of Capacity Improvements

Chapter 5: Estimation of Impacts
5.1 The Pavement Deterioration Model
   5.1.1 Equivalent Single-Axle Loads
   5.1.2 Pavement Condition
      5.1.2.1 Flexible Pavement
      5.1.2.2 Rigid Pavement
      5.1.2.3 Minimum Deterioration Rate
      5.1.2.4 Maximum Deterioration Rate
      5.1.2.5 Minimum PSR Level
5.2 Estimating Operating Costs
   5.2.1 Operating Cost Components
      5.2.1.1 Component Prices
      5.2.1.2 Adjustment Factors for Consumption Rates
         5.2.1.2.1 Fuel Efficiency Adjustment Factor
         5.2.1.2.2 Oil Consumption Adjustment Factor
         5.2.1.2.3 Depreciation Rate Adjustment Factor
   5.2.2 Constant-Speed Operating Costs
   5.2.3 The Effect of Speed-Change Cycles
   5.2.4 The Effect of Curves
      5.2.4.1 Sections With AES Below 55 M.P.H
      5.2.4.2 Sections with AES Above 55 M.P.H
   5.2.5 Total Operating Costs
5.3 Safety Costs
   5.3.1 Crash Rates
      5.3.1.1 Rural Two-Lane Roads
         5.3.1.1.1 Non-intersection Crashes
         5.3.1.1.2 Intersection Crashes
      5.3.1.2 Rural Multilane Roads
      5.3.1.3 Rural Freeways
      5.3.1.4 Urban Freeways
      5.3.1.5 Urban Multilane Surface Streets
      5.3.1.6 Urban Two-Lane Streets
      5.3.1.7 Calibration
   5.3.2 Fatalities and Injuries
   5.3.3 Secular Trends
   5.3.4 Costs of Crashes
      5.3.4.1 Unit Costs of Crashes in 1994
      5.3.4.2 Indexing the Costs of Crashes
5.4 The HERS Speed Model
   5.4.1 Free-Flow Speed and the APLVM
      5.4.1.1 Calculating the Effect of Curves
      5.4.1.2 Estimating Velocity Limited by Pavement Roughness
      5.4.1.3 Estimating Velocity Limited by Speed Limits
      5.4.1.4 Determining Free-Flow Speed
   5.4.2 The Effects of Grades on Free-Flow Speed
   5.4.3 Delay Due to Congestion and Traffic Control Devices
      5.4.3.1 Sections with Stop Signs
      5.4.3.2 Sections with Traffic Signals
      5.4.3.3 Sections With Stop Signs and Traffic Signals
      5.4.3.4 Free-Flow Sections, One Lane per Direction
      5.4.3.5 Free-Flow Sections, Three-Lane Two-Way
      5.4.3.6 Free-Flow Sections, Two or More Lanes per Direction
   5.4.4 Distance Traveled Between Traffic Control Devices
5.5 Travel Time Costs
   5.5.1 Vehicle Occupants
   5.5.2 Average Vehicle Occupancy
   5.5.3 Personal-Use Percentage of VMT
   5.5.4 Vehicle Costs
   5.5.5 Inventory Costs
   5.5.6 Estimating Travel Time Costs
5.6 The Travel Forecast Model
   5.6.1 Initialization: Assuming the Baseline Price
   5.6.2 Applying Elasticity to Travel Volume Forecasts
   5.6.3 The Simultaneous Solution
   5.6.4 Computational Algorithms
   5.6.5 Delay Equations by Road Type
5.7 Agency Costs and Benefits
   5.7.1 Maintenance Costs for Flexible Pavements
   5.7.2 Maintenance Costs for Rigid Pavements
5.8 External Costs

Chapter 6: Capital Cost of Improvements
6.1 The Length of an Improvement
6.2 Pavement and Widening Improvements
   6.2.1 Resurfacing Pavement
   6.2.2 Resurfacing Pavement with Shoulder Improvements
   6.2.3 Resurfacing Pavement and Widening Lanes
   6.2.4 Resurfacing Pavement and Adding Normal Cost Lanes
   6.2.5 Resurfacing Pavement and Adding High Cost Lanes
   6.2.6 Reconstructing Pavement
   6.2.7 Reconstructing Pavement and Widening Lanes
   6.2.8 Reconstructing Pavement and Adding Normal Cost Lanes
   6.2.9 Reconstructing Pavement and Adding High Cost Lanes
6.3 Calculating Alignment Costs
6.4 Total Improvement Cost
6.5 Allocating Capacity and Preservation Costs
6.6 State Cost Factors

Chapter 7: Evaluating Improvements
7.1 Cost and Benefit Calculations
   7.1.1 Improvement Selection Procedures
7.2 The Base Case
7.3 Determining the Benefit-Cost Analysis Period
7.4 Estimating Variable Costs for the Base Case
7.5 Determining Costs Associated with the Candidate Improvement
7.6 Determining the Capital Costs of the Improvements
7.7 Residual Value
   7.7.1 Possible Biases From Using RSL
   7.7.2 An RSL Example
7.8 The Benefit-Cost Ratio
   7.8.1 Consumer Surplus
   7.8.2 Discounting and Summation
7.9 Does a Section Warrant Improvement?
7.10 Selecting Improvements
7.11 Improvement Selection Without Mandatory Improvements
   7.11.1 Minimum BCR Analysis
   7.11.2 Constrained Analysis
7.12 Selecting Mandatory Improvements
   7.12.1 Unacceptable Conditions and the Constrained Fund Run
   7.12.2 Unacceptable Conditions and the Performance Constrained Run
   7.12.3 Unacceptable Conditions and the Minimum BCR Run
7.13 User-Specified Improvements
   7.13.1 Improvement Costs
   7.13.2 User Benefits

Chapter 8: Model Output
8.1 Printed Output
   8.1.1 The System Conditions Output Format
   8.1.2 The Deficiency Summary Output Format
   8.1.3 The "By Improvement Type" Output Format
      8.1.3.1 The Total Initial Cost of Selected Improvements
      8.1.3.2 Initial Cost of Preservation Improvements
      8.1.3.3 Initial Cost of Capacity Improvements
      8.1.3.4 Lane-Miles Improved
      8.1.3.5 Lane-Miles of Mandatory Improvements Selected on a Priority Basis To Address Unacceptable Conditions
      8.1.3.6 Lane-Miles of Non-Mandatory Improvements Not Selected on a Priority Basis
      8.1.3.7 The Net Present Value of the Residual Value of All Improvements
      8.1.3.8 The Average Benefit-Cost Ratio of Selected Improvements
      8.1.3.9 Total Benefits in the Last Year Of The Period
      8.1.3.10 Maintenance Costs Savings in the Last Year Of The Period
      8.1.3.11 User Benefits in the Last Year Of The Period
      8.1.3.12 Travel Time Savings in the Last Year Of The Period
      8.1.3.13 Operating Cost Savings in the Last Year Of The Period
      8.1.3.14 Safety Benefits in the Last Year Of The Period
      8.1.3.15 Crashes Avoided in the Last Year Of The Period
      8.1.3.16 Injuries Avoided in the Last Year Of The Period
      8.1.3.17 Lives Saved in the Last Year Of The Period
      8.1.3.18 VMT For Improved Sections in the Last Year Of The Period
      8.1.3.19 Emissions Costs Savings in the Last Year of the Period
      8.1.3.20 Miles Improved
      8.1.3.21 Miles of Mandatory Improvements Selected on a Priority Basis To Address Unacceptable Conditions
      8.1.3.22 Miles of Non-Mandatory Improvements Not Selected on a Priority Basis
      8.1.3.23 Lane-Miles Added to the System through Widening Improvements
   8.1.4 The "By IBCR" Output Format
8.2 Comma-Delimited Files
8.3 Section Output Files

Appendix A: Default Deficiency Criteria Tables

Appendix B: Induced Traffic and Induced Demand
B.1 Concepts of Induced Demand
   B.1.1 Exogenous Demand Factors
   B.1.2 Demand Fills Capacity
   B.1.3 Elastic Demand
B.2 Short Run versus Long Run
   B.2.1 Short-Run Elasticity
   B.2.2 Long-Run Elasticity
   B.2.3 Induced Traffic versus Induced Demand
   B.2.4 Disaggregation of Long Run Elasticity
B.3 Induced Traffic
   B.3.1 Partial and General Equilibrium Demand Curves
   B.3.2 "Gross" versus "Net" Induced Traffic
   B.3.3 Schedule Delay and Peak Shifting
B.4 Induced Demand
   B.4.1 Baseline Demand Forecast
   B.4.2 Breaking the Forecast Into Discrete Periods
   B.4.3 Long Run Shifts in the Demand Curve
   B.4.4 Getting to the Long Run
   B.4.5 Empirical Estimates of Short and Long Run Elasticities
   B.4.6 Interpreting Demand Forecasts
B.5 Summary
B.6 References

Appendix C: Demand Elasticities for Highway Travel
C.1 Theory
   C.1.1 The Meaning of Elasticity
      C.1.1.1 Transferability
      C.1.1.2 Price, Output, and Market
      C.1.1.3 Money Price
   C.1.2 Generalized Price and Its Components
      C.1.2.1 Sum of the Components of Price
      C.1.2.2 A More General Case
   C.1.3 Three Relationships: Component Elasticity, Shrinkage, and Overall Elasticity
      C.1.3.1 Price Elasticity for a Component
      C.1.3.2 Shrinkage of the Component
      C.1.3.3 Expansion From Component to Total Elasticity
C.2 Empirical Estimation of Price Components
   C.2.1 From Evidence to Application
   C.2.2 Construction of Travel Demand Elasticities from User Cost Components
   C.2.3 Define User Cost Components
   C.2.4 Estimates of Component Shares
   C.2.5 Determine Which Components Are Included in the "Price"
   C.2.6 Component Shares of Total User Cost
   C.2.7 Empirical Estimates of Own-Price Elasticities
   C.2.8 Magnitudes of the Shrinkages
   C.2.9 Durations of the Short-and Long-Run Adjustment Periods
C.3 Conversion to Generalized Price Elasticity
   C.3.1 Fuel Price Elasticities
   C.3.2 Ownership Elasticity
   C.3.3 Toll Elasticities
   C.3.4 Parking Price Elasticities
   C.3.5 Time Cost Elasticities
C.4 Adjustment from Total to Section Elasticities
   C.4.1 Occupancy
   C.4.2 Section Length
   C.4.3 Route Diversion
   C.4.4 Time-of-day Diversion (Peak Spreading)
C.5 Conclusions
C.6 References

Appendix D: Basic Theory of Highway Project Evaluation
D.1 Project Description
   D.1.1 Marginal Cost
   D.1.2 Average Cost
   D.1.3 Price
   D.1.4 Constructing the Demand Curve
   D.1.5 Project Alternatives
D.2 Single-Period Evaluation
   D.2.1 Short-Run Effects of Improvements
   D.2.2 Incremental Net Benefits
   D.2.3 NOB Based on Marginal Cost
   D.2.4 NOB Based on AVC
   D.2.5 "Old" versus "New" Trips
   D.2.6 NOB with Price Below AVC
D.3 Components of Net Operating Benefit
   D.3.1 Savings on Old Trips
   D.3.2 Incremental Consumer Surplus
   D.3.3 Producer Surplus on New Trips
   D.3.4 External Costs
   D.3.5 Externalities in Related Markets
D.4 Multi-Period Evaluation
   D.4.1 Breaking the Project Life Into Discrete Demand Periods
   D.4.2 Growth in Demand
D.5 Summary
D.6 A Numerical Example
D.7 References

Appendix E: Operating Cost Equations
E.1 Sources of HERS Operating Cost Equations
   E.1.1 Region of Interest
   E.1.2 Updating of Operating Cost Equations
      E.1.2.1 Determining Which Equations Required Updating
      E.1.2.2 Method and Tools Employed
      E.1.2.3 Notable Exception: 3-4 Axle Combination Unit Trucks
      E.1.2.4 Notable Exception: 5+ Axle Combination Unit Trucks
E.2 The Operating Cost Equations
E.3 Small Automobile
   E.3.1 Constant-Speed Fuel Consumption (CSFC)
   E.3.2 Constant-Speed Oil Consumption (CSOC)
   E.3.3 Constant-Speed Tire Wear (CSTW)
   E.3.4 Constant-Speed Maintenance and Repair (CSMR)
   E.3.5 Constant-Speed Depreciation (CSVD)
   E.3.6 Excess Fuel Consumption Due to Speed Variability (SCCFC)
   E.3.7 Excess Oil Consumption Due to Speed Variability (SCCOC)
   E.3.8 Excess Tire Wear Due to Speed Variability (SCCTW)
   E.3.9 Excess Maintenance and Repair Due to Speed Variability (SCCMR)
   E.3.10 Excess Depreciation Due to Speed Variability (SCCD)
   E.3.11 Excess Fuel Consumption Due to Curves (CFC)
   E.3.12 Excess Tire Wear Due to Curves (CTW)
   E.3.13 Excess Maintenance and Repair Due to Curves
E.4 Medium/Large Automobile
   E.4.1 Constant-Speed Fuel Consumption (CSFC)
   E.4.2 Constant-Speed Oil Consumption (CSOC)
   E.4.3 Constant-Speed Tire Wear (CSTW)
   E.4.4 Constant-Speed Maintenance and Repair (CSMR)
   E.4.5 Constant-Speed Depreciation (CSVD)
   E.4.6 Excess Fuel Consumption Due to Speed Variability (SCCFC)
   E.4.7 Excess Oil Consumption Due to Speed Variability (SCCOC)
   E.4.8 Excess Tire Wear Due to Speed Variability (SCCTW)
   E.4.9 Excess Maintenance and Repair Due to Speed Variability (SCCMR)
   E.4.10 Excess Depreciation Due to Speed Variability (SCCD)
   E.4.11 Excess Fuel Consumption Due to Curves (CFC)
   E.4.12 Excess Tire Wear Due to Curves (CTW)
   E.4.13 Excess Maintenance and Repair Due to Curves
E.5 4-Tire Trucks
   E.5.1 Constant-Speed Fuel Consumption (CSFC)
   E.5.2 Constant-Speed Oil Consumption (CSOC)
   E.5.3 Constant-Speed Tire Wear
   E.5.4 Constant-Speed Maintenance and Repair
   E.5.5 Constant-Speed Depreciation (CSVD)
   E.5.6 Excess Fuel Consumption Due to Speed Variability (SCCFC)
   E.5.7 Excess Oil Consumption Due to Speed Variability (SCCOC)
   E.5.8 Excess Tire Wear Due to Speed Variability (SCCTW)
   E.5.9 Excess Maintenance and Repair Due to Speed Variability (SCCMR)
   E.5.10 Excess Depreciation Due to Speed Variability (SCCD)
   E.5.11 Excess Fuel Consumption Due to Curves (CFC)
   E.5.12 Excess Tire Wear Due to Curves (CTW)
   E.5.13 Excess Maintenance and Repair Due to Curves
E.6 6-Tire Truck
   E.6.1 Constant-Speed Fuel Consumption (CSFC)
   E.6.2 Constant-Speed Oil Consumption (CSOC)
   E.6.3 Constant-Speed Tire Wear (CSTW)
   E.6.4 Constant-Speed Maintenance and Repair (CSMR)
   E.6.5 Constant-Speed Depreciation (CSVD)
   E.6.6 Excess Fuel Consumption Due to Speed Variability (SCCFC)
   E.6.7 Excess Oil Consumption Due to Speed Variability (SCCOC)
   E.6.8 Excess Tire Wear Due to Speed Variability (SCCTW)
   E.6.9 Excess Maintenance and Repair Due to Speed Variability (SCCMR)
   E.6.10 Excess Depreciation Due to Speed Variability (SCCD)
   E.6.11 Excess Fuel Consumption Due to Curves (CFC)
   E.6.12 Excess Tire Wear Due to Curves (CTW)
   E.6.13 Excess Maintenance and Repair Due to Curves
E.7 3+ Axle Single-Unit Truck
   E.7.1 Constant-Speed Fuel Consumption (CSFC)
   E.7.2 Constant-Speed Oil Consumption (CSOC)
   E.7.3 Constant-Speed Tire Wear (CSTW)
   E.7.4 Constant-Speed Maintenance and Repair (CSMR)
   E.7.5 Constant-Speed Depreciation (CSVD)
   E.7.6 Excess Fuel Consumption Due to Speed Variability (SCCFC)
   E.7.7 Excess Oil Consumption Due to Speed Variability (SCCOC)
   E.7.8 Excess Tire Wear Due to Speed Variability (SCCTW)
   E.7.9 Excess Maintenance and Repair Due to Speed Variability (SCCMR)
   E.7.10 Excess Depreciation Due to Speed Variability (SCCD)
   E.7.11 Excess Fuel Consumption Due to Curves (CFC)
   E.7.12 Excess Tire Wear Due to Curves (CTW)
   E.7.13 Excess Maintenance and Repair Due to Curves
E.8 3-4 Axle Combination Unit Truck
   E.8.1 Constant-Speed Fuel Consumption (CSFC)
   E.8.2 Constant-Speed Oil Consumption (CSOC)
   E.8.3 Constant-Speed Tire Wear (CSTW)
   E.8.4 Constant-Speed Maintenance and Repair (CSMR)
   E.8.5 Constant-Speed Depreciation (CSVD)
   E.8.6 Excess Fuel Consumption Due to Speed Variability (SCCFC)
   E.8.7 Excess Oil Consumption Due to Speed Variability (SCCOC)
   E.8.8 Excess Tire Wear Due to Speed Variability (SCCTW)
   E.8.9 Excess Maintenance and Repair Due to Speed Variability (SCCMR)
   E.8.10 Excess Depreciation Due to Speed Variability (SCCD)
   E.8.11 Excess Fuel Consumption Due to Curves (CFC)
   E.8.12 Excess Tire Wear Due to Curves (CTW)
   E.8.13 Excess Maintenance and Repair Due to Curves
E.9 5+ Axle Combination Unit Truck
   E.9.1 Constant-Speed Fuel Consumption (CSFC)
   E.9.2 Constant-Speed Oil Consumption (CSOC)
   E.9.3 Constant-Speed Tire Wear (CSTW)
   E.9.4 Constant-Speed Maintenance and Repair (CSMR)
   E.9.5 Constant-Speed Depreciation (CSVD)
   E.9.6 Excess Fuel Consumption Due to Speed Variability (SCCFC)
   E.9.7 Excess Oil Consumption Due to Speed Variability (SCCOC)
   E.9.8 Excess Tire Wear Due to Speed Variability (SCCTW)
   E.9.9 Excess Maintenance and Repair Due to Speed Variability (SCCMR)
   E.9.10 Excess Depreciation Due to Speed Variability (SCCD)
   E.9.11 Excess Fuel Consumption Due to Curves (CFC)
   E.9.12 Excess Tire Wear Due to Curves (CTW)
   E.9.13 Excess Maintenance and Repair Due to Curves
E.10 Pavement Condition Adjustment Factors
   E.10.1 Constant-Speed Fuel and Oil Consumption (PCAFOC)
   E.10.2 Constant-Speed Tire Wear (PCAFTW)
   E.10.3 Constant-Speed Maintenance and Repair (PCAFMR)
   E.10.4 Constant-Speed Depreciation (PCAFVD)

Appendix F: Procedures for Estimating Air Pollution Costs
F.1 Overview
   F.1.1 How Improvements Affect Air Pollution Costs
   F.1.2 Critical Assumptions
F.2 Estimating Air Pollutant Emissions
   F.2.1 Specific Pollutants Considered
   F.2.2 Emission Rates for HERS Vehicle Classes and Section Types
   F.2.3 Future Trends in Emission Rates
   F.2.4 Final Emission Rates
F.3 Air Pollution Damage Costs
   F.3.1 Damage Costs for Individual Air Pollutants
   F.3.2 Adjustments to Per-Ton Damage Costs
   F.3.3 Air Pollution Costs per Vehicle-Mile
   F.3.4 Assessing the Effect of Proposed Improvements on Air Pollution Costs
   F.3.5 Likely Effects of Including Air Pollution Costs

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Updated: 02/14/2013