U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590

Skip to content

FHWA Resource Center

FHWA Home / Resource Center / Planning and Air Quality Team / Resources

Planning and Air Quality

Project Level Analysis Table

Criteria for Evaluating Project
PM (PM10 and PM2.5)
Regulatory Basis
NEPA, Conformity Rule
NEPA, PM Hotspot Conformity Rule
State Regulation only
No Federal regulations for GHG
Criteria defining analysis approach
Defined by EPA, FHWA 1986 Memo
AADT, diesel % of fleet
AADT, diesel % of fleet, receptor distance
Defined by State
Variables, thresholds used to select analysis approach
AADT Volume
Defined by LOS?
125, 000
140, 000 – 150, 000
Defined by State
Is AADT or LOS a better criteria? IAC Consultation
Percent Diesel Traffic
Not defined
High diesel volumes (>8% ?)
Defined by State
Defined by IAC Consultation
Receptor Sensitivity or Population Proximity
30 feet from pavement
Not defined
Proximity to population areas (300 feet from roadway ?)
Defined by State
Defines human or instrument serving as human surrogate
Other Considerations
Urban Background Concentration
Defined in EPA Guidance, FHWA Memo
Indirectly considered; Qualitative analysis suggests comparisons with monitors which may or may not represent background
Not Defined
Not Defined
Urban background concentration only relevant for comparison with measured concentration
Definition of Project Boundary
Not Defined
Not Defined
Not Defined
Not Defined
Defined by % AADT change, other?
Analysis Methods
Qualitative, Quantitative (concentration oriented)
Qualitative, Quantitative (inventory oriented)
Dependent on State, typically mass or energy consumption oriented
Methods defined in Guidance documents; MOBILE/MOVES for EF; CAL3QHC for concentrations


Page last modified on June 5, 2017
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000