Acronyms and Abbreviations

3R

resurfacing, restoration, and rehabilitation

AADT

Annual Average Daily Traffic

AASHTO

American Association of State Highway and Transportation Officials

AMF

accident modification factor

Caltrans

California Department of Transportation

DDHV

design hourly volume for one direction

DOT

Department of Transportation

FHWA

Federal Highway Administration

HMA

hot mix asphalt

HMVMT

hundred million vehicle miles traveled

HOV

high occupancy vehicle

HSM

Highway Safety Manual

IHSDM

Interactive Highway Safety Design Model

ITS

intelligent transportation systems

km/h

kilometers per hour

mi/h

miles per hour

MUTCD

Manual of Uniform Traffic Control Devices

NCHRP

National Cooperative Highway Research Program

NHS

National Highway System

PCC

portland cement concrete

SPF

safety performance function

SR

State Route

TWLTL

two-way left-turn lane

vpd

vehicles per day