Human Factors Guidelines for Road Systems: Third Edition (2025)
Chapter: 31 Abbreviations
CHAPTER 31
Abbreviations
Δt |
sampling interval |
AARP |
American Association of Retired Persons |
ABS |
anti-lock braking system |
ADT |
average daily traffic |
APL |
arrow-per-lane (sign) |
APS |
accessible pedestrian signals |
ASD |
available sight distance |
ATIS |
Advanced Traveler Information Systems |
BCT |
bicycle crossing time |
BD |
braking distance |
BMG |
bicycle minimum green time |
BRT |
base reading time |
Caltrans |
California Department of Transportation |
cd |
candela |
CIE |
Commission Internationale de lʼEclairage |
cm |
centimeter(s) |
CMF |
crash modification factors |
CMS |
changeable message signs |
CPM |
crash prediction model |
CSS |
context sensitive solutions |
DPM |
driver performance model |
DSD |
decision sight distance |
DVRE |
driver, vehicle, roadway, and environment |
EL |
edge lines |
FARS |
Fatal Accident Reporting System |
FYA |
flashing yellow arrow |
HFG |
Human Factors Guidelines |
HFIM |
Human Factors Interaction Matrix |
HFST |
high-friction surface treatment |
HOV |
high-occupancy vehicle |
HPS |
high-pressure sodium (lamp) |
IA |
Intersection angles |
IHSDM |
Interactive Highway Safety Design Model |
ISD |
intersection sight distance |
ITE |
Institute of Transportation Engineers |
ITS |
Intelligent Transportation System |
km/h |
kilometers per hour |
LBI |
leading bicycle interval |
LC |
lane change |
LD |
legibility distance |
LED |
light-emitting diode |
LongROAD |
Longitudinal Research on Aging Drivers |
LOS |
level of service |
LPI |
leading pedestrian interval |
LPS |
low-pressure sodium (lamp) |
m |
meter |
mcd |
millicandela |
MH |
metal halide |
mi |
mile |
mi/h |
miles per hour |
mm |
millimeter |
MMI |
most meaningful information |
MT |
maneuver time |
MUTCD |
Manual on Uniform Traffic Control Devices |
NACTO |
National Association of City Transportation Officials |
NHTSA |
National Highway Traffic Safety Administration |
N•m |
newton meter |
NMSL |
National Maximum Speed Limit |
NTOR |
no turn on red |
PATH |
Partners for Advanced Transit and Highways |
PC |
point of curvature |
PCC |
Portland cement concrete |
PHB |
pedestrian hybrid beacon |
PIEV |
perception-identification-emotion-volition |
PMD |
post-mounted delineator |
POV |
principal other vehicle |
PPE |
personal protective equipment |
PRT |
perception-reaction time |
PSD |
passing sight distance |
PVSD |
preview sight distance |
R value |
correlation-coefficient |
ROW |
right-of-way |
RPM |
raised pavement marker |
RRFB |
rectangular rapid flashing beacon |
RPM |
raised pavement marker |
RRPM |
raised retroreflective pavement marker |
RT |
reaction time |
RTOR |
right turn on red |
s |
second(s) |
SAE |
Society of Automotive Engineers |
SBBL |
shared bus-bicycle lanes |
SCL |
speed-change lane |
SD |
sight distance |
SDHAZ |
sight distance to hazard |
SF |
safety factor |
SI |
International System of Units |
SLIDE |
simplified location of information deficiencies |
SPD |
spectral power distribution |
SR |
sampling rate |
SRS |
shoulder rumble strip |
SSA |
Safe System Approach |
SSD |
stopping sight distance |
SV |
subject vehicle |
SVROR |
single vehicle run off road |
TBL |
through bicycle lane |
TCD |
traffic control device |
TER |
truck escape ramp |
TWLTL |
two-way left turn lane |
USSC |
United States Sign Council |
UVC |
Uniform Vehicle Code |
v/c Ratio |
volume-to-capacity ratio |
VMS |
variable message sign |
VPD |
vehicles per day |
vph |
vehicles per hour |
VRU |
vulnerable road user |
VSL |
variable speed limit |
VTTI |
Virginia Tech Transportation Institute |
WSS |
weight-specific-speed |
