alert
art
attention
background
barrier
black
border
boundary
build
caution
cone
construct
construction
danger
design
element
equipment
flat
forbidden
highway
icon
illustration
isolated
marking
object
obstacle
orange
outline
pictogram
plastic
reflection
repair
road
safety
security
sign
signal
single
site
stop
street
striped
symbol
traffic
transportation
warning
web
white
work