ahead
attention
barrier
beware
car
careful
caution
collection
control
cross
crossing
danger
dangerous
drive
engine
gate
icon
illustration
isolated
level
metal
object
open
pole
railroad
railway
road
roadside
roadsign
safe
safety
set
sign
signage
signal
signpost
simple
steam
symbol
technology
track
traffic
train
transport
triangle
warning
way
white