access
accident
area
attention
background
barricade
barrier
boundary
caution
closed
closeup
concept
construction
cordon
crime
cross
danger
dangerous
equipment
fence
forbidden
hazard
investigation
line
murder
order
plastic
police
protect
protection
red
restricted
restriction
ribbon
risk
road
safety
scene
security
signal
stop
stripe
striped
symbol
tape
traffic
urban
warning
white
zone