alert
area
attention
barrier
beware
build
building
caution
city
closed
construction
direction
ditch
engineering
fence
fenced
forbidden
limit
manufacturing
orange
pipeline
place
progress
project
protection
protective
road
roadside
roadway
roadworks
rule
safety
secured
service
settlement
sign
site
spade
street
symbol
tool
trench
triangle
under
urban
warn
warning
we are working
work
work place