accident
alert
attention
background
barrier
black
building
careful
caution
construction
danger
dangerous
design
development
do
engineering
equipment
fix
forbidden
hardware
icon
illustration
industrial
industry
job
machinery
maintenance
no
not
notice
prohibited
prohibition
protection
red
repair
restricted
safety
service
sign
site
spanner
stop
symbol
tool
tools
warning
white
work
worker