a4
accident
alert
architecture
area
assembling
attention
authorised
barrier
beware
building
careful
caution
construction
crane
danger
dangerous
development
extreme
forbidden
high
industrial
industry
keep
not
out
personel
personnel
prohibition
property
protection
red
restriction
risk
safe
safety
secure
security
sign
signboard
site
skull
symbol
trespassing
typicalsign
unauthorized
work
workplace
zone