danger drown drowning lake sign swimming warning water advice alert announcement appropriate-behavior appropriate-behaviour avoid be-careful beware black care caution communicating communication concern crocodiles crocs dangerous directions information informing no-swimming not-allowed not-permitted permission-denied prohibited prohibition protect protection red risk risks risky rules safety signs unsafe warning-sign white aware awareness careful forklift listen Look looking lookout moving moving-machinery observant rain rain-drops trams watch watch-out work workplace yellow area children observance school schools slow slow-down slower speed time times zone advising blue cars hazard hazardous motorcars orange road-sign roadwork signage symbol traffic vehicles words workers workmen arrow attention electricity energy high high voltage industrial lightning pictogram power voltage barrier colors colours sign. electric fence wires deer ice road rural snow triangle camp-fire fire flame hexagon security rail railway track transport