caution hazard roadwork sign slow traffic warning workers workman workmen alert appropriate-behavior appropriate-behaviour black blue care communicating communication concern danger dangerous denied directions disapproval disapproved inform information informing not-allowed not-permitted permission-denied prohibited prohibition prohibitions protect protection red restricted restrictions risks risky rules safety signs symbols warning-sign white words ban banned entry human illegal man no prohibit road roadsign tresspass woman 2014 artwork button medical purple vector virus website computers electronics New stop biohazard exclamation point fire flame lightning pictogram radioactivity skull symbol bar barrier crossing cutout fence isolated rail railroad railway Railway crossing roadsigns forbidden plate street transport way advice announcement be-careful beware careful direction footpath lookout observant pathway pedestrian pedestrians risk security walk walkers walking watch watch-out yellow approval approved bush-reserve conservation conserve control controlled dog dogs lead leash natural nature observation observe old park permitted pets public-park rust rusty