ba1969 burn danger fire hot mark red rubber stamp warning word accident attention caution danger sign dangerous disorder edge fall fraction fracture hazard hazardous icon injury label labels materials pictogram plate risk risks rule safety shield sign signs stage stumble symbol symbols triangle tripping tripping hazard uncertainty warning signs watch yellow beware bus car drive road security street traffic transportation travel vehicle animal black cat civilisation nature shape square wild dog elephant cloud evening fear heaven storm sunset thunder animals ban dogs no prohibition commute commuter public transport roadsign shuttle tram tramway tramways blue clouds san diego sky stop sign words clear emergency escape exit keep metal text