animals prohibited appropriate behavior appropriate behaviour bicycles prohibited black black and white communicating communication denial denied dog informing littering prohibited no animals no bicycles no littering not allowed not permitted permission denied prohibited prohibition prohibitions rules sign warning white deny fence no-entry permission prohibit close closed lock padlock rust secure security 2015 do not red signs vector advice advising alert appropriate-behavior appropriate-behaviour avoid ban banned behave communicate directive information no-golf not-allowed not-permitted permission-denied restricted restriction restrictions risk risks risky safety signage care concern danger dangers deep deep-water depth direction don’t-alight flowers foliage plants river riverside water wet access-denied access-limited behavior behaviour caution cautious directions keep-out keep-to-path no-access dangerous polluted pollution protect protection toxic toxicity warning sign water pollution water toxicity weathered worn access-limitations authorise authorised authority building electricity electricity-supply exceptions limitations limited limited-entry power power-supply regulations responsible warning-sign inform message please polite rectangle rectangular text words approval approved green park permitted public-park vehicle