advice alert appropriate-behavior appropriate-behaviour avoid black bright care concern denied directions limitations limited limited-entry not-allowed not-permitted permission-denied prohibited prohibition red restricted restrictions rules sign signs vehicles warning warning sign white yellow access-denied access-limited advising authorised-entry-only authorized-entry-only behave behavior behaviour caution communicate communication construction construction-site danger dangerous entry-denied entry-prohibited information informing limited-access no-access no-entry restriction risk risks risky safety unauthorised unauthorized warning-sign communicating exceptions regulations responsible compound police police-only board car overtakin street traffic ban staff only trespassers zoo 2014 camera media no photography deny fence permission prohibit allow allowed banned dog dogs roadsign 2016 mobile phone no flash no photo phone 2015 do not vector