advice alert appropriate-behavior appropriate-behaviour black care careful caution communicate communication concern information informing large-vehicles less-noise limitations limited message noise-reduction noise-restrictions Noisy outback residential-area restricted restriction restrictions risk risks risky rural-area semi-trailers sign signs symbols town-boundaries trailers transport transportation trucking trucks vehicles warning warning-sign watch watch-out words announcement be-careful beware cars cautious communicating conditions danger dangerous look-out observant red road-conditions road-train safety signage slow-down speed speed-reduction symbol text traffic white