advice aid alert announcement assist assistance availability available aware awareness caution communicating communication concern directions equipment extinguish extinguisher fire fire-control fire-extinguisher firefighting help information informing location observant observe red risk risks safety sign signs white background blade blood circle circular closeup construction cut dangerous detail disc disk electric images industrial industry iron isolated machine metal mill object old round saw sharp shiny silver stains steel teeth tool wheel work access bollard calculating calculations color colors colour colours computerised computerized flowers laser level levels man measurement measuring men pavement plants roadside shrubbery shrubs skilled skills surveying surveyor technology theodolite trees triangulation tripod tripods worker workman chairs coastal distant edge edges facilities fishermen fishing fishing-rods floating foliage frames framework greenery huts leisure mountains mountainside opportunities people platforms pontoons recreation recreational sea shelters shore shoreline slopes sloping supplies vegetation water active danger emergency emergency services fire and rescue fire brigade fire fighters fire fighting firemen hoses hosing house fire protection protective protective clothing pumping pumps smoke spraying suburban trucks uniforms vehicles angles arm digger elevated elevation external height heights high hydraulics lifting machinery perspectives post-hole-digger power power-pole raised raising replacement replacing risky service spiraling spiralling up-high