Ключевые слова: abstract, accesschamber, asphalt, background, bitumen, cablechamber, center, circular, city, closeup, concrete, confinedspace, construction, cracked, damaged, direction, dividing, double, hatch, hole, industrial, industry, inspectionchamber, iron, lid, line, maintenancehole, manhole, mark, marking, material, metal, nobody, outdoors, pavement, paving, plate, road, round, sewer, solid, steel, stripe, surface, texture, underground, urban, utilityhole, way, white,