Ключевые слова: access, accessibility, antiterrorism, asphalt, barricade, barrier, black, border, bump, bumpy, concrete, crosswalk, danger, diagonal, driveway, empty, equipment, hump, impediment, jump, line, metal, obstacle, obstruction, outdoors, parking, prevention, protection, risk, road, roadblock, roadway, row, security, sign, speed, stop, street, striped, surface, traffic, transportation, urban, warning, yellow, zebra,