Ключевые слова: alert, alertness, attention, avoid, background, beware, black, careful, caution, chrome, cog, cogwheel, equipment, first, gear, gearwheel, instruction, machine, machinery, mechanics, mechanism, metal, metallic, nickel, precaution, prevent, prevention, procedures, production, proper, protect, protection, protective, regulation, risk, safe, safety, safety first, scratch, security, steel, symbol, tool, unsafe, warn, wheel,