Ключевые слова: attention, beware, bio, biohazard, biology, caution, chemical, chemistry, circle, contaminated, danger, deadly, environment, epidemic, explosion, gas, hazard, icon, lab, laboratory, medical, medicine, nuclear, poison, power, prohibition, protection, radiation, radioactive, reactor, reflection, risk, safety, science, security, set, sign, square, symbol, toxic, triangle, virus, warning, waste, yellow, zone,