Ключевые слова: alertness, architecture, backdrop, backgrounds, biohazard symbol, black color, built structure, cement, composition, concrete, concrete block, concrete wall, construction material, design, fear, forbidden, hazardous area sign, horizontal, no people, old, pattern, physical structure, place of work, pollution, porous, problems, protection, risk, rusk, safety, security, sign, stained, stone material, striped, surrounding wall, template, textured, textured effect, threats, wall building feature, wallpaper decor, warning sign, weapons of mass destruction, weathered, yellow,