Ключевые слова: air pollution, air quality, air quality control, anti smoking, cautionary signage, danger, danger alert, environmental awareness, environmental caution, environmental consciousness, environmental harm, environmental health, environmental impact, environmental responsibility, forbidden, harmful effects, harmful emissions, harmful substances, hazardous fumes, health and safety, health hazard, no entry, no smoking, no smoking zone, pollution, prohibited, public health, public safety, red alert, restricted access, restricted area, restricted zone, safety, smoke, smoke ban, smoking cessation, smoking prohibition, stop sign, toxic, toxic smoke, warning, warning sign,