Pharmaceutical and chemical industries, residential buildings, hospitals, and any other building in which people work contain many kilometers of air conditioning and ventilation ducts. These ducts accumulate dirt and germs which reduce efficiency of air flow on the one hand and cause distribution of contaminated air on the other hand. The spread of infectious diseases, deterioration of air quality, and increased difficulty breathing all require ongoing, timely cleaning of ventilation ducts including complete vacuuming of all dirt and debris.