Most businesses and facilities struggle with air quality issues related to outdoor pollution to varying degrees. Outdoor pollutants such as traffic fumes, industrial emissions, combustion by-products, and pollen spread into the facilities through leaks in the construction, open windows, cargo bays, and the ventilation system, contaminating the indoor air. In fact, indoor air is often up to 50 times more polluted than outdoor air, according to the European Union, ECA report no 23. This in turn increases the risk of the people who stay in the building suffering from serious health issues. For many businesses, this also means increased absence and decreased productivity. In other words, poor air quality can have long-term negative effects on both the people who stay in the facility and the business itself.