Typically, clean outdoor air contains 2000–3000 ions per cubic centimeter. However, on average, people spend 90% of their time indoors. And, according to the US Environmental Protection Agency, the air inside our homes, schools and offices is often two to five times more polluted than the outside air. Inside a building with natural ventilation, the number of ions drops below 500/cm3, and in most buildings with ducted air-conditioning systems, air ion levels above 100/cm3 are rare. These low ion environments contribute to fatigue, exacerbate breathing issues and contribute to overall poor health.