During the warmer summer months you tend to spend a lot more time outdoors. Besides using proper sun protection, you should be also aware of the air quality. The Air Quality Index(AQI) tells you how clean or polluted your outdoor air is, and what associated health effects might be a concern for you. The AQI scale runs from 0 - 500. The higher the value, the greater risk the air is to your health. 100 is generally accepted as the standard where air quality is satisfactory. Levels over 100 are considered unhealthy for sensitive groups of people at first, and then for everyone as the level rises. Those in sensitive groups include: older people, those with lung disease / conditions, and children. Learn more.