Since I've been back in Beijing, the Air Quality Index (AQI) has been pretty bad. The past few days have been especially nasty. The AQI meter that we rely on is the one on top of the U.S. Embassy building in Beijing. The one provided by the Chinese government does not seem to be quite as reliable. Today's reading is: The scale is defined from 1 - 500, broken into the following levels:

Good	0-50
Moderate	51-100
Unhealthy for Sensitive Groups	101-150
Unhealthy	151-200
Very Unhealthy	201-300
Hazardous	>300

The U.S. EPA sets the thresholds, although I'm not sure if there are more quantitative measures, such as x% increase in illness with y minutes of exposure. For now, I'm just staying inside and hoping that it improves before Jess and the kids return.