AQHI or AQI - The Difference

How is this new AQHI different from the AQI?

While air quality has been reported for many years, this new Air Quality Health  Index has been created with a different goal -- to  report on the health risk posed by a specific level of air quality.  Here is a bit more detail about how they are different;

What is Reported -  Traditionally, the Air Quality Index reported current air quality based on a specific level of an air pollutant.  The new Air Quality Health Index reports on the health risk posed by that same air quality.

How it is measured -  Traditionally, the Air Quality Index determined air quality to the highest value of only one pollutant.  The index rating for the new Air Quality Health Index is the sum of those health risks from each of the pollutants in the index.

Why this is more useful to most of us -  The new Air Quality Health  Index reflects current knowledge of the health effects associated with air pollution. The traditional Air Quality Index is based on air quality standards using science from the 70s and 80s and were largely based on environmental and not human health concerns.

Which is better?
While both the traditional Air Quality Index and this new Air Quality Health  Index have their respective strengths, this new index has been designed to tell you more about your health risk from air pollution on any given day. 

Why does this new index show improved air quality in my community compared to the old AQI?
While the two indexes were developed to show different results and should not be compared, it is inevitable that there will be comparisons. The new Air Quality Health  Index captures health risk for a community and those health risks are more sensitive to some pollutants in some locations than others.  In some cases, the air quality will appear to be improving compared to the traditional air quality index because the risks that are being measured are smaller relative to the standards-driven air pollution concentration.  In other communities it will appear worse because the opposite is true.