[Pollution] Difference between Chilean measures and international ones

As I was cleaning my bookmarks, I found one that I did not use for a long time, to the website from the Chilean government about the air quality. It was the occasion to compare the information it provides (based on the same data, from the same captors) to the website that I now use, aqicn.org:

The air, if not as bad as other times (the peaks of pollution in Santiago are from June to August, when it is winter in the South Hemisphere) is bad currently (there are fires in various communes), but the difference is already striking (see here for a comparison for all cities of Chile):

• On Wednesday, the air quality was "Moderate" by international standards, while completely "Good"by Chilean standard;
• on Thursday morning, the air was "Unhealthy for some" by international standards, while still "Good" by the standards of Santiago's administration; and 
  
• on Thursday evening, the air was "Unhealthy" by international standards, while still mostly "regular" by Chilean standard:
  
  

There is no way to know how much of this gap is due to ignorance, and how much is due to political scheming, but in the end the Chilean government is twice less demanding in air quality than international websites, judging one day's air as "good" when internationally it already one pr too levels worse than good, i.e. "moderate" or "Unhealthy for some" (the fact that "regular" is not "bueno" on the Chilean website would make for an another debate: on the international website it is only "moderate", not "regular", after "good").

And the gap between the two reports is increasing as the pollution gets worse...