What are the pm2.5 levels used as breakpoints on Purple Map?

I have a Flex outside and I want to be sure I understand the pm2.5 levels being used to compute the US EPA AQI I see on the map for my sensor.

I am using real-time and applying the US EPA “conversion”.

Also, I am not sure which item(s) in the LAN JSON data is being used.

Can someone please help confirm all this? Thanks!