How to set threshold for bpm process instances and alert creation

Hello Experts,

I have a requirement to set the threshold for BPM process instances in MWS (Administrator–>Business Processes) and set alert email if threshold crossed. Kindly suggest if anyone already implemented this or how to do it.

The threshold like (Process instances <=8000- Normal, Process instances >8000-Warning and Process instances >=12000 (Critical)