1:26 "Gulf countries ALL OVER THE WORLD" wow sounds amazing. Except that all Gulf countries only exist in the Middle east. If anyone can find me a Gulf country in N/S America, Africa, East Asia - I will salute them.
You are wrong, these vertical pipes are not called riser but downtake pipes. For piping supplying water through gravity, we don't require AV/AVV. These are used only for direct pumping from ground floor/basement. Those pipes are called risers
Sir I am a Mechanical diploma Engineer and and I want to become a HVAC Engineer from my college days sir my over all Experience 1.5 years in HVAC field