For hydro-jetting, isolate the line, install a backflow preventer, begin with lower PSI, then increase as needed

https://astro-wiki.win/index.php/Selecting_an_Expert_for_Septic_Tank_Pumping_and_Cleansing_on_a_Budget_plan

For hydro-jetting, separate the line, install a backflow preventer, start with lower PSI, then increase as required, utilizing proper nozzles to scour biofilm, roots, and scale without hurting pipes.