I consider softwash under 500 psi. No pressure under 100 psi. Low pressure under 1500 psi. As measured as the tip.
I thought you were talking about softwashing since that's the title of your topic.
There are also people who just spray through a pump with "no pressure". They are also calling this "softwash" . The RCIA was trying to bash power washing last year and spreading fear about it in order to promote this type of cleaning.