I think they run on about 80 decibels so they're not mega loud but if your using it all day every day then your customers arent going to be too impressed. I clean a glass canopy and circular vestibule for a mill feed company in Ashbourne. They pay very well and these are additional to the window cleaning, very large job - the jetwashing is right next to the office area, just really aware of thump thump thump of the constant noise. Would be ideal if you could get em quiet. 1800 psi shift anything combined with pure water. I may still use jet wash with pure water - particularly for this