TOC can come from the feed water made use of to supply UPW, from your components accustomed to Express the UPW (additives during the manufacturing piping goods or extrusion aides and mould release agents), from subsequent manufacturing and cleaning operations of piping units, or from filthy pipes, fittings, and valves. https://newsprospect.com/the-ultimate-guide-to-pure-water-cleaning-with-a-water-fed-pole-for-solar-panel-cleaning/