Particulates
These include silt, plumbing pipe debris and colloids, all suspended particles that can plug filters, valves, tubing and reverse osmosis membranes.  They are visible as cloudiness and can be detected by using filtration, gravimetric means and microscopic methods.

Removal of particulates from water
Particulates are most often removed by filtration, microporus filtration, an ultrafilter, or reverse osmosis, which typically removes 90-99% of all contaminants.  The NCCLS considers water to be particulate-free when it has passed through a 0.2 micron filter.