The coating is tougher than the bond line
A cured resin floor shrugs off water and normal pressure easily. What a pressure washer can defeat is an edge: a coating termination at a door line, a chip from a dropped tool, or a crack, where a high-pressure jet can drive water sideways under the film and start lifting it. That is why the rule is about where you point it rather than about whether to use it at all.
Settings that are safe
A 25 or 40 degree fan tip spreads the force over a wide area and cleans effectively without concentrating energy. A zero degree pencil jet does the opposite and will cut into a coating if held still. Keep the wand around 30 to 45 centimetres off the surface, work in overlapping passes, and keep moving. Most residential electric washers are well under the pressure that could cause trouble; petrol machines are the ones to be careful with.
What to clean with
Warm water and a neutral or mildly alkaline cleaner handle almost everything. Degreaser works on oil deposits and should be rinsed thoroughly. What to avoid entirely is anything acidic, including many concrete cleaners sold for bare slabs, and anything containing citrus solvents, which soften some topcoats over time. If a product does not say it is safe for resinous flooring, it is not worth the experiment on a $5,000 floor.
Where the water goes
This is the practical question in a garage with no drain. Pressure washing puts a surprising volume of water on a floor, and it needs a route out rather than a route into the house or under a wall plate. Squeegee toward the door as you go, and if the garage falls the wrong way, a wet vacuum is a better tool than a washer. In a basement, do not pressure wash at all: mop and scrub instead.
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