This stuff can't be deluted enough to just rinse away like Phosphoric acid, that would just be like pouring acid down the drain. Think about when cars used vented fill caps, and those fumes from the battery acid would rust the area around the battery, including battery cable clamp bolts, battery hold down, and anything else close by. What everybody did was pour a solution of baking soda and water on everything to neutralize the acid, because a strong acid has to neutralized. But I'm not sure that totally gets rid of it.
Many years ago I had an engine block and heads cleaned at a place that does rust removal dipping for car parts and even whole bodies. When I went to pick up the engine from the machine shop, he complained about it rusting very quickly after each time he rinsed following each machining procedure that he did. Thats the result I got from a professional rust removal business, which I later found out that they used Mutiatic acid.