Unless someone has plumbed their house to use "grey water" inappropriately, the water source in ANY home, etc., should be the same at ANY sink, ANY tub / ANY shower, ANY washer (dishes or clothes), ANY icemaker: ANY first use of water.
Outside taps are typically not softened in a well-based system.
So if the SOURCE is ok, ALL the water in THOSE locations is OK.
For a well, you can get bacteria. This requires a bleach treatment and retesting. During the time of the bacteria, boiling is important.
Sometimes city water supplies have problems; this leads to boil advisories.
NYC water is far cleaner than bottled water.
Greywater / grey water = water after a first use from a sink, shower/tub, or laundry
THAT (possibly with treatment) can be used for irrigation, flushing toilets.
Black water is after use in a toilet.
